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81.
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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This Article examines the issues and questions which underlie the debate over the admission of "medical treatises" into evidence. The admissibility of this type of evidence is at issue most often in litigation involving complex medico-legal issues. This article outlines the evidentiary basis for admission of medical treatises and discusses the quality of medical treatises in an effort to determine what value to the fact-finder these treatises actually hold. The authors contend that there is an inherent untrustworthiness associated with medical treatises, but do not go so far as to suggest that medical treatises should never be admitted. The Article concludes that there is a need for greater caution in determining admissibility and recommends safeguards to better guarantee trustworthiness and reliability.  相似文献   
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In 1989, after almost two decades of substance-by-substance standard setting, the Occupational Safety and Health Administration (OSHA) promulgated its Air Contaminants Standard, imposing new exposure limits for 376 toxic substances encountered in U.S. industry. In marked contrast to earlier regulations, the Air Contaminants Standard has generated relatively little industry opposition. This paper analyzes the standard in the context of the twenty-year debate over the appropriate role for technological feasibility and economic compliance costs in occupational health policy. The political feasibility of the new standard is traced to OSHA's abandonment of "technology forcing" in favor of reliance on "off-the-shelf" technologies already in use in major firms. While important as an embodiment of OSHA's new "generic" approach to regulation, the Air Contaminants Standard cannot serve as a model for future occupational health policy, due to its reliance on informal, closed-door mechanisms for establishing regulatory priorities and permissible exposure limits.  相似文献   
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Ames K  Wilson L  Sawhill R  Glick D  King P 《Newsweek》1991,118(9):40-41
When dying is all that awaits them, more and more people are choosing certain death now rather than uncertain life on medical support systems. But the decision seldom comes easy, as a Newsweek reporter discovers during three weeks with the doctors, nurses, patients and families in an intensive-care ward. A best-selling guide to suicide fires debate over when it is right to let life go--and who should make that choice when the patient no longer can.  相似文献   
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