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Weight loss after gastric bypass procedures has been well studied, but the long-term metabolic sequelae are not known. Data on bone mineral density (BMD), calcium, parathyroid hormone, and vitamin D were collected preoperatively and at yearly intervals after gastric bypass procedures. A total of 230 patients underwent preoperative BMD scans. Fifteen patients were osteopenic preoperatively, and three patients subsequently developed osteopenia postoperatively within the first year. No patient had or developed osteoporosis. At 1 year, total forearm BMD decreased by 0.55% (n = 91; P = .03) and radius BMD had increased overall by 1.85% (n = 23; P = .008); both total hip and lumbar spine BMD decreased by 9.27% (n = 22; P < .001) and 4.53% (n = 31; P < .001), respectively. By the second postoperative year, BMD in the total forearm had decreased an additional 3.62% (n = 14; P<.001), whereas radius BMD remained unchanged. Although total hip and lumbar spine BMD significantly decreased at 1 year, by year 2 both total hip and lumbar spine BMD only slightly decreased and were not significantly different from before the operation. Serum calcium decreased from 9.8 mg/dL to 9.2 during the first year (not significant [NS]) and then to 8.8 (NS) by the second year. Parathyroid hormone increased from 59.7 pg/mL (nl 10-65 pg/mL) preoperatively to 63.1 during year 1 (NS) and continued to increase to 64.7 by year 2 (NS). No difference was noted among levels of 25-hydroxy vitamin D preoperatively (25.2 ng/mL; nl 10-65 ng/mL), at 1 year (34.4), and at 2 years (35.4). Our data indicate that bone loss is highest in the first year after gastric bypass with stabilization, and that, in some cases, there is an increase in bone density after the first year. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation).  相似文献   
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Competitive pressures to achieve a slim body shape may be of importance in the etiology of eating disorders in ballet dancers. This study examines the presence of anorexia nervosa-like symptoms in a group of 49 female ballet students (mean age = 18.9 years, SD ± 1.9). All students were assessed for certain physical (weight and height) and psychological (Eating Attitude Test [EAT]) indices at the start of their academic training year. Thereafter, all subjects who presented with anorexia nervosa-like symptoms (EAT ≥ 30, and/or with current secondary amenorrhea or primary amenorrhea if aged 16 years or over) at the initial assessment, were invited for a semistructured interview (Morgan-Russel scales) to determine their diagnostic status. Another aim of the study was to assess the prognostic implications of a diagnosis of anorexia nervosa in this sample. All subjects previously interviewed were invited for a follow-up assessment at 10 months. Anorexia nervosa could be diagnosed in 2 students (4.1%), whilst another 4 students (8.2%) presented with “partial syndrome” anorexia nervosa. All diagnosed students managed to complete their academic training year. The development and implications of a diagnosis of anorexia nervosa in the ballet students are discussed.  相似文献   
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Copper radionuclides and radiopharmaceuticals in nuclear medicine   总被引:4,自引:0,他引:4  
The chemistry, radiochemistry, radiobiology, and radiopharmacology of radiopharmaceuticals containing copper radionuclides are reviewed. Copper radionuclides offer application in positron emission tomography, targeted radiotherapy, and single photon imaging. The chemistry of copper is relatively simple and well-suited to radiopharmaceutical application. Current radiopharmaceuticals include biomolecules labelled via bifunctional chelators primarily based on cyclic polyaminocarboxylates and polyamines, and pyruvaldehyde-bis(N4-methylthiosemicarbazone) (PTSM) and its analogues. The chemistry of copper, of which only a fraction has yet been exploited, is likely to be applied more fully in the future.  相似文献   
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We measured retinal vessel diameter before and after panretinal photocoagulation in 59 eyes with diabetic retinopathy and moderate to severe optic disk neovascularization. Treatment significantly reduced mean arteriolar and venular diameter. The diameter of the retinal arterioles after treatment correlated significantly with the amount of regression in disk neovascularization. Eyes with large diameter vessels after treatment usually had little or no regression of proliferative retinopathy, whereas regression was more frequently seen in eyes with smaller diameter vessels after treatment.  相似文献   
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