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81.
Zhan L  Zhao ZQ  Shan YW 《法医学杂志》2005,21(2):113-114
目的根据机体死后组织细胞DNA降解规律,研究其与死亡时间之间的关系.方法SD大鼠处死后,在不同死亡时间段取肝、肾、脾组织提取DNA.根据DNA3′末端转移的方法(TdT法)将dUTP结合到DNA的3′末端,检测反应剩余的dUTP量,从而推测机体死后不同时间段DNA的降解情况.结果经对剩余dUTP检测发现,dUTP的剩余量随死亡时间延长而减少,说明DNA降解与死亡时间存在一定的关系.结论根据机体死后DNA降解规律可用于早期死亡时间的推测.  相似文献   
82.
目的应用Ion Torrent PGM~(TM)测序系统对人线粒体DNA(mitochondria DNA,mtDNA)全序列进行分析检测,研究不同组织间mt DNA序列差异情况。方法通过法医尸体检验采集6名无关个体的组织样本,包括胸腔血液、头发、肋软骨、指甲、骨骼肌和口腔上皮。使用4对引物对线粒体全序列进行扩增,应用Ion Shear~(TM)Plus Reagents试剂盒和Ion Plus Fragment Library试剂盒等构建文库,并在Ion Torrent PGM~(TM)测序系统上进行线粒体基因组全序列测序,并针对异质性位点和在HVⅠ区域突变位点,进行Sanger测序验证。结果所有样本的全基因组mtDNA都扩增成功,6名无关个体分属于6种不同的单倍型,同一个体不同组织之间mtDNA存在异质性差异。异质性位点和HVⅠ区域突变位点采用Sanger测序结果均得到验证。通过Kappa统计方法进行一致性检验后发现,相同个体不同组织的mtDNA序列检验结果仍具有较好的一致性。结论本研究所采用的人线粒体基因组全序列的测序检验方法,可以检测出同一个体不同组织间mtDNA的异质性差异,该差异具有较高的一致性,该结果对mtDNA在法庭科学中的应用具有指导作用。  相似文献   
83.
The Correctional Service of Canada implemented a urine drug-screening program over 10 years ago. The objective of this report is to describe the program and drug test results in this program for 1999. Offenders in Canadian federal correctional institutions and those living in the community on conditional release were subject to urine drug testing. Urine specimens were collected at correctional facilities and shipped by courier to MAXXAM Analytics Inc. laboratory. All urine specimens were analyzed for amphetamines, cannabinoids, cocaine metabolite (benzoylecgonine), opiates, phencyclidine, benzodiazepines, methyl phenidate, meperidine, pentazocine and fluoxetine by immunoassay screening (homogeneous EIA and ELISA assays) followed by GC-MS confirmation. Ethyl alcohol was analyzed when specifically requested. Alternative screening and confirmation methods with lower cut-off values were used, whenever urine specimens were dilute (creatinine <20mg/dl and specific gravity 相似文献   
84.
85.
大鼠脑挫伤后FN表达与损伤时程关系的研究   总被引:3,自引:2,他引:3  
为寻找推断脑损伤经历时间的可靠指标,采用自制自由落体撞击法致大鼠右顶叶局灶性脑挫伤模型,于不同时间段处死大鼠后,进行纤维连接蛋白的免疫组织化学及原位杂交法研究,结果发现纤维连接蛋白及其 mRNA表达水平与伤后经历时间有一定相关性,并能较好地鉴别死前脑挫伤和死后脑挫伤,可作为推断脑挫伤经历时间的参考指标之一。  相似文献   
86.
  总被引:3,自引:0,他引:3  
Nine Y-STR loci from the \"minimal haplotype\" included in Y-STR Haplotype Reference Databases (YHRD) together with eight additional Y-STRs (DYS437, DYS438, DYS439, DYS460, DYS461, GATA C4, GATA H4 and GATA A10) were analyzed in a sample of 101 males from Equatorial Guinea living in Madrid. Haplotype and allelic frequencies were calculated and genetic diversities were estimated for each genetic system as well as for the whole haplotype. An unexpected high frequency (6%) of intermediate alleles (13.2 and 14.2) was found in DYS385. For DYS19, two alleles were found in one sample. Another sample failed to amplify with DYS393 primers using either PowerPlex Y System (Promega Corporation) or the Y-PLEXtrade mark 12 (Reliagene, New Orleans, LA) commercial kits. Comparison between Equatorial Guinea and another African population (Mozambique; South East Coast) revealed a significant pairwise Phi(st) value between them (Phi(st)=0.03309; P=0.00000).  相似文献   
87.
    
India is the home to five of the eight majestic big cats of the world. The three major big cats namely, lion, tiger, and leopard are listed in the Schedule I of the Indian Wildlife Protection Act, 1972. Apart from the severe loss of the habitat, these are continuously facing the danger of extinction mainly due to poaching and hunting for their body parts, which are being greatly valued by apothecaries marketing traditional Chinese medicines. With the advent of polymerase chain reaction (PCR), DNA-based markers have emerged as major tools in the arena of wildlife forensics. Microsatellites (short tandem repeats, STRs) are markers of choice because of their polymorphic and co-dominant nature. These strictly follow the Mendelian inheritance and are highly reproducible. We have identified a new microsatellite (STR) locus Ple 46, which shows amplification in a species-specific manner (size of STR) in all the members of the family felidae studied here. This PCR-based, non-invasive method opens a new avenue to forensic identification of big cats.  相似文献   
88.
    
The possibility of detection of lead-antimony-barium aggregates from non-firearm sources is confirmed according to the tests performed on brake pads, and firework and automobile workers. Moreover, information on particles taken from cartridge cases shows the relative feeble importance of the morphology in distinguishing gunshot residues (GSRs). Furthermore, also the presence in the spectrum of other elements (e.g., iron) is not so conclusive. In this panorama, the possibility of discriminating gunshot residue particles from other non-firearm lead-antimony-barium aggregates is investigated: the proposed method is based on X-ray mapping technique--currently applied used in Reparto Carabinieri Investigazioni Scientifiche in Rome, the forensic service of Italian Carabinieri--according to which the spatial distribution of the emission energy of each element of the sample is pictured. Gunshot residues present the same lead-antimony-barium distribution (or at least the same antimony-barium distribution with lead nodules), as some other environmental occupational aggregates do not (different plaques of lead, antimony, and barium). So, X-ray mapping technique can offer a new fundamental evaluation parameter in analysis of gunshot residues with scanning electron microscopy/energy-dispersive (SEM/EDS) spectrometry, and new standards could be considered.  相似文献   
89.
    
Allele frequencies for 15 short tandem repeats (STRs) autosomal loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818 and FGA, included in the AmpFLSTR Identifiler, Applied Biosystems) were studied in the city of Maracaibo, Venezuela and were compared with other published Latin-American populations for the same loci. Population and forensic parameters were estimated.  相似文献   
90.
    
A method for the simultaneous determination of cocaine (COC) and cocaethylene (CE) in human hair was developed, using solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) as analytical technique to identify and quantify the drugs. Selected ion monitoring (SIM) mode was used to obtain higher sensitivity. The deuterated-labeled analogues were used as internal standards. The detector response was linear for the drugs studied over the range 0.4-15 ng/mg, with correlation coefficients higher than 0.995. The coefficients of variation oscillated between 0.65% and 14.18% and the accuracy was in the range from 0.73% to 11.20%. The limits of quantitation and detection were found to be acceptable. Finally, this method was applied to 15 hair samples from cocaine users, obtaining positive results in all cases. The mean concentrations were 5.39 ng/mg (range: 0.43-8.98 ng/mg) for cocaine and 1.11 ng/mg (range: 0.42-2.23 ng/mg) for cocaethylene.  相似文献   
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