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111.
Eighteen external quality assessment (proficiency testing) samples were prepared from client specimens collected with the Intercept® oral fluid collection device and by spiking drug-free oral fluid. Samples were circulated in pairs at quarterly intervals to 13 UK and USA based laboratories for analysis by a panel of OraSure micro-plate Intercept® enzyme immunoassay kits and hyphenated mass spectrophotometric techniques. During the survey, there was a single case of non-specificity in a false report for methadone. The major errors were of lack of sensitivity relative to the concentration thresholds specified for the immunoassays. The sensitivity for overall ‘present’/‘not found’ reports calculated as true positives/(true positives + false negatives) were for the amfetamine specific assay 50%, methyl-amfetamines 93%, barbiturates 64%, cannabinoids 73%, cocaine and metabolites 100%, benzodiazepines 69%, methadone 95%, opiates 79% (opiates excluding oxycodone 93%), phencyclidine 93% and human gamma-globulin 97%. A small number of the sensitivity errors were attributable to errors in chromatographic confirmation techniques.  相似文献   
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Pittenger  John C. 《Publius》1992,22(1):1-19
In Garcia v. San Antonio Metropolitan Transit Authority (1985),Justice Harry Blackmun held that the Tenth Amendment does notprevent the Congress from subjecting state and local governmentsto the provisions of the Fair Labor Standards Act, concludingthat the "political safeguards offederalism" are generally adequateto protect state interests on the national scene. This articleexamines the intellectual foundations of the "political safeguardsof federalism" and finds them inadequate. It then surveys thepost-Garcia scholarship to ascertain whether an alternativetheory of the Tenth Amendment has emerged. Concluding that ithas not, the author suggests the need for afresh approach inview of the hints contained in Justice Sandra Day O'Connor'sopinion in Gregory v. Ashcroft (1991) that five justices maybe ready to reexamine the central thesis of Garcia.  相似文献   
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The authors present a method to separate and preserve stomach contents for forensic purpose. Analysis by "sieve tower" technique is simple and quickly done during autopsy. Solid phases of stomach content are arranged size up and can be stored for subsequent examinations. With the fluid phase drug analysis or microscopic analysis to confirm identy of the foodstuffs may be done. By adding alcohol (70%) enzymatic digestion and bacterial degradation of the stomach content are stopped.  相似文献   
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In this article we examine how increasing the reimbursement of physicians and expanding Medicaid eligibility affect access to care for children in Cook County, Illinois, which overlies Chicago. Using Medicaid claims and other data at the zip-code level, we compare the places where Medicaid children live with the places where all the physicians who treat children and those who accept Medicaid patients have their practices. Our findings suggest that the recent changes in legislation are unlikely to benefit extremely poor children, who are more likely to live in depressed inner-city areas, where there are few physicians. "Near-poor" children whose homes are dispersed throughout the county, who are now eligible for Medicaid as a result of the recent changes, are likely to see improvements in their access to care. Further changes in policy, aimed at enhancing the capacity of institutions providing care, could improve access for the children of the inner city.  相似文献   
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