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C Moore S Browne I Tebbett A Negrusz W Meyer L Jain 《Forensic science international》1992,56(2):177-181
A new solid-phase extraction procedure for the determination of cocaine and benzoylecgonine in amniotic fluid, using high flow co-polymeric sorbents is reported. The recoveries of cocaine and benzoylecgonine within the range 0.1-1 mg/l were 95.7% and 50.3%, respectively. The use of high-flow sorbents allowed the easy extraction of amniotic fluid regardless of sample viscosity or physical nature. The use of these solid-phase columns provided many advantages over the more commonly used solvent extraction, including an increase in extraction speed and efficiency, reduced operator time, reduced solvent use and disposal volumes and exceptional extract quality. Further, the determination of amniotic fluid obtained from pregnant cocaine users may provide important information about handling of cocaine by the fetus at various gestational ages. The procedure was successfully applied to amniotic fluid from suspected cocaine abusers. 相似文献
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An improved method has been developed for the reliable classification of different C1R genetic variant forms from human serum or plasma. The method combines the use of neuraminidase-digested samples followed by monodimensional isoelectric focusing in the pH range 5 to 8 followed by immunoblotting. The method yields a simple pattern, with one major band in homozygote and two major bands in heterozygote cases. 相似文献
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Bruce Pilbeam 《Political studies》2003,51(3):490-508
This article examines the relationship between conservatism and environmentalism, including the viability of an eco-conservative ideology. The discussion emphasizes two major points. First, that there is much greater shared ground between greens and conservatives than is often recognized. Yet second, that there are nonetheless significant obstacles to any harmonious alliance between the two. However, what is also shown is that these obstacles are not necessarily those most commonly cited. 相似文献
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Federal transportation officials assert that labor protections in the Urban Mass Transportation Act inhibit the propensity of local transit agencies to contract with private firms for services. The authors present results from a survey of a large sample of transit managers and econometric analysis to support their conclusion that labor protections do not appear to reduce the incidence of contracting. The labor protections, however, may be costly to transit management in other ways. The authors recommend actions, aside from repeal of labor protections, to increase contracting by local transit agencies. 相似文献
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Bruce A. Kimball 《Law & social inquiry》2006,31(3):617-648
Compared to the practice in other professional schools and academic fields at universities, law professors are hired at a young age based primarily upon their academic merit determined through grades, class rank, and school rank. This emphasis upon narrowly defined academic merit—apart from achievement demonstrated through original scholarship or experience in professional practice—first emerged during "the professionalization of the American law professor" between 1870 and 1900 at Harvard Law School (HLS). Though normative today, this outcome was neither necessary nor uncontested. In the late nineteenth century the new standard of hiring faculty according to their academic merit was energetically opposed by those favoring the antecedent standard of professional experience and reputation. Only when financial considerations counterbalanced that traditional standard did hiring decisions tip in favor of the new principle. Not until the early 1900s, when the second generation of academic meritocrats dominated the HLS faculty, did the new hiring standard become unequivocally established as policy in the school and, by extension, in legal education. 相似文献
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Some features of early child care are more prominent in Norway than in other countries, such as emphasis on the outdoor environment. Of general relevance and interest is the form of day care provided by forest day-care centers. Three ideas form the development of these centers placed in wild areas. First, throughout history, Norwegians have had a close attachment to nature and some parents want to provide their children with outdoor experiences at an early age. Second, urging children to play outdoors characterizes the image many parents have of a happy, healthy childhood. Third, provision of day care for children has always been restricted in western countries, forcing parents to invent types of service that can become part of an ecological system that promotes healthy development.The forest day-care centers developed recently represent a supplement to the wide typology of child care in the 21st century. The article outlines the connections between these ideas in general European and western history and Norwegian history and presents debate and decisions about a question dating from the last half of the 1980s. It concludes that the forest day-care centers are perhaps only a modern form of the original kindergarten concept, which started in Europe and America as gardens for children not gardens of children. 相似文献
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