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241.
Allison M. Curran Ph.D. ; Paola A. Prada B.S. ; Kenneth G. Furton Ph.D. 《Journal of forensic sciences》2010,55(1):50-57
Abstract: Human scent evidence is utilized as an investigative tool through canine scent discriminations based on the premise that human scent is an individualizing characteristic. This study describes the development of what is effectively a human scent barcode consisting of the relative ratios of an individual's "primary odor" compounds utilized to determine a reproducible and individualizing profile which can be stored in a searchable database for a proof of concept of human scent as a biometric measure. Triplicate hand odor samples were evaluated from 10 subjects utilizing solid phase micro-extraction gas chromatography/mass spectrometry (SPME-GC/MS) and compared via Spearman Rank Correlations. Narrowing the compounds considered for each subject to only those common in all three samples, or a subject's "primary odor constituents," produced a greater degree of both individualization and discrimination; at both correlation thresholds of 0.9 and 0.8, the individuals were correctly discriminated and identified in 99.54% of the cases. 相似文献
242.
Anders Buchard M.Sc. Kristian Linnet M.D. D.M.Sc. Sys Stybe Johansen Ph.D. Julie Munkholm M.D. Michael Fregerslev M.D. Niels Morling M.D. D.M.Sc. 《Journal of forensic sciences》2010,55(2):457-463
Abstract: We investigated toxicological and pharmacogenetic factors that could influence methadone toxicity using postmortem samples. R‐ and S‐methadone were measured in femoral blood from 90 postmortem cases, mainly drug users. The R‐enantiomer concentrations significantly exceeded that of the S‐enantiomers (Wilcoxon’s test, p < 0.001). The samples were divided into four groups according to other drugs detected (methadone only, methadone and strong analgesics, methadone and benzodiazepines, or methadone and other drugs). There was no significant difference in any of the R‐methadone/total methadone ratios among the four groups. The median R/S ratio was 1.38, which tends to be higher than that reported for the plasma of living subjects. In addition, we investigated whether small nucleotide polymorphisms in the MDR1 gene that encode the drug transporter P‐glycoprotein were associated with the concentrations of R‐ and S‐methadone and its metabolite 2‐ethylidene‐1,5‐dimethyl‐3,3‐diphenylpyrrolidine. No significant association was detected. 相似文献
243.
目的建立血、肝组织中芬太尼和舒芬太尼的HPLC-MS/MS分析方法。方法采用Oasis(MCX固相萃取柱进行提取,以XTerraTMRP18柱(2.1mm×100mm,3.5μm)色谱柱分离,以乙腈∶5mmol/L醋酸铵水溶液(氨水调pH=9.5)(65∶35)为流动相,流速为0.2mL/min。结果血及肝组织添加样品的线性范围为10ng/mL~500ng/mL,最小检出限为0.1ng/mL。结论本方法准确、快速,可用于生物检材血、肝组织中芬太尼和舒芬太尼的定性定量分析。 相似文献
244.
目的利用GC/MS、GC/NPD与固相萃取(SPE)技术相结合,建立血液中苯丙胺类毒品的定性定量分析方法。方法采用Bond—ElutCerti{y固相柱、甲醇淋洗、二氯甲烷/异丙醇/氨水(78/20/2)洗脱固相萃取分离提取,比较了不同PH体系、稀释状态、洗脱溶剂对提取回收率的影响,建立血液中苯丙胺类毒品的GC/MS、GC/NPD定性定量分析方法。结果以GC/NPD分析AM、MA、MDA和MDMA浓度在15ng/mL-2000ng/mL、10ng/mL~1600ng/mL、20ng/mL-3000ng/ml、20ng/mL-3000ng/mL范围内线性关系良好,AM、MA、MDA和MDMA的检测限分别为10ng/mL、8ng/mL、15ng/mL、15ng/mL,方法平均回收率大于85%,标准偏差小于5%,GC/MS-Scan检测限分别为40ng/mL、32.0ng/mL、60.0ng/mL、60.0ng/mL。结论此方法可满足苯丙胺类毒品滥用者的血液定性定量分析。 相似文献
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246.
孟金梅 《北京政法职业学院学报》2010,(4):84-90
第十八届国际艾滋病会议于2010年7月在维也纳召开。会议主要讨论了同性恋、性工作和吸毒非罪化问题及关于艾滋病强制检测、艾滋病隐私和艾滋病传播犯罪问题。此外,有可能开发成功降低艾滋病感染风险的药物和有效预防艾滋病的疫苗。中国代表团参加会议并介绍了我国艾滋病防治的情况。 相似文献
247.
Mikel Buesa Joost Heijs Thomas Baumert Javier González Gómez 《Terrorism and Political Violence》2013,25(4):489-509
This article attempts to measure the direct costs that the terrorist attacks of 3/11 had on the economy of the region of Madrid. The evaluation has been made applying conservative criteria, and the results obtained have to be considered as minimum. The result indicates that the terrorist attacks caused a loss of nearly 212 million euros to the regional economy of Madrid, equivalent to 0.16 percent of the regional GDP (0.03 of the national GDP). This confirms that the immediate economic dimension of a terrorist attack such as the one of 3/11—apart from human catastrophic consequences—is relatively low. 相似文献
248.
249.
为探究中华鳖天然免疫的分子机制,针对TLR2(Toll-like receptor 2)保守区设计兼并引物,从中华鳖脾cDNA中扩增出了740bp的目标序列。测序和序列分析结果表明,该序列包含富含半胱氨酸型C端结构域、跨膜结构域和TIR结构域;与斑马鱼、鸡等脊椎动物相应的TLR2序列相似性为60.5%~74.4%。采用荧光定量PCR检测中华鳖感染嗜水气单胞菌后各组织TLR2mRNA表达的变化,结果显示,感染后第24小时,中华鳖脾和外周血TLR2mRNA相对表达水平升高,其中外周血中的增幅最显著,是对照组的8.57倍;中华鳖外周血经4μg/mL酵母聚糖刺激后,第2小时TLR2mRNA相对表达水平较高。首次获得了中华鳖TLR2部分cDNA序列,并分析了不同刺激物对中华鳖TLR2mRNA转录的影响。 相似文献
250.
《国际相互影响》2012,38(3):352-364
Recent studies examining the political impact of individuals' connections to the victims of international violence find these ties have a powerful effect on people's attitudes and feelings. How reliable, however, are self-reported claims of ties to a conflict's casualties? Using data from 9/11 and the Iraq War, I examine these claims, analyzing: 1) their influence on both public assessments of foreign policy and voting behavior, 2) whether critical demographic and political factors predict the likelihood of individuals reporting a tie to a conflict casualty, 3) the predicted, aggregate likelihood of survey respondents having connections to conflict victims, and 4) the theoretical distinction between actual vs. perceived casualty connections. The results strongly support the use of casualty connection data for understanding individuals' responses to international violence, and encourage future applications of social network approaches to the study of war and politics. 相似文献