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451.
To date, the screening of meconium for the determination of tobacco exposure in newborns has proven difficult. It was hypothesized that cotinine forms reversible Schiff base bonds with free amino functions on proteins, therefore, hydrolysis of meconium would be necessary for the detection of 'free' cotinine. One-hundred-and-two (102) meconium samples received into our laboratory were extracted using a routine non-hydrolysis screening procedure for drugs of abuse. Separate aliquots of the specimens were hydrolyzed and re-extracted according to the same procedure. The results of the two methods were compared using a highly specific cotinine micro-plate enzyme immunoassay procedure (EIA). Of the non-hydrolyzed samples, 33% were positive for cotinine, while 79% of the hydrolyzed samples were cotinine-positive. Common drugs of abuse did not interfere with the analysis. Micro-plate EIA provides a rapid, simple and reliable screening method for the determination of cotinine in meconium following hydrolysis and extraction. In general, the meconium specimens received into our laboratory are from newborns considered to be at risk for post-natal problems due to suspected drug and/or alcohol abuse during pregnancy.  相似文献   
452.
A commercially available enzyme-linked immunosorbant assay (ELISA) was evaluated as a screening procedure for the detection of nine classes of abused drugs in postmortem blood and tissue specimens. Specifically, postmortem blood, fluid and/or tissue homogenates were screened for amphetamine (AMP), methamphetamine (MET), barbiturates (BARB), benzodiazepines (BZD), cannabinoids (CNB), cocaine (benzoylecgonine; BE), morphine-specific (MOR), opiates (class; OPI), phencyclidine (PCP) and lysergic acid diethylamide (LSD) by ELISA and by coated tube radioimmunoassay (CTR) (BARB, BE, OPI, PCP, LSD) or double-antibody radioimmunoassay (DAR) (AMP/METH, BZD, CNB). Specimens that screened 'positive' by any method were confirmed and quantitated by gas chromatography/mass spectrometry (GC/MS). The only assay that appeared to perform less optimally than RIA was the MOR assay (five false negatives). However, this assay is very specific for free morphine while the GC/MS confirmation method provided a total morphine value. The OPI assay was more sensitive, producing fewer false negatives, and is recommended for broad class opiate screening. EIA is an adequate alternative to RIA for screening postmortem specimens, including blood and tissue, for nine major classes of drugs.  相似文献   
453.
In January of 1999, leading negotiation scholars and practitioners gatheredat Northwestern University for a conference sponsored by the HewlettFoundation. Here, we chronicle a conversation that occurred regardingnegotiation research. Our diverse group consisted of people with backgroundsin social psychology, anthropology, sociology, and clinical practice.We discussed issues surrounding where research takes place (in the lab orin the field), experimental participants (students or practicing professionals),and the ultimate value of research.  相似文献   
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This article provides the first controlled evaluation of how different information materials explaining the risks from radon influenced people's perceptions of these risks. Using a panel study, it was possible to observe how stated risk perceptions responded to information about indoor radon concentrations and brochures explaining the radon readings. The findings indicate that risk communication policies can be effective in modifying risk perceptions. Moreover, they have three specific implications for radon policy: (1) Public officials should not adopt strategies that provide minimal risk information to the public as a means of avoiding undue alarm, for this can have the reverse effect; (2) measures of the effectiveness of risk communication will depend on how education and behavior change are defined; (3) categorical guidelines about risk without quantitative information can lead people to treat the levels as thresholds, creating an artificial discontinuity in their responses to small changes in risk perceptions.  相似文献   
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The emergence of a worldwide environmental movement in the early 1960s accompanied an international expansion of economic activity and applied technology. The principal medium through which this expansion progressed was trade. In 1947, following World War II, a series of international agreements were negotiated to regularize international relations in finance, monetary policies, and trade. The General Agreement on Tariffs and Trade (GATT) was negotiated without anticipation of an international environmental movement and new policies at the national level that did not reflect, and might be inconsistent with, economic values. Conflict between policies for freedom of trade and environmental protection did not immediately emerge. With the adoption of numerous environmental protection measures in the United States and many other countries after 1969, the incompatibility of some trade and environmental policies became political issues. Trade policies are not confined to economic changes. Policy issues developing around the agreement and environmental protection are complex, and frequently involve technological issues, as in the Mexican tuna controversy discussed in this paper.  相似文献   
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This note describes the Kaldor‐Hicks (KH) tableau format as a framework for distributional accounting in cost‐benefit analysis and policy evaluation. The KH tableau format can serve as a heuristic aid for teaching microeconomics‐based policy analysis, and offer insight to policy analysts and decisionmakers beyond conventional efficiency analysis. © 2005 by the Association for Public Policy Analysis and Management  相似文献   
460.
Aggregate pooled cross-sectional and time-series annual state data for 1985 to 1992 were used to estimate the systemwide effects of retrospective drug utilization review programs (Retro-DUR) on Medicaid drug and nondrug outcomes. The results provide evidence that these programs produce significant cost savings in the drug budget without spillover effects (positive or negative) in other nondrug budgets within the Medicaid system. We also examine the influence of restricted formularies in this post-Retro-DUR era on drug and nondrug budgets in the Medicaid system; we find significant cost savings in the former but positive spillover effects in the latter.  相似文献   
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