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In the forensic science laboratory, the recovery of spermatozoa from vaginal swabs, or vaginal cells from penile swabs, can help determine if sexual intercourse may have taken place. There are several methods used to recover spermatozoa and cells from the swabs before visualisation on a microscope slide and most of these methods use water. Phosphate buffered saline (PBS) is a non-toxic solution used in many biological laboratories. Unlike water, PBS prevents cells rupturing or shrivelling up due to osmosis. This study demonstrates that PBS can be used for the extraction of spermatozoa and cells from swabs and that PBS does not affect subsequent DNA profiling.  相似文献   
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Toxicologic findings in the USS Iowa disaster.   总被引:5,自引:0,他引:5  
The toxicologic results from the 47 victims of the explosion on the USS Iowa are presented. Good correlation between carboxyhemoglobin saturations and cause of death was found. There were no correlations between blood cyanide concentrations and causes of death. Volatile analysis suggested postmortem ethanol production rather than antemortem ethanol ingestion. No drugs except nicotine were detected in any of the victims.  相似文献   
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A mock jury study was conducted to test the hypothesis that perceptions of a witness can be biased by presumptuous cross-examination questions. A total of 105 subjects read a rape trial in which the cross-examiner asked a question that implied something negative about the reputation of either the victim or an expert. Within each condition, the question was met with either a denial, an admission, or an objection from the witness's attorney. Results indicated that although ratings of the victim's credibility were not affected by the presumptuous question, the expert's credibility was significantly diminished—even when the question had elicited a denial or a sustained objection. Conceptual and practical implications of these findings are discussed.This research was supported by funds provided to the first author by the Bronfman Science Center.  相似文献   
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A review of the available literature does not reveal a plausible explanation as to why the incisal edges of maxillary anterior teeth do not always mark clearly. Generally, the mandibular incisal edges do mark with some consistency. This paper demonstrates through test bites on skin that the answer lies in the position of the mandible.  相似文献   
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Postmortem examination of a former professional basketball player revealed an abnormal heart, most notably a single coronary artery. The literature on single coronary arteries is briefly reviewed, and the possible mechanism which caused the patient's condition is considered. This case is particularly unusual because of the patient's profession, which is so physically demanding.  相似文献   
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