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PURPOSE: To assess the clinical utility of X-ray volume imaging (XVI) for verification of bladder radiotherapy and to quantify geometric error in bladder radiotherapy delivery. METHODS AND MATERIALS: Twenty subjects undergoing conformal bladder radiotherapy were recruited. X-ray volume images and electronic portal images (EPIs) were acquired for the first 5 fractions and then once weekly. X-ray volume images were co-registered with the planning computed tomography scan and clinical target volume coverage assessed in three dimensions (3D). Interfraction bladder volume change was described by quantifying changes in bladder volume with time. Bony setup errors were compared from both XVI and EPI. RESULTS: The bladder boundary was clearly visible on coronal XVI views in nearly all images, allowing accurate 3D treatment verification. In 93.5% of imaged fractions, the clinical target volume was within the planning target volume. Most subjects displayed consistent bladder volumes, but 25% displayed changes that could be predicted from the first three XVIs. Bony setup errors were similar whether calculated from XVI or EPI. CONCLUSIONS: Coronal XVI can be used to verify 3D bladder radiotherapy delivery. Image-guided interventions to reduce geographic miss and normal tissue toxicity are feasible with this technology.  相似文献   
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Contaminated poultry meat has been identified as one of the principal foodborne sources of Salmonella. Molecular characterization of Salmonella is important in addressing methods to control this pathogen. Seventy-four retail turkey meat samples were collected from various stores in Fargo, North Dakota in the fall of 2003. Salmonella was recovered from 30 samples using the standard conventional culture method (FSIS, USDA). Isolated Salmonella were characterized by serotyping, pulsed-field gel electrophoresis (PFGE) analysis, plasmid analysis, and antibiotic resistance profiling. Five serotypes were identified among the isolates: Newport (n = 12), Hadar (n = 8), Heidelberg (n = 7), 4,12:nonmotile (n = 2), and Reading (n = 1). XbaI PFGE analysis revealed 13 PFGE types and succeeded in grouping the isolates according to their serotypes. Plasmid profiling identified 5 plasmid types (with 1 or 2 plasmids) among eleven isolates that harbored plasmids. Seventeen isolates were resistant to antibiotics. The Heidelberg serotype showed resistance to multiple antibiotics: 1 isolate had resistance to gentamicin, sulfamethoxazole, and streptomycin, and 6 isolates had resistance to tetracycline, gentamycin, sulfamethoxazole, kanamycin, and streptomycin. The Hadar serotype isolates were resistant to 2 or 3 antibiotics: tetracycline and streptomycin (1 isolate); tetracycline and kanamycin (1 isolate); and tetracycline, kanamycin, and streptomycin (6 isolates). The 4,12:nonmotile serotype isolates showed resistance to tetracycline only. The Newport and the Reading serotypes were susceptible to all 16 of the antimicrobials tested.  相似文献   
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Tegtmeyer  CJ; McCue  FC  d; Higgins  SM; Ball  DW 《Radiology》1979,132(1):37-41
Single and double contrast arthrographic techniques were compared in 951 patinets with suspected meniscal injuries. Exploratory surgery of the knee was performed in 384 of these patients and good clinical follow-up was obtained in 135 patients. In the latter two groups of patients, the single contrast technique was 97% accurate in assessing the medial meniscus and 96% accurate in assessing the lateral meniscus. Double contrast arthrography was 97% accurate in assessing the medial meniscus and 93% accurate in assessing the lateral meniscus. Numerical differences in the results from the two techniques were not statistically significant. Therefore both techniques can be considered equally effective diagnostically.  相似文献   
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Child development hearings, government research, and federal projects are examined to determine whether or not the physically ill child should attend day care. Federal and state standards reveal a wide dispersion of opinion as well as a lack of analytically useful research. The probability of children catching infections and developing serious illness remains the main debate issue as to whether the physically ill child should attend day care. Supporters for inclusion of the physically ill child in day care argue that removing the child from school won't prevent or diminish contagion.  相似文献   
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Spinal epidural angiomatous malformations draining into intrathecal veins   总被引:18,自引:0,他引:18  
Summary Nine angiomatous malformations situated on the outer surface of the dura and one situated in the pelvis, from which draining veins pierced the dura and joined the coronal venous plexus are described. The clinical manifestations and myelographic appearances are similar to those of the majority of intradural angiomatous malformations. This suggests that neurological deficiencies with both types of malformation are usually due to raised venous pressure with secondary ischaemic hypoxia.  相似文献   
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