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d-3-Methoxy-17-methylmorphinan (Dextromethorphan, DXM), which is a structural analog of morphine and codeine, has been widely used as a non-narcotic antitussive agent. It is a safe drug in therapeutic dose and does not produce analgesic effects, while its enantiomer, l-3-methoxy-17-methylmorphinan called levomethorphan (LXM) is a potent narcotic analgesic. DXM has been widely abused in Korea due to its hallucinogenic effect in large doses; therefore, the health authorities have regulated its use as a psychotropic agent since 2003. As its abuse has been serious, a possibility that DXM would be smuggled into Korea has also increased. Moreover, it has been suspected that there was the possibility of the adulteration or substitution of DXM with LXM due to their chemical similarities. Therefore, it was necessary for us to establish the enantiomeric separation of DXM and LXM. In this study, a liquid chromatographic method using a chiral column capable of separating stereoisomers of DXM as well as analyzing the major metabolites of DXM, 3-methoxymorphinan, 3-hydroxymorphinan, and 17-hydroxymethylmorphinan was developed. The validation of a method was studied through repeatability of retention times. Using this method, 32 confiscated DXM samples were analyzed to identify the enantiomers of DXM. As a result, DXM was detected in all samples and there was no evidence of the adulteration or substitution of DXM with LXM. Nevertheless, the stereochemical analysis of DXM and LXM is important not only to identify starting materials for illegal drug manufacture but also to understand the trends of abused drugs. 相似文献
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Garg U Althahabi R Amirahmadi V Brod M Blanchard C Young T 《Journal of forensic sciences》2004,49(2):388-391
Vitreous humor is a suitable specimen for postmortem clinical chemistry because the analytes remain relatively stable after death and they closely reflect blood levels immediately prior to death. The viscous nature of vitreous fluid, however, presents analytical problems including imprecision and inaccuracy. Various preanalytical treatments, such as boiling, high speed centrifugation, microfiltration and dilution have been used. These techniques are labor intensive and add to imprecision and inaccuracy. Because glycosaminoglycans contribute significantly to the viscosity of vitreous humor, we used hyaluronidase as a liquefying agent. We compared the results of analyses in 33 vitreous humor specimens after hyaluronidase treatment with the results after either no treatment or specimen dilution. Seventeen of the 33 specimens could not be analyzed without dilution. Even after dilution, several analytes still could not be measured. Hyaluronidase treatment negated the need for sample dilution and had no significant effect on the analyses. 相似文献
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Economists and political scientists have offered a variety of explanations for why legislators might rationally choose to ignore the preferences of their constituents, political parties, and presidents. The broad conclusion of this literature is that there is an element of “shirking” in congressional voting. The objective of this paper is to suggest that the effects of shirking in congressional voting may have increased over time, largely in response to the raising of barriers to competition in congressional elections, thereby enabling legislators to vote their own preferences without fear of losing reelection. We use a quasi-experimental design that controls for the effects of party, region, electoral safety, presidential control of the White House, and constituency factors, in isolating the causal effects of barriers to entry on a continuous series of roll-calls regarding the raising of the debt limit between 1953 and 1992. We find that “shirking” in legislative voting on debt limit legislation is a post-1970s phenomenon. 相似文献
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In this essay we examine some issues of justice associated with the siting of hazardous industrial facilities. Utilitarian justifications of siting decisions are inadequate because they fail to address questions of fairness. Approaches that consider questions of distributive equity provide a better framework for siting justice, but are still incomplete. Limiting questions of justice to the distribution of benefits and burdens fails to examine the justice of procedures for deciding such issues of distribution. We argue that justice requires a participatory communicative democratic process for siting hazardous facilities, in two respects. It is prima facie unjust to impose a risk on citizens without their having participated in the siting process. Participatory communicative democratic procedures in facility siting, moreover, when structured according to specific norms of discussion and inclusion, are likely to yield the most just outcomes. We propose procedural as well as substantive conditions for such democratic procedures, and briefly apply these conditions to evaluate the siting of a landfill in Switzerland. 相似文献
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