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11.
顶空固相微萃取气相色谱法快速检测尿液中氯胺酮 总被引:1,自引:1,他引:0
目的建立快速检测吸毒人员尿液中氯胺酮的顶空固相微萃取(HS/SPME)-GC/NPD的方法。方法样品瓶中加入尿液、氢氧化钠溶液、氯化钠,在95℃下加热搅拌,用聚二甲基硅氧烷SPME萃取头(100μm)顶空萃取20min,气相色谱氮磷检测器检测,外标法定量。结果尿液中氯胺酮浓度在0.2~20.0μg/ml范围内呈现线性关系(r2=0.9965),尿液添加1.0μg氯胺酮,平均回收率102.6%,RSD=3.39%(n=7),检测限1.13ng/ml(S/N=3)。结论建立的方法简单、快速、灵敏、准确,十分适合尿液等生物检材中氯胺酮的快速定性定量分析。 相似文献
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Prior studies of recidivism have focused almost exclusively on individual‐level characteristics of offenders and their offenses to explore the correlates of reoffending. Notably absent from these studies are measures reflecting the neighborhood contexts in which individuals live. The current research addresses this shortcoming. Using data on a sample of ex‐offenders in Multnomah County, Oregon (Portland and surrounding area) in conjunction with 2000 census data, we answer two questions. First, which individual‐level factors influence rates of recidivism? Second, to what extent does neighborhood socioeconomic status account for variation in the reoffending behavior of ex‐prisoners that is not explained by their individual‐level characteristics? We find that those who return to disadvantaged neighborhoods recidivate at a greater rate while those who return to resource rich or affluent communities recidivate at a lesser rate, controlling for individual‐level factors. 相似文献
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A growing body of evidence shows that minorities are disproportionately the targets of police brutality, but important theoretical questions about the causes of that inequity remain unanswered. One promising line of research involves structural‐level analyses of the incidence of police brutality complaints; however, existing studies do not incorporate variables from alternative theoretical explanations. Drawing on the community accountability hypothesis and the threat hypothesis, we tested the predictions of two prominent structural‐level explanations of police brutality in a study of civil rights criminal complaints. The study included cities of 150,000+ population (n = 114). The findings reveal that two community accountability variables—ratio percent Hispanic citizens to percent Hispanic police officers and the presence of citizen review—were related positively to police brutality complaints, partially supporting that perspective. Two threat hypothesis measures of threatening people—percent black and percent Hispanic (in the Southwest)—were related positively to complaints, as predicted. The relative degree of support for the two hypotheses is assessed. 相似文献
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Joanna Bunker Rohrbaugh 《Family Court Review》2006,44(2):287-299
Physical violence occurs in 11–12% of same‐gender couples, which suggests that domestic violence is an abuse of power that can happen in any type of intimate relationship, regardless of gender or sexual orientation. Although incidents of violence occur at the same rate in same‐gender couples and cross‐gender couples, the violence appears to be milder in same‐gender couples and it is unclear what percentage of same‐gender violence should be characterized as abuse or intimate terrorism. Same‐gender victims also suffer from the additional stress of severe isolation and the abuser's threats to expose the victim's sexual orientation in a hostile manner. 相似文献
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Helena Teixeira Paula Proena Alain Verstraete Francisco Corte-Real Duarte Nuno Vieira 《Forensic Science International Supplement Series》2005,150(2-3):205
An analytical method using solid-phase extraction (SPE) and high-performance liquid chromatography–mass spectrometry (LC–MS) has been developed and validated for the confirmation of Δ9-tetrahydrocannabinol (THC) in oral fluid samples. Oral fluid was extracted using Bond Elut LRC-Certify solid-phase extraction columns (10 cm3, 300 mg) and elution performed with n-hexane/ethyl acetate. Quantitation made use of the selected ion-recording mode (SIR) using the most abundant characteristic ion [THC + H+], m/z 315.31 and the fragment ion, m/z 193.13 for confirmation, and m/z 318.00 for the protonated internal standard, [d3-THC + H+]. The method proved to be precise for THC, in terms of both intra-day and inter-day analyses, with coefficients of variation less than 10%, and the calculated extraction efficiencies for THC ranged from 76 to 83%. Calibration standards spiked with THC between 2 and 100 ng/mL showed a linear relationship (r2 = 0.999). The method presented was applied to the oral fluid samples taken from the volunteers during the largest music event in Portugal, named Rock in Rio-Lisboa. Oral fluid was collected from 40 persons by expectoration and with Salivette®. In 55% of the samples obtained by expectorating, THC was detected with concentration ranges from 1033 to 6552 ng/mL and in 45% of cases THC was detected at concentrations between 51 and 937 ng/mL. However, using Salivette® collection, 26 of the 40 cases had an undetectable THC. 相似文献
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