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901.
Brunet B Doucet C Venisse N Hauet T Hébrard W Papet Y Mauco G Mura P 《Forensic science international》2006,161(2-3):169-174
This study presents a new animal model, the Large White Pig, which was tested for studying cannabinoids metabolism. The first step has focused on determination of plasma kinetics after injection of Delta(9)-tetrahydrocannabinol (THC) at different dosages. Seven pigs received THC by intravenous injections (50, 100 or 200 microg/kg). Plasma samples were collected during 48 h. Determination of cannabinoids concentrations were performed by gas chromatography/mass spectrometry. Results showed that plasma kinetics were comparable to those reported in humans. Terminal half-life of elimination was 10.6 h and a volume of distribution of 32 l/kg was calculated. In a second step, this model was used to determine the kinetic profile of cannabinoids distribution in tissues. Eight Large White male pigs received an injection of THC (200 microg/kg). Two pigs were sacrificed 30 min after injection, two others after 2, 6 and 24 h. Different tissues were sampled: liver, kidney, heart, lung, spleen, muscle, fat, bile, blood, vitreous humor and several brain areas. The fastest THC elimination was noted in liver tissue, where it was completely eliminated in 6 h. THC concentrations decreased in brain tissue slower than in blood. The slowest THC elimination was observed for fat tissue, where the molecule was still present at significant concentrations 24 h later. After 30 min, THC concentration in different brain areas was highest in the cerebellum and lowest in the medulla oblongata. THC elimination kinetics noted in kidney, heart, spleen, muscle and lung were comparable with those observed in blood. 11-Hydroxy-THC was only found at high levels in liver. THC-COOH was less than 5 ng/g in most tissues, except in bile, where it increased for 24 h following THC injection. This study confirms, even after a unique administration, the prolonged retention of THC in brain and particularly in fat, which could be at the origin of different phenomena observed for heavy users such as prolonged detection of THC-COOH in urine or cannabis-related flashbacks. Moreover, these results support the interest for this animal model, which could be used in further studies of distribution of cannabinoids in tissues. 相似文献
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Hammer MF Chamberlain VF Kearney VF Stover D Zhang G Karafet T Walsh B Redd AJ 《Forensic science international》2006,164(1):45-55
A set of 61 Y chromosome single-nucleotide-polymorphisms (Y-SNPs) is typed in a sample of 2517 individuals from 38 populations to infer the geographic origins of Y chromosomes in the United States and to test for paternal admixture among African-, European-, Hispanic-, Asian-, and Native-Americans. All of the samples were previously typed with the 11 core U.S. Y chromosome short tandem repeats (Y-STRs) recommended by SWGDAM, which revealed high levels of among ethnic group variation and low levels of among-population-within-ethnic-group variation. Admixture estimates vary greatly among populations and ethnic groups. The frequencies of non-European (3.4%) and non-Asian (4.5%) Y chromosomes are generally low in European-American and Asian-American populations, respectively. The frequencies of European Y chromosomes in Native-American populations range widely (i.e., 7-89%) and follow a West to East gradient, whereas they are relatively consistent in African-American populations (26.4+/-8.9%) from different locations. The European (77.8+/-9.3%) and Native-American (13.7+/-7.4%) components of the Hispanic paternal gene pool are also relatively constant among geographic regions; however, the African contribution is much higher in the Northeast (10.5+/-6.4%) than in the Southwest (1.5+/-0.9%) or Midwest (0%). To test for the effects of inter-ethnic admixture on the structure of Y-STR diversity in the U.S., we perform subtraction analyses in which Y chromosomes inferred to be admixed by Y-SNP analysis are removed from the database and pairwise population differentiation tests are implemented on the remaining Y-STR haplotypes. Results show that low levels of heterogeneity previously observed between pairs of Hispanic-American populations disappear when African-derived chromosomes are removed from the analysis. This is not the case for an unusual sample of European-Americans from New York City when its African-derived chromosomes are removed, or for Native-American populations when European-derived chromosomes are removed. We infer that both inter-ethnic admixture and population structure in ancestral source populations may contribute to fine scale Y-STR heterogeneity within U.S. ethnic groups. 相似文献
903.
目的探索毛发中外源性GHB的检测及判断的可行性,为涉GHB的鉴定提供方法和依据。方法建立毛发中GHB的GC/MS分析方法,并通过动物实验,考察毛发中内源性GHB的质量分数范围、外源性GHB在毛发中的时间过程以及给药剂量、毛发颜色与毛发中GHB的质量分数关系。结果豚鼠和中国人黑色毛发中内源性GHB质量分数分别为(3.01±1.41)ng/mg(n=28)和(1.02±0.27)ng/mg(n=20);摄GHB后毛发中GHB质量分数明显增加且与给药剂量呈正相关性;GHB在毛干中呈窄带分布;深色毛发中GHB质量分数高于浅色毛发。结论毛发中GHB的检测适用于GHB滥用和中毒的法医毒物学鉴定;根据毛发中的GHB质量分数和毛发分段分析可判断GHB的来源。 相似文献
904.
目的探讨车祸致胸、腰椎损伤程度与伤残程度的关系,总结伤残评定经验,探寻其规律性。方法选择胸、腰椎损伤的鉴定447例,重新审查诊断,分析治疗措施,评价胸腰部活动度丧失程度及神经功能障碍情况,分析损伤程度与后遗障碍之间的关系,综合评定伤残。结果胸、腰椎损伤类型及数量并不决定其胸、腰部活动障碍程度及神经损伤后遗症严重程度;椎体损伤的部位与胸腰部活动度障碍关系密切;神经损伤主要集中在T1至L2段脊柱损伤;椎体损伤医院误诊率较高。结论伤残评定应分析损伤与后遗症严重程度的因果关系,以损伤所致后遗症为评残依据,重点关注脊柱功能的丧失程度。 相似文献
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910.
Tournel G Bécart-Robert A Courtin P Hédouin V Gosset D 《Journal of forensic sciences》2006,51(5):1166-1168
ABSTRACT: A 25-year-old woman being treated for non-Hodgkin's lymphoma was accidentally given vindesine intrathecally. The error was recognized immediately and a spinal cord washing was performed through syringing with isotonic saline. However, the patient died 6 weeks later with increasing paralysis, which was followed by neurologic failure. The deceased was autopsied and the central nervous system was removed for a microscopic examination. The results showed microscopic lesions extending from the lumbar to the thoracic portion of the spinal cord, which included pseudocystic transformation of the cells, degeneration of myelin, and microhemorrhages. The brain was edematous and, in the cerebellum, the vermis showed a loss of granule and Purkinje cells. The authors compare this report on vindesine toxicity with cases in the literature involving vincristine. The treating physician admitted responsibility and was sentenced to both a fine and imprisonment. 相似文献