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991.
992.
The aim of this study was to reveal histopathological features for differential diagnosis of skin lesions caused by electrocution, flames and abrasions. Based on the causes of the lesions, cases were assigned into three groups. Group 1 included 30 deaths from electric shock. Group 2 included 30 individuals with flame burns who died in the fires. Group 3 included 30 deaths from traffic accidents, from which the individuals had abrasions. Data from the crime scene investigations and macroscopic and microscopic findings from the autopsies allowed determination of the cause of death in all cases. The features of the lesions examined under the light microscope were intraepidermal separation, subepidermal (dermoepidermal) separation, coagulation necrosis in the epidermis, nuclear elongation in the epidermis, dark-staining epidermal nucleus, depth of homogenization in the dermis, and nuclear elongation in the epithelium of hair follicles. A significantly high rate of electrical lesions had intraepidermal separation. The rate of subepidermal separation was slightly more significant in flame burns. A significantly higher rate of electrical lesions had both intraepidermal and subepidermal separation. The rate of coagulation necrosis in the epidermis was significantly the highest in electrical lesions. Although the severity of nuclear elongation was the most significant in electrical lesions, varying degrees of nuclear elongation in the epidermis were present in all three groups. Dark staining of the epidermal nuclei was present in all lesions except for one electrical lesion, though the severity of staining was significant in the abrasion group. The depth of homogenization was slightly more significant in the abrasion group. The rate of nuclear elongation in the epithelium of the hair follicles was significantly lower in the abrasion group. The results of this study revealed that certain morphological changes determined under a light microscope could help the differential diagnoses of electrical lesions, flame burns and abrasions. 相似文献
993.
Aghayev E Thali MJ Jackowski C Sonnenschein M Dirnhofer R Yen K 《Forensic science international》2008,176(2-3):183-186
Morphological findings in death due to hypothermia are variable and predominantly unspecific. Goal of this study was to check the usefulness of post-mortem cross-sectional imaging methods in the diagnosis of externally invisible findings in death due to hypothermia. Three consecutive forensic cases that died due to hypothermia were examined using post-mortem multi-slice computed tomography (MSCT) and magnetic resonance imaging (MRI) prior to autopsy. MSCT excluded traumatic skeletal and fatty tissue injury. Using MRI, it was possible to detect hemorrhages within the muscles of the back in all three cases, a so far unknown finding in death due to hypothermia. MRI also allowed the detection of hemorrhages in the iliopsoas muscles. Wishnewsky spots remained radiologically undetected using the present examination techniques. In conclusion, hemorrhages of the muscles of the back might serve as a new sign of death due to hypothermia; however, additional studies on their specificity are necessary. Post-mortem MRI is considered as a good diagnosing tool for muscular hemorrhages, with a great potential for examination and documentation. 相似文献
994.
Dorandeu A Coulibaly B Piercecchi-Marti MD Bartoli C Gaudart J Baccino E Leonetti G 《Forensic science international》2008,177(1):47-51
Determination of age at the time of death based on the observation of cranial sutures has led to numerous studies with sometimes contradictory results. The initial hypothesis being that suture closure is part of an age-related physiological process, the conflicting results have been interpreted by various authors as secondary to the choice of sutures, under the co-existing influence of pathological factors or genetic factors, or even independent of age. Despite these differences, macroscopic methods remain much used in anthropology and in forensic medicine. In our work, we evaluated the value of the degree of closure of the frontosphenoidal suture in estimating age at death of mature subjects, with the secondary objective of establishing a linear regression which could be used in routine practice. The study concerned bone specimens from individuals whose age, sex and medical history were known. Macroscopic observation was carried out on the ectocranial and endocranial sides according to four stages of closure previously defined. 290 sutures were taken from a population of whom two-thirds were men. The method can be repeated and reproduced and the regression established shows the confidence range for average error to be +/-1.5 years. While this result is of interest in terms of precision in prediction for a group of people, the prediction range is too great (+/-23 years) to be applicable to a single individual as part of a forensic procedure. 相似文献
995.
Tribulus terrestris is a nutritional supplement highly debated regarding its physiological and actual effects on the organism. The main claimed effect is an increase of testosterone anabolic and androgenic action through the activation of endogenous testosterone production. Even if this biological pathway is not entirely proven, T. terrestris is regularly used by athletes. Recently, the analysis of two female urine samples by GC/C/IRMS (gas chromatography/combustion/isotope-ratio-mass-spectrometry) conclusively revealed the administration of exogenous testosterone or its precursors, even if the testosterone glucuronide/epitestosterone glucuronide (T/E) ratio and steroid marker concentrations were below the cut-off values defined by World Anti-Doping Agency (WADA). To argue against this adverse analytical finding, the athletes recognized having used T. terrestris in their diet. In order to test this hypothesis, two female volunteers ingested 500 mg of T. terrestris, three times a day and for two consecutive days. All spot urines were collected during 48 h after the first intake. The (13)C/(12)C ratio of ketosteroids was determined by GC/C/IRMS, the T/E ratio and DHEA concentrations were measured by GC/MS and LH concentrations by radioimmunoassay. None of these parameters revealed a significant variation or increased above the WADA cut-off limits. Hence, the short-term treatment with T. terrestris showed no impact on the endogenous testosterone metabolism of the two subjects. 相似文献
996.
Quality assurance is one of the major issues in forensic analytical laboratories, where the need for a reference material (RM) has rapidly increased. RMs are very useful for method development and validation, internal quality control or proficiency tests. In the present study, we prepared a RM using drug-free hair for the determination of methamphetamine (MA) and its main metabolite, amphetamine (AP) according to the recommendations of ISO Guide 35. The concentrations of MA and AP were determined using two extraction methods, agitation with 1% HCl in methanol at 38 degrees C and ultrasonication with methanol/5M HCl (20:1), followed by gas chromatography/mass spectrometry (GC/MS) after derivatization with trifluoroacetic anhydride (TFAA). The assignment of values was conducted through the homogeneity study and characterization of the material. Furthermore, an internal proficiency test was performed with the prepared RM, of which the results were compared with those of the authentic hair RM prepared in our previous study. As a result, a hair RM containing MA and AP was prepared at the level of 4.86+/-0.69 ng/mg and 4.63+/-0.44 ng/mg, respectively. Most participants showed satisfactory performances in the internal proficiency test with the both RMs. The hair RM prepared in this study demonstrated its suitability for quality assurance in forensic laboratories. 相似文献
997.
998.
It might be critical to determine sex, body mass and age of the individual from skull in forensic medicine and anthropology. Our purpose in this study was to evaluate whether a relationship existed between the diploeic bone thickness measured from glabella, bregma, lambda, opisthocranion, and euryon regions and sex, age and body mass index of the individual. Glabella-opisthocranion, vertex-basion, euryon-euryon, basion-opisthion length were also determined for the same purpose. The anthropological landmarks were determined on sagittal and axial T1-weighted sequences and measurements were obtained on a workstation by two radiologists. A total of 107 subjects (F/M:59/48; mean age: 45.05+/-15.28, age range: 21-81) were included in the study. The mean body mass index was 25.51+/-4.44 [17.50-41]. There was a statistically significant linear correlation between age and diploe thickness from glabella, bregma, lambda, opisthocranion, right and left euryon. There was sexual dimorphism in all craniometric data including the distance between glabella-opisthocranion, vertex-basion, euryon-euryon, basion-opisthion, and calvarial volume. There was a statistically significant linear correlation between body mass index and basion-opisthion length. The diploe thicknesses from certain points of the calvarium are statistically related to each other. A standard cerebral MRI examination would be sufficient to obtain anthropological landmarks and craniometric data. According to this study, it might be possible to identify age, sex and body mass index of the individual from diploeic thickness and craniometric data. 相似文献
999.
Survey research in the field of intimate partner violence is notably lacking in its attention to contextual factors. Early measures of intimate partner violence focused on simple counts of behaviors, yet attention to broader contextual factors remains limited. Contextual factors not only shape what behaviors are defined as intimate partner violence but also influence the ways women respond to victimization, the resources available to them, and the environments in which they cope with abuse. This article advances methods for reconceptualizing and operationalizing contextual factors salient to the measurement of intimate partner violence. The analytic focus of the discussion is on five dimensions of the social context: the situational context, the social construction of meaning by the survivor, cultural and historical contexts, and the context of systemic oppression. The authors consider how each dimension matters in the measurement of intimate partner violence and offer recommendations for systematically assessing these contextual factors in future research. 相似文献
1000.
Although some community violence research has examined the context of community violence, including the social, economic, and structural organization of neighborhoods, more needs to be learned about family, school, and community-level factors that may promote and lessen the incidence and prevalence of community violence. In addition, further research is needed on various social, environmental, and contextual factors hypothesized to protect youth from exposure. This article (a) reviews and examines the relation between neighborhood context and risk of violence exposure, (b) reviews current literature on predictors of community violence and mental health and behavioral consequences for children and families adversely affected by community violence, (c) examines sources of resilience and community strengths that extend beyond the individual, (d) discusses the contributions and limitations of current conceptualizations of risk and resilience, and (e) highlights directions for future research. Information from this review can inform community and government efforts to lessen community violence through prevention and treatment. 相似文献