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361.
传统型管理者是农村中的落后力量,底层精英是农村社会经济发展的中坚力量.传统型管理者与底层精英之间存在着诸多分歧和矛盾,二者的循环流动渠道的畅通与否直接关系到农村的稳定.  相似文献   
362.
目的采用液液提取-GC/MS法检测血液中米氮平。方法用0.1mol/L NaOH溶液调节血液pH值为8~9,以二氯甲烷∶环己烷(4∶6)混合溶剂作为提取溶剂,液液提取法提取血液中米氮平,外标法气相色谱/质谱联用仪定性定量分析。在2mL血中分别添加标准米氮平1、0.5、0.1μg,进行回收率测定。结果血液中添加米氮平的平均回收率为91.5%,方法的工作曲线为Y=1E+06X-16206,相关系数r=0.999 7,线性范围0.5~10μg/mL,最小检出限0.1μg/mL(S/N=46)。结论本文方法操作简便,适合于血液中米氮平的定性、定量分析,可在实际捡案中选择使用。  相似文献   
363.
目的建立巯基丁二酸修饰的水溶性碲化镉量子点溶液(MSA/CdTe QDs)显现多种客体表面的血潜指纹的方法。方法利用量子点对人体血液成分的特异性标识作用,365nm紫外光激发使其荧光显像。结果 MSA/CdTe溶液显现时间显著短于文献报导的同类方法;显现效果和灵敏度优于显现血潜指纹常用试剂四甲基联苯胺和氨基黑10B。结论水溶性MSA/CdTe溶液适于显现多种客体表面的血潜指纹,效果优异。  相似文献   
364.
Gunshot backspatter comprises biological material expelled backward through bullet entry holes. Crime scene investigators analyze backspatter patterns to infer wounding circumstances. An understanding of the mechanism of backspatter generation, and the relationship between spatter patterns and bullet and tissue characteristics, would enhance the predictive value of such analysis. We examined soft-tissue ballistic wounding responses to determine the underlying components and how these might be relevant to the generation of backspatter. We identified five mechanistic components to ballistic wounding (elastic, viscous, crushing, cutting, and thermal), each related to mechanical disciplines (respectively, solid mechanics, fluid mechanics, fracture mechanics, rheology, and thermodynamics). We identified potential roles for these five components in backspatter formation and provide a scenario whereby a sequence of events incorporating these components could lead to backspatter generation and expulsion. This research provides a framework for the mathematical representation, and subsequent computational predictive modeling, of backspatter generation and pattern formation.  相似文献   
365.
This study examines the survivability of human blood proteins in soils from a year and a half old ambush scene in Kosovo. A total of 72 soil samples were collected, a number of which were directly associated with bone fragments or bullet projectiles. The samples were examined using crossover immunoelectrophoresis (CIEP) to determine the presence of blood protein and species affiliation. Human blood proteins were identified in 44 of the 72 samples (61%) with the majority of the positive observations (29 of 44) found 0.0-4.5 cm below ground surface (65%). Chi-squared and two-sample difference of proportions tests confirmed significant differences between samples with and without associated physical evidence and the presence and depth of human blood proteins. While DNA has largely replaced immunological analysis in forensic analyses, our results suggest that in particular situations, CIEP may still be a valuable tool in criminology.  相似文献   
366.
目的建立人全血中25种精神药物快速测定的LC-MS/MS方法,并应用于分析杭州地区药物影响下驾驶(driving under the inference of drugs,DUID)情况。方法以乙腈沉淀蛋白,离心后取上清液,氮气流下吹干,残渣以初始流动相复溶,离心后取上清分析;采用C18色谱柱(50mm×3.0mm,2.6μm)分离,流动相:0.1%甲酸水(A相),乙腈:甲醇=1:1(B相),梯度洗脱;质谱检测,采用串联质谱电喷雾离子源,正电离扫描,多反应监测(MRM)。结果 25种精神药物在0.05~20ng/m L范围内线性良好,R=0.994 4~0.999 6;定量下限为0.05ng/m L;提取回收率为83.0%~99.7%;方法回收率为80.2%~97.4%;日内精密度(RSD)为1.6%~14%;日间精密度(RSD)为3.1%~14%。以该法测定杭州市公安司法鉴定中心留存的全血样品3140例,25种精神药物至少一种的检出率为3.7%。结论本方法灵敏、快捷、准确,适用于全血中25种精神药物快速检测。  相似文献   
367.
Knowledge concerning the distribution of methadone in postmortem human tissue and the effect of postmortem redistribution on methadone is today limited making the choice of a suitable substitute for femoral blood difficult when this is not available. Cardiac blood, femoral blood, muscle, and brain tissue concentrations of the enantiomers of methadone and its metabolite 2‐ethyl‐1,5‐dimethyl‐3,3‐diphenylpyrrolinium were recorded for 155 postmortem cases. Brain and muscle tissue concentrations exceeded the femoral blood concentrations with a median fold of 2.3 and 1.6, respectively, but both had a better correlation than cardiac blood to femoral blood concentrations. The Kruskal–Wallis test showed a significant dependency on time and body mass index for some of the matrix ratios over femoral blood. We conclude brain or muscle tissue may constitute a better alternative for measurement of methadone than cardiac blood for situations in which femoral blood is not available, despite concentrations in both matrices being systematically higher.  相似文献   
368.
目的调查湖南省一般人群血液中33种元素[锂(Li)、铍(Be)、硼(B)、镁(Mg)、铝(Al)、钙(Ca)、钛(Ti)、钒(V)、铬(Cr)、锰(Mn)、铁(Fe)、钴(Co)、镍(Ni)、铜(Cu)、锌(Zn)、镓(Ga)、砷(As)、硒(Se)、铷(Rb)、锶(Sr)、锆(Zr)、钼(Mo)、银(Ag)、镉(Cd)、锑(Sb)、铯(Cs)、钡(Ba)、金(Au)、汞(Hg)、铊(Tl)、铅(Pb)、钍(Th)、铀(U)]的正常值范围。方法采用电感耦合等离子体质谱法(inductively coupled plasma-mass spectrometry,ICP-MS)检测血液中33种元素,测定其正常值范围,并考察区域、性别和年龄对人群血液中元素含量的影响。结果建立了湖南省人群血液中33种元素的正常值范围,其中B、Mg、Ca、Ti、Mn、Fe、Co、Cu、Zn、As、Se、Rb、Sr、Ag、Cd、Cs、Hg和Pb在性别间差异具有统计学意义(P0.05)。女性因年龄不同有差异的元素有Co、Ni、Cs和Hg(P0.05),男性因年龄不同有差异的元素有Cu、Se和Hg(P0.05)。结论不同地区人群血液中元素含量存在差异,建立了湖南省四个市的正常值范围。  相似文献   
369.
Widmark calculations are the most commonly used alcohol calculations to estimate a) the amount of alcohol consumed based on blood alcohol concentration (BAC) and b) BACs at a set time after consumption of a known amount of alcohol. These calculations are vital in forensic casework. Previous work has demonstrated that using general error propagation-based equations the variability associated with alcohol calculations can be estimated, but these equations have only been determined for the volume of distribution version of the Widmark equation. However, recent investigations have shown that the total body water (TBW) version of the Widmark equation is more reliable than the version that utilizes the apparent volume of distribution of ethanol. To date, there is no general error propagation equation to determine the variability associated the TBW version of the Widmark equation. Using previously published studies of 185 individuals in which alcohol elimination rate (β) and ethanol's volume of distribution were determined, we have shown that there is a negative correlation (?0.247) between the alcohol elimination rate (β) and TBW. Using these data, we were able to produce equations allowing the estimation of the variability of the results calculated using the TBW version of the Widmark equation. This will allow forensic practitioners to give the best determination of the variability associated with Widmark calculations currently possible.  相似文献   
370.
This article examines the governmental apparatus organised around Singapore's Blood Transfusion Service (SBTS) and the knowledge, experts and techniques associated with transfusion medicine. I term this apparatus, which was in place in the Singapore from its first steps towards political independence in 1959 until 1990, ‘Singapore's haemato-logic assemblage’. Drawing on the work of Foucault, the article explores how this assemblage overflowed into and reconfigured understandings of biological sociality and citizenship in post-colonial Singapore. More specifically, it argues that, in the 30 years following independence, this assemblage brought into being a new figure of the biological citizen by creating a sphere of possibilities for Singaporeans to think and act accordingly. This new figure of the citizen is ‘the blood donor’. Articulated around the SBTS and the knowledge and techniques of transfusion medicine, this donor is a Singaporean who gives blood to save the lives of fellow citizens and participates, thereby, in the development and modernisation of the newly independent nation. To substantiate this argument, the article shows how the haemato-logic assemblage helped to realise this new figure of the citizen by creating – through narratives, statistics, spaces and rewarding schemes – a sphere of possibilities in which Singaporeans could think and act as blood donors.  相似文献   
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