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71.
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   
72.
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   
73.
Although past research has developed scales for the incidence, prevalence, and fear of student-on-student victimization (SSV), little is known about the scaling of perceived risk (i.e., the cognitive appraisal of the chances of experiencing SSV). Hence, this study examined self-report survey data for the perceived risk of SSV as measured in the Adolescent Index for School Safety (AISS). Children in grades 7 through 10 (n=337) in a single Florida public school completed the AISS. Factor analyses using Maximum Likelihood Estimation with Oblimin Rotation identified nine unique factors for perceived risk. Reliability analyses found standardized Cronbach Alphas that ranged from .64 to .91, and seven out of the nine identified scales were above .80, which suggested good to excellent internal consistency. Future research should examine the content validity, construct validity, and predictive validity for the AISS and other self-report surveys of SSV dynamics. This publication was made possible by a grant [#97-MU-FX-KO12 (S-l)] from the Office of Juvenile Justice and Delinquency Prevention (O.J.J.D.P.), United States Department of Justice (U.S.D.O.J.). This grant is administered through the Hamilton Fish National Institute on School and Community Violence at George Washington University. This specific study was developed and implemented by staff at: 1) East Carolina University’s Department of Criminal Justice; and 2) Florida State University’s Center for Educational Research and Policy Studies. All points of view and opinions in this paper are those of the authors and do not necessarily represent the official position or policies of East Carolina University, Florida State University, the Hamilton Fish National Institute on School and Community Violence, the O.J.J.D.P., or the U.S.D.OJ. The authors would also like to thank Dr. Bill Doerner and Jennifer Jolley for their support, editorial feedback, and insightful comments regarding earlier drafts of this paper.  相似文献   
74.
This paper concerning the last 87 malpractice cases referred to the Department of Psychiatry and Law, Menninger Clinic, includes 57 suits against mental health practitioners and/or institutions, and 30 nonpsychiatric suits against general hospitals, surgeons, obstetricians, etc. A patient was available for interview in only 12 percent of the psychiatric cases; in 88 percent we reviewed medical records and consulted with attorneys. In the psychiatric cases the crucial question was whether a generally accepted standard of care was breached. The inherent problems of applying appropriate criteria to standards of care by practitioners and institutions are discussed. In half the psychiatric cases we found no significant deviation from acceptable clinical performance; in half we concluded that negligent practice had occurred. We did see a litigant for evaluation in 90 percent of the nonpsychiatric cases. The main issue involving them concerned harm or disability related to presumed negligence by medical personnel. How we evaluate such cases and apply disability criteria is discussed.  相似文献   
75.
In the current study the objective was to find to what extent a reliable determination of age at death is made possible by establishing the degree of aspartic acid racemization in the dentin of teeth. The results of the investigation of 46 teeth are in agreement with the values found by other authors. The method presented makes a reproducible and accurate estimation of age possible. We intend to elaborate and improve this promising method for determination of age at death. The relevant points are presented here.  相似文献   
76.
One of the remedies sought by state and local officials for the growing burden of federal mandates is a mandate reimbursement law. A major purpose of mandate reimbursement is to deter Congress from imposing excessive costs on state and local governments by making it fully accountable for its actions. The paper begins by extending the economic theory of grants to mandates and reimbursed mandates. It goes on to assess the benefits and costs of mandate reimbursement, and to distinguish mandates that should be reimbursed, should a reimbursement program prove desirable, from those that should not. Then, using the economic theory of grants and mandates, the paper compares reimbursed mandates with two alternatives for accomplishing the same objective, compensating grants and procedural rules. It concludes that the latter are more promising than mandate reimbursement.  相似文献   
77.
This article surveys the voluminous economic literature on commoditybundling. While bundling has been widely studied, the vast majorityof the literature has focused on theoretical treatments of bundlingthat demonstrate a wide range of reasons why firms might engagein bundling. These papers generally contain restrictive assumptions,including assumptions regarding the existence of monopoly insome markets, and the nature of rivalry in others. The modelscontained in these papers also generally suppress the more obviousand ubiquitous reasons firms may use bundling. Moreover, thesemodels have not been subject to robustness checks, nor havetheir assumptions been tested empirically. This review of theeconomic literature generally confirms the US Solicitor General'sview in 3M v. LePage's regarding the underdeveloped state ofthe economics literature and its position that the US SupremeCourt should defer promulgation of antitrust standards for bundling.While the literature has demonstrated the possibility that bundlingcan generate anticompetitive harm, it does not provide a reliableway to gauge whether the potential for harm would outweigh anydemonstrable benefits from the practice. As a result, the widespreadapplication of the antitrust laws to bundling by firms can generatesignificant error costs by erroneously condemning or deterringefficient business practices. In the future, economists shouldseek to expand their understanding of both the anticompetitiveand procompetitive reasons firms engage in bundling. This willentail studying the reasons why bundling is adopted by firmswithout market power, relaxing the assumption of monopoly intheoretical models, and generating testable hypotheses and thedata to test them.  相似文献   
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