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211.
PURPOSE: To compare commercial treatment-planning systems (TPS) for inverse planning (IP) and to assess constraint variations for specific IMRT indications. MATERIAL AND METHODS: For IP, OTP, XiO and BrainSCAN were used and step-and-shoot intensity-modulated radiotherapy (IMRT) delivery was assumed. Based on identical constraints, IP was performed for a prostate, head and neck, brain, and gynecologic case. IMRT plans were compared in terms of conformity/homogeneity, dose-volume histograms (DVHs), and delivery efficiency. For ten patients each of a class of indications, constraint variations were evaluated. RESULTS: IMRT plans were comparable concerning minimum target dose, homogeneity, conformity, and maximum doses to organs at risk. Larger differences were seen in dose gradients outside the target, monitor units, and segment number. Using help structures proved efficient to shape isodoses and to reduce segmentation workload. For IMRT class solutions, IP constraint variations depended on anatomic site. CONCLUSION: IP systems requiring doses as input and having objective functions based on physical parameters had a very similar performance. Constraint templates can be established for a class of IMRT indications.  相似文献   
212.
There is a broad differential for patients presenting with fever, eosinophilia, and pneumonia. We present a case of a 48-year-old man who presented with recurrent fever, pleuritic chest pain, and cough. His medical history was significant for a recent trip to Arizona. A chest X ray showed a right lower lobe infiltrate and CT examination of the chest showed extensive mediastinal lymphadenopathy. Tissue culture from a biopsy specimen of the mediastinal lymph nodes revealed growth of Coccidioides immitis and a diagnosis of coccidioidomycosis was made. He was treated with a total of a 9-month course of itraconazole and has remained disease free for >2 years. This case shows how a careful history and evaluation will direct the clinician to the correct diagnosis.  相似文献   
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BACKGROUND: Cardiac magnetic resonance (MR) images are often reviewed by non-cardiologists who are not trained in the interpretation of regional left ventricular (LV) function. We hypothesized that the use of still-frame parametric MR images of wall motion could aid in the assessment of regional LV function. METHODS: Dynamic, electrocardiogram-gated, steady-state free precession (FIESTA) short-axis images were obtained in 6 to 10 slices in 18 consecutive patients. Each loop was used to automatically generate a still-frame image, in which each pixel is assigned a value equal to the amplitude of cyclic variation in local intensity, resulting in higher intensity in pixels that change between blood and tissue during the cardiac cycle. The dynamic images were reviewed by an expert cardiologist who provided gold standard grades for regional wall motion and by four radiologists. Then the radiologists reviewed and graded the same MR images in combination with parametric images. Grades assigned to each segment in the two sessions were compared with the gold standard. RESULTS: According to expert interpretation, 6 patients had normal wall motion, and 12 had wall motion abnormalities. Parametric images showed a bright band in the area spanned by endocardial motion, with reduced brightness and thickness in areas of hypokinesis. The agreement between the radiologists' grades and the gold standard significantly improved by adding parametric images (from 77% to 81%), which also resulted in reduced interobserver variability (from 52% to 33%). CONCLUSIONS: Still-frame parametric images aid in the assessment of regional wall motion by non-cardiologists who are required to interpret cardiac images.  相似文献   
216.
The Sixth Epilepsy Research Foundation workshop, held in Oxford in March 2006, brought together basic scientists, geneticists, epidemiologists, statisticians, pharmacologists and clinicians to consider progress, issues and strategies for harnessing genetics to improve the understanding and treatment of the epilepsies. General principles were considered, including the fundamental importance of clear study design, adequate patient numbers, defi ned phenotypes, robust statistical data handling, and follow-up of genetic discoveries. Topics where some progress had been made were considered including chromosomal abnormalities, neurodevelopment, hippocampal sclerosis, juvenile myoclonic epilepsy, focal cortical dysplasia and pharmacogenetics. The ethical aspects of epilepsy genetics were reviewed. Principles and limitations of collaboration were discussed. Presentations and their matched discussions are produced here. There was optimism that further genetic research in epilepsy was not only feasible, but might lead to improvements in the lives of people with epilepsy.  相似文献   
217.
Our body houses the various selves we are. It continuously informs us about the position of its limbs, both relative to themselves and relative to the trunk and head. It allows us to feel touch, to reach out and touch others, and to differentiate between passively received and self-delivered touch. It provides us with information about temperature, pressure, and gravity. and it mediates basic sensations, feelings, and emotions, from pain, fatigue, and hunger to relaxation, lust, and ticklish joy. Enabling us to look up to the stars, it even shows us how small we are, how limited in reach, and how alone most of the time. Only our body is constantly present; it is the only object that abidingly stays with us throughout our lives, it is perhaps this continuity that binds together the different components of our self - sensory-receptive, motor-agentive, emotional - and makes us feel that we are one self in one body.All this said, we note that there are various neurological conditions in which the unit y between body and self is thoroughly shaken. We may no longer acknowledge ownership of parts of the body, or we may deny agency over bodily actions. We may feel alienated or spatially separated from our body, or project the experience of touch info objects in extracorporeal space. Although not obligatorily eliciting a morbid reaction, such disintegrations between body and self occasionally induce overt hostility. The present note provides a glimpse into some major types of auto-aggression after body-self fragmentation.  相似文献   
218.
If proven effective, vaginal microbicides and diaphragms will likely be part of a larger HIV prevention model that includes condoms and other prevention strategies. It is, therefore, important to understand how introducing new prevention methods may affect overall patterns of sexual risk behavior. Data presented were collected as part of a safety and feasibility study of ACIDFORM gel with a diaphragm among 120 women in South Africa. Interviews were administered at enrollment and months 1, 3, 5, and 6 of the trial. Focus groups were conducted at trial exit. Frequency of sex increased significantly after enrollment. This increase appears to be owing to perceived protection from HIV and greater sexual pleasure afforded by the gel. Male condom use was high overall but increased significantly from enrollment. Data suggest this is because of increased partner involvement, increased negotiating power afforded by study participation, and provision of free condoms perceived to be of high quality.  相似文献   
219.
Alemtuzumab is a powerful lymphocyte depleting antibody currently being evaluated in solid organ transplantation. This paper describes 5-year results of a single center study of alemtuzumab as induction in renal transplantation. Thirty-three renal transplant recipients received 20 mg alemtuzumab on day 0 and 1, followed by half-dose cyclosporin monotherapy (trough concentration 75-125 ng/mL) from day 3. They were compared in a retrospective contemporaneous-controlled manner with 66 kidney transplant recipients transplanted in the same period and center who received conventional immunosuppression with cyclosporin, azathioprine and prednisolone. In the alemtuzumab group 12% of recipients died compared to 17% in the control group (p = 0.48); likewise graft loss was similar in both groups (21% vs. 26%, respectively, p = 0.58). Incidence of acute rejection was also comparable at 5 years (31.5% vs. 33.6%), although the pattern of rejection was different with 14% patients in the alemtuzumab group experiencing rejection over 1 year post-transplant compared to none in the control group. There was no significant difference between groups in terms of infection or serious adverse events. While acknowledging the limitations of a relatively small single-center study, results suggest that alemtuzumab induction allowed satisfactory long-term patient and graft survival equivalent to that seen with standard triple immunosuppression, while avoiding steroid therapy.  相似文献   
220.
International Journal of Clinical Pharmacy - In order to calculate the minimum sterilization process conditions to obtain the generally accepted sterility level (less than 1·10?6...  相似文献   
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