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181.
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Quality assurance samples submitted from the NCSBI as part of a contract with TBTG to outsource DNA Database samples showed unexpected discrepancies for the locus D16S539 when all other loci yielded identical results. Discrepancies observed included allele drop out and an imbalance in sister alleles with samples returned from TBTG. This led to a comprehensive review of the technical procedures used between the two laboratories to determine the cause of the discrepancies noted for the locus D16S539, since both laboratories were using the PowerPlex 1.1 typing kit from the Promega Corporation. The NCSBI and the TBTG utilize different extraction methods (organic extraction vs. FTA) and amplification conditions (AmpliTaq vs AmpliTaq Gold), respectively, so the exact cause of discrepancy observed was not immediately apparent. Experiments at the NCSBI associated the observed allele drop out and the imbalance of the sister alleles with the use of AmpliTaq Gold and a hot start procedure. Sequencing data revealed that a point mutation resides on the D16S539 primer-binding site that reaches polymorphic levels in African-American populations. This led to the development of a degenerate primer by the Promega Corporation to detect "missing" alleles when AmpliTaq Gold is used. The degenerate primer was then thoroughly tested to show its efficacy in detecting the "true" D16S539 profile when used.  相似文献   
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Oxycodone is a potent semi-synthetic narcotic prescribed for the management of pain. Previous investigators have reported that the abuse of oxycodone is most frequently seen in conjunction with the abuse of other drugs, although fatalities have been reported with oxycodone alone. We undertook a retrospective review of cases investigated by the Palm Beach County Medical Examiner's Office in which postmortem toxicologic studies indicated the presence of oxycodone. A total of 172 consecutive cases were studied, including 18 in which death was attributed to oxycodone toxicity, 117 to combined drug toxicity, 23 to trauma, 9 to natural causes and 5 to another drug or drugs. The postmortem blood concentrations of oxycodone overlapped among the groups. The mean blood oxycodone concentration among the cases of oxycodone toxicity was 0.69 mg/L, combined drug toxicity 0.72 mg/L and trauma 0.62 mg/L. Concentrations were lower in cases of deaths attributed to natural causes and to another drug or drugs (mean each 0.087 mg/L). Benzodiazepines, detected in 96 cases, were the most common co-intoxicants in the cases of combined drug toxicity, followed by cocaine, which was found in 41. The most frequently encountered benzodiazepine was alprazolam. This study confirms that deaths in which oxycodone is a factor are most commonly cases of combined drug toxicity. The high incidence of alprazolam as a co-intoxicant has not been previously recognized.  相似文献   
185.
In the "post-genomic" age of biomedical research, researchers often wish to utilise collections of human tissue. This type of research raises many ethical and legal issues and anyone wishing to use such collections is faced with an enormously complex set of regulatory requirements, many of which are still ambiguous, reflecting ongoing ethical and legal debate. Whilst there is no way of entirely avoiding such regulatory complexity and ambiguity, conceptual frameworks can assist those who wish to use, administer, authorise and generate policy on tissue banking research. Two conceptual frameworks are described here: a taxonomy of tissue banking practices, aimed at assisting those who need to ensure that tissue banks meet ethical and legal requirements; and a "syncretic" approach to policy-making, for those who wish to generate new policy, or streamline existing policy relating to tissue banking research.  相似文献   
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Recent research has highlighted the role of culture in emerging adulthood (age between 18 and 25 years). However, most studies have examined majority cultures (e.g., China) as well as subcultures (e.g., American ethnic minorities). Thus, work on other aspects of culture such as religion is needed given the emerging evidence that it may have an impact on development. This study explored the role of religious culture in the emerging adulthood of college students. Participants were 445 undergraduates (ages 18–20 years) from institutions that were Catholic (31 males, 89 females), Mormon (48 males, 200 females), and public (21 males, 56 females). Results found religious differences in (a) the criteria young people deemed necessary for adulthood, (b) the extent to which emerging adults felt they had achieved these criteria, (c) various aspects of spirituality including practices and beliefs, and (d) the behaviors in which emerging adults engage.Portions of this study were presented at the biennial meeting of the Society for Research in Adolescence, Baltimore, Maryland, in March 2004.Assistant Professor of Psychology at Loyola College in Maryland. She received her PhD in 2001 from the University of Maryland, College Park. Her major research interests are in social-and self-development during adolescence and emerging adulthood.Assistant Professor of Marriage, Family, and Human Development in the School of Family Life at Brigham Young University. He received his PhD in 2000 from the University of Maryland, College Park. His major research interests are in social-and self-development during early childhood and emerging adulthood.  相似文献   
188.
Derived from comparative approaches in both qualitative and quantitative research, the current study describes a simple exploratory technique for the multivariate analysis of categorical data. This technique is referred to as the conjunctive analysis of case configurations. After describing the logic and underlying assumptions of this conjunctive method, it is applied and illustrated in the study of the federal sentencing of drug offenders. The relative value of this conjunctive approach for purposes of exploratory data analysis and its overall utility as a method for confirmatory research are also discussed.
Terance D. MietheEmail:
  相似文献   
189.
A structural equation model based on social cognitive theory was used to predict relationship violence from young adolescents' knowledge, self-efficacy, attitudes, and alternative conflict strategies (n = 143 male and 147 female grade 7-9 students). A direct causal effect was supported for violence-tolerant attitudes and psychologically aggressive (escalation/blame) strategies on physical violence against dating partners and friends. Knowledge and self-efficacy contributed to using reasoning-based strategies, but this reduced violence only in boys' friendships. Knowledge reduced violence-tolerant attitudes, thus reducing escalation/ blame and physical violence. Attitudes toward male and female dating violence (ATMDV and ATFDV) were indicators of general attitudes toward violence among non-dating students but ATFDV affected physical violence and ATMDV affected psychological aggression for both dating boys and girls.  相似文献   
190.
Traditional theories of democracy suggest that political representation of excluded groups can reduce their incentives to engage in conflict and lead to lower violence. However, this argument ignores the response of established elites when (1) their interests are threatened by the policy stance of new political actors and (2) elites have a comparative advantage in the exercise of violence. Using a regression discontinuity approach, we show that the narrow election of previously excluded left‐wing parties to local executive office in Colombia results in a one standard deviation increase in violent events by right‐wing paramilitaries. We interpret this surge in violence as a reaction of traditional elites to offset the increase in outsiders' access to formal political power. Consistent with this interpretation, we find that violence by left‐wing guerrillas and other actors is unaffected and that violence is not influenced by the victory of right‐wing or other new parties in close elections.  相似文献   
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