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201.
Postmortem examination of a former professional basketball player revealed an abnormal heart, most notably a single coronary artery. The literature on single coronary arteries is briefly reviewed, and the possible mechanism which caused the patient's condition is considered. This case is particularly unusual because of the patient's profession, which is so physically demanding.  相似文献   
202.
The fingernail ridge patterns of a pair of identical twins were compared to each other, their parents, and an unrelated subject. The patterns of the twins' nails showed regions of strong similarity but were distinguishable from one another. Fewer similarities were found when comparing the nails to those of the parents and the unrelated control. The twins were shown to be monozygotic by means of DNA profiling. This therefore represents the first demonstration of unique fingernail ridge patterns in subjects shown conclusively to be identical twins. When the fingernail ridge patterns were examined with a scanning electron microscope, the backscattered electron (BEI) images were found to have superior contrast when compared to the secondary electron (SEI) images.  相似文献   
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Congress and the Drug Enforcement Administration have assigned certain psychoactive substances to one of five schedules, based on assumed or demonstrated abuse potential. Although formidable difficulties exist in assessing the hazards of drug use, some of these assignments do not appear consistent with empirical estimates. This mismatch of assignment and abuse potential -possibly due to "radical" political ideology - obscures significant differences in drug effects, and therefore stifles meaningful public participation in evaluating the benefits, risks, and proper use (if any) of available psychoactive substances.  相似文献   
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This paper applies the poliheuristic theory of foreign policy decision making to non-democratic states. Poliheuristic theory asserts that state leaders assign primary importance to their political survival; however, the meaning of "the political" varies dramatically from country to country. Furthermore, the types of actors who hold leaders politically accountable also vary between countries. Consequently, leaders often pursue vastly different means of ensuring their political survival. The author uses the common distinction between single-party, military, and personalist autocracies to show that apparently arbitrary differences in autocratic leaders' political concerns actually vary in systematic and potentially predictable ways. Because this argument is generalized to non-democratic states as a whole, it has important implications for the ways in which democratic states craft their policies toward autocracies.  相似文献   
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