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排序方式: 共有1285条查询结果,搜索用时 15 毫秒
901.
Successful DNA-based identification of mass disaster victims depends on acquiring tissues that are not highly degraded. In this study, multiple protocols for field preservation of tissues for later DNA analysis were tested. Skin and muscle samples were collected from decaying pig carcasses. Tissues were preserved using cold storage, desiccation, or room temperature storage in preservative solutions for up to 6 months. DNA quality was assessed through amplification of successively larger segments of nuclear DNA. Solution-based storage, including a DMSO/NaCl/EDTA mixture, alcohols, and RNAlater preserved DNA of the highest quality, refrigeration was intermediate, and desiccation was least effective. Tissue type and extent of decomposition significantly affected stored DNA quality. Overall, the results indicate that any tissue preservation attempt is far superior to delaying or forgoing preservation efforts, and that simple, inexpensive methods can be highly effective in preserving DNA, thus should be initiated as quickly as possible. 相似文献
902.
903.
Sarah Kerrigan Ph.D. Ashley Mott M.S. Breanna Jatzlau M.S. Francisco Ortiz M.S. Laura Perrella M.S. Sarah Martin M.S. Kelsie Bryand M.S. 《Journal of forensic sciences》2014,59(1):175-183
Designer psychostimulants are known by recreational drug users to produce a complex array of adrenergic and hallucinogenic effects. Many of these drugs are not targeted during routine toxicology testing and as a consequence, they are rarely reported. The purpose of this study was to develop a procedure for the detection of 15 psychostimulants in urine using liquid chromatography–tandem mass spectrometry (LC‐MS/MS), specifically 2,5‐dimethoxy‐4‐bromophenethylamine (2C‐B), 2,5‐dimethoxy‐4‐chlorophenethylamine (2C‐C), 2,5‐dimethoxy‐4‐methylphenethylamine (2C‐D), 2,5‐dimethoxy‐4‐ethylphenethylamine (2C‐E), 2,5‐dimethoxyphenethylamine (2C‐H), 2,5‐dimethoxy‐4‐iodophenethylamine (2C‐I), 2,5‐dimethoxy‐4‐ethylthiophenethylamine (2C‐T‐2), 2,5‐dimethoxy‐4‐isopropylthiophenethylamine (2C‐T‐4), 2,5‐dimethoxy‐4‐propylthiophenethylamine (2C‐T‐7), 2,5‐dimethoxy‐4‐bromoamphetamine (DOB), 2,5‐dimethoxy‐4‐chloroamphetamine (DOC), 2,5‐dimethoxy‐4‐ethylamphetamine (DOET), 2,5‐dimethoxy‐4‐iodoamphetamine (DOI), 2,5‐dimethoxy‐4‐methylamphetamine (DOM), and 4‐methylthioamphetamine (4‐MTA). Analytical recoveries using solid‐phase extraction were 64–92% and the limit of detection was 0.5 ng/mL for all drugs except 2C‐B (1 ng/mL). The assay was evaluated in terms of analytical recovery, precision, accuracy, linearity, matrix effect, and interferences. The technique allows for the simultaneous detection of 15 psychostimulants at sub‐ng/mL concentrations. 相似文献
904.
Ariel I. Ahram 《Terrorism and Political Violence》2014,26(3):488-503
This article explains how and why armed, non-state actors collaborate with states to inflict massive levels of violence. Regime type and state capacity interact to provide state elites a menu of repertoires for implementing violence, some emphasizing direct state action, others emphasizing cooperation and alliance between state and armed, non-state actors. Rather than struggling in vain to build strong states to eliminate armed non-state actors and establish a monopoly over the use of force, averting genocide might necessitate recruiting and strengthening the power of indigenous, armed non-state actors. 相似文献
905.
Jérémy Carlier M.Sc. Emmanuel Escard M.D. Michel Péoc'h M.D. Ph.D. Baptiste Boyer M.D. Ludovic Romeuf M.Sc. Thierry Faict M.D. Ph.D. Jérôme Guitton Pharm.D. Ph.D. Yvan Gaillard Pharm.D. Ph.D. 《Journal of forensic sciences》2014,59(3):859-864
In March 2009, the body of a 51‐year‐old man was found in the boot of his car. The body had been frozen before being dismembered at the abdomen. The autopsy failed to determine the cause of death. Systematic toxicological analyses of the victim's peripheral blood and urine showed the presence of atropine, a powerful anticholinergic. Atropine was therefore specifically detected and quantified throughout the victim's biologic samples by HPLC‐MS² in the biologic fluids and UHPLC‐MS² in the hair. The atropine concentrations were 887 ng/mL in the cardiac blood, 489 ng/mL in the peripheral blood, 6693 ng/mL in the gastric contents (1.1 μg), 6753 ng/mL in the urine, and 2290 pg/mg in the hair. The blood concentrations measured in the decedent were consistent with an overdose of atropine, which was determined as the cause of death. The manner of death was a homicide with criminal intent. 相似文献
906.
目的建立了鸦片中吗啡、可待因、蒂巴因、罂粟碱、那可汀5种常量生物碱和牛心果碱、劳丹宁、劳丹素等12种痕量生物碱同时分离鉴定的超高效液相色谱-高分辨四极杆飞行时间串联质谱(UPLC/Q-TOF)方法。方法采用Agilent Eclipse Plus C18RRHD(2.1 mm×100 mm,1.8μm)色谱柱,以10 mM甲酸铵溶液和乙腈体系梯度洗脱,使用ESI离子源,正离子模式下采集数据。结果借助UPLC的快速分离和Q-TOF-MS测定的精确分子量和二级碎片信息,实现了17种生物碱的检测。应用SIMCA-P软件对78份国产鸦片和200份缅甸产鸦片进行偏最小二乘法判别分析(partial least squaresdiscriminate analysis,PLS-DA),比较不同地区鸦片样品中生物碱的差异,建立了区分国产鸦片和缅甸产鸦片的判别方法。结论所建立的方法用于鸦片样品中常量和痕量生物碱的检测及鸦片样品的产地判别,具有快速、高效、灵敏、准确的特点。 相似文献
907.
目的对裂解气相色谱-质谱法分析橡胶的裂解条件进行优化,研究利用橡胶特征裂解产物鉴别轮胎胎面胶。方法采用裂解气相色谱-质谱法,确定对NR、BR、SBR的裂解条件及其特征裂解产物,然后根据特征裂解产物及其相对含量并结合聚类分析,对38种轮胎胎面胶进行区分鉴别。结果确定了裂解温度590℃、裂解时间15s及三种橡胶的特征裂解产物;将38个轮胎胎面胶样品的主体成分归为4类,其中NR类5个、SBR类12个、NR/BR并用类5个、NR/SBR并用类16个,且能够对大部分并用类轮胎胎面胶进行鉴别。结论通过优化裂解条件,裂解产物重复性好,特征裂解产物明显,能够确定轮胎胎面胶的主体成分类别并能对大多数并用类轮胎胎面胶样品进行区分鉴别。 相似文献
908.
Munchelou M. Gomonit BS Britni Skillman PhD Madeleine J. Swortwood PhD 《Journal of forensic sciences》2024,69(2):678-687
There has been burgeoning interest in psilocybin-use for the treatment of various neurological and neurodegenerative diseases. Psilocybin is mistakenly perceived as the principal pharmacologically active compound due to its high concentrations found in magic mushrooms; however, it is the prodrug of psilocin. Despite the expanding body of clinical research seeking to understand the pharmacodynamic/pharmacokinetic properties of psilocin, and its role in inducing dramatic changes to cognitive function, there has not been a corresponding increase in the development of sensitive analytical methods that can quantify psilocin in different biological fluids. Existing analytical methods have been developed using plasma, serum, and urine as the matrix of choice, but with the unknown blood-to-plasma ratio of psilocin, any pharmacokinetic conclusions drawn solely on plasma data may be misleading. Thus, the main objective of this study is to develop the first analytical method that utilizes SPE and LC–MS/MS to quantify psilocin in human whole blood. The SPE procedure yielded a high recovery efficiency (≥89%) with minimal matrix effects. The method was validated according to ANSI/ASB 036 guidelines. Linearity was between 0.7–200 ng/mL and encompassed previously reported ranges found in plasma/serum. Bias, within- and between-run precision for all quality controls met ANSI/ASB 036 acceptability criteria. Endogenous/exogenous interferences and carryover were negligible. Psilocin stability was assessed at 4°C over 48 h and was considered stable. Although a proof-of-concept study will need to be performed to characterize the method, this analytical workflow was able to detect and quantify psilocin in human whole blood at low limits of quantification. 相似文献
909.
姚桓 《中国延安干部学院学报》2014,(1):64-67,26
本文从人民群众创造历史、党的领导作用、领导方法、作风建设、民主监督等五个方面对毛泽东关于群众路线的思想进行了梳理,阐述了其当代价值特别是对改革开放的指导作用. 相似文献
910.
李恒 《山西警官高等专科学校学报》2014,(3):71-74
构建和谐警民关系,是我们党的根本宗旨,也是公安工作的本质要求,同时是新形势下做好社会稳定工作的根本保证。构建四川藏区和谐警民关系是贯彻公安机关群众路线教育实践活动的组成部分,而要实现四川藏区警民关系和谐,就要提高破案率,增强藏区群众安全感;疏通警民沟通渠道,拉近藏区警民距离;加强藏区社会管理与群众工作的协调配合。 相似文献