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991.
To improve the possibilities to delimit the time of death after longer laytime it was examined if this is possible by immunohistochemical detection of thyroglobulin. The results show that in our examination material the colloid and the follicular cells of the thyroid glands of up to 5-day-old corpses produce a positive immunoreaction towards thyroglobulin in all cases whereas none of the corpses older than 13 days show such a reaction. This means that in case of a negative immunoreaction the time of death can be assumed to lie more than 6 days before the autopsy. The fact that a negative immunoreaction occurs consistently after 13 days leads to the conclusion that when thyroglobulin has been stained in a specimen, the death of the respective person must lie a maximum of 12 days earlier, whereby these time-limits may change in considerably different surrounding conditions.  相似文献   
992.
To develop a method of detecting methadone in the human brain by immunohistochemistry, brain tissue of frontal cortex, cerebellum, hippocampus, basal ganglions and brain stem from victims of a lethal methadone overdose was examined. The staining was performed with a monoclonal anti-methadone antibody from the mouse, originally developed for immunochemichal purposes (ELISA). With the help of the DAKO((R)) Catalyzed Signal Amplification (CSA) System, a specific positive immunoreaction was obtained in the neurons of the frontal cortex and hippocampus, as compared with specimen from deaths without exposition to methadone. Thus, along with metamphetamine, phenobarbital, morphine and insulin, immunohistochemical detection is also possible for methadone and the intake of this medicament can now be proven morphologically.  相似文献   
993.
Toluene, an abused substance in Japan, is a neurotoxic chemical that has been shown to have neurobehavioral and electrophysiological effects. In previous work, both acute and chronic effects of toluene on cells have been studied extensively. However, although glial cells are thought to play an important role in the survival of neurons in the brain, the effect of toluene on glial cell function has not yet been characterized. To elucidate this, the effect of toluene inhalation on astrocytes in rat brain was examined. Toluene exposure (1500 ppm for 4 h on 4-10 days) augmented glial fibrillary acidic protein (GFAP) immunoreactivity, particularly in the hippocampus and cerebellum. Quantitative analysis showed that toluene inhalation markedly enhanced GFAP expression in the hippocampus and cerebellum. In both regions, proliferating cell nuclear antigen (PCNA) showed no obvious changes, but glutamine synthetase (GS)-immunoreactive cells were markedly increased by toluene exposure. Thus, the elevation of GFAP expression was induced by astrocyte activation rather than by cell proliferation. If toluene exposure activates astrocytes, astrocytes may play a role in the neurophysiological changes observed in toluene intoxication. A neurotrophic factor, basic fibroblast growth factor (b-FGF) was observed immunohistochemically in the capillary vessel walls in the hippocampus and the cerebellum of toluene-intoxicated rats. Basic-FGF may have induced GFAP expression both in the hippocampus and the cerebellum. So, other neurotrophic factors may affect the difference of GFAP elevation between the hippocampus and the cerebellum. These differences may relate to neurobehavioral function of each brain part after toluene exposure.  相似文献   
994.
By means of the new method of Streifenlichttopometrie (SLT) it is possible to record the complete body surface of casualties in a practically photorealistic fashion, i.e. three-dimensionally and in colour. In comparison with the classic method of Photogrammetry Streifenlichttopometrie (SLT) is remarkably faster (10,000 points/s instead of 1 point/s) and in addition the colour of every point measured upon the corpse's surface is instantly recorded. Taking into consideration the resolution required and the qualities of the camera system the body surface is recorded in 'patches', i.e., areas of a defined extension (in the present case 500 mmx500 mmx200 mm) which are marked with a body fixed reference frame to grant the exact matching of the data after the recording process. Length, perimeter, square and volume of the body segments and injuries can be determined. Furthermore the natural colour of the wounds can be used for an immediate classification according to the intensity of the impact forces. In addition the 3-D coordinates of the body surface including the wounds can be transferred into an animated computer simulation for the reconstruction of the traumatic events.  相似文献   
995.
In animal experiment and in cell culture, chronic morphine treatment has been followed by a reduction as well as an increase of the delta-opioid receptor (OR) number. The present postmortem morphometric study of morphine-related fatalities of drug addicts (n=12, 22-35 years old, with blood unconjugated morphine levels from 27.1 to 407 ng/ml, m.v. 176.9 ng/ml) versus a non-addicted control group (n=13, 10-44 years old) is intended to examine whether chronic opiate exposure also affects the numerical density of deltaOR expressing neurons in the human neocortex (area 10 according to Brodmann (Vergleichende Lokalisationslehre der Grosshirnrinde (1909) Johann Ambrosius Barth, Leipzig)). For the immunohistochemical procedure, vibratome sections (100 microm) were incubated with a monoclonal antibody against the deltaOR diluted 1:100, and immunoreactive sites were visualized using an immunoperoxidase protocol. The numerical densities of OR expressing and Nissl-stained neurons were assessed morphometrically (camera lucida drawings). In both collectives, the anti deltaOR immunoreactivity was predominantly localized in pyramidal neurons of layers (L) II/III and V as well as in round and ovoid neurons of L VI. In the drug-related fatalities, the density of neurons expressing deltaOR protein amounted for 2515+/-240/mm(3), in the control group for 2616+/-204/mm(3), thus displaying no statistically significant difference. These findings go along with the binding behavior of opioid ligands in postmortem brains of heroin addicts revealing similar receptor densities and affinities in the control subjects and addicts.  相似文献   
996.
A number of DNA polymorphisms have been found to be associated with the pathophysiology of some common disease. If the LDLR polymorphism is directly or indirectly related to some fatal disease, the distribution of the polymorphism may vary with age. We therefore investigated the aging-associated distribution of the LDLR polymorphism. Blood samples were collected from Japanese cadavers (aged 0-91) at autopsy. The LDLR polymorphism was detected using a AmpliType PM PCR Typing kit. When the LDLR genotype was examined in cadavers divided according to age into 0-29 year group, 30-59 year group, and 60-91 year group, there were significant differences in genotype among the three age groups and between the 0-29 year group and 60-91 year group. The LDLR-A genotype tended to be lower in the older cadavers. The present study revealed that there were aging-dependent differences in the distribution of the LDLR polymorphism in autopsy samples, suggesting that a common mutation involved in the occurrence of fatal diseases may be present near the LDLR-A polymorphism locus.  相似文献   
997.
The binding of charged substances from external aqueous media to hair has been investigated through the use of fluorescence microscopy. Eleven hair samples, reflecting various ethnic groups and cosmetic treatments, were tested. Rhodamine 6G, a cationic dye representative of drugs such as cocaine and opiates, showed incorporation throughout the hair of all samples except one. In contrast, fluorescein, an anionic dye representative of drugs such as THC carboxylic acid, was not readily incorporated. The incorporation of rhodamine 6G was faster for chemically 'straightened' and bleached African-American female hair than for untreated hair. Incorporation of rhodamine 6G followed a pH dependence, but an ionic strength dependence could not be established. These studies support three postulates: (1) electrostatic interactions explain the preferential binding of cationic drugs of abuse to hair; (2) the hair matrix, or the non-helical portion of hair, is accessible to external solutions and thus subject to contamination; and (3) cosmetic treatments may alter the helical portion of hair thereby increasing its accessibility to external contamination.  相似文献   
998.
Household survey data on age at first use of alcohol, tobacco, marijuana,and hard drugs can be biased due to sample selection and inaccuraterecall. One potential concern is attrition, whereby individuals who getinvolved with substance use at an early age become increasingly less likelyto be surveyed in successive years. A comparison of data from the NationalHousehold Survey on Drug Abuse (NHSDA) with data from a longitudinal studysuggested that attrition might have caused substantially less bias thandid forward telescoping, the inflating of age at first useover time. The evidence of forward telescoping was particularly pronouncedwith respect to age at first use of alcohol. This paper presents a procedurefor correcting the distribution of age at first use for forward telescoping(but not attrition) by viewing a portion of the NHSDA data collected insuccessive years as constituting a cohort study. Results are presented fromapplying this procedure with NHSDA data collected from 1982 to 1995 forrespondents born 1968–1973. The findings suggest that preventionprograms need to be introduced at an earlier age than would be indicatedby uncorrected retrospective data. Other implications are alsohighlighted.  相似文献   
999.
同一个体发毛角蛋白电泳谱型的分析   总被引:3,自引:1,他引:2  
Yan PH  Fang JX  Jin JF 《法医学杂志》2000,16(2):79-80
用SDS -PAGGE对收集到的 2 0例人体表毛发 (头发、阴毛、腋毛、腿毛 )角蛋白组分进行了分析。结果表明 ,同一个体毛发角蛋白电泳谱型基本相同 ,用激光光密度仪对电泳凝胶板扫描后证实 ,同一个体毛发角蛋白组分相对百分含量也无明显差异 ;人头部不同部位 (顶部、左侧、右侧、额部、枕部 )头发角蛋白的电泳谱型和角蛋白组分相对百分含量也基本相同。同一个体毛发角蛋白组分的分析 ,可为法医物证学鉴定中的毛发个人识别提供重要的依据。  相似文献   
1000.
The study consisted of two parts. First, a new scale of interpersonal trust for adolescents was constructed using a representative sample of 70 students from a community high school. Second, the hypothesis was tested that disaffected youth compared to the more conventional would show less interpersonal trust. Two matched groups of 57 students each were employed for the second part of the study. Results indicate that the new scale is a reliable and valid measure. Correlates of the scale disclose that trust is associated with interpersonal distance, certain developmental factors, and the quality of parent-adolescent relations. Results from the second part of the study tend to confirm the hypothesis in that greater trust scores were found among students with more conventional beliefs.This study was partly supported by NIMH Grant No. MH9210, Ford Foundation Grant No. 69-0264B, and the Jessie and C. Clement Stone Foundation.Received his Ph.D. from the University of Kansas. Currently working on personality and clinical problems of adolescents and adults.Recieved his Ph.D. from the University of Michigan. Plans to continue his work of program development in the area of affect education in secondary schools.Received his Ph.D. from Harvard University. Current work is in the area of community mental health.  相似文献   
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