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971.
Forensic archaeologists and criminal investigators employ many different techniques for the location, recovery, and analysis of clandestine graves. Many of these techniques are based upon the premise that a grave is an anomaly and therefore differs physically, biologically, or chemically from its surroundings. The work reviewed in this communication demonstrates how and why field mycology might provide a further tool towards the investigation of scenes of crime concealed in forest ecosystems. The fruiting structures of certain fungi, the ammonia and the postputrefaction fungi, have been recorded repeatedly in association with decomposed mammalian cadavers in disparate regions of the world. The ecology and physiology of these fungi are reviewed briefly with a view to their potential as a forensic tool. This application of mycology is at an interface with forensic archaeology and forensic taphonomy and may provide a means to detect graves and has the potential to estimate postburial interval. 相似文献
972.
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
973.
The article describes problems related to immunochemical screening-tests with special regard to benzodiazepines, which are commonly used for therapeutic purposes. Focal points are adulteration, manipulation and handling of samples, the selection of cut-off-values, specificity and cross-reactivity, influence of biotransformation and frequently observed pitfalls in the interpretation of the analytical results. 相似文献
974.
975.
When the use of traditional forensic identification methods such as fingerprints or dental radiographs is difficult or impossible, identification by DNA analysis has proven valuable. In situations such as explosions or airplane crashes, identification is even more difficult because human remains are often fragmented and may be commingled. Teeth are a useful source of DNA and can often survive extreme environmental conditions. However, teeth may be fragmented into several identifiable regions. Therefore it is important to determine if DNA is present in forensically significant yields in all regions of the tooth. The main objectives of this study were to determine which region(s) of the tooth contains quantifiable DNA, if all regions contain similar yields of DNA and whether there is enough DNA in all regions to justify DNA extraction from a found tooth fragment. Results demonstrate that there is sufficient quantity of DNA in the crown body, root body, and root tip to support DNA extraction. Additionally, the root body is the region with the highest yield of DNA. This information will aid forensic DNA analysts in producing a useful DNA profile in a timely and cost-effective manner. 相似文献
976.
977.
Baker AM Johnson DG Levisky JA Hearn WL Moore KA Levine B Nelson SJ 《Journal of forensic sciences》2003,48(2):425-428
Diphenhydramine is an antihistamine available in numerous over-the-counter preparations. Often used for its sedative effects in adults, it can cause paradoxical central nervous system stimulation in children, with effects ranging from excitation to seizures and death. Reports of fatal intoxications in young children are rare. We present five cases of fatal intoxication in infants 6, 8, 9, 12, and 12 weeks old. Postmortem blood diphenhydramine levels in the cases were 1.6, 1.5, 1.6, 1.1 and 1.1 mg/L, respectively. Anatomic findings in each case were normal. In one case the child's father admitted giving the infant diphenhydramine in an attempt to induce the infant to sleep; in another case, a daycare provider admitted putting diphenhydramine in a baby bottle. Two cases remain unsolved; one case remains under investigation. The postmortem drug levels in these cases are lower than seen in adult fatalities. We review the literature on diphenhydramine toxicity, particularly as it pertains to small children, and discuss the rationale for treating these cases as fatal intoxications. 相似文献
978.
979.
980.