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排序方式: 共有877条查询结果,搜索用时 15 毫秒
91.
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Healthy male volunteers drank neat whisky in amounts corresponding to 0.51, 0.68, or 0.85 g ethanol/kg body weight in 15-25 min after an overnight (10 h) fast. Urine was collected immediately before drinking and then at 60 min intervals for 7-8 h after intake. The volumes of urine voided were measured and the concentrations of alcohol (UAC) were determined by an enzymatic method. Ethanol-induced diuresis showed large inter-subject variations. The flow of urine was maximum between 60 and 120 min post-drinking when the median rates of production were 117 ml/h (range 55-335), 113 ml/h (range 41-453) and 373 ml/h (range 215-485) for 0.51, 0.68, and 0.85 g ethanol/kg respectively. The output of urine returned to normal (30-60 ml/h) after the peak UAC had passed despite an elevated blood alcohol concentration (BAC). The average amount of alcohol excreted in urine was 0.29 g (S.D. 0.119), 0.44 g (S.D. 0.246), and 1.00 g (S.D. 0.427) after the consumption of 0.51, 0.68 and 0.85 g ethanol/kg respectively. Neither peak diuresis nor the amount of alcohol excreted depended on a subject's age between 20 and 60 years. This work shows that after drinking a moderate dose of alcohol, only 0.7-1.5% of the amount consumed is excreted unchanged in urine. Ethanol-induced diuresis is most pronounced for the first 1-2 h after drinking (rising BAC). The production of urine returns to normal during the post-absorptive state.  相似文献   
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This paper assesses the role of the United Nations in nuclear disarmament in the early postwar period and provides an explanation as to why its contribution was limited. It presents a framework of analysis concentrating particularly on the political organs of the UN. It is a view from within the World Organisation. It emphasises the difficulties the UN encountered in establishing its credentials in dealing with the requirements of the nuclear age. Finally, the paper examines the reasons of the failure of the negotiations which took place between 1945 and 1950.  相似文献   
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Evaluators have often had trouble providing analyses that are of practical use to policymakers. A major reason for this is that evaluators characteristically pay little attention to variables that are politically relevant. The National Institute of Education's evaluation of Title I of the Elementary and Secondary Education act, used extensively by Congress in 1977–1978, provides a clear example of how attention to political concerns can pay off for evaluators in increased utilization of their products.  相似文献   
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Death associated with nitrite ingestion: report of a case   总被引:1,自引:0,他引:1  
The tissue concentrations of nitrite and nitrate found at autopsy of a case of intentional ingestion of nitrite salts have been reported. The percentage of methemoglobin and the serum nitrite concentrations are consistent with those reported for acute overdoses. We conclude that noth nitrite and nitrate salts may be identified in tissues from persons ingesting only nitrite salts and that a significant conversion to nitrate may result from oxidation of nitrite during the conversion of heme iron to Fe3+.  相似文献   
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