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961.
A simple technique is presented for the longitudinal sectioning of hair samples without the need for any embedding medium. The technique applies to single hair samples that are placed in a groove of a particular depth and can either be scraped or cut to the desired level. Planar sections are obtained that reveal the internal structure of the sample and are ideal for the application of surface analytical techniques for the study of internal transverse and longitudinal distributions of xenobiotics.  相似文献   
962.
963.
Mitochondrial DNA analysis of a maggot crop can identify the corpse a maggot has been feeding on. Analysis of the crop could be useful in a criminal investigation if maggots are found at a suspected crime scene in the absence of a body, or if there is a question of whether a maggot used in postmortem interval estimations moved onto the corpse from another food source. Such analysis can also resolve a chain of custody dispute if it has been suggested that larval samples have been switched. When recovering DNA from a maggot crop, the analyst must be careful to avoid external contamination. We investigated the effects of three simple wash methods developed to reduce external contamination. Maggots raised on pig liver and intentionally contaminated with cow blood were washed using water, 20% bleach, or a solution containing the enzyme DNase. Only washing the maggots in 20% bleach reduced the amount of vertebrate DNA amplified from the maggots' exteriors. No wash method affected the ability to recover DNA from the maggot crops.  相似文献   
964.
965.
966.
The authors evaluated the usefulness of the postmortem biochemical analysis of ionic ratios in different parts of the heart and their relation to cardiac damage caused by chest trauma, as observed by anatomopathologic study. Fifty-nine 59 cases were studied, selected from routine necropsies, and samples were taken from different sites of cardiac tissue. The cause of death was trauma in 40 cases and nontraumatic causes in 19 cases. The object of this study was to analyze the levels of Na+, K+, Ca+2, Mg+2, and Zn+2 in different zones of the heart, and the relationship between intracellular and extracellular ion ratios and the different causes of death and any anatomopathologic alterations observed. The biochemical tests revealed a possible relation between the ionic values and cause of death. Alterations in cell membrane permeability and corresponding modification of the ionic ratios were produced earlier than histologic alterations, which need longer to establish themselves whether or not they follow a traumatic process.  相似文献   
967.
An ordnance-disposal expert was killed while disposing of a cache of explosives. The likely position of the body was reconstructed by modeling the explosion as an omnidirectional emission of particles from a model of the explosion site and noting the distribution of particles on a model of a human. The applications and limitations of this method in reconstructing the events and correlation with the injuries noted at autopsy are discussed.  相似文献   
968.
To investigate socioemotional influences on children's eyewitness accuracy, we examined children's reports for activities they were motivated to conceal. Forty-eight 3–6-year-old children participated in a standardized play session with their mothers. Half of the children were told by an experimenter not to play with certain toys, but did so at the urging of their mothers, who told their children to keep the play activities secret. The remaining children were not restricted from playing with the toys, nor told by their mothers to keep the play activities secret. Later, all children were interviewed about the activities with free narrative and detailed questions. Half were given an interview that consisted of highly suggestive questions; half were given an interview consisting of specific, less suggestive questions. Results indicated that older children who were instructed to keep events secret withheld more information than did older children not told to keep events secret. Younger children's reports were not significantly affected by the secret manipulation. There were no significant effects associated with interview type. We discuss implications for understanding the development of children's knowledge and use of secrecy, and applications of the research to issues that arise when child witnesses give reports in legal contexts.  相似文献   
969.
A 2-month-old infant girl died suddenly as a result of torsion of the uterine adnexa. The infant was found unresponsive in bed and was pronounced dead shortly after her arrival at a hospital. There were no antecedent signs of illness. At autopsy, the right ovary and right fallopian tube were twisted and were dark purple, swollen, and necrotic. The right ovary was enlarged by a follicle cyst 4 cm in diameter, which likely precipitated the torsion. The mechanism of death was unclear but may have resulted from the release of cytokines produced in response to necrotic adnexal tissue. Fatal uterine adnexal torsion has been reported rarely in infants; in all those cases there were antecedent symptoms. Torsion of the uterine adnexa should be included in the differential diagnosis of sudden death in infancy.  相似文献   
970.
Self-immolation is an uncommon method of suicide, and its occurrence in South Africa is thus far unknown. This study aimed to determine the prevalence of self-immolation deaths and to establish a profile of these cases and the circumstances under which this condition occurs. A 5-year (1996-2000) retrospective review at a mortuary in Durban, South Africa, was conducted. Data were obtained from the Department of Forensic Medicine, the Medical Research Council's National Injury Mortality Surveillance System, and police and hospital records. During the study period, there were 12339 nonnatural deaths, of which 696 (5.6%) were suicides. Self-immolation accounted for 69 (0.6%) of all nonnatural deaths and 69 (9.9%) of all suicides. The subjects had a mean age of 31.2 years and were predominantly female (76.8%) and black (81.2%). The mean burn surface area was 63.3%, and the mean injury severity score was 36.9. Accelerant use was documented in 53 (76.8%) of cases, and paraffin was preferred. All cases occurred indoors. The proportion of suicides due to self-immolation in our study is excessive when compared with international studies that report figures between 0.9% and 2.2% of suicides. Additional studies are necessary to further elucidate the reasons for this discrepancy.  相似文献   
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