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41.
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 methodological paper presents the utility of survival analysis methods to provide age adjustment in the analysis of domestic violence data. These methods improve the estimation of lifetime probability of domestic violence, improve identification of patterns of first victimization over the lifespan, and provide methods of testing risk factors for first victimization while adjusting for the respondents' age. Most importantly, these methods allow a new investigation of recall bias. Results suggest that lifetime probability of abuse may have been substantially underestimated in previous studies because of problems in recall/disclosure encountered by middle-aged women.  相似文献   
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Incarceration rates in the United States dramatically increased over the past several decades. This trend has drawn significant academic attention to prison overcrowding and its potential effect on inmate misconduct. The empirical relationship between inmate misconduct and overcrowding, however, is less than clear. To be sure, studies indicating positive, negative, and null relationships can all be found in the literature. The current research subjects this body of literature to a meta-analysis in an effort to: (1) clarify the direction and strength of the relationship between overcrowding and rates of prison misconduct across all studies, and (2) to uncover the degree to which variation in research outcomes can be attributed to methodological differences across studies. Results indicate that prison crowding has little substantive impact on inmate misconduct. Implications of the findings are discussed in detail.  相似文献   
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The social development model (SDM) is a theory of behavior that has proven useful in explaining the etiology of delinquency, violence, and substance use among adolescents as well as early antisocial behavior among pre-adolescents. A further test of the model is its generalizability across population groups. A section of the SDM representing prosocial influences in the etiology of problem behavior was compared for boys and girls and for children from low- and non low-income families using three waves of child, parent and teacher survey data on a sample of 851 elementary school students. Multiple group structural equation modeling was used to assess differences across groups in both measurement of model constructs and hypothesized structural paths between constructs. The results indicate overall similarity in the reliability of measurement models and validity of structural models.  相似文献   
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Rethinking the Meaning of Public Health   总被引:1,自引:0,他引:1  
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