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981.
Gunshot wounds of skin and long cortical bones inflicted by the special intelligence knife (NRS and NRS-2: special silent cartridges SP-3 and SP-4) from different distances were examined. Stereomicroscopy, emission spectral analysis, contact-diffusion method and regression- step-by-step analysis were made use of within the case study. A lack of mechanical, thermal or chemical impact from firing gas and of fire soot as well as presence of particles of rubber, copper and sealing varnish, i.e. the most informative shot products, were found to be the main distinctive features in the said wounds. The data obtained can be used in the differential diagnosis of a type and model of the used gun. 相似文献
982.
Denisova VV 《Sudebno-meditsinskaia ekspertiza》2004,47(6):36
The subject of the case study was blood of 8 fish species. It was examined within the ABO system. 68 tests of stains of fish blood mixed with human blood were made. It was shown as possible to differentiate between human blood and fish blood in mixed stains. 相似文献
983.
Issues related with the material-and-technical outfit of state forensic medical bureaus of Russia's defense ministry are under discussion. The present-day condition of their instrumentation degree is described; methods are suggested of how to build up the material-and-technical base by using the limiting form system with the "conclusive medicine" principles. 相似文献
984.
A comprehensive series of experiments was undertaken to find the reasons why the cigar-butt stuff, removed from accident places for investigation at forensic-biological laboratories, affects different sera. A number of such reasons were established. Methods are suggested to eliminate the cigar-butt impact with the aim of ensuring the most accurate results while determining the group adherence of saliva on the cigar-butts. 相似文献
985.
986.
Previously, we have developed different variants, for the expert use, of information technologies, i.e. of computer automated analytical systems, to ensure an effective analysis of huge bulwarks of molecular-genetic expert findings. The results obtained in the above research significantly advanced the possibilities of expert evaluation related with personality identification under the conditions of a big death toll; they also cleaned the ground for the introduction of such methodological approaches in the practice of investigations of emergency accidents involving huge death tolls. Described within the present case study is a practical experience of forensic medical identification of unrecognized remains in air crashes with huge human death tolls implemented through computer-assisted complex molecular-genetic tests on the basis of indirect DNA identification involving the establishment of blood relationship. 相似文献
987.
988.
989.
Yegles M Labarthe A Auwärter V Hartwig S Vater H Wennig R Pragst F 《Forensic science international》2004,145(2-3):167-173
In previous investigations hair analysis for ethyl glucuronide (EtG) and fatty acid ethyl esters (FAEE) proved to be suitable for the detection of excessive alcohol consumption. The aim of this study was to compare EtG and FAEE concentrations in hair of alcoholics, social drinkers and teetotallers. Hair samples from 10 alcoholics in withdrawal treatment, 11 fatalities with documented excessive alcohol consumption, four moderate social drinkers who consumed up to 20 g ethanol per day, and three strict teetotallers were analysed. After external degreasing with n-heptane, extraction with a dimethyl sulfoxide/n-heptane mixture and headspace solid-phase microextraction of the extracts, four fatty acid ethyl esters (FAEEs) (ethyl myristate, ethyl palmitate, ethyl oleate and ethyl stearate) were analysed by gas chromatography-mass spectrometry (GC-MS) with deuterated internal standards. EtG was determined by GC-MS/NCI after ultrasonication of the samples with H2O, cleanup by SPE with aminopropyl columns and PFP derivatisation. The following concentrations were measured for the four groups: teetotallers EtG < 0.002 ng/mg, FAEE 0.05-0.37 ng/mg, moderate social drinkers EtG < 0.002 ng/mg, FAEE 0.26-0.50 ng/mg, alcoholic patients EtG 0.030-0.415 ng/mg, FAEE 0.65-20.50 ng/mg and the fatalities with alcohol history EtG 0.072-3.380 ng/mg, FAEE 1.30-30.60 ng/mg. The results confirm that by using a cut-off value of the sum of FAEE > 1 ng/mg and/or a positive EtG result in hair, excessive alcohol consumption can be identified using hair analysis. However, no significant correlation between the EtG and FAEE concentrations in the positive cases could be shown. Segmental analysis of some of the specimens did not reveal the same distribution for EtG compared to FAEE in hair, and no chronological accordance compared to the self-reported alcohol consumption could be observed for both parameters. These different results of both methods are discussed in terms of differences between EtG and FAEE in mechanism of formation and incorporation into hair and elimination from hair. 相似文献
990.
Cawley AT Hine ER Trout GJ George AV Kazlauskas R 《Forensic science international》2004,143(2-3):103-114
A simple means of detecting the abuse of steroids that also occur naturally is a problem facing doping control laboratories. Specific markers are required to allow the detection of the administration of these steroids. These markers are commonly measured using a set of data obtained from the screening of samples by gas chromatography-mass spectrometry (GC-MS). Doping control laboratories further need to confirm identified abuse using techniques such as gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). An interesting urinary species was found while following the pharmacokinetics and changes to the steroid profile from single and multiple oral doses of the International Olympic Committee/World Anti Doping Agency (IOC/WADA) prohibited substance, dehydroepiandrosterone (DHEA). The urine samples collected from the administration studies were subject to GC-MS and GC-C-IRMS steroid analysis following cleanup by solid phase extraction techniques. A useful urinary product of DHEA administration was detected in the urine samples from each of the administration studies and was identified by GC-MS experiments to be 3alpha,5-cyclo-5alpha-androstan-6beta-ol-17-one (3alpha,5-cyclo). This compound occurs naturally but the concentrations of 3alpha,5-cyclo were elevated following both the single DHEA administration (up to 385 ng/mL) and multiple DHEA administrations (up to 1240 ng/mL), in relation to those observed prior to these administrations (70 and 80 ng/mL, respectively). A reference distribution of urine samples collected from elite athletes (n = 632) enabled the natural concentration range of 3alpha,5-cyclo to be established (0-280 ng/mL), with a mean concentration of 22 ng/mL. Based on this an upper 3alpha,5-cyclo concentration limit of 140 ng/mL is proposed as a GC-MS screening marker of DHEA abuse in athletes. GC-C-IRMS analysis revealed significant 13C depletion of 3alpha,5-cyclo following DHEA administration. In the single administration study, the delta13C value of 3alpha,5-cyclo changed from -24.3 per thousand to a minimum value of -31.1 per thousand at 9 h post-administration, before returning to its original value after 48 h. The multiple administration study had a minimum delta13C 3alpha,5-cyclo of -33.9 per thousand during the administration phase in contrast to the initial value of -24.2 per thousand. Preliminary studies have shown 3alpha,5-cyclo to most likely be produced from DHEA sulfate found at high levels in urine. The complementary use of GC-MS and GC-C-IRMS to identify new markers of steroid abuse and the application of screening criteria incorporating such markers could also be adapted by doping control laboratories to detect metabolites of androstenedione, testosterone and dihydrotestosterone abuse. 相似文献