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911.
Mura P Chatelain C Dumestre V Gaulier JM Ghysel MH Lacroix C Kergueris MF Lhermitte M Moulsma M Pépin G Vincent F Kintz P 《Forensic science international》2006,160(2-3):168-172
A collaborative study was conducted in France in order to determine the prevalence of cannabinoids, opiates, cocaine metabolites and amphetamines in blood samples from drivers killed in road accidents in 2003 and 2004 and to compare these values with those of a previous study performed during the period 2000-2001 involving 900 drivers. Blood samples were provided from 2003 under 30-year-old drivers, killed in a traffic accident. Drugs of abuse were determined by gas chromatography-mass spectrometry using the same analytical procedures in all the 12 laboratories. The most frequently observed compounds were by far cannabinoids, that tested positive in 39.6% of the total number of samples. Delta9 tetrahydrocannabinol (THC), the most active of the principle constituents in marijuana (cannabis sativa), was detected in the blood of 28.9% drivers and was the single drug of abuse in 80.2% of the positive cases. It was associated with amphetamines in 7.4% and with opiates and cocaine in 1.9 and 4.8%, respectively. Amphetamines were present in 3.1% of the total number of samples, cocaine metabolites in 3.0% and opiates in 3.5%. When comparing these results with those of a previous study performed 3 years before, a significant increase is observed for THC (28.9% versus 16.9%), cocaine metabolites (3.0% versus 0.2%) and amphetamines (3.1% versus 1.4%). This study demonstrates the critical necessity of implementing in France as soon as possible systematical roadside testing for drugs of abuse. 相似文献
912.
The purpose of this study was to determine the performance characteristics of the Cozart Amphetamine Microplate EIA for detecting amphetamine in oral fluid. Oral fluid samples were collected using the Cozart RapiScan Collection System from 135 volunteer donors from drug treatment clinics. A further 35 oral fluid samples were collected from volunteer donors who were not drug users. The samples were analyzed in the laboratory using the Cozart Amphetamine Microplate EIA and confirmed using gas chromatography-mass spectrometry (GC-MS). The samples were stored frozen until analysis by GC-MS. The intra-assay precision for the Cozart Amphetamine Microplate EIA for amphetamine in oral fluid over forty assays was 2.74-7.1% CV (within assay) and 3.4-7.0% CV (within day). A total of 78 samples were positive for various amphetamines and related designer drugs. The Cozart Amphetamine Microplate EIA, using a cutoff of 45 ng/ml amphetamine equivalents in neat oral fluid, had a sensitivity of 91.7+/-3.3% and a specificity of 95.9+/-1.9% versus GC-MS using a cutoff of 30 ng/ml. A series of potential adulterants of oral fluid were evaluated and shown not to alter the outcome of the test result. 相似文献
913.
Stability of Delta(9)-tetrahydrocannabinol (THC) in oral fluid using the Quantisal collection device
Moore C Vincent M Rana S Coulter C Agrawal A Soares J 《Forensic science international》2006,164(2-3):126-130
This article details the stability of Delta(9)-tetrahydrocannabinol (THC) in oral fluid during collection, extraction and storage. Oral fluid is being increasingly used as the specimen of choice for the detection of drug use in various applications. Studies to determine the extraction efficiency of THC from the collection buffer and stability under various laboratory storage conditions were carried out. THC was extracted from the collection pad and buffer with an average efficiency over 80% and was stable in Quantisal oral fluid extraction buffer when stored at refrigerated temperatures. Fluorescent lighting caused THC losses of over 50%, however the presence of the pad reduced the loss. In the dark, the loss of THC at room temperature was approximately 20% over 14 days. When stored with the serum separators in place, THC losses were significant. After 3 days, THC concentration was reduced by almost 30%, and after 14 days, 60% of the drug was lost and the losses were not concentration dependent. 相似文献
914.
Robinson N Castella V Saudan C Sottas PE Schweizer C Dimo-Simonin N Mangin P Saugy M 《Forensic science international》2006,163(1-2):148-151
The case of seven urine samples collected for anti-doping purposes during a cycling stage race with moderately elevated testosterone and epitestosterone ratio (T/E) is reported. The very low probability of having all seven urine samples with such similar elevated T/E ratio (from 3.2 to 4.7) was very suspicious. Different pattern classification tools were tested to categorize the most similar steroid profiles, but none of the models enabled a clear classification of the different urine samples. Subsequently, genetic profiling of all urine samples was performed and demonstrated that three of the seven samples were collected from the same cyclist. Finally, the International Federation confirmed DNA profiling results. This suggests that urinary steroid data using several methodologies are not appropriate for identification purposes and to an extent not unique to individuals. 相似文献
915.
Jiang B Li Y Wu H He X Li C Li L Tang R Xie Y Mao Y 《Forensic science international》2006,162(1-3):66-73
The human leukocyte antigen (HLA) system is known to be the most complex polymorphic system in the human genome. Among all of the HLA loci, HLA-DRB1 has the second largest number of alleles. The purpose of this study is to develop an oligonucleotide micro-array based HLA-DRB1 typing system for use in forensic identification, anthropology, tissue transplantation, and other genetic research fields. The system was developed by analyzing the HLA-DRB1 (DRB1) genotypes in 1198 unrelated healthy Chinese Han individuals originating from various parts of China and residing in Shanghai, China. METHOD: Polymerase chain reaction (PCR) coupled with the oligonucleotide micro-array technology was used to detect and type HLA-DRB1 alleles of the sample individuals. The reliability, sensitivity, consistency and specificity were evaluated for use in forensic identification. Furthermore, a meta-analysis was carried out by comparing the allele frequencies of the HLA-DRB1 locus with those of other Chinese Han groups, Chinese minorities and other ethnic populations. RESULTS: All the DNA samples yielded a 273 bp amplification product, with no other amplification products in this length range. The minimum quantity of DNA detected by this method is 15 ng in a PCR reaction system of 25 microl. The population studied appeared to be not in Hardy-Weinberg equilibrium. Observed heterozygosity (Ho), expected heterozygosity (He), expected probability of exclusion (PE), polymorphic information content (PIC), and discrimination power (DP) of the HLA-DRB1 locus from the Shanghai Han ethnic group were evaluated to be 0.8022, 0.8870, 0.7741, 0.8771, 0.9750, respectively. A total of 25 HLA-DRB1 alleles were identified. HLA-DRB1*09XX, *04XX, *12XX and *15XX were the most frequent DRB1 alleles, which were observed in 58.76% of the sample. One hundred and sixteen genotypes were found. The five most frequent genotypes were: *04XX/*04XX (0.0626), *09XX/*09XX (0.0593), *04XX/*09XX (0.0551), *09XX/*15XX (0.0384) and *08XX/*12XX (0.0351). The meta-analysis showed that there were uniquely distributed features of DRB1 alleles among various ethnic populations and among the studied population groups from various regions with the same ethnic origin. CONCLUSIONS: An HLA-DRB1 genotyping system has been developed and established based on the oligonucleotide micro-array technology. The HLA-DRB1 typing of the Han population in Shanghai has revealed a relatively high heterogeneity. Information obtained in this study will be useful for medical and forensic applications as well as in anthropology research. Large-scale micro-array detection is highly accurate and reliable for DNA-based HLA-DRB1 genotyping. These results suggest that HLA-DRB1 DNA polymorphisms and the database of the Shanghai Han group have useful applications in processing forensic casework (as personal identification, paternity test), tracing population migration and genetic diagnosis. 相似文献
916.
Causin V Marega C Carresi P Schiavone S Marigo A 《Forensic science international》2006,164(2-3):148-154
Fifty shopping bags, commonly encountered in the packaging of drug doses, were characterized by thickness measurements, infrared spectroscopy and differential scanning calorimetry. By these very straightforward and inexpensive techniques, without sample preparation, nearly all the considered samples could be discriminated. Ninety-seven percent of the possible pairs of white, apparently similar dull polymer films were differentiated. The rather large degree of variability existing in grocery bags, even though they are mass produced, was shown, confirming that these items can be useful in tracing the source of illicit drug doses. 相似文献
917.
苏联专家玛·克依里洛娃曾于本年四月初在上海讲学,这是她的第一次报告.本文是根据当时口译记录下来,整理后送本刊发表的.原文未经报告人核对,如有错误,由记录人负责. 相似文献
918.
鉴定人的意见是苏维埃刑事诉讼中的一种证据,它对揭发犯罪和认定案情有着重大意义.因此,应当向鉴定人的工作和他的意见提出一定的要求,以便保证正确地作出反映真实的结论.这些要求可以表述如下:第一,鉴定人用演绎法进行研究时所引用的作为大前提的原理和材料,应当严格地符合建立在用事实现象检证过的苏维埃科学最新成就的基础上.例如,"犯罪对策学中的同一认定,只能依靠那些已为实践检验过的并且本身是具有科学根据的材料."实践范畴造成我们认识相对性的这种情况,并不排斥作出反映真实结论的可能性.列宁说过:"……不要忘记:实践标准实质上决不能完全地确证或驳倒人的任何表象.这个标准同样是这样地'不确定'以便不致使人底知识变成'绝对',可是同时它又是这样地确定,以便和一切各种各样的唯心论与不可知论进行无情的斗争."第二,在作出鉴定结论时用作小前提的案情,应当在客观上是真实的. 相似文献
919.
920.
根据文莱国家财政官员李约翰的报告说,以文莱在1963年年底的财政状况看来,它是令人兴奋的。这一年财政开支看来不超过5千1百万元(马元,下同),而岁收则约有1亿2千6百万元。财政结余将为国家的贮备金增加到8亿6千6百万元。 由于石油生产量的下降,1964年的岁收将比1963年减少,只有1亿零7百万元。1964年的开支预算估 相似文献