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851.
Mechanisms of unexpected death in tuberous sclerosis   总被引:2,自引:0,他引:2  
Tuberous sclerosis complex is a protean autosomal dominant disorder characterized by multifocal tissue lesions arising from defects in cellular migration, proliferation, and differentiation. It has an association with sudden death. In the current study, review of all cases of sudden death due to tuberous sclerosis was undertaken at the Forensic Science Centre in Adelaide, Australia from 1991 to 2001, in addition to an analysis of cases from the literature. There were two local cases where unexpected death had occurred in individuals with known tuberous sclerosis, involving a 31-year-old male (epilepsy), and a 24-year-old female (massive hemorrhage into a renal angiomyolipoma). Fatal mechanisms in cases of tuberous sclerosis may be associated with underlying cardiovascular, renal and cerebral abnormalities. Sudden death may be due to cardiac arrhythmia, epilepsy, and intra-tumoral hemorrhage with additional complications including cardiac outflow obstruction, obstructive hydrocephalus, aneurysm rupture, and spontaneous pneumothorax. An awareness of the highly variable tissue manifestations of tuberous sclerosis and the mechanisms that may be responsible for death is necessary to establish correctly the diagnosis in occult cases (possibly with molecular confirmation), and to chart accurately organ changes in individuals with established disease.  相似文献   
852.
The fingernails of Mary Sullivan, the last victim of the Boston Strangler, were examined to determine if any genetic information about the murderer could be obtained. The nails were extremely friable necessitating the development of new techniques for isolating and purifying DNA. DNA yields from nails were optimized by using a NaOH-based preparation technique, which was simple, efficient, and minimized handling. Methods for selectively and thoroughly removing exogenous material on nails were also developed through use of a species-specific PCR assay, wherein mitochondrial DNA from the nail could easily be differentiated from DNA of contaminating cells.  相似文献   
853.
854.
A method was developed to screen for pepper spray residue using instruments and methods other than those techniques commonly employed to analyze chemical residue (i.e.. gas chromatography mass spectrometry-GCMS or liquid chromatography mass spectrometry-LCMS). The method employed gas chromatography (GC), thin layer chromatography (TLC), and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) to screen for dried pepper spray stains. Pepper sprays from nine different manufacturers were investigated. Capsaicin and dihydrocapsaicin were identified and unique IR reflectance spectra are presented. An additional five compounds were presumptively found. Results showed that a particular stain could be characterized as a pepper-based stain.  相似文献   
855.
Within the field of forensic dentistry, the detection, collection, and analysis of bitemarks remains one of the most contentious areas. Attempts at the production of consensus documents have produced documents such as the ABFO's Guidelines for Bitemark Evidence Collection. Despite this, the range of differing analysis techniques, allied with a varied opinion base on the robustness of bitemark conclusions has led to polarized views within the profession. The purpose of this study was to survey forensic dentists to obtain their views on a number of crucial components of bitemark theory and contentious areas within the discipline. Using a web-based survey, 14 questions were asked of respondents. Seventy-two odontologists completed the survey, with 38% being of Diplomate status, 10% had completed 20 or more bitemark cases, and 20% between 10 and 20 cases, 91% of respondents believed that the human dentition was unique, with 78% believing that this uniqueness could be represented on human skin during the biting process. Seventy percent believed that they could positively identify an individual from a bitemark, and 22% stated that the statistical tool, the product rule, should be applied to bitemark conclusions. Over half of the odontologists used overlays for bitemark analysis. with a digital method of production the most popular. The implications of these and other findings are discussed.  相似文献   
856.
Supraphysiologic doses of testosterone are associated with increased aggression that is hypothesized to be a function of testosterone serum concentrations, mood, and personality. The study attempted to characterize this relationship among weightlifters who were users (n = 10) and nonusers (n = 18) of anabolic steroids. Participants were interviewed using the Modified Mania Rating Scale and Hamilton Rating Scale for Depression to assess mood, the Buss-Durkee Hostility Inventory (BDHI) and Point Subtraction Aggression Paradigm (PSAP) to assess aggression, and the Personality Disorder Questionnaire (PDQ-R) to assess personality. Blood samples were obtained for the determination of total, free, and weakly bound testosterone. Comparisons of continuous variables between testosterone users and non-users were performed with a parametric (unpaired t-test) or non-parametric (Mann-Whitney) test where appropriate. Correlations with testosterone were examined separately for testosterone users and non-users, using Spearman rank correlation. The subjective (BDHI) and objective (PSAP) assessments of aggression found that supranormal testosterone concentrations were associated with increased aggression. However, the PDQ-R results suggest that this finding was confounded by the personality disorder profile of the steroid users, because steroid users demonstrated Cluster B personality disorder traits for antisocial, borderline, and histrionic personality disorder.  相似文献   
857.
The presence of cocaine in illicit drug samples is still being determined in some laboratories using spot tests and microcrystal tests. Seventeen chemical species were tested using three different spot tests (Wagner, Marquis, and cobalt thiocyanate followed by stannous chloride reactions) and two microcrystal tests (gold chloride and platinic chloride) to determine whether the results could be differentiated from the results of these tests on cocaine. The data obtained indicated that nine of the 17 compounds gave results similar to those from cocaine using the three spot tests, but that the results from microcrystal testing allowed for differentiation of all nine compounds from cocaine.  相似文献   
858.
The analysis of fatty acids from common vegetable oils was investigated for application to forensic casework. A base-catalyzed transesterification of the fatty acids to fatty acid methyl esters using tetramethylammonium hydroxide was simple, rapid, straightforward and inexpensive. Canola, corn, olive, peanut, safflower, soybean and sunflower oils were able to be classified based on their fatty acid methyl ester profiles. Using gas chromatography-mass spectrometry, the detection limits for canola, corn, olive, peanut and safflower oils were determined to be 0.4 mg/mL or less and 0.2 mg/mL or less for soybean and sunflower oils.  相似文献   
859.
860.
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   
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