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371.
Use of PCR-RFLP for differentiation of calliphorid larvae (Diptera,Calliphoridae) on human corpses 总被引:2,自引:0,他引:2
Schroeder H Klotzbach H Elias S Augustin C Pueschel K 《Forensic science international》2003,132(1):76-81
Blowfly larvae found on human corpses are important for the estimation of the postmortem interval (PMI) and other questions of forensic relevance. Some of these species are difficult to differentiate morphologically, therefore a molecular method was elaborated for species identification. Specific fragments of the COI and COII region of the mitochondrial DNA (mtDNA) were amplified followed by digestion with different restriction enzymes. Using a 1.3 kb fragment, identification of Lucilia sericata, Calliphora vicina and Calliphora vomitoria was possible by digestion with only one restriction enzyme using either DraI or HinfI. Furthermore, we sequenced 349 bp (a part of the COI and COII regions) from the same three species and found 34 nucleotide distinctions between C. vicina and L. sericata, 30 between C. vomitoria and L. sericata and 15 between the two Calliphora species. These results aid in quick identification of species used for estimation of PMI. 相似文献
372.
Yoshida K Mizuno N Fujii K Senju H Sekiguchi K Kasai K Sato H 《Forensic science international》2003,132(2):166-167
Allele frequencies for nine short tandem repeats (STR) loci: D3S1358, vWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317 and D7S820 were determined in a Japanese population using the AmpFlSTR Profiler PCR amplification kit (Applied biosystems). 相似文献
373.
The extraction of impurities from illegally produced 3,4-methylenedioxymethamphetamine (MDMA) has been studied in order to optimize the parameters. Two different MDMA samples were used. Particular attention was paid to the influence of the pH, the evaporation step, and the sample storage. The method used was an extraction of impurities by diethyl ether from a buffer solution at pH 11.5, followed by gas chromatography (GC) mass spectrometric (MS) analyses after a dryness concentration under monitored conditions of the ethereal extract. Repeat extractions of the same sample gave an average relative standard deviation (RSD) of less than 8.5% within day and less than 10.5% between days. 相似文献
374.
We compared the lungs of six drowned and six non-drowned persons over 70 to determine whether there is evidence of acute overinflation in drowning that can be distinguished from senile lung emphysema. All left lungs underwent intrathoracic formalin fixation to preserve their state of insufflation. To assess the effects of lung collapse, all right lungs were sectioned as usual and then immersed in formalin. After histological processing, microphotography and image processing of 12 specimens per corpse, 50 binary images of each specimen were measured by computerized morphometry. Intrathoracic fixation resulted in significantly less tissue area (and more airspace) in the left than in the right lungs of both groups. Comparing both groups' left lungs revealed that the interalveolar septa were thinner and the area occupied by connecting nodes smaller in drowning; these single nodes also tended to be smaller. There was a tendency for less alveolar tissue area per image in drowning than in control lungs and for narrow tissue structures to comprise a higher percentage of both the total tissue area and total tissue perimeter per image. We conclude that there is morphological evidence of acute overinflation even in senile lungs, but this is masked by postmortem lung collapse as suggested by the overlapping values of the right lungs. Support to the diagnosis of drowning among drowned elderly patients can only be available in lungs subjected to intrathoracic postmortem fixation. 相似文献
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The first large-scale human trial of an HIV vaccine produces disappointing results overall, but finds that the vaccine may have been effective among some of the minority populations participating in the trial. Whatever the significance of this finding (the debate continues), there was a consensus: (a) that the trial provided very useful information on how to conduct large-scale HIV vaccine trials; (b) that further research needs to be conducted; (c) that governments need to contribute more to vaccine research and development; and (d) that existing prevention efforts must be maintained or expanded. 相似文献
379.
Canada's first ministers have signed a health accord that could potentially lead to significant changes to Canada's health-care system. But the agreement is short on details and the new initiatives may not keep pace with the expectations of Canadians. 相似文献
380.