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Compact Proton and Carbon Ion Synchrotrons for Radiation Therapy

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Delayed cerebral necroses after irradiation are to be divided into hemispheric and midline lesions, as they differ from each other in several aspects. Apart from the symptoms, they are differing in the duration of latency, in the course and prognosis, and also with regard to morphology. Though there is no doubt that radiation tolerance of cerebral midline structures is relatively limited, on biological grounds, evidence of a difference between the tolerated doses could not be given from the existent inhomogeneous radiation data, with the help of the NSD-concept. Radiation planning for the region of the head, nevertheless, carefully should avoid in every case to involve the structures of the cerebral midline.

International Nuclear Information System (INIS)

This document is the report of a task group of the Radiation Therapy Committee of the AAPM and has been prepared primarily to advise hospital physicists involved in external beam treatment of patients with pelvic malignancies who have high atomic number (Z) hip prostheses. The purpose of the report is to make the radiation oncology community aware of the problems arising from the presence of these devices in the radiation beam, to quantify the dose perturbations they cause, and, finally, to provide recommendations for treatment planning and delivery. Some of the data and recommendations are also applicable to patients having implanted high-Z prosthetic devices such as pins, humeral head replacements. The scientific understanding and methodology of clinical dosimetry for these situations is still incomplete. This report is intended to reflect the current state of scientific ...

International Nuclear Information System (INIS)

Purpose: A retrospective analysis was undertaken to determine the indications for, the efficacy of, and the long-term complications of two courses of total skin electron beam therapy for mycosis fungoides. Methods and Materials: A retrospective analysis of 15 patients with the pathologic diagnosis of mycosis fungoides treated in the Department of Radiation Oncology at Stanford University Medical Center between 1968 and 1990 was performed. All patients received two courses of high-dose electron beam therapy to the skin. The mean dose for the total skin treatment for the first course was 32.6 Gy and 23.4 Gy for the second course of treatment. Results: Following the first course of total skin electron beam therapy, 11 of 15 had a complete response, with a mean duration of 11.6 months. All patients received adjuvant therapies between the first and second courses of high-dose total skin ...

UK PubMed Central (United Kingdom)

PurposeTo evaluate four planning techniques for stereotactic body radiation therapy (SBRT) in lung tumors.Methods...Full Text Available

Science.gov (United States)

Prostate Cancer; Psychosocial Effects of Cancer and Its Treatment; Radiation Toxicity; Sexual Dysfunction and Infertility

International Nuclear Information System (INIS)

Purpose: To evaluate the effect of low-dose radiation therapy and surgery on local control in patients with Ewing's Sarcoma. Materials and Methods: Between 1979 and 1995 24 patients (ages 4-47) with Ewing's sarcoma were treated with combined modality therapy that included multi agent chemotherapy, surgical resection, and radiation therapy. Twelve patients had metastatic disease at the time of presentation (pleura = 3, lung = 5, bone 4). Tumor location was central in 16 and peripheral in 8. Multi agent chemotherapy consisted of vincristine/actinomycin D/cyclophosphamide/doxorubicin in 19. The same agents with the addition of ifosfamide and etoposide were given in 5. The extent of resection was considered to be radical in 14 and of the 16 patients who received preoperative chemotherapy, 5 were found to have a pathologic complete response. All patients with lung metastases at diagnosis ...

KoreaScience (Korea)

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UK PubMed Central (United Kingdom)

Adaptive radiation therapy (ART) is the incorporation of daily images in the radiotherapy treatment process so that the treatment plan can be evaluated and modified to maximize the amount of radiation...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundThe aim of this study was to compare and to validate different dose calculation algorithms for the use in radiation therapy of small lung lesions and to optimize the treatment...Full Text Available

UK PubMed Central (United Kingdom)

PurposeA dosimetric comparison between multiple static-field intensity-modulated radiation therapy (IMRT), multi-arc intensity-modulated arc therapy (IMAT) and single-arc...Full Text Available

Medline Plus

... acquired, which we then volumetrically fuse with the 3D image set from the MR. And by doing ...

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No abstract prepared

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The patient positioning and repositioning control in radiation therapy all along the treatment can be conducted using a variety of X-ray sources and imaging detector devices. The development of image guided radiation therapy techniques leads to more frequent use of this imaging control. In this article we summarize the current methods for measuring the dose delivered by X-ray imaging devices used in radiation therapy, as well as basic proposals to take account of these imaging doses for prescribing, recording and reporting radiation therapy treatment. (authors)

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The proton therapy gives an irradiation adapted to the shape and the depth of tumors ( eyes, head and neck) with a millimetric, even sub millimetric precision for the ophthalmological tumors. It is equally an excellent tool for the pediatrics tumors. For numerous treatments in France the proton therapy is associated to the photons treatments (x radiation). however, others physical treatments could modulate the medical offer, such thermal therapy or treatments by ultrasonic waves. (N.C.)

International Nuclear Information System (INIS)

Radiation therapy has had a significant and an expanded role in the management of cancer of the pancreas during the last decade. In particular, for locally advanced disease, radiation therapy has improved the median survival of patients to 1 year. Intraoperative electron beam therapy has been applied to unresectable and resectable pancreatic cancer in an attempt to enhance local control of disease and to improve patient survival. This paper presents a survey of the role of radiation therapy in treatment of cancer of the pancreas, provides information on the radiobiological aspects of this treatment modality and details the physical and dosimetric characteristics of intraoperative radiation therapy with electrons. Presented are the design specifics of an applicator system, central axis beam data, ...

UK PubMed Central (United Kingdom)

Several compact proton accelerator systems for use in proton therapy have recently been proposed. Of paramount importance to the development of such an accelerator system is the maximum kinetic energy...Full Text Available

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To evaluate the usefulness of radiation therapy alternative to surgery for clinical N0-N1 non-small cell lung cancer (NSCLC). From 1976 through 1989, 116 patients with NSCLC without mediastinal involvement were treated with definitive radiation therapy alone at Gunma University Hospital. All patients were treated with once-daily standard fractionation using 10 MV X-rays. The total dose ranged from 60 Gy to 80 Gy. The actuarial 2- and 5-year survival rates of the entire group were 43% and 20%, respectively with a median survival time of 19 months. The survival of 76 patients with stage T2 tumors was significantly better than that of 28 patients with T3 tumors (mean survival time 21 versus 15.5 months; p<0.05). Sixty-two patients with tumors less than 5 cm in diameter had a 2-year progression rate of 20%, in comparison with 39% of 54 patients with tumors greater than 5 cm. The ...

British Library Electronic Table of Contents (United Kingdom)

Prostate cancer can be successfully treated using dynamic adaptive external beam radiation techniques along with interstitial brachytherapy to deliver curative therapies with low urinary, rectal and erectile function morbidity. Through the use of sophisticated, state-of-the art radiographic imaging for staging and treatment planning, a precise, individual design for treatment is accomplished. Symptom management and patient education are of paramount importance and are integrated throughout the treatment process.

International Nuclear Information System (INIS)

Despite high local control rate in Ewing's sarcoma the exact indication of radiation therapy is still controversial as well as the choice of the target volume and the optimal dose of radiation. The importance of the quality of radiotherapy has been stressed in recently published data and has shown a significant impact on long term local control with adequate radiation therapy. The dramatic improvement of precision allowed by the conformal therapy and three dimensional dosimetry allow to expect a decrease of late effects expected for second malignancies. However, late sequelae and radio-induced osteosarcoma still remain the major side effects after radiotherapy. The authors discuss the results of the main trials on Ewing's sarcoma on the choice of dose and target volume. Surgery is still the preferred choice for small tumors if the foreseen outcome is identical. ...

International Science & Technology Center (ISTC)

Development of Portable Normobaric Hypoxia and Pulsed Magnetic Field Firmware System for Enhancement of Radio- and Non-specific Resistance in Workers of Environmentally Hazardous Industries

UK PubMed Central (United Kingdom)

Adaptive radiation therapy for liver cancer has the potential to reduce normal tissue complications and enable dose escalation, allowing the potential for tumor control in this challenging site....Full Text Available

International Nuclear Information System (INIS)

Forty cases of Ewing's sarcoma of various sites had attended the Department of Radiotherapy at the Wanless Hospital and the Miraj Medical Centre, attached to the Government Medical College, Miraj, Maharashtra, from January, 1970 through December, 1979. There were 28 male patients and 12 female patients in the series with a male to female ratio of 2.3:1. The youngest patient in the series was a female of 6 years of age with the tumour in the scapula and the oldest patient was a 32-year-old male with a lesion in the metacarpal bone. Sixty per cent of the cases were seen in the second decade. The average age of the patients was 13.5 years. The bones of the lower extremities were most commonly involved with the highest number (35 per cent) of the cases occurring in the femur. Involvement of the bones of the right side of the body was almost equal to that of the left side. Swelling over the site of the lesion and pain over the swelling were the most ...

International Nuclear Information System (INIS)

Purpose: To assess the relationship between large intracranial vessel occlusive vasculopathy (vasculopathy) and radiation therapy, and to clarify the clinical efficacy of magnetic resonance (MR) imaging in the diagnosis and screening of the vasculopathy. Methods and Materials: We retrospectively evaluated the medical records and serial MR images for 32 pediatric patients, in whom radiation therapy had been given to fields including the circle of Willis and major cerebral arteries. All children had periodically undergone follow-up neurologic assessment and MR imaging examinations at Kanagawa Children's Medical Center for more than one year after radiation therapy (range 1.3-14 years). Patients who had not remained free of tumor progression up to the time of final evaluation were excluded. Results: Vasculopathy developed in 6 of 32 patients 2-13 years after ...

UK PubMed Central (United Kingdom)

For intensity modulated radiation treatment (IMRT) dose reconstruction, multileaf collimator (MLC) log files have been shown applicable for deriving delivered fluence maps. However, MLC log files are...Full Text Available

Science.gov (United States)

Two patients who developed large intracranial vessel occlusion after standard radiation therapy for brain tumor are described. This form of vascular occlusion is usually seen in patients who have previously been treated by radiotherapy for intracranial tumor who then develop a relatively acute change in neurologic status. Histology of the lesion mimics accelerated focal arteriosclerosis. The clinical and radiographic manifestations of one case were highly atypical. The vasculopathy became evident shortly after termination of radiation therapy for a fourth ventricular ependymoma, and the angiographic picture stimulated a diffuse arteritis. The second patient was more typical, with clinical symptoms developing 12 years after radiation therapy for an oligodendroglioma. Occlusion of a proximal vessel that had been included in the radiation port ...

Energy Technology Data Exchange (ETDEWEB)

During the past 10 years, five infants with Kasabach-Merritt syndrome (K-M) receiving radiation therapy were reported. We investigated whether radiation therapy for K-M was useful and what the unfavorable factors of K-M were. During the past 10 years, we have treated five infants with K-M. The syndrome occurred at ages ranging from birth to 4 months. The incidence of female to male ratio was 3:2. Among 5 cases, the site of hemangioma was as follows; shoulder, anterior chest wall, lower abdominal wall, face and neck and inguinal site. All 5 cases received medication to control the coagulopathy including prednisone and blood transfusion at first. Because the platelet count and the bleeding tendency did not improve in any case, these cases received radiation therapy. Total dose ranged from 5 to 10 Gy and fraction-size ranged from 0.5 to 1.75 Gy. Irradiation session ...

International Nuclear Information System (INIS)

Little clinical evidence has been provided to show the minimization of radiation resistance of tumors using high linear energy transfer radiation. We therefore investigated the radiobiological and molecular pathological aspects of carbon beam therapy. A total of 27 patients with squamous cell carcinoma (SCC) of the cervix were treated using a carbon beam and 50 control patients with SCC of the cervix using a photon beam. The expression of Ki-67, p53, and p27 proteins before radiotherapy and 5 and 15 days after therapy initiation were investigated using immunohistochemistry. Similar changes were observed in Ki-67 labeling index (LI) and p53 LI during carbon and photon beam therapies. However, for carbon beam therapy, the mean p27 LI significantly decreased from 25.2% before treatment to 18.6% on the 5th day after treatment initiation, followed by a significant ...

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External radiation dose exceeded 5,000 rad in three cases, and intravaginal radiation dose was 5,000 rad in one case. Radiation damage including perforation was seen in the end of ileus in one case, in the sigmoid and rectum in two cases, and in the end of ileus, sigmoid and rectum in the last case. Satisfactory results were obtained by the removal of the ileocecum in the case of the damage in the end of the ileus. However, only colostomy was performed for the damage in the sigmoid and rectum.

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Retrospective analyses were performed to evaluate the therapeutic efficacy of intra-oral cone (IOC) radiation therapy for carcinoma of the oral tongue, especially about its faculty of local control and complications. Thirty-nine patients with squamous cell carcinoma of the oral tongue were treated with IOC radiation therapy alone or in combination with external irradiation. IOC radiation therapy was given not only for T1 and T2, but also for T3 tumors. Hypofractionation was used for IOC radiation therapy. The 2 year local control rates, including surgical salvage, for T1, T2, T3 and T4 were 100%, 73.3%, 40% and 0%, respectively. The 5 year actuarial survival rates for Stage I, II, III and IV were 100%, 65.3%, 35.4% and 0%, respectively. The incidences of radiation complications, i.e. soft tissue ...

UK PubMed Central (United Kingdom)

Recurrent or primary carcinoma of the breast en cuirasse, which may involve the skin of the entire thorax and abdomen, cannot be controlled by means of surgery or conventional local irradiation. The...Full Text Available

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A long-term follow-up of a patient with beta thalassaemia with intra- and extraspinal extramedullary haematopoietic tissue compressing the spinal cord is presented. Extramedullary haematopoietic nodules are a rare cause of spinal cord compression and should be included in the differential diagnosis, especially in patients from Mediterranean countries. Treatment with radiation therapy solely failed, giving rise to the need of surgical intervention. Surgical decompression of the spine and the removal of the culprit lesion compressing the spine were performed. Postinterventional radiation therapy was applied to the spine. A relapse had to be treated again by surgical means combined with postinterventional radiation therapy. A complete relief of the symptoms and control of the lesion could be obtained.

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Electron beam therapy has often been used for radiation therapy of carcinomas of the buccal mucosa, though side effects, including stomatitis and dermatitis, are known to exist. We experimented using the additional back scatter and transit with the phantom under a lead plate within the irradiation field, in order to better focus the dose on the target volume moreover, we fabricated a mouthpiece fitted with a lead plate shaped to the target volume, and with respect to the influence of the mouthpiece on stomatitis and dermatitis, obtained good clinical results. (author).

International Nuclear Information System (INIS)

Records of 154 patients with Ewing's sarcoma treated at the National Cancer Institute were reviewed to assess the incidence and risk of developing isolated central nervous system (CNS) Ewing's sarcoma. Sixty-two of the 154 patients had received CNS irradiation and intrathecal (i.t.) methotrexate as part of their initial therapy to prevent the occurrence of isolated CNS Ewing's sarcoma. The risk of developing isolate CNS Ewing's sarcoma was greatest within the first two years after diagnosis and was approximately 10%. The overall risk of CNS recurrence in the group of patients receiving DNS treatment was similar to the group receiving no therapy directed to the CNS. The occurrence of isolated CNS involvement was not prevented by the use of CNS irradiation and i.t. methotrexate. Because of a lack of efficacy to the CNS irradiation regimen, current treatment regimens do not include therapy directed to CNS.

International Nuclear Information System (INIS)

The effect of UV radiation in the wavelength region 230 nm to 302 nm on the ability of an irradiated mammalian cell to reactivate UV-irradiated mammalian virus was tested. An action spectrum for radiation enhanced reactivation (RER) is presented. The shape of the action spectrum points to a combined nucleic acid-protein target for UV radiation effects on this cellular parameter. An analysis of the results of others involving the biochemical and photobiological events involved in RER does not allow us to distinguish which macromolecule is the major contributor to this effect. Studies involving an analogous phenomenon in bacteris (Weigle reactivation) imply that RER and WR amy involve similar mechanisms. (author).

International Nuclear Information System (INIS)

Dose calculations for radiation arc therapy are traditionally performed by approximating continuous delivery arcs with multiple static beams. For 3D conformal arc treatments, the shape and weight variation per degree is usually small enough to allow arcs to be approximated by static beams separated by 5"0-10"0. But with intensity-modulated arc therapy (IMAT), the variation in shape and dose per degree can be large enough to require a finer angular spacing. With the increase in the number of beams, a deterministic dose calculation method, such as collapsed-cone convolution/superposition, will require proportionally longer computational times, which may not be practical clinically. We propose to use a homegrown Monte Carlo kernel-superposition technique (MCKS) to compute doses for rotational delivery. The IMAT plans were generated with 36 static beams, which were subsequently interpolated into finer angular intervals for dose ...

UK PubMed Central (United Kingdom)

Microplanar beam radiation therapy has been proposed to treat brain tumors by using a series of rapid exposures to an array of parallel x-ray beams, each beam having uniform microscopic thickness and...Full Text Available

UK PubMed Central (United Kingdom)

IntroductionIrradiation of normal, non-malignant bone during cancer therapy can lead to atrophy and increased risk of fracture at several skeletal sites, particularly...Full Text Available

UK PubMed Central (United Kingdom)

Voxel-based prescriptions of deliberately non-uniform dose distributions based on molecular imaging, so-called dose painting or theragnostic radiation therapy, require specification of a transformation...Full Text Available

UK PubMed Central (United Kingdom)

Patients experiencing several cancers can be a challenge, as optimal treatment options for the different cancers might interfere with each other. In this case report, we present a woman diagnosed with...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundTo compare the differences in dose-volume data among coplanar intensity modulated radiotherapy (IMRT), noncoplanar IMRT, and helical tomotherapy (HT) among patients with...Full Text Available

UK PubMed Central (United Kingdom)

Purpose: Reverse helical cone-beam computed tomography (CBCT) is a scanning configuration for potential applications in image-guided radiation therapy in which an accurate anatomic image...Full Text Available

International Nuclear Information System (INIS)

Purpose: To determine if involved field radiation (IF) is equivalent to standard whole bone radiation (SF) in local tumor control; to establish patterns of failure following treatment; and to determine response, event-free survival (EFS), and overall survival rates from multidisciplinary therapy in Ewing's sarcoma. Methods and Materials: Between 1983 and 1988, 184 children with Ewing's sarcoma were enrolled onto Pediatric Oncology Group 8346 (POG 8346). A total of 178 (97%) met eligibility criteria; 6 had pathology other than Ewing's sarcoma. Induction chemotherapy of cyclophosphamide/doxorubicin (adriamycin )(C/A) x 12 weeks was followed by local treatment either surgery or radiation therapy and C/A, dactinomycin, and vincristine for 50 weeks. Resection was advised for patients with small primary tumors if accomplished without functional loss. Forty patients ...

International Nuclear Information System (INIS)

Outage is a specific period of time for radiation protection in a nuclear power plant, in which the radiation risk and collective dose are both at the highest level. In this article, the practice and experience of occupational exposure control in the outages of Daya Bay Nuclear Power Plant are introduced through following aspects: early involvement in outage preparation by radiation protection service, control of source term, radiation protection and safety management in the outage implementation processes, the effectiveness of the plant's safety management network and overall involvement of all staffs of the plant, experience feedback and continuous improvement in radiation protection management, etc

Energy Technology Data Exchange (ETDEWEB)

Authors developed a C-arm type radiosurgery system of the linear accelerator suitable for stereotactic radiation therapy and a software for arranging 3-dimensional therapy in the system. In this system, the gantry far conical irradiation of 4 MV (0.6-3 Gy/min) and 6 MV (0.9-4.5 Gy/min) X ray or electron beam for the therapy was connected to a newly designed C-arm and was made capable of rotating around either of the axes crossing vertically. With this system, it became unnecessary to move the bed table of the patient for getting suitable distribution of radiation dose. The local accuracy which was measured by the CCD videocamera on the gantry, was within 0.5 mm from the radiation center. The system made it possible to shorten the irradiation time and to improve the local accuracy of irradiating site. The clinical trial was begun from June, 1996. (K.H.)

International Nuclear Information System (INIS)

It may result in acute radiation syndrome after body is exposed to ionizing radiation. The one of long-term effects of irradiation injury is leukemia. The bone marrow cells (BMC) transplantation including stem cells is the only effective therapy for acute radiation syndrome patients. Recently, with the advancement of stem cell research that the stem cells have multipotential and can convert each other, it may supply the new stem source for the irradiation injury patients. At the same time with the further research of radioprotective reagents, the hematopoietic stem cells proliferation after irradiation injury is promoted

International Nuclear Information System (INIS)

The use of absorbable polyglactin 910 mesh (Vicryl) is described in a case of Ewing's sarcoma of the pelvis. An operation was performed to hold the small bowel and colon out of the pelvis for a temporary period during which radical radiotherapy was delivered. The mesh allowed the temporary displacement of bowel and obviated bowel radiation morbidity. (author).

International Nuclear Information System (INIS)

From 1979 to 1986, 182 patients with biopsy proven diagnosis of Ewing's sarcoma of bone were observed. One hundred of the 182 patients (72 males, 28 females, median age 15.8 years) with localized disease and no previous treatment were treated with chemotherapy (VCR, ADM, CTX, D-ACT) for 15-18 months. Local treatment was radiotherapy (42 patients), surgery (31 patients), or a combination of both (27 pts). Radiation doses ranged from 45 to 64 Gy given with conventional fractionation. Median follow-up was 51.2 months (24-106). Overall and disease-free survival were, respectively, 58.7 and 42.6%. Resected patients tended to have a better local control (Surgery 93.6%, Surgery + Radiation therapy 92.6%, Radiation therapy 69.1%). Disease-free survival was significantly related to the volume of the primary tumor (bulky: 33.2%, not-bulky: 57.7%), to site (extremities 54.6%, central sites ...

Energy Technology Data Exchange (ETDEWEB)

Forty-three patients with basal and squamous cell carcinomata arising on the pinna were treated radically using a 10 MeV electron beam. The technique and dosage are described and discussed. Primary cancer control with retention of the pinna was achieved in 34 patients. Salvage pinnectomy was performed in four patients for recurrence and one patient for radiation necrosis. Two patients with large primary tumours failed to resolve and died of their disease. The advantages for the patient of the policy of primary radical electron beam therapy are discussed.

Energy Technology Data Exchange (ETDEWEB)

A thermoluminescence (TL) sheet and its spatial readout system for in vivo measurement of spatial dose distribution around sources has been newly developed for intracavitary high dose-rate radiation therapy. The TL sheet (40 cm x 50 cm x 200 {mu}m), which is composed of teflon mixed with BaSO{sub 4} (Eu doped) powder, has a linear response with a very wide dynamic range from at least 0.002 cGy to 5000 cGy for {sup 60}Co sources. Phantom test of the TL sheet readout system demonstrated that absorbed dose with TL sheet and that with ionization chamber as standard dosimeter agreed well. For clinical application, TL sheet was attached on an applicator of intracavitary radiation therapy for rectal cancer. After irradiation with high dose-rate {sup 60}Co sources, the in vivo dose distribution on the surface of the rectum was determined. The TL sheet was suggested to provide a convenient means of measuring the ...

International Nuclear Information System (INIS)

We report a patient who developed occlusion of the intracranial major arteries induced by radiation therapy for craniopharyngioma. The patient, a 9-year-old boy, presented with deterioration of vision, nausea and vomiting. He underwent a right ventriculo-peritoneal shunt operation, and the tumor was partially removed. Postoperatively, he received focal radiation therapy with total of 60 Gy. Preoperative cerebral angiography, cerebral vessels had no sigh of occlusive lesion or stenosis. One year after irradiation, he started to have repeated cerebral ischemic attacks. But no regrowth of the tumor was detected on CT scans. Two years and 8 months after irradiation, he suddenly had right hemiparesis. Cerebral angiography revealed severe stenosis of the right anterior cerebral artery (precommunicating segment), middle cerebral artery (horizontal portion) and terminal portion of the right carotid artery. Left ...

Energy Technology Data Exchange (ETDEWEB)

The current state and need for radiation protection training in Finland have been surveyed by the Radiation and Nuclear Safety Authority STUK. The survey sought to determine whether the current requirements for radiation protection training had been met, and to promote radiation protection training. Details of the scope and quality of present radiation protection training were requested from all educational institutes and organizations providing radiation protection training. The survey covered both basic and further training, special training of radiation safety officers, and supplementary training. The questionnaire was sent to 77 educational organization units, 66 per cent of which responded. Radiation workers and radiation safety officers were asked about radiation protection ...

International Nuclear Information System (INIS)

Scattered radiation generated in patient and imaging system has to be considered when quality-assurance tests involve dose detection or image-quality estimations. Measurement of automatic-exposure control dose can be altered by backscattering from intensifying screens of more than 10% and the equipment transmission factor can be overestimated up to a factor of 10 when only primary radiation is used. The sensitivity of intensifying screens depends on the angle of incidence of the radiation and so primary and scattered radiation are detected differently. The quality-control aspects of anti-scatter grids are discussed. (author).

British Library Electronic Table of Contents (United Kingdom)

Purpose: The aim of this study was to assess interinstitutional variations in planning for stereotactic body radiation therapy (SBRT) for lung cancer before the start of the Japan Clinical Oncology Group (JCOG) 0403 trial.Methods and Materials: Eleven institutions created virtual plans for four cases of solitary lung cancer. The created plans should satisfy the target definitions and the dose constraints for the JCOG 0403 protocol.Results: FOCUS/XiO (CMS) was used in six institutions, Eclipse (Varian) in 3, Cadplan (Varian) in one, and Pinnacle3 (Philips/ADAC) in one. Dose calculation algorithms of Clarkson with effective path length correction and superposition were used in FOCUS/XiO; pencil beam convolution with Batho power law correction was used in Eclipse and Cadplan; and collapsed co...

Energy Technology Data Exchange (ETDEWEB)

From 1977 through 1984, 293 previously untreated patients with biopsy proven carcinoma of the uterine cervix were treated by whole pelvis irradiation and high intensity 60Co remote afterloading (RAL) intrauterine tandem techniques in Haiti. The treatment results were analyzed retrospectively to evaluate the therapeutic results and prognostic factors of a strict protocol involving 40 Gy to the whole pelvis (2 Gy/day, 5 days/week). In addition, on the 5th day of the 3rd week, the first outpatient 60Co remote afterloading intracavitary insertion, delivering 7.5 Gy to point A with each insertion, repeated 3 times by a week separation for a total of 4 times. The total TDF for external beam plus RAL was 158 and 175 for early and late effects respectively. One hundred-four patients were evaluable after 1 year or more follow-up, with a median of 26.5 months. No evidence of disease (NED) by Stage at 1 year was: Stage I of 100% (3/3), Stage II of 82% (9/11), Stage III of 80% ...

International Nuclear Information System (INIS)

Purpose: The results of therapy in 288 men with pathologic Stage C prostate cancer who underwent radical retropubic prostatectomy (RRP) were analyzed to determine the effects of adjuvant therapy. Methods and Materials: Twenty-seven of the 288 patients received preoperative neoadjuvant hormonal therapy (leuprolide acetate). Postoperatively, 60 patients received adjuvant radiotherapy (RT) to the prostate bed. Follow-up ranged from 3 to 83 months (median = 32 months). Freedom from failure (FFF) was defined as maintaining a serum PSA level of #<=# 0.3 ng/ml. Results: The FFF was 61% at 3 years and 45% at 5 years for the entire group. The FFF following RRP plus RT was 75% at 3 years and 57% at 5 years as compared to 56% at 3 years and 40% at 5 years for RRP without RT (p = 0.049). The FFF following RRP plus neoadjuvant hormonal therapy was 58% at 3 years and 40% at 5 years as compared to 60% at 3 years ...

International Nuclear Information System (INIS)

This review briefly describes current efforts to develop superradiant sources of coherent radiation for the sub-nanometer range of wavelenghs, using nuclear rather than the atomic or molecular transitions that are stimulated in existing lasers. First the radiative (including Raman) interactions of nuclei with those of atoms and molecules are compared; then the present status of research on the fundamental problems involved in stimulating nuclear gamma radiation is described. (author). 20 refs.; 2 figs.

Energy Technology Data Exchange (ETDEWEB)

A 38 year old male dentist developed an oligodendroglioma of the left medial temporal lobe and parasellar region 12 years after radiotherapy with 6600 rads for acromegaly. The 30 cases of radiation-induced gliomas reported in the English literature are reviewed and analysed. The criteria for defining radiation-induced tumours of the central nervous system are proposed as follows: the tumour has a long quiescent ''latency period'', a location in the previously irradiated field, a verified histological difference from a primary condition, and does not arise from a primary condition associated with a genetic syndrome such as neurofibromatosis or tuberous sclerosis. The reported case fulfilled these criteria but appears to be the only reported radiation-induced oligodendroglioma.

International Nuclear Information System (INIS)

The long-term survival of certain patients after treatment with radiation or chemotherapeutic agents has allowed the realization that agents that effectively control cancer in the human subject may also possess an oncogenic potential, resulting in secondary malignancies in a significant proportion of surviving patients. A quantitative assessment of the oncogenic effects of these agents at a cellular level is important, as is information on conditions and agents that may effectively alter the development of the neoplastic state. Cell culture systems where the neoplastic transformation of cells can be scored after exposure to carcinogens offer powerful tools for evaluating the oncogenic potential of radiation and chemotherapeutic agents.

International Nuclear Information System (INIS)

The reconstruction of coronal and Sagittal Image of Brain C. T. is helpful to diagnosis of Brain. Three Dimensional Reconstruction software package allows to display three dimensional Image clerived from a series of Horizontal, Sagittal and Coronal Brain C. T. images. It useful in determine approach of operation, to define portals of deep radiation therapy.

International Nuclear Information System (INIS)

Purpose: To evaluate the outcomes of patients with Ewing's sarcoma family of tumors (ESFT) treated with modern radiotherapy techniques with MRI along with optimal chemotherapy. Methods and Materials: The records of all 60 patients with ESFT who received radiation to the primary site between 1990 and 2004 were reviewed. All patients received chemotherapy, including vincristine, doxorubicin, cyclophosphamide, ifosfamide, and etoposide. Radiation was used as the sole modality for local control in 31 patients and was given either before (n = 3) or after surgical resection (n = 26) in the remainder. All patients had MRI and CT scan-based treatment planning, and 43% received intensity-modulated radiation therapy. Radiation doses ranged from 30 Gy to 60 Gy (median, 51 Gy), and 35% received hyperfractionated radiotherapy. Results: Median age was 16 years (range, 2-40 years). Because of ...

International Nuclear Information System (INIS)

Various particle-photon or beam-wave interactions are discussed. To be of use as intense radiation sources, it is necessary that these interactions produce coherent radiation. The free electron laser (FEL), developed on the basis of undulator radiation, is the result of many years of interaction between physics and technology. It has many features, such as continuous tunability over a wide wavelength range, excellent optical quality, high power and short pulse capability, and thus has many potential applications. FEL development in China and abroad are mentioned and the Beijing FEL presented to illustrate the physics and technology involved in an FEL project.

Energy Technology Data Exchange (ETDEWEB)

Investigations of superdense compression touch on such problems as ultrahigh-frequency oscillations of matter in the generation of gravitational waves, the powerful pumping of hard coherent radiation, and the laboratory simulation of stellar interiors. This paper reviews the theory of supercompression and discusses some experiments involving multifoil collision supercompression.

Science.gov (United States)

PMID:6840598

International Nuclear Information System (INIS)

Megavoltage photon intensity-modulated radiation therapy (IMRT) is typically used in the treatment of prostate cancer at our institution. Approximately 1% to 2% of patients with prostate cancer have hip prostheses. The presence of the prosthesis usually complicates the planning process because of dose perturbation around the prosthesis, radiation attenuation through the prosthesis, and the introduction of computed tomography artifacts in the planning volume. In addition, hip prostheses are typically made of materials of high atomic number, which add uncertainty to the dosimetry of the prostate and critical organs in the planning volume. When the prosthesis is bilateral, treatment planning is further complicated because only a limited number of beam angles can be used to avoid the prostheses. In this case study, we will report the observed advantages of using noncoplanar beams in the delivery of IMRT to a prostate cancer ...

International Nuclear Information System (INIS)

In this paper the measurements of radon-222 concentration in the air of Kowary Radon Inhalatorium in the vicinity of Jelenia Gora, Lower Silesia, Poland, performed by Radiation Protection and Radiobiology Department of National Institute of Hygiene in Warsaw, have been presented. For the measurements the integration method with the application of charcoal canisters have been used. The radon concentration was found within the very broad ranges from about 4 to 420 kBq m"-"3 depending of the season of the year. Basing on the radon concentration measurements during the inhalation therapy session and taking into account the equilibrium factor of 0.8 the doses to the bronchi of the patients in range from 1.2 to about 204 mSv (0.12-20.4 rem) have been assessed. The majority of patients (ca. 76%) received the doses between 115 and 204 mSv. (author)

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Subcutaneous involvement frequently occurs in maxillary sinus carcinoma. Radical resection does not include removal of the skin at risk. In standard postoperative wedge-pair treatment plans, the surface dose is dependent upon beam weighting, beam energy, and patient contour. Thermoluminescent dosimetry (TLD) measurements were performed to evaluate the surface dose of patients undergoing postoperative irradiation of maxillary sinus carcinoma following primary resection. When 60 Gy was delivered to isocenter with a 45 degrees wedge pair and 6 MV photons with 1 cm bolus, the subcutaneous tissues at risk received {approximately} 30 Gy. Based upon presented TLD measurements, supplemental electron beam therapy to the subcutaneous tissues if primarily involved should be considered.

International Nuclear Information System (INIS)

The virucidal effect of _6_0Co gamma radiation was studied in cell culture medium and in liquid swine manure involving the most important porcine viruses that can be spread by liquid manure. The radiation doses (20 kGy and 30 kGy) were determined in preliminary experiments employing a porcine enterovirus from the serogroup 1 (Teschen group). In the main experiment, the following viruses were employed: swine vesicular disease (SVD) virus, type C foot-and-mouth disease (FMD) virus, a field strain of Aujeszky's disease (AD) virus, transmissible gastroenteritis (TGE) virus, as well as bovine viral diarrhoea (BVD) virus. The latter strain served as a model for hog cholera virus. The results of the experiments indicate that safe disinfection of the virus infected liquid swine manure by ionizing radiation requires a radiation dose of 30 kGy. (author).

International Nuclear Information System (INIS)

This chapter is an overview of total-ionizing-dose and single-event hardening techniques and should be used as a guide to a range of research publications. It should be stressed that there is no clear and simple route to a radiation-tolerant silicon integrated circuit. What works for one fabrication process may not work for another, and there are many complex interactions within individual processes and designs. The authors have attempted to highlight the most important factors and those process changes which should bring improved hardness. The main point is that radiation-hardening as a procedure must be approached in a methodical fashion and with a good understanding of the response mechanisms involved.

International Nuclear Information System (INIS)

In the context of radiation protection for both workers and the population in general, natural sources of radiation, and in particular radon gas and its short-life decay products assume great importance. In particular, workers in thermal spas can easily be exposed to a level of radon radiation and its decay products comparable to those in uranium mines, though often these workers are unaware of the danger. The main source of radon in thermal baths is the thermal water itself, coming as it often does from deep springs, and this can produce high radon concentrations which are left in those areas in which therapy is carried out. Another factor which cannot be overlooked is the radioactive content of thermal mud, often matured for long periods by contact with thermal water. Thermal cures, though varying slightly from site to site, consist principally of mud cures, hydro-therapy and ...

International Nuclear Information System (INIS)

Based on the practical condition of the plant and in reference to advanced management experiences worldwide, Daya Bay Nuclear Power Plant has established its own peculiar management system for radiation protection management and ALARA implementation. The characteristics of the system are: radiation protection training to all workers, active involvement of all managers and staffs, and whole process safety control to maintenance activities. The management philosophy of 'workers are responsible for their own radiation safety' is adopted in the plant. A strict, formalized and systematic whole staff radiation protection training, evaluation, authorization and periodically refreshing mechanism had been established and executed in the plant. In the organizational point of view, the responsibilities of line managers were specified in plant procedures, ALARA coordination organization on ...

British Library Electronic Table of Contents (United Kingdom)

Objective The aim of this study was to analyze the clinical results of our adaptive radiation therapy scheme of a two-step intensity-modulated radiotherapy (IMRT) method for nasopharyngeal cancer (NPC) at Kinki University Hospital. Methods Between 2000 and 2007, 35 patients with Stage I-IVB NPC treated by IMRT were included. For all patients, treatment-planning computed tomography was done twice before and during IMRT to a total dose of 60-70 Gy/28-35 fractions (median 68 Gy). Chemotherapy (cisplatin 80 mg/m2/3 weeks x 1-3 courses) was given concurrently with IMRT for 31 patients. Results The 3- and 5-year overall survival rates for the 31 patients treated with concurrent chemotherapy were 88% and 83%, respectively. The 3- and 5-year loco-regional control rates for the 31 patients were 93%...

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This report summarizes the major activities and accomplishments of the Idaho National Engineering and Environmental Laboratory (INEEL) Advanced Radiotherapy Research Program for calendar year 2001. Applications of supportive research and development, as well as technology deployment in the fields of chemistry, radiation physics and dosimetry, and neutron source design and demonstration are described. Contributions in the fields of physics and biophysics include development of advanced patient treatment planning software, feasibility studies of accelerator neutron source technology for Neutron Capture Therapy (NCT), and completion of major modifications to the research reactor at Washington State University to produce an epithermal-neutron beam for NCT research applications.

International Nuclear Information System (INIS)

We present the case of a 12-year-old girl who presented with a pathological fracture through a benign-appearing osteolytic lesion that was presumed to represent fibrous dysplasia. The fracture healed, and over the next 2.5 years there was further refracturing and healing with progressive osteolysis. A biopsy was performed and revealed Ewing's sarcoma. The disease was locally controlled by neoadjuvant chemotherapy and radiation therapy. The patient is disease free with excellent function 6 years following the discovery of the lesion. We illustrate and discuss the sequence of events. (orig.)

International Nuclear Information System (INIS)

The radiation properties of the #alpha# emitter "2"1"1At are in favor of its application malignant tumor therapy. As a basis for further investigations the biokinetics of At"-, At x H_2O, At I_2"-, and [At(thio)_2]"+ were determined after i.v. injection into healthy and tumor-bearing mice. The estimation of the ion mobility of the carrier-free compounds allowed the use of uniquely characterized initial compounds. The organ distribution of all species examined was similar to the distribution of astatide. Accumulation was found in the thyroid and other inner organs. (author).

International Nuclear Information System (INIS)

Background. In multiple myeloma 5 different infiltration patterns can be differentiated: 1. Normal appearance of bone marrow, 2. focal involvement, 3. homogeneous diffuse infiltration, 4. combined diffuse and focal infiltration, 5. 'salt-and pepper' pattern with inhomogeneous bone marrow with interposition of fat islands. Methods. For the fast and total acquisition of all patterns a combination of a T1-weighted spin echo sequence and a fat suppression technique is superior. The focal involvement is clearly demonstrated as areas of high signal intensity on e.g. STIR images. Diffuse involvement can be quantified objectively by calculation of the percentage of signal intensity increase after contrast material injection. MRI is superior to X-ray in focal and diffuse involvement. With ultrafast sequences a 'screening' of the whole red bone marrow as for myeloma infiltration is possible. Prognosis. In ...

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Background and purpose: In order to investigate the feasibility, toxicity and antitumor efficacy of hyperfractionated radiation therapy, 37 adult patients with incompletely resected supratentorial low-grade glioma were entered into a phase II study. Materials and methods: The radiation therapy dose was 55 Gy in 50 fractions in 25 treatment days over 5 weeks to the tumor plus a 2-cm margin, with an additional 17.6 Gy given in 16 fractions in 8 treatment days over 1.5 weeks to the tumor plus a 1-cm margin, using 1.1 Gy b.i.d. fractionation with a 6 h interfraction interval. The total tumor dose was 72.6 Gy in 66 fractions in 33 treatment days over 6.5 weeks. Results: The median survival time (MST) for all 37 patients has not yet been attained, while 5- and 7-year survival rates were 75% and 69%, respectively. The median time to tumor progression (MTP) has also not yet been attained, while 5- and 7-year ...

International Nuclear Information System (INIS)

The purpose of the current study was to evaluate the difference in prognostic factors between stage IB and II uterine cervical carcinoma patients treated with postoperative radiation therapy. Between May 1988 and May 1998, a total of 94 patients including 47 patients with stage IB and 47 patients with stage II uterine cervical carcinoma were treated with postoperative radiation therapy at Tokyo Metropolitan Komagome Hospital. All patients were treated with 10 MV X-rays using an anterior-posterior parallel opposed field which covered the whole pelvis. Fractionation was 2 Gy per day, five fractions per week, to a total dose of 50 Gy. The 5-year overall survival rates of stage IB and II were 89.4% and 79.3%, respectively. In multivariate analysis for all patients, lymph node status, histology, and surgical margin status were recognized as prognostic factors. Limited to stage IB patients, lymph node status ...

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In this updated second edition, the order of contents of the textbook has been reorganized. It has been divided into main parts: Basic Science and Clinical Nuclear Medicine. Basic Science, Part I, encompasses basic physics, radiation protection, interaction of radiation with matter and radiation detection, imaging, nuclear pharmacy, and radiation biology. Part II, Clinical Nuclear Medicine, covers the central nervous system, bone, gastroenterology (liver/spleen), cardiovascular system, pulmonary system, genitourinary system, thyroid and endocrine systems, gallium studies, radioassay, hematology, and therapy. The total number of pages of the current edition is increased to 250 from the 213 of the first edition but there are fewer questions because those in the basic science area have been carefully selected to 60 of the original 98 questions. Compared with the previous edition, there ...

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Background. In multiple myeloma 5 different infiltration patterns can be differentiated: 1. Normal appearance of bone marrow, 2. focal involvement, 3. homogeneous diffuse infiltration, 4. combined diffuse and focal infiltration, 5. 'salt-and pepper' pattern with inhomogeneous bone marrow with interposition of fat islands. Methods. For the fast and total acquisition of all patterns a combination of a T1-weighted spin echo sequence and a fat suppression technique is superior. The focal involvement is clearly demonstrated as areas of high signal intensity on e.g. STIR images. Diffuse involvement can be quantified objectively by calculation of the percentage of signal intensity increase after contrast material injection. MRI is superior to X-ray in focal and diffuse involvement. With ultrafast sequences a 'screening' of the whole red bone marrow as for myeloma ...

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Data are presented to support the hypothesis that the initial step in the morphologic transformation of irradiated rodent (BALB/3T3) cells is a frequent cellular event involving a large fraction of the irradiated population. This process appears to involve DNA damage, but not to represent a targeted mutation in specific structural gene(s). Morphologic transformation and immortalization appear to be distinct steps in the overall process of transformation. In contradistinction to rodent cells, immortalization is a very rare event in human diploid cells which is induced at extremely low frequencies. The hypothesis is presented that immortality develops among clones of cells bearing stable chromosomal rearrangements which emerge during the proliferation of a population of radiation damaged cells.

International Nuclear Information System (INIS)

As a series of estimations of population doses and of risk estimates from medical exposures in Japan, the malignancy significant dose (MSD) and the fatal malignant risk from beam therapy were estimated based on a nationwide survey of radiotherapeutic treatments, using a malignancy significant factor and a weighting factor determined from the data on the cancer mortality among the atomic bomb survivors in Nagasaki. The effective dose was defined as a sum of the product of the weighting factor and the organ or tissue doses with respect to the malignant diseases. The organ or tissue doses were determined with ionization chambers placed at the positions of their center in a MixDp-phantom simulated lung tissues by a block of cork, using a telecobalt unit, a conventional X-ray unit and a medical linear accelerator. The organ or tissue doses were categorized into three dose components; namely 1) dose from useful beams; 2) scattered radiation dose from ...

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Ovarian function was evaluated in 11 women 16 to 43 years of age at treatment who received doxorubicin, cyclophosphamide, and high doses of methotrexate with or without radiotherapy in adjuvant therapy of soft tissue sarcoma. Five women (16-33 yr old) who received chemotherapy alone or combined with radiotherapy only at sites distant from the ovaries (chest wall, thigh, and leg) had minimal menstrual irregularities or temporary cessation of menses during therapy; cyclic menses returned promptly after therapy. Gonadotropin levels (expressed as means +/- SD) (follicle-stimulating hormone (FSH), 10 +/- 15 mlU/ml; luteinizing hormone (LH), 10 +/- 4 mlU/ml) and 17 ..beta..-estradiol (E/sub 2/) levels (means +/- SD, 208 +/- 147 pg/ml) were normal. By contrast, 4 older women (ages 36-43 yr) who received similar treatment developd persistent amenorrhea with postmenopausal levels of gonadotropin (FSH, 109 +/- 29 mlU/ml; LH, 72 +/- ...

International Nuclear Information System (INIS)

This research report discusses the radiation hardening of a commercially available mobile robot, the REMOTEC ANDROS. This hardening effort is culminating in the availability of a megarad hardened mobile platform to access areas in nuclear facilities with extremely high levels of radiation (0.1 to 1 Mrad). These radiation levels may be encountered both during routine repair and monitoring activities and accident situations. The project has completed a phase-I U.S. Department of Energy Small Business Innovative Research contract and is now in a phase-II effort with completion scheduled in early 1995. The research involves the evaluation of the material and electrical components of an ANDROS robot to determine the anticipated radiation hardness of the current production version and evaluation of the components that must be replaced or modified to harden the system to higher ...

International Nuclear Information System (INIS)

During one year more than 40,000 items of information on radiation exposure of personnel involved in the handling of radiation sources and more than 5,000,000 items on irradiation of other people are collected in the authors' laboratory. Considerable progress in assessment of mean annual gonad dose of genetically sifnificant dose was attained by means of an algorithm for a personal computer. This simple and inexpensive system has led to a higher accuracy in the application of protective measures. (author).

KoreaScience (Korea)

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... Massage therapy can help the body release certain chemicals. These chemicals help us relax, improve blood circulation and get ...

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Purpose: To evaluate a simple method for quantification of focal activity in bone scintigraphy (BS). Material and methods: The gamma camera was calibrated using a phantom. Quantitative bone scintigraphy (QBS) was performed on 11 men recently diagnosed with prostate cancer (PCa), for whom routine BS showed involvement of the skeleton. Following endocrine therapy for 4 to 8 months, a second QBS was performed. Changes in QBS values were then compared to changes in serum levels of prostate-specific antigen (PSA). Results: PSA response indicating regression of PCa was accompanied by a decrease in the QBS value in 8 of the 11 patients. The overall mean error of the QBS values was 15%. conclusion: QBS according to this method is a relatively simple procedure that might contribute to objective evaluation of therapeutic effects in skeletal metastases, although its validity must be tested in a larger clinical material.

British Library Electronic Table of Contents (United Kingdom)

Abstract Background- Pemphigus vulgaris is a chronic disease not currently curable. Physical involvement and the impact of chronic therapies can lead patients to changes in psychological and relational areas. Objectives- To provide a measure of psychological distress, dysfunctional investment in one's appearance, and their relationship. Methods- Self-administered questionnaires (ASI, HADS) were given to 74 pemphigus inpatients. Results- Strong associations between psychological distress and dysfunctional investment in one's appearance were observed [adjusted odds ratio (OR) = 7.36, 95% confidence intervals (CI) 1.20-45.11; OR 5.38, 95% CI 0.81-35.87, respectively, for appearance stereotyping and body-image vulnerability], together with a perceived high disease severity (OR 6.03, 95% CI 1.9...

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Portal verification images were generated from the photon contamination in electron beams produced by a linear accelerator during treatment of patients receiving high-energy electron radiation therapy (8-14 MeV). An experimental storage phosphor system was used to record the images and display them on laser-printed film. Images were obtained from four or more treatment fractions from 21 cases of head and neck cancer. Precision in field placement was estimated by determining the position of a selected anatomic landmark relative to the center of the field for each series of images. The average standard deviation in the field-position measurements was 3.8 mm. Several procedural problems were also detected and corrected after review of the verification images. The results indicate that the emphasis placed on monitoring and control of field-positioning error in high-energy electron treatments should be similar to the emphasis placed on this aspect ...

International Nuclear Information System (INIS)

Background: the authors report on the conception and first clinical application of a donut-shaped high-dose configuration for proton therapy (PT). This approach allows one to intensify target volume dose coverage for targets encompassing a critical, dose-limiting structure - like here, the cauda equina -, whilst delivering minimal dose to other healthy structures surrounding the target, thereby reducing the integral dose. Methods and results: intensity-modulated PT methods (IMPT) for spot scanning were applied to create and deliver a donut-shaped high-dose configuration with protons, allowing treating > 75% of the target with at least 95% of the prescribed dose of 72.8 CGE, whilst restricting dose to the cauda equina to 60-65 CGE. Integral dose was lower by a factor of 3.3 as compared to intensity-modulated radiotherapy with photons (IMXT). Conclusion: IMPT and spot scanning technology allow a potentially clinically useful approach which is also applicable to ...

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Experiments were carried out on mice and the subjects irradiated for cancer therapy to evaluate the protective efficacy of a Chinese medicinal herb-compound (CMHC). The lethality and the degree of leucopenia caused by radiation in mice medicated with CMHC were significantly less in comparison with control mice (p less than 0.01 and p less than 0.001, respectively). CMHC significantly improved the WBC and the thrombocytes in irradiated workers (p less than 0.01 and p less than 0.001, respectively). The WBC count of 40 patients under radiotherapy while treated with CMHC recovered from 3450 +/- 77/c.mm to 5425 +/- 264/c.mm (p less than 0.001); whereas, in the control group, without any medication, the WBC count dropped significantly (p less than 0.001). Our results revealed the applicabilities of CMHC in protection against radiation damage in spaceflight and in other fields.

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The proton beam has an advantage of the sharp dose falloff in dose distribution called Bragg peak while conventional radiation therapy modalities such as photons exhibit considerable amount of exit dose. To take advantage of this property it is important to know the exact location of the distal dose falloff. An error can cause overdose to the normal tissue or underdose to the tumor volume. The only way of finding out the dose distribution in-situ in particle therapy is to measure the gammas produced by nuclear reactions with tissue materials. Two kinds of gammas can be used: one is prompt gamma and the other is coincident gamma from the positron-emission isotopes. We chose to detect prompt gammas, and developed a prompt gamma scanning system (PGS). The proton beams of the proton therapy facility at National Cancer Center were used. The gamma distribution was compared to the dose distribution measured by ...

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The purpose of this note is to provide guidance to those who have duties under the Health and Safety at Work Act and other relevant legislation. It gives guidance on the practical application of legislation, concerning radiotherapy equipment. Two particular issues arise out of the requirements of Regulation 33 of the Ionising Radiations Regulations 1985 (IRR85) in relation to equipment which is used for medical exposures. These are the requirement to select, install and maintain this type of equipment in such a way that it is capable of restricting, so far as reasonably practicable, the medical exposure of any person where this is compatible with the intended clinical purpose, including the need to ensure that equipment used for radiotherapy is properly calibrated, and the requirement to notify the Health and Safety Executive (HSE) when an incident occurs involving a malfunction or defect in any 'radiation ...

International Nuclear Information System (INIS)

Radiation technology offers a very wide scope for utilisation and commercial exploitation in various field. All over the world, this technology is being favourably considered for different applications like radiation sterilisation of medical products, preservation of food by controlling the physiological processes for extending shelf-life and eradication of microbial and insect pests, radiation processing of polymeric materials and treatment of sewage sludge. Bangladesh Atomic Energy Commission has taken radiation processing programmes in a big way right from its inception. This paper describes the studies carried out by various research groups in Bangladesh Atomic Energy Commission mainly using Cobalt-60 gamma radiation. The investigation covers medical sterilisation, food preservation and development and modification of polymeric materials by gamma radiation. ...

International Nuclear Information System (INIS)

The Coordinated Research Project is a topical collection of research agreements and contracts. The research contracts are awarded with financial support of about 10-20% of the total contract cost. Among the activities of the project is the organization of consultant group meetings and workshops involving several international experts and representatives of users and developers of border radiation monitoring equipment. The project also supports in coordinating the development of equipment and techniques for up-to-date border monitoring and in establishing of a process for providing nuclear forensics support to member states

International Nuclear Information System (INIS)

A multi-group neutron-gamma cross-section library in DTF-IV format is supplemented with electron production matrix to generate a coupled neutron-gamma-electron library. This is realized by estimating the contributions from Compton scattering, pair production and photoelectric effect to the electron production cross-sections. A novel application of this new library, which involves transport of neutrons, gammas and electrons, for estimating the Compton current due to a pulse of radiation in air is discussed.

International Nuclear Information System (INIS)

Neurotensin (NT) and its high affinity receptor (NTR1) are involved in several neoplastic processes. Thus, NT-based radiopharmaceuticals are potential tracers for targeted diagnosis and therapy of NTR-positive tumours. A new analogue based on NT(8-13), NT-XIX, with the three enzymatic cleavage sites stabilised, was synthesised and tested. The synthesis was performed by Boc strategy. Labelling with "9"9"mTc/"1"8"8Re was performed using the tricarbonyl technique. Metabolic stability was tested in vitro and in vivo. NT-XIX was further characterised in vitro in HT-29 cells and in vivo in nude mice with HT-29 xenografts. NT-XIX showed much longer half-lives than non-stabilised analogues. Binding to NTR1 was highly specific, although the affinity was lower than that of natural NT. Bound activity rapidly internalised into HT-29 cells and 50% remained trapped after 24 h. In the time-course biodistribution, the highest uptake was found in the tumour at ...

International Nuclear Information System (INIS)

The main problems arising in decommissioning nuclear-powered submarines (NPS) relate to choosing a concept of handling reactor compartments followed by handling technology development. Reactor compartments (RC) are characterized with extremely space-saving or integral layout of large-size power equipment and systems, restricted access for dismantling, high radiation dose rates in a number of bays of RC. The above RC features pose a problem to find optimum option of RC utilization which on the one hand would be the most cost efficient, and the safest as possible on the other, i.e. dose commitments of personnel involved should be minimum, and effect on population and environment should be negligible. The main radiation factors specifying safety in RC handling at any decommissioning stage are as follows: (1) total radioactivity integrated in reactor facility (RF); (2) distribution of this radioactivity through RF equipment and ...

Science.gov (United States)

B-cell Chronic Lymphocytic Leukemia; Nodal Marginal Zone B-cell Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Splenic Marginal Zone Lymphoma; Waldenstrom Macroglobulinemia

British Library Electronic Table of Contents (United Kingdom)

The aim of this study was to evaluate the differences in accuracy of dose calculation between 3 commonly used algorithms, the Pencil Beam algorithm (PB), the Anisotropic Analytical Algorithm (AAA), and the Collapsed Cone Convolution Superposition (CCCS) for intensity-modulated radiation therapy (IMRT). The 2D dose distributions obtained with the 3 algorithms were compared on each CT slice pixel by pixel, using the MATLAB code (The MathWorks, Natick, MA) and the agreement was assessed with the gamma function. The effect of the differences on dose-volume histograms (DVHs), tumor control, and normal tissue complication probability (TCP and NTCP) were also evaluated, and its significance was quantified by using a nonparametric test. In general PB generates regions of over-dosage both in the l...

International Nuclear Information System (INIS)

Boron neutron capture therapy (BNCT) trials for human glioma (glioblastoma multiform) were initiated September 1994 at the Brookhaven National Laboratory (BNL). Patients are given p-boronophenylalanine-fructose (BPA-F) intravenously as the boron carrier followed by exposure to the epithermal-neutron beam at the Brookhaven Medical Research Reactor (BMRR). The initial phase of the study is to determine safety and toxicity of the drug and irradiation procedure. The epithermal-neutron beam was developed in a joint effort by BNL and Idaho National Engineering Laboratory (INEL) researchers. For the human trials, treatment planning and radiation dose estimation is performed using the BNCT-Rtpe and the rtt-MC computer codes developed by the INEL BNCT program. This paper discusses our initial experience using these treatment planning codes for human subjects. The basic principles of BNCT have been previously documented.

International Nuclear Information System (INIS)

This introductory paper surveys potential sources of electric magnetic, and electro-magnetic fields. Various cases are discussed to exemplify the total frequency range: nuclear magnetic resonance tomography, high-voltage transmission lines, transformer stations, effect lighting balls, military transmitters, transmitter towers of the Postal Services and other operators, mobile radiotelephone equipment, large broadcasting transmitters, radar radiation, high-frequency heat therapy. There is evidence suggesting that electric, magnetic and electro-magnetic fields may possibly represent a certain nuisance or health hazard even at field strength occuring in equipment used for every-day-life purposes, with an emphasis on their possible actions and effects in children and adolescents. The author discusses, in conclusion, the aerial equipment ordinance issued by Lower Saxony. (Uhe).

British Library Electronic Table of Contents (United Kingdom)

Adaptive radiation therapy for liver cancer has the potential to reduce normal tissue complications and enable dose escalation, allowing the potential for tumor control in this challenging site. Using adaptive techniques to tailor treatment margins to reflect patient-specific breathing motions and image-guidance techniques can reduce the high dose delivered to surrounding normal tissues while ensuring that the prescription dose is delivered to the tumor. Several treatment planning and delivery techniques have been developed for use in the liver, including a margin to encompass the full breathing motion, mean position techniques, which evaluate the probability of tumor location during breathing, breath hold, gating, and tracking. Patient selection, clinical workflow, and quality assurance m...

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Office Moves Involving Network Equipment

International Nuclear Information System (INIS)

The interest for medicinal plants has raised again in the last decades, after overcoming a declination period caused by the advances in the researches and development of the synthetic drugs industries. This growing interest has been stimulated mainly by searching cheap and accessible alternative therapies. However, in order to have natural products based treatment in an efficient and safety way, it is necessary to guarantee the plant authenticity, finding adulterations and to assure a low level of microbiological contaminations to avoid damages to consumer's health. The decontamination method should be chosen for eliminating or reduce the microorganisms level without loss of the plant active constituents that would destroy its therapeutic action. At the present work, the possibility of using #gamma# and X electromagnetic radiations to sterilize a Brazilian medicinal plant (Maytenus aquifolium Martius, Celastraceae), which shows anti-ulcer ...

International Nuclear Information System (INIS)

Perforated thermoplastic masks are used to provide patients immobilization. This procedure inserts a material in the path of the radiation beam, that attenuates and modifies the beam fluence and flatness. The present study evaluates the increase in skin dose as a result of using thermoplastic masks. Relative doses were measured on the surface of a solid water phantom, in the presence and absence of masks. These masks were stretched according to deformation patterns observed in clinical routine. The measurements were obtained with a plane-parallel chamber (Markus type 23343) and radiochromic film (EBT Gafchromic) for 6MV X-rays from a linear accelerator, and for a radiation beam from a cobalt therapy unit. The results showed that thermoplastic masks, whose thickness varied between 2 and 3 mm, increased the dose on the surface by a factor of 3. Due to the variations in the skin dose distribution, clinical procedures were ...

International Nuclear Information System (INIS)

Accurate dose calculation in radiation treatment planning is most important for successful treatment. Since human body is composed of various materials and not an ideal shape, it is not easy to calculate the accurate effective dose in the patients. Many methods have been proposed to solve inhomogeneity and surface contour problems. Monte Carlo simulations are regarded as the most accurate method, but it is not appropriate for routine planning because it takes so much time. Pencil beam kernel based convolution/superposition methods were also proposed to correct those effects. Nowadays, many commercial treatment planning systems have adopted this algorithm as a dose calculation engine. The purpose of this study is to verify the accuracy of the dose calculated from pencil beam kernel based treatment planning system comparing to Monte Carlo simulations and measurements especially in inhomogeneous region. Home-made inhomogeneous phantom, Helax-TMS ver. 6.0 and Monte ...

International Nuclear Information System (INIS)

This paper is a progress report on the role of radiation therapy (RT) in local tumor control and the decreased incidence of pulmonary metastasis in 251 patients entered in the Intergroup Ewing's Sarcoma Study. All were followed for more that 1 year, and their RT records were reviewed. Doses to the primary tumor in the range of 4,500--6,500 rad were administered over approximately 5 to 6 weeks in combination with 4 drugs, i.e., vincristine (VCR), dactinomycin (DAC), cyclophosphamide (CY), and adriamycin, or only the first 3. One group of patients received the 3 drugs and bilateral pulmonary irradiation (approximately 1,500 rad in 2 wk). Preliminary analysis showed a local primary tumor control of approximately 90%. Patients with lesions in the pelvis and humerus had local failure rates of 13% (7 of 54) and 21.4% (6 of 28), respectively. The treatment groups differed significantly in the incidence of pulmonary metastasis. Patients treated with ...

International Nuclear Information System (INIS)

Background and purpose: the recent RTOG guidelines for future clinical developments in gynecologic malignancies included the investigation of dose escalation in the paraaortic (PO) region which is, however, very difficult to target due to the presence of critical organs such as kidneys, liver, spinal cord, and digestive structures. The aim of this study was to investigate intensity-modulated radiotherapy's (IMRT) possibilities of either increasing, in a safe way, the dose to 50-60 Gy in case of macroscopic disease or decreasing the dose to organs at risk (OR) when treatment is given in an adjuvant setting. Material and methods: the dosimetric charts of 14 patients irradiated to the PO region at the department of radiation oncology, university hospital of Liege, Belgium, in 2000 were analyzed in order to compare six-field conformal external-beam radio-therapy (CEBR) and five-beam IMRT approaches. Both CEBR and IMRT investigations were planned to ...

UK PubMed Central (United Kingdom)

BackgroundTransarterial chemoembolization (TACE) therapy is an effective locoregional treatment in hepatocellular cancer (HCC) patients. For early modification of therapy, markers...Full Text Available

International Nuclear Information System (INIS)

Radionuclide bone metastases therapy is a major achievement of nuclear medicine. Development of less radiotoxic and more effective radiopharmaceuticals is therefore a challenge for radiopharmacists and industry. This paper reviews the application of rhenium-188 HEDP as a reactor- or generator-produced nuclide for bone metastases therapy. (author)

Energy Technology Data Exchange (ETDEWEB)

Most plans for the disposition of surplus nuclear materials involve storage in sealed containers where the evolution of gases from reactions of adsorbed water could present both pressure and flammability hazards[l] . Despite efforts such as calcining the material to minimize the water content prior to packaging, both residual moisture and readsorbed water may be present in the final containers . Given the anticipated temperature excursions during transportation and storage, this water may thermally desorb, increasing the pressure, and/or thermally dissociate to produce H2 gas, increasing flammability hazards . In addition, the radiation from the nuclear material may induce radiolysis of the water with the likely products being water vapor, H2, 02 and H2O2. In order to better understand the relative importance of the thermal- and radiationinduced chemistry, we have studied the interactions of water on single crystals of uranium dioxide .

International Nuclear Information System (INIS)

We provide a brief review of our recent results from optically detected magnetic resonance studies of grown-in non-radiative defects in two most important dilute nitride systems-Ga(In)NAs grown on GaAs substrates and Ga(Al,In)NP grown on Si and GaP substrates. These results have led to the identification of defect complexes in the alloys, involving intrinsic defects such as As_G_a antisites and Ga_i self-interstitials. They have also shed light on formation mechanisms of the defects and on their role in non-radiative carrier recombination that is harmful to the performance of potential optoelectronic and photonic devices based on these dilute nitrides.

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The purpose of the study was to optimise the technique employed for AP shoulder and lateral cervical spine examinations following an investigation into image quality, based on clinical assessment, and effective dose, calculated from patient entrance surface dose measurements. A study was therefore conducted in an attempt to determine whether the increased radiation dose to the patient following the introduction of an anti-scatter grid was justified by the level of improvement in image quality. The study, involving 100 patients, was able to demonstrate that the increase in radiation dose to the patient when using an anti-scatter grid for AP shoulder examinations is not justified by the improved image quality. A poor level of inter-rater reliability between the consultants scoring the lateral cervical spine images prevented a firm conclusion from being reached. The fact that all images were of diagnostic quality, however, ...

Energy Technology Data Exchange (ETDEWEB)

Moving out of the scientific community research laboratories, computational fluid dynamics (CFD) software packages are now allowing industrials to analyse and optimize industrial processes involving the use of gases, liquids and even some two-phase fluids. Their attractiveness and their impact stems out from the opportunity they offer to bring insight into an existing unit, or even at the design stage, by displaying the spatial distribution of process relevant variables such as temperature, concentration. The filling of the spacing in between a two-layer window is a simple example. This new opportunity of visualisation is at times an unique way, when the process environment is an opaque one, such as liquid metal flowing into a tundish or when measurements of flows may be a long and tedious work, such as flows within water treatment basins. This environment we are to investigate in order to optimize can also be a harsh one, due to its high temperature level for ...

UK PubMed Central (United Kingdom)

The eye is an easily accessible, highly compartmentalised and immune-privileged organ that offers unique advantages as a gene therapy target. Significant advancements have been made in understanding...Full Text Available

UK PubMed Central (United Kingdom)

1 Recommendations for correct therapy with digoxin from twenty-five sources are reviewed. 2 Some recommendations may be unsuitable for use with high bioavailability...Full Text Available

International Nuclear Information System (INIS)

HT-29 human colon tumor cells growing as spheroids have been evaluated as a model system for measuring the response of human colon tumor cell to antineoplastic agents. HT-29 cells have been capacity to form spheroids up to 1 mm or more in diameter when grown in spinner culture. The multicellular HT-29 spheroids develop hypoxic centers reflecting the cellular conditions found in human cancer treatment, i.e., nutritionally deficient hypoxic cells that are felt to be a significant source of both radiation and chemotherapy clinical treatment failures. Spheroids of increasing size were radiated and then dispersed into single cells for colony survival assay. Compared with irradiated single cell suspensions, the spheroid cells demonstrated a significant increase in radioresistance. Growing spheroids developed a complex radiation survival curve which was variable with respect to size of the spheroid. The drug 5-Fu was studied to ...

International Nuclear Information System (INIS)

A mixture of aminoacids was irradiated by a scattered proton beam, its energy varying from 4 to 6.6 MeV, by doses up to 5 x 10"1"1 proton/cm"2 for studying the potentiality of abiogenic synthesis of biologically important compounds in space. It was ascertained that increase in the radiation dose and reduction of proton energy involve increase in effectiveness both of destruction of the initial aminoacid (tryptophan, tyrosine, glycine) and synthesis of the relevant dipeptide. Essential influence of mineral substrate on abiogenic synthesis of natural nucleotides under the action of diverse energy sources was pointed out

Science.gov (United States)

Leachability of neutron irradiated fly ash is investigated as a method for studying element leaching properties of this material with various leaching media. Quantitative aspects of radiation damage are shown to be minor. Therefore, the technique should be applicable for this purpose. It is further shown that this technique affords significant advantages over the conventional post-leaching analysis with respect to utilization of natural solutions for the investigation of fly ash leachability. However, for a few elements such as Pb, Bi, V, and Al, the various nuclear parameters involved invalidate applicability of the present technique.

International Nuclear Information System (INIS)

Many analytical chemistry methods normally used at the Savannah River site require repetitive procedures and handling of radioactive and other hazardous solutions. Robotics is being investigated as a method of reducing personnel fatigue and radiation exposure and also increasing product quality. Several applications of various commercially available robot systems are discussed involving cold (nonradioactive) and hot (radioactive) sample preparations and glovebox waste removal. Problems encountered in robot programming, parts fixturing, design of special robot hands and other support equipment, glovebox operation, and operator-system interaction are discussed. A typical robot system cost analysis for one application is given.

Energy Technology Data Exchange (ETDEWEB)

The ongoing upgrade of the Los Alamos Free-Electron Laser (FEL) Facility involves the addition of a photoelectric injector (PEI) and acceleration capability to about 40 MeV. The electron-beam and high-speed diagnostics provide key measurements of charge, beam position and profile, divergence emittance, energy (centroid, spread, slew, and extraction efficiency), micropulse duration, and phase stability. Preliminary results on the facility include optical transition radiation interferometer measurements of divergence (1 to 2 mrad), FEL extraction efficiency (0.6 {plus_minus} 0.2%), and drive laser phase stability (< 2 ps [rms]). 10 refs.

International Nuclear Information System (INIS)

The total and differential atomic pair-correlation functions of an icosahedral (quasicrystalline) solid were determined for the first time, directly by the differential anomalous-x-ray-scattering technique using synchrotron radiation. The observed atomic distances involving uranium atoms in icosahedral Pd/sub 58.8/U/sub 20.6/Si/sub 20.6/ suggest the presence of a quasicrystalline sublattice with vertex decoration. The pair distribution functions in the icosahedral and amorphous phases are similar up to the second-nearest neighbors, or up to 6 A-circle.

International Nuclear Information System (INIS)

Purpose/Objective: The role of programmed cell death (apoptosis) as a cellular response to cancer therapy such as radiation or chemotherapy is the subject of much study, and manipulation of the apoptotic response in tumor cells may be valuable in the treatment of a variety of cancers. Both p53 dependent and independent apoptotic pathways have been identified; p53 is mutated in at least 50 % of human cancers and a majority of radiation resistant tumors contain p53 mutations. This study is designed to examine the induction of programmed cell death in a human colon carcinoma cell line that possesses two mutated p53 alleles. Ionizing radiation alone, or in combination with the chemotherapeutic drug 5-fluorouracil (5-FU), were used to elicit the apoptotic response. This study will focus on whether these treatments can induce a significant apoptotic response in cells that have mutated p53 alleles. Materials ...

International Nuclear Information System (INIS)

Ewing's sarcoma is a small round-cell tumor typically arising in the bones, rarely in soft tissues, of children and adolescents. Ewing's sarcoma has retained the most unfavorable prognosis of all primary musculoskeletal tumors. Prior to the use of multi-drug chemotherapy, long-term survival was less than 10%. The development of multi-disciplinary therapy with chemotherapy, irradiation, and surgery has increased current long-term survival rates in most clinical centers to greater than 50%. In addition, the preferred method of tumor resection has changed; limb salvage has nearly replaced amputation of the affected limb. Limb salvage procedures can be performed in place of amputation without compromising patient survival rates. Recent studies have revealed that the pathognomonic translocations involving the EWS gene on chromosome 22 and an ETS-type gene, which is most commonly the Fli1 gene on chromosome 11, are implicated in more than 95% of ...

Science.gov (United States)

Glioblastoma multiforme is the most aggressive form of human brain tumor, which has no effective cure. Previously, we have demonstrated that overexpression of the C-terminal fragment of the human telomerase reverse transcriptase (hTERTC27) inhibits the growth and tumorigenicity of human cervical cancer HeLa cells. In this study, the therapeutic effect and molecular mechanisms of hTERTC27-mediated cancer gene therapy were further explored in vivo in established human glioblastoma xenografts in nude mice. We showed that intratumoral injection of adeno-associated virus carrying hTERTC27 (rAAV-hTERTC27) is highly effective in reducing the growth of the subcutaneously transplanted glioblastoma tumors. Histological analyses showed that rAAV-hTERTC27 treatment leads to profound necrosis, apoptosis, infiltration of polymorphonuclear neutrophils and reduced microvessel density in the tumor samples. To study the molecular mechanism of rAAV-hTERTC27-mediated antitumor ...

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Bone scintigraphy was performed in 16 men with newly diagnosed prostatic carcinoma before orchiectomy as well as 2 weeks and 2 months after operation. The uptake in the lower thoracic and lumbar vertebrae was registered up to 240 min after injection of /sup 99m/Tc-MDP and was then calculated for each patient and vertebra. The relative standard deviation in measured uptake due to measuring technique was estimated to be +-7%. In eight patients, who had normal bone scintigraphies before orchiectomy, there were no changes in the uptake values after operation. The remaining eight patients had widespread metastatic involvement prior to treatment, six of these patients showed a so-called 'flare phenomenon' in the abnormal vertebrae which means an initial increase in uptake after operation followed by a decreased uptake in response to therapy. One patient had a continuously increased uptake in all the abnormal vertebrae which ...

International Nuclear Information System (INIS)

Full text: Tumour ablation with radiofrequency (RF) energy is a relatively new procedure for the treatment of focal malignant disease. At our institution this is currently being used in the treatment of certain liver and lung lesions with the patients involved being enrolled in clinical trials. The poster describes the technique used at our institution for the placement of the radiofrequency ablation electrode using CT fluoroscopy. Criteria for patient selection are included. Complications from the procedure are described, as well as follow up appearances and results. Our results from the treatment of primary and secondary lesions in the liver correlate well with published literature. Treatment is still not as successful as surgical resection but there is significantly less morbidity. Where this method may be appropriate is when the patient is not a candidate for surgical resection. The treatment of colorectal metastases in the lung shows early promise as a ...

International Nuclear Information System (INIS)

We used computerized tomography (CT) in the study of eight patients with macronodular splenic tuberculosis prior to the microbiological diagnosis. These patients underwent additional CT controls during and after tuberculostatic therapy. All the patients studed presented the acquired immunodeficiency syndrome (AIDS). Splenomegaly and numerosous round, hypodense lesions that showed no contrast uptake were found in all the subjects. Only three patients presented evidence of tuberculosis in plain radiography and/or chest X-ray. Two patients presented abdominal lymph nodes. None of them showed evidence of hepatic lesions or ascites. follow-up CT scans revealed a progressive reduction of the lesions, which eventually disappeared completely, and splenomegaly was considerably reduced. Anthough it is uncommon, we should suspect splenic involvement in tuberculosis if the clinical and radiological contexts are appropriate. CT provides excellent monitoring ...

International Nuclear Information System (INIS)

Full text: An adaptive response is a decreased biological effect induced by a priming radiation dose given prior to a challenge dose. Adaptive responses contradict the linear-nothreshold model of risk estimation. The pKZ1 mouse chromosomal inversion assay is an extremely sensitive assay for studying the mutagenic effect of low dose radiation. A non-linear dose response for chromosomal inversion has been observed in pKZ1 spleen and prostate after a single whole body irradiation with doses between 1?Gy and 10mGy. Doses between 5-10?Gy resulted in an induction in inversions and doses between 1-10mGy resulted in a reduction below endogenous inversion frequency. These results suggest that doses in the 1-10 mGy range cause host responses which overcompensate by not only preventing inversions that would normally occur as a result of the low doses of radiation but also by preventing some of the endogenous inversions that would have ...

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Manned-space missions bring an exposure due to corpuscular radiations of which nature is quite different from what we encounter in the ground environment. In the space environment, many secondaries are produced through interactions of cosmic ray primaries with the spacecraft wall and other surrounding materials. Among this large variety of radiation components in the space, the contribution of neutrons to the radiation exposure of astronauts has remained to be studied. Up to today, efforts to measure neutron dose equivalent have been made using passive detector systems. Considering uncertainties involved in current measurements and estimations of high energy neutrons, and their increasing importance for future manned missions, it is necessary to measure neutron spectrum in the spacecraft under realistic conditions. The neutron spectra have never been measured on board a spacecraft, because the neutron ...

International Nuclear Information System (INIS)

Although low-energy ion radiation has been proven to have a wide range of biological effects and led to fruitful achievements as a new mutagenic source for genetic modification, there still exist some disputes about its mutagenic mechanisms because of its short-penetrating property. In present research, Arabidopsis thaliana transgenic for GUS recombination substrate was used to evaluate the genomic instability induced by irradiations of alpha particle (3.3MeV) and Low-energy-Argon ion (30 KeV). A pronounced effects of alpha particle irradiation to Arabidopsis thaliana seedlings and Argon ion irradiation to seeds on the somatic homologous recombination frequency (sHRF) were reported. The sHRFs increased 1.88-fold and 2.42-fold, respectively, which indicated that the short-penetrating radiation could effectively induce the plant genomic instability in either dry seeds or seedlings with active metabolism. The local alpha particle irradiation of ...

Science.gov (United States)

PMID:17236670

KoreaScience (Korea)

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Science.gov (United States)

PMID:4447072

Science.gov (United States)

... use of water in wound management, such as whirlpool baths, but can be used interchangeably with the ...

KoreaScience (Korea)

Full Text Available

Energy Technology Data Exchange (ETDEWEB)

In radiation therapy with hadron beams, conformal irradiation to a tumour can be achieved by using the properties of incident ions such as the high dose concentration around the Bragg peak. For the effective utilization of such properties, it is necessary to evaluate the volume irradiated with hadron beams and the deposited dose distribution in a patient's body. Several methods have been proposed for this purpose, one of which uses the positron emitters generated through fragmentation reactions between incident ions and target nuclei. In the previous paper, we showed that the maximum likelihood estimation (MLE) method could be applicable to the estimation of beam end-point from the measured positron emitting activity distribution for mono-energetic beam irradiations. In a practical treatment, a spread-out Bragg peak (SOBP) beam is used to achieve a uniform biological dose distribution in the whole target volume. Therefore, in the ...

International Nuclear Information System (INIS)

Stereotactic radiosurgery (SRS) precisely delivers high-dose radiation to a small target (usually less than 3-4 cm in diameter), in a single session with steep dose-fall, employing various radiation methods. SRS provides good tumor control for small brain metastases from various primary cancers, with minimal untoward effects on surrounding normal brain. This excellent tumor control prevents neurological death and maintains good activity of daily life. Although surgery with whole-brain radiation therapy (WBRT) remains an important option for patients with a solitary brain metastasis, SRS with or without WBRT should be considered in patients with a limited number of small tumors and a good prognosis. Many reports, as well as both retrospective and prospective reviews, have shown WBRT before or after SRS to improve local control and reduce new distant lesion emergence. However, upfront WBRT does not ...

Energy Technology Data Exchange (ETDEWEB)

Background and Purpose: In an earlier phase II study, irradiation together with razoxane was shown to improve local control in recurrent rectal cancer. Therefore, the Austrian Society of Radiooncology (OeGRO) initiated a randomized controlled trial in 1992 to compare this combined treatment versus radiation therapy alone. Patients and Methods: Between 1992 and 1999, 36 patients with localized recurrences of rectal cancer were randomized to receive radiotherapy without (group A) or with razoxane (group B). The prognostic variables of the two groups were similar except for a longer median latency period from initial surgery to local recurrence in group A. High-energy photons with daily fractions between 170 and 200 cGy were used. The median total radiation dose was 60 Gy in each group. The patients in group B received a median razoxane dose of 9.6 g (range, 5-12 g). Main outcome measures were local control, overall survival, ...

International Nuclear Information System (INIS)

The aim of this study was to evaluate the differences in accuracy of dose calculation between 3 commonly used algorithms, the Pencil Beam algorithm (PB), the Anisotropic Analytical Algorithm (AAA), and the Collapsed Cone Convolution Superposition (CCCS) for intensity-modulated radiation therapy (IMRT). The 2D dose distributions obtained with the 3 algorithms were compared on each CT slice pixel by pixel, using the MATLAB code (The MathWorks, Natick, MA) and the agreement was assessed with the ? function. The effect of the differences on dose-volume histograms (DVHs), tumor control, and normal tissue complication probability (TCP and NTCP) were also evaluated, and its significance was quantified by using a nonparametric test. In general PB generates regions of over-dosage both in the lung and in the tumor area. These differences are not always in DVH of the lung, although the Wilcoxon test indicated significant differences in 2 of 4 patients. ...

International Nuclear Information System (INIS)

The purpose of this study was to determine the optimal technique for delivering postoperative radiotherapy for vulvar cancer and other tumors requiring treatment of the inguinal nodes. This project compared tumor coverage and normal tissue sparing for the 5 main radiotherapy techniques that are used to treat vulvar cancer. The intensity-modulated radiation therapy (IMRT) plan was undesirable because it resulted in an excessive dose to portions of the central pelvic structures. The photon thunderbird with skin match was unacceptable because it underdosed a portion of the groin region. The electron thunderbird was ideal for thin patients but was not applicable for most patients because of excessive dose to the skin and subcutaneous tissues. The photon through-and-through and the photon thunderbird with deep match were acceptable in most situations. In thin patients, where the depth of the inguinal vessels is less than 3 cm, the electron ...

International Nuclear Information System (INIS)

A method has been developed for calibration of CT-numbers to volumetric electron density distributions using tissue substitutes of known elemental composition and experimentally determined electron density. This information have been used in a dose calculation method based on photon and electron interaction processes. The method utilizes a convolution integral between the photon fluence matrix and dose distribution kernels. Inhomogeneous media are accounted for using the theorems of Fano and O'Connor for scaling dose distribution kernels in proportion to electron density. For clinical application of a calculated dose plan, a method for prediction of accelerator output have been developed. The methods gives the number of monitor units that has to be given to obtain a certain absorbed dose to a point inside an irregular, inhomogeneous object. The method for verification of dose distributions outlined in this study makes it possible to exclude the treatment related variance contributions, ...

International Nuclear Information System (INIS)

In portal images with high energy X-ray (10 MV), it is sometimes difficult to verify the irradiation field because of the low contrast. Especially, in the abdominal and pelvic region, the deterioration of portal image quality is remarkable. To solve this problem, we took portal images using computed radiography (FCR). Also, we develop a technique in which a copper plate (3 mm) and lead foil (0.3 mm) are closely set in the front and rear of the photostimulable phosphor plate (imaging plate), for increased energy absorption. As a result, image quality was very high and we confirmed image improvement using observer performance experiments. We made a special cassette which can closely set metallic plates to imaging plate and load FCR-7000 directly. Therefore, image process becomes simple, and suitable for routine work. In computed radiography, image processing (tone scale modification and edge enhancement) is possible, and is advantageous portal imaging. When PACS is introduced to the ...

International Nuclear Information System (INIS)

... radiation effects RADIATIONS. WOOD-PLASTIC COMPOSITES.

Energy Technology Data Exchange (ETDEWEB)

Background and purpose: the recent RTOG guidelines for future clinical developments in gynecologic malignancies included the investigation of dose escalation in the paraaortic (PO) region which is, however, very difficult to target due to the presence of critical organs such as kidneys, liver, spinal cord, and digestive structures. The aim of this study was to investigate intensity-modulated radiotherapy's (IMRT) possibilities of either increasing, in a safe way, the dose to 50-60 Gy in case of macroscopic disease or decreasing the dose to organs at risk (OR) when treatment is given in an adjuvant setting. Material and methods: the dosimetric charts of 14 patients irradiated to the PO region at the department of radiation oncology, university hospital of Liege, Belgium, in 2000 were analyzed in order to compare six-field conformal external-beam radio-therapy (CEBR) and five-beam IMRT approaches. Both CEBR and IMRT investigations were ...

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The modification of polymers by radiation grafting has been utilized for several decades. The penetrability of gamma rays allows to modify the internal surfaces of porous materials retaining its mechanical properties. In recent years applications of these materials to obtain chromatographic supports and biocatalysts have been reported. In this work, we described the grafting of glycidyl methacrylate (GMA) onto a macroporous polysulfone polymer. Reproducible amount of grafting, from 10% to 60% was obtained by choosing favourable monomer concentration and gamma radiation doses from 6 kGy up. Afterwards, iminodiacetic acid (IDA) and amino phenyl arsine oxide (PAO) were covalently attached to the grafted polyGMA, in correspondence with the grafting degree. Later on, a recombinant histidin-patch thioredoxin protein (HP-rTrx) was immobilized onto this surface by two different ways, involving specific protein orientations. The ...

Energy Technology Data Exchange (ETDEWEB)

The subjects, principles and purpose of the atomic energy law and the radiation protection law are set out, and criminal offences under atomic energy law are outlined explaining the legal terminology applied. The peaceful uses of nuclear energy and radioactive materials are briefly discussed, primarily looking at the hazards involved and the protective role of criminal law principles that have been developed in connection with the atomic energy law and its application in practice. The draft version of the 16th criminal law amendment act - Act to combat environmental delinquency - is discussed, which aims at adoption of all criminal offences under atomic energy law by the Criminal Code. The book furthermore presents considerations about basic features of delinquency under atomic energy and radiation protection law, revealing elements and facts of offences defined, and particular problems resulting thereof. The question ...

International Nuclear Information System (INIS)

The principal mathematical tools frequently available for calculations in Nuclear Engineering, including coupled neutron-gamma radiations shielding problems, involve the full Transport Theory or the Monte Carlo techniques. The Multigroup Albedo Method applied to shieldings is characterized by following the radiations through distinct layers of materials, allowing the determination of the neutron and gamma fractions reflected from, transmitted through and absorbed in the irradiated media when a neutronic stream hits the first layer of material, independently of flux calculations. Then, the method is a complementary tool of great didactic value due to its clarity and simplicity in solving neutron and/or gamma shielding problems. The outstanding results achieved in previous works motivated the elaboration and the development of this study that is presented in this dissertation. The radiation balance ...

Energy Technology Data Exchange (ETDEWEB)

We present a collisional-radiative approach of the theoretical analysis of laser-induced breakdown spectroscopy (LIBS) plasmas. This model, which relies on an optimized effective potential atomic structure code, was used to simulate a pure aluminum plasma. The description of aluminum involved a set of 220 atomic levels representative of three different stages of ionization (Al{sup 0}, Al{sup +} and Al{sup ++}). The calculations were carried for stationary plasmas, with input parameters (n{sub e} and T{sub e}) ranging respectively between 10{sup 13-18} cm{sup -3} and 0.3-2 eV. A comparison of our atomic data with some existing databases is made. The code was mainly developed to address the validity of the local thermodynamic equilibrium (LTE) assumption. For usual LIBS plasma parameters, we did not reveal a sizeable discrepancy of the radiative equilibrium of the plasma towards LTE. For cases where LTE was firmly believed to ...

International Nuclear Information System (INIS)

Full text: DNA rearrangement events leading to chromosomal aberrations are central to ionizing radiation-induced cell death. Although DNA double-strand breaks are probably the lesion that initiates formation of chromosomal aberrations, little is understood about the molecular mechanisms that generate and modulate DNA rearrangement. Examination of the sequences that flank sites of DNA rearrangement may provide information regarding the processes and enzymes involved in rearrangement events. Accordingly, we developed a method using inverse PCR that allows the detection and sequencing of putative radiation-induced DNA rearrangements in defined regions of the human genome. The method can detect single copies of a rearrangement event that has occurred in a particular region of the genome and, therefore, DNA rearrangement detection does not require survival and continued multiplication of the affected cell. Ionizing ...

Energy Technology Data Exchange (ETDEWEB)

By both increasing the optical iris of the video camera and removing the grid in fluoroscopic procedures involved in placement of a Dubbhoff feeding tube, the radiation dose to patients and staff was reduced by five to seven times. An average expected dose to a patient of about 300 mGy per procedure was reduced by two to three times when the grid was removed and by an additional three times when an iris of increased diameter was used. Because Dobbhoff procedures do not involve obtaining a diagnosis, the image degradation was acceptable and did not affect the total exposure times or ability to conduct the procedure. With the grid out, the difference between the mean exposure times of 5.1 minutes in 96 patient studies done with a normal iris opening and 4.0 minutes in 52 studies done with an enlarged iris was not statistically significant. The importance of reducing patient dose is reinforced by the finding that one-third of ...

Wastenet

... Project Details Title: Influence of increasing droplet concentrations on properties of stratocumulus clouds and climate Supervisor: Dr Alan Gadian Funded by: Engineering and Physical Sciences Research Council (EPSRC) Start date: October 2006 My project involves use of the UK Met Office Unified Model (UM) to calculate the global effect of modifying stratocumulus droplet concentrations on the earth's radiation balance, as well as use of ... Publications Latham, J; Rasch, P; Chen, CC; Kettles, L; Gadian, A; Gettelman, A; Morrison, H; Bower, K; Choularton, T (2008) Global temperature stabilization via controlled albedo enhancement of low-level maritime clouds, Philos. Trans. Roy. Soc. A, 366(1882), pp3969-3987. doi:10.1098/rsta.2008.0137 Current Students | Internal ...

International Nuclear Information System (INIS)

Electron beam (EB) processing involves using electrons to initiate polymerization or cross-linking reactions in suitable substrates, thereby enhancing specific physical and chemical properties. A relatively new use of EB processing is now emerging: the production of fibre-reinforced composites. EB curing at ambient temperature has the potential to reduce the residual stresses in an advanced composite, a result of expansion during thermal curing, and to significantly increase the overall cure speed and process throughput. Wood fibres are used as a filler material for various thermoplastics such as polypropylene. EB treatment, combined with selected EB-curable coupling agents, significantly increases the adhesion between the wood fibres and the thermoplastic polymer, resulting in improved material properties. Work to develop both products and processes for the EB curing of fibre-reinforced composites is currently underway at AECL Research. This paper briefly updates ...

International Nuclear Information System (INIS)

Electrodynamic properties of processes involving charged tachyons are considered in connection with the real superluminal Lorentz transformations. These transformations are interpreted without making use of a tachon corridor and so that the interaction of tachyons from subluminal sources with ordinary matter is Lorentz invariant. Transformations of the electromagnetic fields are deduced from the extended principle of relativity. They are necessary in order to obtain the field equations that are satisfied by fields obeying Maxwell equations relative to superluminal inertial frames with respect to subluminal inertial frames. The field equations allow one to get the dependence of the field energy density and its current on the field strengths. The resulting equations are applied in a discussion of plane electromegnetic waves, sent out by a superluminal source. The obtained electrodynamics allows the existence of charged tatric charges do not behave as magnetic ...

International Nuclear Information System (INIS)

Under operational conditions in nuclear power plants, the carbon steel components of the primary and secondary circuits react with high temperature cooling agent forming several iron oxides and oxyhydroxides. These deposits can result in tubes' constrictions, pitting and intergranular corrosion and finally to heat transfer reducing and increasing of radiation fields around the circuits, as well. The descaling process involves the chemical dissolution of the corrosion deposits by means of diluted organic acidic solutions containing usually a carboxylic acid, a reductant and one or more corrosion inhibitors. To evaluate the removing rates of these superficial films two types of methods were used, the gravimetric and potentiodynamic techniques. By correlating the experimental results, we established the chemical composition of descaling solution and two models of mechanisms applicable to our specific conditions. (authors)

Energy Technology Data Exchange (ETDEWEB)

The structure of ammonium azide (NH{sub 4})N{sub 3} was (re-)determined ab initio from x-ray powder diffraction experiment using synchrotron radiation. We tried to detail and comment the different steps involved in the structure determination. The compound crystallize in the orthorhombic Pmna space group (no.53) with a = 8.937(1) A, b= 3.8070(5) A, c = 8.664(1) A, V = 294.79(7) A{sup 3}; Z= 4. It was possible to locate and refine the hydrogen coordinates, in two different approaches, and to establish the H-bonds. The final structural parameters are in good agreement with previous results based on three-dimensional neutron diffraction. (Author)

Energy Technology Data Exchange (ETDEWEB)

Mitotic delay is described as a classical response to radiation; however, circadian rhythmicity in cell division in vivo has not been considered by many authors. The present study investigated the relation between fluctuations reported as mitotic delay and recovery in vivo and circadian oscillations in mitotic index in mouse corneal epithelium. One aspect involved single doses (approximately 600 rad) given to mice at different circadian stages. The normal circadian rhythm in cell division was never obliterated. Inhibition of mitosis was evident but unpredictable, ranging from 6 to 15 hr after irradiation. Recovery was evident only during the daily increase in mitotic index of controls. The classical interpretation of recovery from mitotic delay may be in an in vitro phenomenon not reflecting in vivo responses, which are apparently strongly circadian stage dependent. The second portion of the study demonstrated a dose-response effect on length ...

International Nuclear Information System (INIS)

A number of procedures in diagnostic radiology and cardiology make use of long exposures to x-rays from fluoroscopy units. Although numerous studies have been performed to measure or calculate skin dose from these procedures, there have only been a handful of studies to determine the dose to the other organs. This thesis was focused on devising a method to calculate the absorbed dose to underlying tissues and organs. The work was performed in several stages. First, a commercial convolution/superposition-based treatment planning system used in radiation oncology was modified and complemented to make it usable with the low energies of x-rays used in diagnostic radiology. This required generation of energy deposition kernels in the kilovoltage energy range. The kernels were generated using the EGS4 Monte Carlo system of codes and added to the treatment planning system. The treatment planning system was then evaluated for its accuracy of calculations at low energies ...

Energy Technology Data Exchange (ETDEWEB)

We irradiated proton beams on the ears of rabbits and the Harding-Passey mouse melanoma and observed their morphological change. We used 52 MeV proton beams from the INS-FM cyclotron. We adjusted the energy of the proton beams to be at the plateau part of the Bragg curve, at the half-way point of the Bragg peak, and at the Bragg peak. The amount of radiation was 5000rad in each case. The Harding-Passey mouse melanoma was transplanted into the subcutan of a three week old mouse. In this experiment, we used tumors, the diameter of which grew up to 1.5-2cm in 2-3 weeks after the transplantation. Using the jroscope, we observed both lightly and severely damaged cells. Using proton irradiation with the Bragg peak located at depth of 1mm in the rabbit's ears, we studied the change in the tissue. Irradiated epidermis fell off and was eroded because of radiation damage, but the rear surface of the rabbit's ears was only slightly ...

UK PubMed Central (United Kingdom)

The side effects of cancer therapy on normal tissues limit the success of therapy. Generation of reactive oxygen species (ROS) has been implicated for numerous chemotherapeutic agents including doxorubicin...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundAdolescents have been identified as a high-risk group for poor adherence to and defaulting from combination antiretroviral therapy (cART) care. However, data on outcomes...Full Text Available

UK PubMed Central (United Kingdom)

ObjectivesTo investigate the effect of group cognitive behavioural therapy (CBT) for fatigue self-management, compared with groups receiving fatigue information alone, on fatigue...Full Text Available

UK PubMed Central (United Kingdom)

Current adherence assessments typically detect missed doses long after they occur. Real-time, wireless monitoring strategies for antiretroviral therapy may provide novel opportunities to proactively...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundThe lack of adequate randomized clinical trials (RCT) has hindered identification of new therapies that are safe and effective for patients with primary focal segmental...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundArtemisinin-based combination therapy, currently considered the therapy of choice for uncomplicated Plasmodium falciparum malaria in endemic countries,...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundHerpes simplex virus (HSV) suppressive therapy reduces genital and plasma HIV-1 RNA over periods up to three months but the longer-term effect is unknown.Full Text Available

UK PubMed Central (United Kingdom)

ObjectiveTo evaluate the effect of different concomitant disease modifying antirheumatic drugs (DMARDs) on the persistence with antitumour necrosis factor (anti-TNF) therapies in...Full Text Available

UK PubMed Central (United Kingdom)

Purpose:The risks and benefits of continuing bisphosphonate therapy beyond 5 years in patients with primary osteoporosis have not been well established.Methods:We...Full Text Available

UK PubMed Central (United Kingdom)

Multiple disease-specific systematic reviews on the effectiveness of physical therapy intervention for shoulder dysfunction have been inconclusive. To date, there have been two systematic reviews that...Full Text Available

Medline Plus

... and at that point she had already failed physical therapy, which someone else had prescribed, and so ... MRI, we may try a brief course of physical therapy to see if they feel better, but ...

UK PubMed Central (United Kingdom)

Premature circuit clotting is a major problem in daily practice of continuous renal replacement therapy (CRRT), increasing blood loss, workload, and costs. Early clotting is related to bioincompatibility,...Full Text Available

UK PubMed Central (United Kingdom)

This joint statement was developed by the CMA and the Canadian Pharmaceutical Association, a national association of pharmacists, and includes the goal of drug therapy, strategies for collaboration...Full Text Available

UK PubMed Central (United Kingdom)

Adjuvant therapy aims to prevent outgrowth of residual disease but can induce serious side effects. Weighing conflicting treatment effects and communicating this information with patients is not elementary....Full Text Available

International Nuclear Information System (INIS)

Purpose: Reconstruction of radiation doses for the thoracoabdominal babygram and the abdomen X-ray from radiographic settings and exposure data acquired at Dr. von Hauner's Kinderspital (children's hospital of the University of Munich, DvHK) between 1976 and 2007; comparison of these dose values with values reported in the literature; recommendation of a reference dose value for the thoracoabdominal babygram. Materials and Methods: The data from all X-ray examinations performed since 1976 at DvHK were stored electronically in a database. After 30 years of data collection, the database now includes 305 107 radiological examinations (radiographs and fluoroscopies), especially 1493 thoracoabdominal babygrams and 3632 abdomen X-rays of newborns and young infants. With the computer program PAeDOS, a specific dose reconstruction algorithm was developed. Results: the entrance dose values of thoracoabdominal babygrams and abdomen X-rays in DvHK could be reduced in the last ...

International Nuclear Information System (INIS)

Shielding calculations for neutron-gamma radiation are usually done by using the full Theory of Transport or the Monte Carlo Techniques. After some works based on the Albedo Method, the shielding calculations for neutron-gamma radiation have a reliable tool with great didactical value which shows its clarity and simplicity for the resolution of cases that involve neutrons and photon shielding in nonmultiplying media. The excellent results of these works have motivated the elaboration and the development of this study that will be presented in this dissertation. The balance of a neutronic current entering a shield of two layers considering the coupling neutron-gamma will be determined by the Albedo Method. The shield will be composed of a layer of iron and another one of manganese with 10 cm of thickness each. The arrays of the materials coefficients will be obtained from the ANISN code. ANISN is a one dimensional ...

International Nuclear Information System (INIS)

The development of leukemia and thyroid cancer is characterized by activation of the abl oncogene and ret oncogene, respectively. In order to clarify the relationship between these gene aberrations and radiation, the pro-myelogenous leukemia-derived cell line HL60 and the thyroid cancer-derived cell line 8505C, were irradiated in vitro with 100Gy of X-rays. RNA was then extracted from 10"8 cells of the respective cell lines and examined by the reverse transcription PCR method for rearrangements of abl and ret genes. Five kinds of positive bands were observed in the HL-60 cells irradiated with 100Gy of X-ray. Similarly, six positive bands were also observed in the 8505C cells irradiated with 100Gy. In vitro X-irradiation activation of oncogenes found in radiation induced cancers imply that gene rearrangement by X-rays is involved in the development of malignant tumors. Furthermore, in an experiment to detect ...

International Nuclear Information System (INIS)

German 2006 [1 p.] Germany Karger, Christian Heeg, Peter Jaekel, Oliver

International Nuclear Information System (INIS)

(Dec 1973). United Kingdom Stevenson, AC Medical Research Council, Oxford

International Nuclear Information System (INIS)

An electron accelerator unit is described for electron beam therapy, comprising: a source of an electron beam; means for finally directing at least a portion of the beam to a therapy site, the directing means being mechanically independent of, and electrically isolated from, the source, and having a target area; and means for aligning the source with the directing means, the aligning means comprising means for projecting at least one beam of light from the source toward the target area.