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891.
Sex assessment of skeletal remains plays an important role in forensic anthropology. The pelvic bones are the most studied part of the postcranial skeleton for the assessment of sex. It is evident that a population-specific approach improves rates of accuracy within the group. The present study proposes a discriminant function method for the sex assessment of skeletal remains from a contemporary Mexican population. A total of 146 adult human pelvic bones (61 females and 85 males) from the skeletal series pertaining to the National Autonomous University of Mexico were evaluated. Twenty-four direct metrical parameters of coxal and sacral bones were measured and subsequently, sides and sex differences were evaluated, applying a stepwise discriminant function analysis. Coxal and sacra functions achieved accuracies of 99% and 87%, respectively. These analyses follow a population-specific approach; nevertheless, we consider that our results are applicable to any other Hispanic samples for purposes of forensic human identification.  相似文献   
892.
The mechanisms leading to death from anaphylaxis after insect sting involve antigen cross-linkage of antibody molecules that activate immunoglobulin receptors on inflammatory cells. The aim of our study was to investigate the pathomorphology and the expression of C5aR in fatal anaphylaxis in a patient after a fatal insect sting. A 38-year-old women was stung by a honeybee. C5R1 expression was detected in many dilated capillaries in the lungs. Pulmonary epithelial cells did not bind the monoclonal antibody for C5R1; however, intensive cytoplasmic staining was detected in endothelial cells. The findings of this case provide evidence for an active role of complement in fatal anaphylaxis elicited by bee venom. C5aR detection could be useful in the identification of sudden death cases because of unwitnessed fatal insect sting cases. Authors can recommend this immunohistochemical analysis on all sudden unexpected deaths outdoors where a possible bee sting might occur.  相似文献   
893.
Abstract: Salivary DNA is encountered in many crimes, such as sexual assaults and murders. In this study, saliva from three male donors was deposited on the skin of three female recipients. The amount of male salivary DNA remaining on the female skin was measured over a 96‐h period using the Quantifiler? Y Human Male DNA Quantification Kit. In eight of the nine experiments, a full male DNA profile matching the donor was obtained even after 96 h. In addition, the study showed that the concentration of salivary DNA varied from donor to donor and from day to day. The efficiency of two recovery methods, wet and dry swabbing and minitaping, was compared. The results indicate the tapelift method gave higher DNA recovery. This study also examined the secondary transfer of salivary DNA from skin to fabrics. Cotton and polyester give higher DNA transfer than leather.  相似文献   
894.
895.
The purpose of this work was to study the appropriateness of polyethylene bags for the preservation of explosive specimens. To this end, specimens of two types of dynamites, Goma-2 EC, containing nitroglycol (EGDN) and dinitrotoluene (DNT), and Goma-2 ECO, containing only EGDN, were placed individually inside bags and introduced into hermetically sealed glass jars, which were stored for a period of time. Losses of volatile compounds were studied by headspace analysis using gas chromatography coupled to mass spectrometry (GC-MS). The cross-contamination between dynamites was studied by using high performance liquid chromatography with mass spectrometry (HPLC-MS) to analyse the extracts obtained after a sequential solvent extraction of these specimens. Polyethylene bags permit the loss of volatile compounds since EGDN and DNT were detected in the headspaces of the jars. Moreover, cross-contamination between dynamites was also demonstrated since DNT content decreased in the dynamite containing this compound and increased in the dynamite that had not contained it.  相似文献   
896.
Normally, the identification of the LSD drug is performed by forensic laboratories, using the Ehrlich spot test. However, this is a nonspecific analysis. Additionally, the Brazilian Federal Police has identified the presence of a new compound in seized blotters: 9,10-dihydro-LSD, an uncontrolled substance. In this work, easy ambient sonic-spray ionization mass spectrometry in the positive ion mode, EASI(+)-MS, was used to characterize LSD and 9,10-dihydro-LSD compositions directly from the surface of blotters. The presence of LSD in the seized blotter samples were also confirmed via high-performance liquid chromatography with ultraviolet detector. In a set of 41 blotters analyzed by EASI(+)-MS, 28 showed positive results for LSD, seven for 9,10-dihydro-LSD, and another six samples showed negative results for both LSD and 9,10-dihydro-LSD. The combination of thin layer chromatography with EASI-MS also demonstrated to be a relatively simple and powerful screening tool for forensic analysis of street drugs.  相似文献   
897.
Abstract: Suicidal decapitation is seldom encountered in forensic medicine practice. This study reports the analysis of a suicide committed by a 31‐year‐old man with a self‐fabricated guillotine. The construction of the guillotine was very interesting and sophisticated. The guillotine‐like blade with additional weight was placed in a large metal frame. The movement of the blade was controlled by the frame rails. The steel blade was triggered by a tensioned rubber band after releasing the safety catch. The cause of death was immediate exsanguination after complete severance of the neck. The suicide motive was most likely emotional distress after the death of his father. In medico‐legal literature, there has been only one similar case of suicidal complete decapitation by a guillotine described.  相似文献   
898.
This paper presents the first referenced case on a death by traumatic asphyxia in a folding bunk bed. A middle-aged man was found dead in a hotel room trapped into a lower folding bunk bed where he had been sleeping after a party. The autopsy showed signs of asphyxia and excluded signs of struggle and sexual intercourse. Toxicological analyses revealed alcohol intoxication. A differential diagnosis of the manner of death including a technical study of the bed which contributed to understand the circumstances of death was made. The medico-legal investigation of the case strongly supported the hypothesis of an accidental death by traumatic asphyxia.  相似文献   
899.
900.
The first synthesis of the 2,3-isomers of MDPV, butylone and methylone is reported. The isomers were characterised by (1)H and (13)C NMR spectroscopy and compared to the corresponding 3,4-isomers. A GC method is described which separates the 3,4- and the 2,3-isomers from each other. IR spectra of the 2,3-isomers are also compared with the corresponding 3,4-isomers. Two seized drug samples were analysed by GCMS and the samples were found to contain the 3,4-isomers.  相似文献   
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