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Esophageal and tracheal fistulas, which occur in 0.05% of medicolegal autopsies, were demonstrated in three cases by a postmortem radiographic technique using silicone rubber/lead oxide as a contrasting medium that vulcanizes at room temperature. In one 83-year-old male, a tracheoesophageal fistula was detected, which had developed after surgical repair of an esophageal rupture caused by a flexible fiberoptic endoscope. In a second case, carcinoma of the esophagus in a 78-year-old male had eroded the trachea and arcus of the aorta creating a fatal tracheoesophagoaortic fistula. In a third case, 55-year-old female developed a tracheobrachicephalic artery fistula as a result of an infiltrating cystic adenocarcinoma of the trachea, resulting in a fatal hemorrhage into the trachea. The results of this study indicate that diagnostic radiologic methods using a vulcanized contrasting medium are useful in supplementing normal dissection in autopsy cases with suspected fistulas of the esophagus or trachea.  相似文献   
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We use data from 1983 and 1985 on the volume of Medicare physician services to analyze whether Medicare's Prospective Payment System (PPS), which resulted in a significant decline in hospital spending, led to a partially offsetting increase in real expenditures for physician services. We also analyze the effect of increases in assignment rates, increasing incomes of the elderly, and other factors on real expenditures during this period. Our main conclusion is that PPS has at most a small positive effect on real physician expenditures. Because people spent less time in the hospital, Medicare physician spending declined; but because of incentives to shift radiology and other services out of the hospital, some of this decline was offset. We also conclude that the sharp increase in Medicare assignment rates over this period, along with the rising incomes of the elderly during this period, contributed to the observed growth.  相似文献   
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This article discusses relevant literature on the potential benefits of sport, recreation, and leisure, and how these benefits relate to rehabilitation of juveniles. Many professionals involved in juvenile rehabilitation believe sport and recreation are beneficial adjuncts to treatment programming; however, it can be difficult to structure sport and recreation in ways that directly correspond to treatment goals. The purpose of this article is to provide insights for professionals working with juveniles on how sport and recreation programming can be an effective means of helping to achieve rehabilitation goals. Attention is given to approaches, particularly the Teaching Games for Understanding model (Bunker & Thorpe, 1982), which can be used to effectively link recreation and sport to the rehabilitation process.  相似文献   
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