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931.
Gaulier JM Tonnay V Faict T Sayer H Marquet P Lachâtre G 《Journal of forensic sciences》2003,48(4):880-882
Through a case report, the authors illustrate the volatile substance abuse (VSA) toxicological investigation difficulties mainly due to evaporation of the compounds from postmortem samples and to the lack of reference data for interpretation. A 17-year-old man, student in a chemistry institute, was found dead with a plastic bag placed over his head. Several chemical substances were found in his belongings. Autopsy findings included serious pulmonary lesions and hemorrhagic digestive ulcerations. A large screening of drugs and toxic compounds and selective analyses for several classes of drugs of abuse were carried out in the autopsy samples. In particular, a headspace (HS), -gas chromatography/-mass spectrometry (GC/MS) technique was used to screen for volatile substances and metabolites in the biological samples and for residues of volatile substances on the surface of the plastic bag and in the chemicals found on the scene. The main analytical finding was the presence of alkanes (heptane, methyl-2-pentane, methyl-3-hexane, methylcyclohexane) in the gastric content. The literature data, VSA practices, long time-delay between death and autopsy, preservation conditions of the biological samples before analysis, and in-lab experiments on evaporation of volatile substances were considered to interpret this result. The present fatality was attributed to VSA with a gasoline-based stain remover like "eau écarlate," associated with a hypoxic recreation practice using a plastic bag. 相似文献
932.
Kapustin AV Zombkovskaia LS Panfilenko OA Serebriakova VG 《Sudebno-meditsinskaia ekspertiza》2003,46(6):25-28
Two variants of thanatogenesis were formulated in cases of death of acute alcohol intoxication; according to the above variants, different combinations of macro- and micro signs as well as of biochemical indices of carbohydrates content in the hepatic tissues and blood are revealed during cadaver examinations. The diagnostic value of the mentioned signs demands that the thanatogenesis specific features must be taken into account in each separate case. 相似文献
933.
Laboratory schemes related with the procedure of purifying the osseous and dental samples by applying the dental drilling machine, dental technical carborundum shapes, fogging discs and hard-alloy dental drills were made use of to improve the quality and effectiveness of the mentioned schemes used prior to molecular-and-genetic expertise tests. 相似文献
934.
The short tandem repeat allelic profiles at to 15 autosomal polymorphic loci were analyzed in four tribal populations of Mizoram (India). The analysis was performed on 354 unrelated healthy individuals belonging to Mongoloid races. All the samples were subjected to sex test (Amelogenin marker) besides the STR typing and in all instances; it has shown no deviation from expectation. The allele frequencies for all the analyzed loci in the studied populations are within expected range in comparison to the populations from same racial background. No significant deviation from the Hardy-Weinberg Equilibrium was observed for all the populations. In no cases the observed heterozygosity is less than that of expected values and it varied from 0.978 (Penta E) to as low as 0.425 (THO1). The discriminatory power and exclusion probability values for all the analyzed markers are significantly high and thus reveal high forensic significance. There is no evidence for association of alleles among the 15 studied loci. This allele frequency data will be useful for human identity testing in Mizo population. 相似文献
935.
Brandt-Casadevall C Ben Dhiab M Taroni F Castella V Dimo-Simonin N Zemni M Mangin P 《Forensic science international》2003,135(3):247-250
Alleles and haplotypes frequencies for 10 Y-chromosome STR loci (DYS19, DYS385 I/II, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS438 and DYS439), included in the Y-Plex6 and Y-Plex5 kits were determined for a Tunisian population sample of 100 male individuals. 相似文献
936.
The present study reexamines the accuracy of the supero-inferior femoral neck diameter for the determination of sex using a modern sample of French individuals. In 1998, Seidemann et al. used this univariate method for sex determination with the Hamann-Todd collection. Stojanowski and Seidemann in 1999 tested previous results on a modern sample taken from the University of New Mexico and concluded that the Caucasian male samples exhibited no significant differences between individuals born before and after 1900, but the Caucasian female subgroup did exhibit differences with an increase of the SID in the modern sample. The current study compares the previous results of the supero-inferior femoral neck diameter with a modern sample of elderly French individuals born after 1910. Both sides of the femur were measured. No statistical difference was found between the right and left side (p = 0.31). The results showed a significant difference between the pre-1900 and the modern sample, with an increase in femoral neck diameter in modern populations. The comparison of the SID values between the two modern samples (Mexico and Nice) showed no significant differences in the femoral neck diameter in the two male subgroups (p = 0.05), but the measurements of the SID in the female subgroup did exhibit significant differences with an increase of the neck femoral diameter (p < 0.01) in the modern French population. These results demonstrate an increase in the neck femoral morphology in the elderly European French females samples. 相似文献
937.
938.
939.
940.
Preliminary research using on-line supercritical fluid extraction/gas chromatography-mass spectrometry (SFE/GC-MS) has shown that the natural and artificial surface components of human scalp hair are reproducible and differentiable. Therefore, these components may be useful for individualization or determining demographic characteristics or both. However, it is not known how the efficiency and selectivity of on-line SFE/GC-MS compares to other extraction methods. In this study, ultrasound, Soxhlet, and pressurized-fluid extraction were used to extract 1 mg to 1.3 g portions of a composite hair sample taken from an Asian male between the ages of 10 and 18. Percent extractables ranged from 0.9% to 5.6%, depending on the solvent used, and tended to increase with solvent polarity. Chemical analysis using GC/MS showed that the extracts contained large proportions of free fatty acids, squalene, cholesterol, and various wax esters. Finally, comparisons to SFE/GC-MS showed that this method possesses adequate efficiency, no observable differences in selectivity, and greater potential for miniaturization. 相似文献