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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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This paper examines the inner workings of Chinese human smuggling organizations. Contrary to widely held conceptions about Chinese organized crime, most alien smugglers are otherwise ordinary citizens whose familial networks and fortuitous social contacts have enabled them to pool resources to transport human cargoes around the world. They come from diverse backgrounds and form temporary alliances to carry out smuggling operations. With the exception of a shared commitment to making money, little holds them together. The smuggling organizations mostly resemble ad hoc task forces and are assembled for specific operations. These organizations have clear divisions of labor with limited hierarchical structures. We discuss the theoretical implications of their unique organizational characteristics.  相似文献   
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This study uses a structured vignette procedure to assess competency to make treatment decisions in two groups of adolescents, one at risk for institutional placement and the other a matched community sample. Scores on Factual Understanding (the ability to recall facts), Inferential Understanding (the ability to make inferences about those facts), and Reasoning (the ability to weigh risks and benefits of various treatment options and to make choices based on that reasoning) were compared. Results showed that while at-risk adolescents and their community, counterparts did not differ in their factual and inferential understanding abilities, the at-risk adolescents did significantly less well than the community adolescents in reasoning. This difference could not be fully explained by differences in verbal IQ. Girls, no matter what their risk status, scored higher than boys on the Reasoning scale. Implications for legal policies concerning adolescents are discussed.  相似文献   
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