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141.
142.
Induction of hypoxia-inducible factor-1alpha in two kinds of rats asphyxiation death models 总被引:1,自引:0,他引:1
OBJECTIVE: To investigate the expression of hypoxia-inducible factor 1-alpha (HIF1-alpha) in the heart, lung, liver and kidney in rats died of two typical models of asphyxia. METHODS: Two asphyxia models were made and tissue samples of the dead rats were collected from different groups at various postmortem duration. The expression and the changes of HIF1-alpha in various tissues were examined by immunohistochemistry and image analysis techniques. Results Significant expression of HIF1-alpha was observed in the myocardial fibers, kidney cells, liver cells and lung cells in both asphyxia models, but not in the control group. The expression of HIF1-alpha in various tissues in the rat died of nitrogen gas breathing was found in the nuclei at 0 hour and the expression level decreased gradually thereafter. The HIF1-alpha expression level and duration in various tissues of the rat died of hanging were higher and longer than that of the former group, with a peak of the expression level observed 6 hours after death, and then started to decline in all tissues except the heart where the expression still showed an increase 24 hours after death. The control groups showed a steady expression in the cytoplasm but not in the nuclei. CONCLUSION: HIF1-alpha appears to be a valuable biomarker in the diagnosis of asphyxia within 24 hours after death. 相似文献
143.
Brandão RB Martin CC Catirse AB de Castro E Silva M Evison MP Guimarães MA 《Journal of forensic sciences》2007,52(4):913-919
The objective was to investigate color change and surface damage in dental resin composites exposed to high temperatures over different time intervals for comparative purposes. Samples were prepared using two resins - Z100(R) (R1) and Charisma (R2), heated at the following temperatures: 200 degrees C, 400 degrees C, 600 degrees C, 1000 degrees C, for 15, 30 and 45 min (n = 104 for each resin sample). Color (DeltaE) and brightness (DeltaL) changes were analyzed by spectrophotometry using the CIE Lab system and surface changes by Scanning Electron Microscopy (SEM). R1 showed more intense color changes after heat exposure than R2. DeltaL values were found to be the best parameter for evaluation of light and color change. A biphasic pattern after thermal exposure was detected, from dark brown to light white. SEM showed more intense alterations in R2 than in R1. These results indicate that the parameters observed in both resins are useful as a guide in forensic analyses. 相似文献
144.
Fanton L Bévalot F Schoendorff P Lalliard S Jdeed K Malicier D 《The American journal of forensic medicine and pathology》2007,28(3):262-266
A prospective study of 161 victims of falls from height is reported. The aim was to determine the interest of systematic qualitative and quantitative toxicological analysis in such fatalities. The primary cause of death was suicide (84.5%), followed by accidents (7%) and homicide (1%). In the remaining 7.5%, cause of death was undetermined. In the suicides, there was evidence of psychotropic medicines in 57% of the observations, with a much higher proportion of benzodiazepines and antidepressants in women than in men. Quantitative toxicologic analysis showed overdosing on medication in 16 suicide victims, with toxic levels in 11 of these. Systematic qualitative and quantitative toxicologic analysis made a significant contribution to the diagnosis of suicide by revealing either an unknown psychiatric treatment or a toxic level. 相似文献
145.
本文从主体间性角度出发,论述了被追诉人主体性的内向性和外向性,提出了内向性的两个价值向度:人格尊严、意志自由之选择机能;外向性的两个价值向度:主体性意义上的平等、维权与自卫,在此基础上论述了被追诉人主体性权利构成的元权利、程序生成性权利概念,阐述了被追诉人元权利构成:无罪推定权、程序参与及选择权、平等对抗权和辩护权,建构了元权利与程序生成性权利的矩阵关系,并进而分析了元权利的相互关系以及各元权利所蕴涵的主体性价值。 相似文献
146.
147.
A total of 743 lethal outcomes of thromboembolytic complications of trauma, diseases and certain pathological conditions as observed in 1999-2001 and in the three quarters of 2002 were studied. The undertaken analysis confirmed two factors provoking the pathological thrombosis, i.e. 1. Pathological changes observed in the surface vascular wall preconditioned by mechanical damages, atherosclerotic process and aging; and 2. A slower blood flow due to an impaired blood circulation, a forced positioning and to hypodynamics. While deciding on a possibility of a direct cause-effect relation between past traumas, surgeries, poisonings and death of thromboembolism of the pulmonary arteries (TEPA), such relation can be mentioned only on rare occasions. It is more often the case that an indirect, mediated relationship is found, when TERA evolves due to an unfavorable combination of risk factors, i.e. a forced immobility, changing coagulated blood system, impaired blood vessels etc. 相似文献
148.
Allele frequency data and forensic efficiency parameters for 10 STR loci: D3S1358, vWA, D16S539, D2S1338, D8S1179, D21S11, D18S51, D19S433, TH01 and FGA, were estimated from a sample of 207 unrelated individuals in Lodz region of Poland. 相似文献
149.
150.
Reis EL Sarkis JE Neto ON Rodrigues C Kakazu MH Viebig S 《Journal of forensic sciences》2003,48(6):1269-1274
This work presents a novel collection method for gunshot residues (GSR) using a sampling procedure based on ethylenediaminetetraacetic acid (EDTA) solution as a complexing agent on moistened swabs. Detection was via a sector-field inductively coupled plasma mass spectrometry (HRICP-MS). The proposed collection and analytical method allowed detection of antimony (Sb), barium (Ba) and lead (Pb) after .38 shot tests. at detection limits of less than 1 microg L(-1) in four different areas of the hands of volunteers. This paper includes a discussion concerning hand areas near the thumb and forefinger as being more suitable for GSR collection as well as a comparison between differences observed using 2% diluted EDTA. 2% nitric acid solution, and simple deionized water as collecting solutions, proving the superior efficiency of EDTA in GSR recoveries. 相似文献