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181.
目的应用DNA条形码片段ITS2对新型毒品样品中的植物成分进行分析。方法提取可疑毒品样本"spike99","K2","7号"中的植物基因组DNA,用ITS2通用引物进行扩增,对扩增产物进行测序,对序列校对拼接,应用BLAST方法在NCBI数据库中比对。结果 "spike 99"、"7号"各得到1条ITS2基因序列,"K2"得到2条ITS2基因序列,分别与紫花苜蓿、大麻、啤酒花、黄蜀葵的ITS2基因序列的同源性为100%。结论应用条形码技术可以成功分析新型毒品中的植物种属,为案件中植物样本的种属鉴定提供方法。  相似文献   
182.
In forensics, bloodstains on dark fabrics might be invisible for the naked eye. Although several visualization, presumptive, and confirmatory blood tests have been developed, all have one or more disadvantages, especially on DNA analysis. We report here the use of a visualization assay that can visually detect blood drops up to 1/20 dilution. In this assay, the fabric is placed between two wet filter papers and covered by glass surfaces on both sides. Pressure is applied on the glass surfaces in which bloodstains transfer onto the filter papers through capillary forces. Detected stains can be tested with other more sensitive presumptive blood tests performed on the filter paper. Even more, DNA analysis can be performed on the transferred bloodstains. The presented visualization assay is easy to perform, extremely cheap, requires little hands on time, and does not affect bloodstain pattern analysis.  相似文献   
183.
临床医学中的知情同意权是医学实践中由基本伦理上升为受法律保障的患者权利,通过告知同意书的契约形式表达。法医临床鉴定中的被鉴定人与医疗体系中的患者具有类似的法律地位,但尚无相应的法律法规赋予被鉴定人知情同意权。笔者建议法医临床学鉴定中可赋予被鉴定人一定的知情同意权,在与鉴定机构的契约化关系下,参与鉴定过程,知悉必要的鉴定信息,并对鉴定意见有选择性同意权,从而实现司法鉴定程序的公平、正义。  相似文献   
184.
目的建立15个基因座五色荧光复合扩增体系,并调查新疆维吾尔族的遗传多态性。方法筛选STR基因座,等位基因测序后按照重复序列重复次数命名,对建立的15个基因座五色荧光复合扩增体系进行灵敏度、种属特异性、同一性及稳定性检测,对新疆维吾尔族群体进行遗传多态性分析,与西藏藏族、岫岩满族、广州汉族进行群体间比较。结果建立了15个基因座复合扩增体系,检测灵敏度为0.3 ng,具有良好的种属特异性、同一性和稳定性。新疆维吾尔族13个常染色体STR基因座的基因频率分布符合Hardy-Weinberg平衡,无连锁不平衡现象,大部分基因座在群体间差异具有统计学意义。结论建立的体系具有法医物证学应用价值,13个常染色体STR基因座在新疆维吾尔族群体多态性高,适合于亲子鉴定及个人识别,可作为现有基因座的补充。  相似文献   
185.
目的探讨高坠案件中局部机械性损伤行为心理分析与死亡性质的关系,为此类案件的定性提供参考。方法收集2008—2013年高坠死亡案件311例,其中存在高坠难以形成的局部机械性损伤案例205例。对损伤形成特点、现场痕迹、高坠致命伤、文字信息等进行分析。结果 205例中,根据初步现场痕迹、高坠致命伤、文字信息等分析后,明确自杀86例,意外24例,性质不明95例。95例性质不明案例经对局部机械性损伤进行行为心理分析后,认定自杀80例,意外11例,他杀4例。结论高坠难以形成的局部机械性损伤与死亡性质具有关联性,根据局部机械性损伤行为心理分析推断高坠死亡性质基本准确。  相似文献   
186.
Methoxetamine (MXE) is a new synthetic drug of abuse structurally related to ketamine and phencyclidine. A case of a 29-year-old male with acute toxicity related to the analytically confirmed use of MXE is reported. The man was found dead at his residence. Biological material was analyzed using liquid chromatography–tandem mass spectrometry. The concentration of MXE in urine of the deceased was 85 μg/mL. Despite the vial containing the blood sample being destroyed during transportation and the blood leaking out into the cardboard packaging, the blood level of MXE was estimated. After determination of the cardboard grammage (approx. 400 g/m3) and the mean mass of the blood obtained after drying (0.1785 ± 0.0173 g per 1 mL), the estimated blood concentration of MXE was found to be 5.8 μg/mL. The high concentration of MXE in blood and urine and the circumstances of the case indicate an unintentional, fatal intoxication with this substance.  相似文献   
187.
Since 1998, over 5500 people have died while attempting to cross the U.S.–Mexico border without authorization. These deaths have primarily occured in the Arizona desert. Despite the high volume of deaths, little experimental work has been conducted on Sonoran Desert taphonomy. In this study, pig carcasses were used as proxies for human remains and placed in different depositional contexts (i.e., direct sunlight and shade) that replicate typical sites of migrant death. Decomposition was documented through daily site visits, motion-sensitive cameras and GIS mapping, while skeletal preservation was investigated through the collection of the remains and subsequent faunal analysis. Our results suggest that vultures and domestic dogs are underappreciated members of the Sonoran scavenging guild and may disperse skeletal remains and migrant possessions over 25 m from the site of death. The impact of scavengers and the desert environment on the decomposition process has significant implications for estimating death rates and identifying human remains along the Arizona/Mexico border.  相似文献   
188.
There have been periodic electronic news media reports of potential bioterrorism-related incidents involving unknown substances (often referred to as “white powder”) since the 2001 intentional dissemination of Bacillus anthracis through the U.S. Postal System. This study reviewed the number of unknown “white powder” incidents reported online by the electronic news media and compared them with unknown “white powder” incidents reported to the U.S. Centers for Disease Control and Prevention (CDC) and the U.S. Federal Bureau of Investigation (FBI) during a 2-year period from June 1, 2009 and May 31, 2011. Results identified 297 electronic news media reports, 538 CDC reports, and 384 FBI reports of unknown “white powder.” This study showed different unknown “white powder” incidents captured by each of the three sources. However, the authors could not determine the public health implications of this discordance.  相似文献   
189.
Forensic anthropologists are regularly asked to assist with the identification of unknown individuals using comparative medical radiography. This study addressed the use of midline medical sternotomy wires as a means for personal identification. Antemortem and postmortem radiographic comparisons were completed by 46 professional forensic anthropologists and anthropology graduate students familiar with comparative medical radiography as a technique for assessing identification. Participants were asked to make five radiographic matches from a pool of 20 radiographs. Participants also completed an anonymous survey detailing their education level and experience making radiographic comparisons. Participants were 99.5% accurate in matching the radiographs. Sensitivity was 98.7%, and specificity was 99.7%. Logistic regression analysis found no statistically significant differences in the participants' ability to make a correct match. As the high accuracy rates indicate, the shape, size, and various characteristics of the sternotomy wires are individualizing and can confidently be used when assisting with personal identification cases.  相似文献   
190.
This paper presents the case of a cadaver buried in a pine grove, in loamy soil at a depth of about 1.8 m. The case is quite interesting due to the fact that one hand of the victim was bare and the other one was clad in a latex glove. In the laboratory, the severed hands were gently washed with water. The left palm exhibited signs of advanced decomposition. The ridges were visible only on the thumb. The gloved hand was found to be in much better condition. There were signs of saponification on the palm. Ridges on both the palm and all fingers were visible. The fingers of the right hand, palm prints, and the thumb of the left hand were successfully matched against a ten-print card. The match provided the police with a positive identification of the missing person.  相似文献   
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