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871.
卜俊  刘伟  严慧 《法医学杂志》2009,25(5):359-361
目的探讨不同保存温度下血样中毒鼠强的稳定性。方法配制毒鼠强质量浓度为0.5μg/mL的血液样品,分别置于45℃、25℃和4℃环境中保存,在配制当天及存放3、12、18和39d用气相色谱-质谱联用法测定其质量浓度,运用SPSS统计软件对结果进行统计分析。结果45℃、25℃下血样存放3d毒鼠强质量浓度基本不变,存放4~12d毒鼠强质量浓度有明显下降,存放12d后毒鼠强质量浓度缓慢下降;4℃下血样存放12d毒鼠强质量浓度基本不变,存放13~18d毒鼠强质量浓度有明显下降,存放18d后毒鼠强样品质量浓度缓慢下降。结论血样中毒鼠强质量浓度在最初的3d内稳定,此后浓度下降。保存温度对血样中毒鼠强质量浓度有影响。  相似文献   
872.
王娟 《政法学刊》2009,26(5):104-107
公众安全感是指居民对社会治安状况的主观感受和评价,它反映了公众对犯罪的恐惧程度,也成为衡量和谐社会建设的一个重要指标。建立了我国公众安全感的评价指标体系,包括四个层次和四个系统。并为该指标的理论分析提出了主成分分析和聚类分析相结合的评价方法。  相似文献   
873.
The isotope ratios of amphetamine type stimulants (ATS) depend as well on the precursor as the synthetic pathway. For clandestine production of amphetamine and methamphetamine, 1-phenyl-2-propanone (P2P, benzylmethylketone) is a commonly used precursor.Our aim was to determine the variation of the isotope ratios within precursor samples of one manufacturer and to compare seized samples of unknown sources to these values. δ13CV-PDB, δ2HV-SMOW and δ18OV-SMOW isotope ratios were determined using elemental analysis (EA) and gas chromatography (GC) coupled to an isotope ratio mass spectrometer (IRMS). The comparison of all seized samples to the data of the samples of one manufacturer revealed considerable differences. The results show that IRMS provides a high potential in differentiating between precursors from different manufacturers for the clandestine production of ATS and identifying corresponding sources.  相似文献   
874.
875.
将国家机关、国有事业单位作为单位犯罪的主体会导致大大降低相关犯罪的刑罚成本,并不利于对此类犯罪的预防。根据以经济分析法学方法进行的分析,国家机关、国有事业单位均不宜成为单位犯罪的主体。  相似文献   
876.
Postmortem redistribution (PMR) constitutes a multifaceted process, which renders the analytical results of drug concentrations inaccurate to be interpreted by forensic toxicologists. The aim of the present study was to evaluate whether quantitative structure–activity relationship (QSAR) methodology could serve as an effective tool to estimate the ability of drugs to redistribute across tissue barriers during postmortem period on the basis of their molecular, physicochemical and structural properties. In this aspect, multivariate data analysis (MVDA) was applied to a set of 77 structurally diverse drugs. PMR data expressed by the central:peripheral concentration ratio (C:P ratio) was taken from the literature. An adequate and robust QSAR model (R2 = 0.65, Q2 = 0.56, RMSEE = 0.34) was established for 59 (77%) out of 77 drugs. Although the derived QSAR model presented limited applicability, it provided an informative illustration of the contributing molecular, physicochemical and structural properties in PMR process. Drugs with strong basic properties and enhanced molecular size, flexibility, lipophilicity and number of halogens were found to be susceptible to increased PMR. Due to the high complexity of PMR process, further QSAR studies need to focus on structurally related drugs to develop more specific models, which could serve as alternative tools to evaluate PMR for different chemical classes.  相似文献   
877.
878.
Calcified tissues, such as bone and tooth, and some other sample types, such as those containing adhesive, present a challenge to standard extraction protocols. We have developed a lysis reagent, BTA™ lysis buffer, which is designed for use with PrepFiler™ Kit reagents. The BTA™ lysis buffer disrupts calcified tissue matrices and achieves effective extraction of DNA from pulverized bone and tooth samples. In addition, the BTA™ lysis buffer mildly but efficiently extracts DNA from challenging substrates like tape, chewing gum, and cigarette butts and, as with bone and tooth, DNA from these lysates is purified using established PrepFiler™ reagent extraction protocols.We successfully extracted DNA from powdered human bone samples, chewed gum and smoked cigarettes using BTA™ lysis buffer. Extraction yields for bone, gum and cigarette samples tested were consistent and reproducible. This extraction method efficiently removed potential PCR inhibitors from all samples tested, and CT values for the internal PCR control of Quantifiler® Human DNA Quantification Kit were consistent and within the normal range. The DNA extracted from these samples also provided conclusive profiles that were free of PCR artifacts when amplified using the AmpF?STR® Identifiler® PCR Amplification Kit. The protocol is easily adapted for automation.  相似文献   
879.
880.
行为人在实施侵犯人身暴力犯罪后“捎带财物行为”的定性,应当具体分析暴力犯罪后“捎带财物行为”性质,即判断先前侵犯人身的暴力犯罪给被害人造成的状态,接着判断先前暴力行为是否形成新的“威胁”以及是否被“捎带财物行为”实施时所利用,最终作出合理的结论。  相似文献   
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