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141.
体液中氟乙酰胺SPE-GC/MS检测 总被引:1,自引:1,他引:0
目的 利用GC/MS与固相萃取 (SPE)技术相结合 ,开发血和尿样中氟乙酰胺鼠药的GC/MS定量分析新方法 ,并用于实际案例检测。方法 选择乙酰胺为内标 ,通过比较不同固相柱的萃取效率和不同条件对回收率的影响 ,优化用于血和尿样中氟乙酰胺萃取的固相柱和提取条件 ,利用氟乙酰胺与乙酰胺质谱图的分子离子峰面积之比与氟乙酰胺浓度的定量关系 ,建立血和尿样中氟乙酰胺鼠药的GC/MS定量分析新方法。结果 用硅胶柱萃取 ,峰面积之比与氟乙酰胺浓度在 5 0~ 90 μg/ml范围呈线性关系 ,检测限为 1 0 μg/ml。血样中氟乙酰胺检测的平均回收率达 91 6% ,标准偏差小于 7 3 %。结论 此法对实际样品的测定证明可满足氟乙酰胺鼠药中毒的定性定量要求。 相似文献
142.
目的建立苯二氮卓类药物氯氮平的串联质谱检验方法,以排除干扰物质,提高灵敏度。方法用串联质谱方法分析。结果以基峰m/z243为母离子,碰撞诱导电压(CID)为0.8v,进行MS/MS分析。结论与GC/MS相比,GC/MS/MS方法选择性好、灵敏度最高,排除干扰性能强。 相似文献
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This paper reports the results of four studies that investigate racial profiling as an attribution about police motives. Each study explores, first, the types of police behavior that heighten or lessen the occurrence of profiling attributions and, second, the consequences of such attributions. Results support prior studies in finding that judgments about whether the police are profiling are associated with the level of public support for the police. The studies then extend the analysis of subjective profiling judgments by examining their antecedents. The findings support the procedural justice hypothesis that the fairness with which the police exercise their authority influences whether members of the public view the police as profiling. 相似文献
145.
This paper examines the relationship between a mother's age at first childbirth and the delinquent behavior of her children. Using data from the Rochester Youth Development Study (RYDS), an ongoing longitudinal study of adolescent development, we found that children born to mothers who began childbearing at a young age were more prone to general delinquency, violence, and arrest than were children born to mothers who began childbearing when they were older. This “early first‐birth effect” was far larger in white and Hispanic families than in African‐American families. Mediating analyses found that the early first‐birth effect was most attributable to the unstable composition of families in which early childbearing occurs. That said, a substantial portion of the effect remains unmediated. 相似文献
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Extending Koons‐Witt's (2002) study of whether sex‐based disparities in imprisonment likelihoods changed under sentencing guidelines in Minnesota, we examined similar models for Ohio with additional analyses of felony conviction likelihoods and sentence length for 5,472 felony defendants from twenty‐four trial courts. The main effects of a defendant's sex on imprisonment were significant during both periods (unlike the Minnesota findings), consistent with a chivalry perspective. Random coefficient models revealed that these effects were similar across the twenty‐four jurisdictions. Analyses also revealed significant postguideline reductions in sentence length disparities based on a woman's race and number of dependent children, yet increased disparities in imprisonment likelihoods postguidelines based on a woman's race and whether she was convicted on drug charges. These and other findings are discussed in the context of the Ohio legislature's implementation of a sentencing scheme that retains considerably more judicial discretion relative to Minnesota's template. 相似文献
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Sharon N. Clarke 《Family Court Review》2006,44(1):149-163
Studies estimate that between three and ten million children in the United States witness domestic violence annually. Although studies have demonstrated a co‐occurrence of domestic violence and child abuse, there is no concrete evidence to support the assumption that a child's exposure to domestic violence increases the risk to the child of abuse or neglect. Recently the New York State Court of Appeals determined that a child's witness to abuse does not suffice, in and of itself, to show that removal of the child is necessary or that removal is in the “best interests” of the child. Programs which have developed alternatives to presumptive removal understand the importance of viewing the interests of the battered parent and children as being in accord with each other rather than in opposition. Private and government sponsored programs have demonstrated some success in protecting the parent‐child relationship, ensuring the safety of both parent and child, and increasing accountability of batterers while reducing the necessity for removals. Alternative programs are less costly to the state than foster care, and emotionally less costly to the families. 相似文献
150.
Tarek Belal Tamer Awad Jack DeRuiter C. Randall Clark 《Forensic Science International Supplement Series》2008,178(1):61-82
A series of side chain regioisomers of 3-methoxy-4-methyl- and 4-methoxy-4-methyl-phenethylamines have mass spectra essentially equivalent to the controlled drug substance 3,4-methylenedioxymethamphetamine (3,4-MDMA), all have molecular weight of 193 and major fragment ions in their electron ionization mass spectra at m/z 58 and 135/136. The acetyl, propionyl and trifluoroacetyl derivatives of the primary and secondary regioisomeric amines were prepared and evaluated in GC–MS studies. The mass spectra for these derivatives were significantly individualized and the resulting unique fragment ions allowed for specific side chain identification. The trifluoroacetyl derivatives provided more fragment ions for molecular individualization among these regioisomeric substances. These trifluoroacetyl derivatives showed excellent resolution on a non-polar stationary phase such as Rtx-1. 相似文献