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31.
目的探索有效区分月经血和外周血的miRNA最优标记组合及最佳分类模型,并构建简便快速的自动化判别软件。方法对10种miRNA(miR-451a、miR-205-5p、miR-203a-3p、miR-214-3p、miR-144-3p、miR144-5p、miR-654-5p、miR-888-5p、miR-891a-5p、miR-124-3p)在200余份月经血和外周血样本中的相对表达量以实时荧光定量PCR检测,并以7种算法模型(核密度估计、K-最近邻、逻辑回归、线性判别分析、支持向量机、神经网络、随机森林)进行数据分析,选出鉴别效果最好的标记组合及算法模型,进而构建自动判别软件。结果月经血和外周血中差别最大的三种miRNA为miR-205-5p、miR-203a-3p和miR-214-3p,使用miR144-5p与上述miRNA中的一种或两种组合可达较好区分效果,其中基于miR-144-5p、miR-203a-3p和miR205-5p所形成的“最优特征项组合一”稳健性最强。7种算法模型中最佳分类模型为核密度估计模型,其次为逻辑回归模型。结论本研究建立的自动判别软件界面友好、使用简单,适合辅助法医检验关于月经血和/或外周血判别分析的计算,便利于法医物证工作,有较大的推广应用价值。  相似文献   
32.
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   
33.
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   
34.
In some countries, it is illegal to drive with any detectable amount of alcohol in blood; in others, the legal limit is 0.5 g/L or lower. Recently, some defendants charged with driving under the influence of alcohol and have claimed that positive breath alcohol test results were due to the ingestion of homeopathic mother tinctures. These preparations are obtained by maceration, digestion, infusion, or decoction of herbal material in hydroalcoholic solvent. A series of tests were conducted to evaluate the alcoholic content of three homeopathic mother tinctures and their ability to produce inaccurate breath alcohol results. Nine of 30 subjects gave positive results (0.11–0.82 g/L) when tests were taken within 1 min after drinking mother tincture. All tests taken at least 15 min after the mother tincture consumption and resulted in alcohol-free readings. An observation period of 15–20 min prior to breath alcohol testing eliminates the possibility of false-positive results.  相似文献   
35.
Research into maximizing the speed, precision, and reliability of estimating the postmortem interval (PMI) has been a recurring object of investigation and methodologies based on the vitreous humor (VH) have provided good results. However, contamination from causes not readily apparent, such as blood, can occur, and thus lead not only to an erroneous estimation of PMI, but also interfere with the correct identification of other substances in the VH. We have developed a flow cytometry method which quantifies blood contamination and is able to detect erythrocytes in 1:750,000 dilution of contaminated VH which affects the results of hypoxanthine. It is an improvement on the previous more complex mass spectrometry method, being faster, more sensitive, and readily available. As such, it could be proposed for the rapid screening of appropriate samples by detecting and eliminating blood contaminated samples from PMI estimation.  相似文献   
36.
现代生殖技术的问世大大冲击了人类传统的自然生殖方式,与此同时,也冲击了现代伦理观念,并带来了一系列法律问题。随着人工生殖子女数量的增多,相关法律纠纷也日益增多。因此,本文对于人工生殖的一个基本问题———人工生殖子女的法律地位进行了深入的探讨。着重论述了人工生殖子女的分类,相应的父母子女关系的确定及权利义务关系。同时对代孕母亲所引发的法律问题进行了探讨。  相似文献   
37.
The introduction of a standardized paternity index (PI) for the statistical evaluation of blood group findings in cases of disputed paternity is proposed and explained. By using the PI XY as parameter, it is not necessary to give the information of the probability of paternity in percent. The PI includes the full information of the blood group findings. In addition to that, by using the suggested standardization based on the probabilities of error according to Schulte Mönting and Walter the test volume is also taken into account. The interpretation of the mathematical result is given by verbal predicates, the limitations of which are orientated by the verbal predicates for the probabilities of error according to Schulte Mönting and Walter, published by us elsewhere. Besides the essential fact that the test volume is taken into account, the most important advantage of this procedure is that the mathematical result is involved in the court decision only by the PI (which is free of any valuation) and its verbal predicate and not by sometimes relatively high percentages, which may be misunderstood by laymen.  相似文献   
38.
本文报告理化因素对抗人N单克隆抗体(ON_1D_3)活性的影响。P~H及反应温度对ON_1D_3单克隆抗体与人红细胞的血凝反应有显著的影响。较适宜的实验条件为P~H7.0,温度30℃。在此条件下对155例新鲜血液及60例陈旧血痕样品进行MN分型。结果与用市售兔抗N血清测定的结果完全一致,证明在上述条件下,ON_1D_3单克隆抗体可用于临床常规血液分型及法医学上对陈旧血痕MN血型的测定。  相似文献   
39.
建立70%乙醇灌胃致大鼠胃粘膜急性损伤模型,以胃粘膜血流量,胃跨壁电位差,胃粘膜损伤指数为指标,并测定血液中,胃粘膜中一氧化氮含量,研究针灸对胃粘膜损伤的保护作用及其与NO的关系。结果显示:针灸对胃粘膜损伤具有保护作用。NO的前体L-精氨酸和NO的代价供体硝普钠对胃粘膜也有保护作用,而NO合成酶的抑制剂N-亚硝基左旋精氨酸未显示出胃粘膜有保护作用。  相似文献   
40.
月经血鉴定与基质金属蛋白酶-11   总被引:1,自引:0,他引:1  
Zheng J  Lu HL  Chen S 《法医学杂志》2006,22(1):I0001-I0003
月经血鉴定是法医血痕检验的内容之一。本文就月经血鉴定的几种经典方法进行回顾,并分析其应用局限性。基质金属蛋白酶-11是一种能降解细胞外基质的水解蛋白酶,有研究提示基质金属蛋白酶-11以其在月经血中表达的特异性和检测方法的灵敏性有可能成为对月经血鉴定的新一代标志物。本文对基质金属蛋白酶-11的结构、功能、在月经血鉴定中的应用及展望进行综述。  相似文献   
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