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201.
Deoxyribonucleic acid (DNA) was isolated from a number of spongy and compact human bone tissue specimens, and the yield was estimated on a "per milligram of starting tissue" basis. DNA was, in addition, isolated from a number of corresponding blood and bone tissue specimens. Spectrophotofluorometry and ethidium bromide visualization on minigels were used to estimate the quantity and degree of degradation of DNA. The DNA from several blood-bone pairs is shown to give concordant restriction fragment length polymorphism (RFLP) typing results by two different typing protocols with five different single-locus probes. DNA from several additional blood-bone pairs is shown to give concordant results for human leucocyte antigen (HLA)-DQ alpha phenotypes following polymerase chain reaction (PCR) amplification and hybridization to specific allele-specific oligonucleotide (ASO) probes, and for the variable numbers of tandem repeats (VNTR) length polymorphisms 3' to the human apolipoprotein B (APOB) gene following PCR amplification with specific primers and analysis of the products by electrophoresis and ethidium bromide visualization.  相似文献   
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Merit rating for physicians' malpractice premiums: only a modest deterrent   总被引:1,自引:0,他引:1  
Rolph JE 《Law and contemporary problems》1991,54(1-2):Spring 65-Spring 86
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The Equal Employment Opportunity Commission (EEOC) recently issued its final regulations on the Americans with Disabilities Act (ADA). Although the regulations offer some guidance for employers on how to comply with the Act, they fail to provide specific answers to the many complicated compliance questions that will surely arise. Further, the regulations are almost totally silent on certain critical issues related to insurance, workers' compensation, and potential conflicts between ADA obligations and terms of collective bargaining agreements. The EEOC has essentially left the resolution of many important ADA questions to case-by-case determination and the litigation process.  相似文献   
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"Selective pregnancy reduction" is a medical procedure used to reduce a multiple pregnancy, often a multiple pregnancy induced by in vitro fertilization or drug therapy. In such instances, healthy embryos are sacrificed in order to maximize the chances of survival of the remaining embryos or to allow the mother to choose the number of babies she wishes to deliver. Physicians appear to rely on Roe v. Wade in assuming the legality of the procedure, although such an assumption may be erroneous. Rather than continue to implant an excessive number of pre-embryos, the American Medical Association and the Association of Obstetrics and Gynecology should adopt guidelines similar to those established by the Voluntary Licensing Authority in London, which limit the number to be inserted to a maximum of three. Careful ultrasound monitoring could ensure that no more than three embryos implant when fertility drugs are used. Such practices would help physicians avoid the many moral, ethical, legal, and philosophical problems caused by selective pregnancy reduction.  相似文献   
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Although the formal institutional structure that defines the temporal order of play in a policy game between the Congress and President ought to provide Congress with agenda power, the President is traditionally treated as the dominant player in this relationship. We show that if the President can make clear-cut commitments, presidential commitment can counter the dominance hierarchy and the complexion of equilibrium outcomes. Thus, the details of political interactions (in particular, the possibilities for commitment) may be as important as the formal specification of institutional structure.We thank Peter Aranson, David Austen-Smith, Ed Campos, Gerry Faulhaber, Art Frank, Ken Koford, William Riker, Janet Pack, the anonymous referees, and seminar participants at the University of Delaware, the University of Pennsylvania, and the University of Rochester for helpful comments, subject to the usual caveat. We also thank Joel Friedlander and Harold Dichter for research assistance.  相似文献   
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