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The common history of drug abuse in adults with an undetermined cause of death has led us to hypothesize that chronic drug abuse increases the risk of sudden death. To begin evaluating this hypothesis, we conducted a retrospective case-control study of 61 decedents whose cause of death remained undetermined following autopsy matched one to one to a control group of pedestrians or passengers killed in motor vehicle collisions. In 21 pairs, the case subject had evidence of drug abuse but the control did not, and in 5 cases the reverse was true. Analysis showed that individuals with an undetermined cause of death are 4.2 times more likely to have evidence of drug abuse than are victims of a motor vehicle collision. 相似文献
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This case-control study investigates the relationship between suicide and wealth in Kansas City, Missouri. House and personal property appraisal data on all victims of suicide from 1998 and 2002 and victims from a control population of deaths reported to the Jackson County Medical Examiner during the same time interval were obtained from the Jackson County Government website. The controls were matched to suicide cases by race, gender, year of death, and age at death (+/- 1 year). Data from the 426 members of each group of suicides and controls indicate that suicide victims were: 1) 77% more likely than controls to have lived in houses rather than in apartments or trailers, 2) more likely than controls to have lived in more expensive houses (mean values dollar 70,143 versus dolllar 61,513 respectively, p = 0.04) and 3) more likely to have killed themselves because of factors other than financial strain (8.0% of suicides showed financial strain). 相似文献
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Gerald M. Steinberg 《Policy Sciences》1985,18(1):79-93
In policy debates concerning large scale R&D efforts, the achievements of the Manhattan and Apollo projects are frequently cited as evidence of Yankee ingenuity and the ability to overcome technical obstacles. In this article, the factors which contributed to the success and failure of large scale crash development projects are analyzed systematically. Successes are distinguished from failures according to two criteria. First, while the successes are marked by parallel development of technological components which began only after the basic scientific and technical obstacles had been overcome and the basic feasibility had been demonstrated, in the failures, parallel development began much earlier. In addition, the successful crash projects, such as the atomic bomb effort and the moon program, were designed to meet static technical goals and did not depend on overcoming countermeasures. The unsuccessful projects, such as the Safeguard ballistic missile defense (BMD) system, failed in the face of changes in Soviet military technology.Using these criteria to analyze the Reagan administration's space-based ballistic missile defense program (SPBMD), the author concludes that despite the claims made by supporters, this R&D effort is not similar to the Manhattan or Apollo projects. Rather, like the Nuclear Airplane and Skybolt missile, parallel developments have begun prior to proof of feasibility, and like the Safeguard BMD, the SPBMD must adapt to countermeasures. 相似文献
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