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41.
S. Strano-Rossi A. Bermejo-Barrera M. Chiarotti 《Forensic Science International Supplement Series》1995,70(1-3)
Segmental hair analysis was performed to obtain information about the history of drug abuse of subjects in a rehabilitation programme. The analytical data from hair samples were correlated, when possible, with urine analysis and to toxicological anamnesis. Toxicological analysis of hair seems to be a valid tool in this specific field. 相似文献
42.
When examining concentration relationships of doses it must be taken into account that hair growth is irregular. Hair growing from the shaved skin after a single dose of a certain drug cannot possibly contain the same concentration as hair after the same dose that has not been cut over a long period. Concentrations can even change during the hair growth in cases where the hair had been cut a couple of months before the hair sample was taken. The variations in the expected concentrations can exceed 20%. On the other hand, the evaluation of a hair tuft which has grown after the last drug consumption may be important in forensic cases where the hair which has grown earlier is not available. This may lead to misinterpretations at low concentrations. Expected concentrations are calculated assuming a telogen part of 10%. 相似文献
43.
目的改进滤纸血痕DNA提取方法,建立更简便、廉价,适合当前DNA建库需要的提取方法。方法将752份滤纸血痕分成四组,分别按照四种不同的Chelex-100法进行DNA提取并进行比较研究;63份新鲜血痕分别按照两种方法提取并进行对比研究。结果对于陈旧滤纸血痕,四种提取方法的检测成功率无显著差异(P>0.05);对于新鲜血痕,两种提取方法的检测成功率有显著差异(P<0.05)。结论对于建库陈旧滤纸血痕样本的DNA提取可采用不加纯水处理,直接加入Chelex-100的方法进行。 相似文献
44.
目的建立尿液中丁丙诺啡提取方法。方法尿液加pH 7.0缓冲液后,用三氯甲烷进行液相萃取或加pH 10.8缓冲液后,用401有机担体作吸附剂、三氯甲烷作洗脱剂进行固相萃取,GC/NPD法检测。结果尿液中丁丙诺啡液相萃取萃取率可达86.6%以上,固相萃取可达83.0%以上。结论两种提取方法萃取率高,可用于尿液中丁丙诺啡的提取。 相似文献
45.
Chelex法和两种磁珠法提取接触DNA效果的比较 总被引:1,自引:0,他引:1
目的比较Chelex法、DNA IQ磁珠法、EQ国产磁珠法对接触DNA的提取效果。方法将稀释为10ng、100ng的标准品DNA,分别采用Chelex法、DNA IQ磁珠法、EQ国产磁珠法处理;对30例烟蒂和30例牙刷分别采用Chelex法、DNA IQ磁珠法和EQ国产磁珠法提取DNA,然后进行PCR定量和STR检测。结果Chelex法对DNA的提取无损失,DNA IQ磁珠法、EQ国产磁珠法对DNA的提取均有不同程度的损失;烟蒂、牙刷等检材采用Chelex法提取的接触DNA量和IPC CT值显著高于IQ磁珠法、EQ国产磁珠法,但STR检验成功率却低于IQ磁珠法、EQ国产磁珠法。2种磁珠法提取的DNA量、IPC CT值和STR检验成功率无显著性差异。结论污染轻、杂质少的接触DNA检材,用Chelex法提取最为方便快捷;IQ磁珠法、EQ国产磁珠法更适合污染接触DNA检材的提取及自动化操作。 相似文献
46.
Biao Li M.Sc. Feng Bai M.Sc. Huayan Mu M.Sc. Ren Bao B.Sc. 《Journal of forensic sciences》2014,59(3):793-799
Inkpad seals are often placed on important documents, and determining the date when a seal was affixed can be important to assess the authenticity of a document. In this study, three different brands of inkpads and four different types of paper were used to make diachronic samples of the seals. A double‐solvent extraction method was employed to date the inkpad seals by comparing extraction rates with inks of known age. Cyclohexane was selected as a weak solvent, and chlorobenzene was selected as a strong solvent. After testing, curves were created to show the relationship between the extraction percentage of ink and the date of the seals. The experimental results showed that the extraction rate method was applicable for the relative dating of inkpad seals in some cases where the seal was placed on the document within 6 months. 相似文献
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Alessandro Mameli M.S. Gavino Piras B.S. Giovanni Delogu Ph.D. 《Journal of forensic sciences》2014,59(2):470-473
A universal method allowing for DNA profiling from bones exposed to seawater has not been reported yet. This study refers on the identification of a body immersed in seawater for 8 months. The biological material for identification was the mandibular body, usually characterized by low success rates of DNA analysis. Initially, two extraction protocols were performed with negative results: one used for bones immersed in fresh water and a silica‐column procedure. A third protocol was performed, which combined the extraction of a higher amount of bone powder, the use of multi‐silica‐based extraction columns followed by a concentration step. This protocol allowed to obtain low copy number DNA and to generate a 12‐loci STR profile by combining conventional STR typing and mini‐STR technologies. This protocol could be suitable when human bones have been exposed to severe environmental conditions, and the available nuclear DNA is highly degraded and in low copy number. 相似文献
50.
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