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The inhalation of heroin vapors after heating on aluminium foil ("chasing the dragon") is gaining popularity nowadays among heroin users seeking to avoid the risks of parenteral drug administration. The heroin-smoking procedure was simulated under laboratory conditions by heating the samples on aluminium foil at 250 to 400 degrees C and collecting the vapors in a condenser trap. A total of 72 pyrolysis products of diacetylmorphine, street heroin, residues from aluminium foils used to smoke street heroin, typical by-products, and adulterants were detected by gas chromatography/mass spectrometry (GC/MS). About half of these compounds could be identified. Diacetylmorphine (base and salt) undergoes substantial to complete degradation. Some typical street heroin constituents, like morphine, codeine, acetylcodeine, papaverine, and caffeine, are rather heat-stable. Other compounds, like noscapine and paracetamol, are pyrolyzed to a greater extent. The principal chemical reactions leading to the formation of pyrolysis products are desacetylation, transacetylation, N-demethylation, O-methylation, ring cleavage and oxydation. 相似文献
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What is the best sample for determining the early postmortem period by on-the-spot flow cytometry analysis? 总被引:8,自引:0,他引:8
Di Nunno N Costantinides F Cina SJ Rizzardi C Di Nunno C Melato M 《The American journal of forensic medicine and pathology》2002,23(2):173-180
The level of degradation of DNA as a means for determining the time of death has been proposed as a valid adjunct to the classic thanatochronologic methods. The twofold aim of this work was to determine which organ might reveal both a correlation between the percentage of degradation of the DNA and the time lapse since death, and would be easiest to sample and yield the most reproducible results even in technically unfavorable situations such as on-the-spot investigations at the scene of death. A comparison of the spleen, blood, and liver showed that hepatic tissue best meets these specific needs because it shows a virtually linear correlation between the time elapsed since death and the level of degradation of the DNA, and it can easily be sampled at the scene of death by use of a common biopsy needle. 相似文献
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Trivedi R Chattopadhyay P Kashyap VK 《The American journal of forensic medicine and pathology》2002,23(2):191-196
A new method for better recovery of DNA suitable for amplification of hypervariable loci from fragments of teeth, consisting of two steps-scraping and aspiration, and extensive decalcification-is reported. Higher yields of high molecular weight DNA were obtained from the root, pulp, and crown of all kinds of 120 teeth, irrespective of gender, age, and source of teeth. HLA DQA1, 5 poly markers (LDLR, GYPA, HBGG, D7S8, and Gc), and other 12 short tandem repeat loci (HPRTB, F13B, LPL, D13S317, D7S820, D5S818, D21S11, D18S51, FGA, D8S1179, D3S1358, and vWA) could be successfully amplified and typed from recovered DNA. 相似文献
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This study is one of the very few, and the most extensive to date, which has examined deceptive behavior in a real-life, high-stakes setting. The behavior of 16 suspects in their police interviews has been analyzed. Clips of video footage have been selected where other sources (reliable witness statements and forensic evidence) provide evidence that the suspect lied or told the truth. Truthful and deceptive behaviors were compared. The suspects blinked less frequently and made longer pauses during deceptive clips than during truthful clips. Eye contact was maintained equally for deceptive and truthful clips. These findings negate the popular belief amongst both laypersons and professional lie detectors (such as the police) that liars behave nervously by fidgeting and avoiding eye contact. However, large individual differences were present. 相似文献
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目的构建重组pET28a-EDA-EDB质粒,制备重组纤维连接蛋白EDA-EDB融合蛋白。方法采用基因重组技术,将EDA、EDB基因片段连接,再将该重组基因插入pET28a表达载体,表达重组融合EDA-EDB蛋白后,利用6×His/Ni-NTA纯化系统进行纯化,免疫印迹法检测。结果成功连接EDA、EDB基因片段,重组pET28a-EDA-EDB质粒;在大肠杆菌BL21(DE3)中高度表达重组蛋白,获得较纯的重组蛋白,免疫印迹法证实为FN的组分。结论EDA-EDB重组蛋白能采用pET系统在大肠杆菌中表达,并可通过6×His/Ni-NTA纯化系统进行纯化而获得免疫原。 相似文献