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981.
A cardiac concussion is caused by a sudden, nonpenetrating, localized impact to the chest that is theorized to result in almost simultaneous sudden death from a disruption to the conductive system. The detailed external/internal forensic examination of the body reveals no evidence of structural, pathologic, or histologic signs of trauma to the heart. A cardiac concussion is a rare and often overlooked cause of sudden death. This type of sudden death is typically seen among younger individuals participating in sports involving projectiles and, to a lesser degree, where collisions occur. Cardiac concussions are clinically, pathologically, and chemically different from a cardiac contusion. The objective of this paper will be to define cardiac concussion, differentiate between cardiac concussion and cardiac contusion, and describe the clinical and pathologic features of a 32-year-old white male who died of a cardiac concussion following a collision with a catcher during a softball game. The civil ramification of incorrectly diagnosing the manner of death in cases of death involving a cardiac concussion will also be addressed.  相似文献   
982.
983.
The amphetamine derivative 3,4-methylenedioxymethamphetamine (MDMA, "Ecstasy" is a currently used or abused designer drug and fatalities are frequently encountered in forensic practice. However, the question remains open whether an MDMA blood level can be toxic or even potentially lethal. In order to provide insight in the interpretation of a detected MDMA concentration, the distribution of MDMA and its metabolite 3,4-methylenedioxyamphetamine (MDA) in various body fluids and tissues was studied and discussed in two different fatalities. Apart from peripheral blood samples (such as femoral and subclavian blood), various blood samples obtained centrally in the human body and several body fluids (such as vitreous humour) were examined. In addition, various tissues such as cardiac muscle, lungs, liver, kidneys, and brain lobes were analysed. In contrast to the peripheral blood levels, high MDMA and MDA levels were found in cardiac blood and the majority of the organs, except for the abdominal adipose tissue. The high concentrations observed in all lung lobes, the liver and stomach contents indicate that post-mortem redistribution of MDMA and MDA into cardiac blood can occur and, as a result, blood sampled centrally in the body should be avoided. Therefore, our data confirm that peripheral blood sampling remains "the golden standard". In addition, a distinct difference in peripheral blood MDMA concentrations in our two overdose cases was established (namely 0.271 and 13.508 microg/ml, respectively). Furthermore, our results suggest that, if a peripheral blood sample is not available and when putrefaction is not too pronounced, vitreous humour and iliopsoas muscle can be valuable specimens for toxicological analysis. Finally, referring to the various mechanisms of death following amphetamine intake, which can result in different survival times (e.g. cardiopulmonary complications versus hyperthermia), the anatomo-pathological findings and the toxicological results should be considered as a whole in arriving at a conclusion.  相似文献   
984.
Allele frequencies for 16 short tandem repeats (STR) loci were determined with a sample of 230-300 unrelated individuals from the population of Rio de Janeiro, Brazil. The loci are the most commonly used in forensic and paternity testing, being analysed by the Identifiler (Applied Biosystems) and PowerPlex 2.1 (Promega) commercial kits. It was proved that Penta E and D18S51 are the most polymorphic loci.  相似文献   
985.
Y-STR polymorphism in Central Anatolian Region of Turkey   总被引:2,自引:0,他引:2  
Eight Y-chromosome specific STR (Y-STR) loci including DYS19, DYS388, DYS389I, DYS389II, DYS390, DYS391, DYS392 and DYS393 were investigated in a group of males from Central Anatolian Region of Turkey. Healthy 59 males living in this region for at least three generations were included in the study. PCR analysis was carried out with Y-STR specific primers on genomic DNA obtained from peripheral blood samples and size determination of PCR products was performed by silver staining following 6% polyacrylamide gel electrophoresis (PAGE). DYS388 was found to be the locus with lowest diversity (D) whereas DYS389II was the locus with highest diversity. The current study presented a framework of variation for the eight Y-STR loci in Central Anatolian population.  相似文献   
986.
Hallucinogenic fungi synthesize two controlled substances, psilocin and psilocybin. Possession of the fungal species that contain these compounds is a criminal offence in North America. Some related species that are morphologically similar, do not contain the controlled substances. Therefore, unambiguous identification of fungi to the species level is critical in determining if a mushroom is illegal. We investigate a phylogenetic approach for the identification of species that contain the psychoactive compounds. We analyzed 35 North American specimens representing seven different genera of hallucinogenic and non-hallucinogenic mushrooms. We amplified and sequenced the internal transcribed spacer region of the rDNA (ITS-1) and a 5' portion of the nuclear large ribosomal subunit of rRNA (nLSU rRNA or 28S). ITS-1 locus sequence data was highly variable and produced a phylogenetic resolution that was not consistent with morphological identifications. In contrast, the nLSU rRNA data clustered isolates from the same species and separated hallucinogen containing and non-hallucinogen containing isolates into distinct clades. With this information, we propose an approach that combines the specificity of PCR detection and the resolving power of phylogenetic analysis to efficiently and unambiguously identify hallucinogenic fungal specimens for legal purposes.  相似文献   
987.
988.
In this study, we analyzed allelic sequences of 10 novel Y-specific STR loci, DYS454, DYS510, DYS513, DYS520, DYS542, DYS544, DYS552, DYS561, DYS587 and DYS593, surveyed the distribution of haplotypes in a Chinese Han population. Extracted DNA was amplified with PCR, followed by a horizontal non-denaturing polyacrylamide gel electrophoresis with discontinuous buffer system. Purified alleles were sequenced on DNA sequencer (ABI Model 377) to verify the number of motif repeats. The number of alleles observed at each locus ranged from 3 to 8, yielding 102 haplotypes in 103 unrelated males samples. The allele diversity values for each locus ranged from 0.2099 (DYS544) to 0.7523 (DYS552). The haplotype diversity using all these loci was 0.9998. Our study revealed that they were valuable Y-specific markers for forensic applications.  相似文献   
989.
Reticuline (a precursor of opium alkaloids) was detected and characterised as its trimethylsilyl ethers, acetyl esters and methyl ethers by GC-EIMS and GC-CIMS in opium and the urine of opium users after hydrolysis by acid or beta-glucuronidase as coextractive of morphine. Because this compound cannot be detected in heroin and poppy seeds, it is suggested as a differentiating marker between opium and heroin use, opium and poppy seeds use, or opium and "pharmaceutical" codeine use in cases when opiate use has been confirmed by detection of morphine and codeine in the urine. As well as being a constituent of opium, reticuline in the urine of opium users may also result from the metabolic demethylation of the three other benzyltetrahydroisoquinoline opium alkaloids: codamine, laudanosine and laudanine.  相似文献   
990.
Firearm-related injuries are a leading cause of morbidity and mortality in South Africa. This retrospective autopsy study included all firearm-related fatalities seen at a central mortuary in Durban. These cases had initially been assessed by a clinician before death, from July 1998 to June 1999.A total of 322 cases of fatal gunshot wounds were reviewed. Medical records and postmortem findings were compared by data capture onto a spreadsheet. Twenty-eight cases were excluded because of surgical alteration of the wounds, making autopsy evaluation impossible. In 50.7% of cases, the number of wounds was correctly identified and in 55.1% the position was correctly identified. In only 36.1% of cases were the entry and exit wounds correctly identified. The total number of missed wounds was 504 (48.3% of cases). The majority of missed wounds were on the upper limbs (25%), with the anterior trunk (21.8%) and lower limbs (18.5%) making up the remainder. This study demonstrates that physicians in South Africa do not adequately document and interpret gunshot wounds, which may influence the treatment of the patient and have medicolegal consequences. Emphasis should be placed on undergraduate and postgraduate teaching for physicians to correctly identify, interpret, and document firearm wounds.  相似文献   
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