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51.
人体内乙醇含量检测的影响因素分析   总被引:2,自引:2,他引:0  
人体内乙醇含量检测不仅是法医鉴定工作中常规检测项目,也是交通肇事案件最终的仲裁依据,其检测结果直接影响着受检人员的责任判罚。本文根据乙醇的毒理特征及在人体内的代谢过程,就不同检材、送检时效性、尸体腐败、血液检品中不同成分和保存方式、以及检测结果的不确定度等对乙醇含量检测结果的影响进行分析,以利于对受检者是否饮酒及其程度做出科学、公正的判定。  相似文献   
52.
目的比较7种一氧化碳中毒血样分光光度含量测定方法的特点及适用性。方法用空白血添加一氧化碳配制不同浓度的样品,采用双波长法、还原法(3种)、切线法和导数光谱法(2种)进行检测,对各种方法线性范围、重现性和操作中注意事项等内容进行考察,并用实际案件检材验证和比较。结果还原法一在30%~70%、还原法三在20%~100%,其他方法在20%~70%范围内,线性关系良好;样本浓度超过或低于50%,采用切线法有一定误差;导数法及还原法三因需要制备CO饱和样本,操作略微繁琐,但导数光谱法计算结果准确性好。结论几种方法均可用于一氧化碳中毒血的检测,实验结果可为方法的实际应用提供借鉴和帮助。  相似文献   
53.
An HPLC‐DAD method was developed to detect and quantify a neonicotinoid insecticide acetamiprid (ATP) and its metabolite IM‐1‐2 in autopsy samples of a fatal intoxication case. The postmortem blood and tissue distribution of ATP and IM‐1‐2 was determined for the first time. The method showed acceptable precisions and recoveries with relative standard deviations of <10% for ATP level and 1.38 % for IM‐1‐2. The detection and quantification limits for ATP were 0.015 μg/mL and 0.030 μg/mL for blood and were 0.035 μg/g and 0.050 μg/g for liver samples, respectively. The mean contents of ATP were 0.79 μg/g in the liver, 47.35 μg/g in the stomach contents and 2.7 μg/mL in the blood. IM‐1‐2 content was 17.0 μg/g in the stomach contents. ATP and IM‐1‐2 were not detected in the urine. The presence of ATP and IM‐1‐2 in the samples was confirmed by GC‐MS. The method can be exploited in future forensic casework.  相似文献   
54.
目的:建立生物检材血液中农药的快速溶剂萃取(accelerated solvent extraction,ASE)法。方法通过优化ASE萃取条件,考察萃取温度、时间和萃取剂对回收率的影响,提取血液中的农药进行气相色谱-质谱联用(GC/MS)法定性定量分析。结果血液中8种农药的平均回收率在70.6%~92.4%,变异系数小于5.0%,8种农药在0.5~5.0μg/mL的浓度范围内线性良好。结论该方法具有操作简便快捷、回收率高、重现性好等特点,可用于农药的提取检验。  相似文献   
55.
本文以Web of Science核心文集库2001-2021年发表的353篇关于数字政府研究的文章为样本,运用Cite Space知识可视化软件,通过关键词共现图谱、关键词聚类图谱、演化路径知识图谱和关键词分析,总结了国外数字政府研究概况、国外数字政府研究热点聚类及其发展脉络。研究发现,从2001年起,国外数字政府经历了技术规制、智慧赋能和价值塑造三个阶段,包括十个重要研究聚类,可被分为知识促进、科技支撑、价值培养和合作体系四大主要研究内容。随着数字时代的新要求,数字科技革新和建设路径优化、公共数字伦理和数字素养提升、国家数字主权和公民数字保护预计将成为数字政府研究的热点问题。  相似文献   
56.
Fentanyl has emerged as the most prolific drug in the ongoing opioid epidemic and has greatly impacted traffic safety in recent years. This study aimed to evaluate fentanyl prevalence and concentrations in blood and oral fluid in driving under the influence of drugs (DUID) cases in three different regions (i.e., Alabama, Orange County, CA, and Houston, TX) from 2017 to 2022. Furthermore, traffic fatalities were evaluated for Alabama and Orange County, CA. Fentanyl positivity in DUID and traffic fatalities increased for most years in this study. In Alabama, the prevalence of fentanyl DUID cases increased 4-fold in 2022 compared to 2017. Orange County's increase from 2017 to 2022 was 14-fold. In Houston, the increase was approximately 2-fold from 2019 to 2022. The greatest increase for all laboratories coincided with the start of the COVID-19 pandemic. In 2022, the median fentanyl DUID blood concentrations were 4.7, 11, and 4.7 ng/mL in Alabama, Orange County, and Houston, respectively. Most fentanyl cases were polydrug cases (≥90%). Methamphetamine, THC, and alprazolam were the most frequently detected drugs in combination with fentanyl. Alabama has collected oral fluid and blood in DUID cases since 2018. The detection of fentanyl in oral fluid was comparable to blood. However, 59% and 8.7% of fentanyl-positive cases had concentrations of >20 ng/mL in oral fluid and blood, respectively. Therefore, oral fluid as an alternative or supplemental specimen to blood is an attractive approach for fentanyl in DUID cases. This study contributes to understanding recent fentanyl trends and their impact on traffic safety.  相似文献   
57.
The onus of proof in criminal cases is beyond any reasonable doubt, and the issue on the lack of complete internal validation data can be manipulated when it comes to justifying the validity and reliability of the X-chromosomal short tandem repeats analysis for court representation. Therefore, this research evaluated the efficiency of the optimized 60% reduced volumes for polymerase chain reaction (PCR) amplification using the Qiagen Investigator® Argus X-12 QS Kit, as well as the capillary electrophoresis (CE) sample preparation for blood samples on Flinder's Technology Associates (FTA) cards. Good-quality DNA profile (3000–12,000 RFU) from the purified blood sample on FTA card (1.2 mm) were obtained using the optimized PCR (10.0 μL of PCR reaction volume and 21 cycles) and CE (9.0 μL Hi-Di™ Formamide and 0.3 μL DNA Size Standard 550 [BTO] and 27 s injection time) conditions. The analytical and stochastic thresholds were 100 and 200 RFU, respectively. Hence, the internal validation data supported the use of the optimized 60% reduced PCR amplification reaction volume of the Qiagen Investigator® Argus X-12 QS Kit as well as the CE sample preparation for producing reliable DNA profiles that comply with the quality assurance standards for forensic DNA testing laboratories, while optimizing the analytical cost.  相似文献   
58.
The aim of this study was to develop chemical improvements to the original Weber protocol, in order to increase the intensity and time length of light emission and to eliminate false‐positive reactions. The intensity and duration of light were measured on serial blood dilutions using a plate reader chemiluminometer. Blood stains of various concentrations were impregnated in pure cellulose, dried, and luminol solution was added with/without the potential enhancers. An in silico study was also conducted, aiming to demonstrate the enhancing mechanism of hemoglobin denaturation using 8 M urea. The luminol blood detection test revealed important improvements after urea pretreatment or in the presence of monochloro‐triazinyl‐β‐cyclodextrin. This approach also eliminated the false‐positive reaction from sodium hypochlorite. These improvements could provide a higher sensitivity under particular circumstances such as old or washed blood stains, leading to a better localization for further DNA typing and higher quality photographic analysis.  相似文献   
59.
藏族是一个有着悠久历史和灿烂文化的民族,在长期的历史发展中,形成了独有的民族心理素质、民族情感、风俗习惯、政教合一的政治制度和自成体系的习惯法规。这些政治、经济和文化等方面的特征,随着民主改革和社会的进步而逐渐被削弱。但旧习惯法中的赔命价仍直接或间接地影响着国家法律的贯彻执行,产生了一系列执法活动中的矛盾和冲突。这就要求司法人员在执法过程中,采取一些特殊的政策和规定,以便妥善解决与藏族习惯法中的赔命价现象有关的特殊问题。  相似文献   
60.
Detection of blood on dark materials is difficult for crime scene examiners so presumptive tests are used to assist. This study compared the ability of luminol, leuko crystal violet, tetramethylbenzidine, and Combur Test®E to detect whole, diluted blood (1:100) and a key‐shaped blood transfer stain (1:10), on dark cotton sheeting, tea towel, socks, synthetic carpet, and car mats. Powdered bleach was used to evaluate specificity of the blood detection tests. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall misclassification rate (OMR) assessed the quality of the blood tests. Luminol was the preferred test for diluted blood having the highest sensitivity (79%–96%), NPV (66%–93%), and the lowest OMR (3%–15%). Luminol was also found to be most efficient with a testing time on 25 items of 2 h 50 min compared with up to 8 h. Overall, luminol was the most effective method, also providing information on bloodstain patterns.  相似文献   
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