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131.
This study examined whether flossing the teeth is a more effective collection method in recovering spermatozoa than conventional swabbing techniques. It was hypothesized that inclusion of flossing as a collection method would extend the recovery of spermatozoa to longer postcoital intervals (PCIs). Eighteen individuals provided 174 oral cavity samples. Successful recovery of spermatozoa was assessed with respect to the collection method and reported activity in the oral cavity during the PCI. Samples were subjected to a differential extraction procedure prior to microscopic evaluation of the extracted pellet. The results indicate that swabbing is more effective than flossing when the PCI falls within 1.5–12 h. However, spermatozoa were recovered from seven floss samples where the corresponding swabs gave negative results. When combining the results from the two collection methods, the percentage of subjects from whom spermatozoa are recovered increases for each PCI beyond the 0‐h interval.  相似文献   
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Five cases of vehicular homicide are presented in which the determination of an occupant's role in a motor vehicle collision was an important medicolegal question. The identification of the occupant's role in a motor vehicle collision can be determined by the forensic pathologist. The investigation that coordinates an examination of injury mechanisms, occupant kinematics, vehicle dynamics, and trace evidence will facilitate such a determination. This determination protects the innocent passenger, when faced with criminal or civil charges, from being falsely prosecuted as the driver. The examination of the above-mentioned components in a multi-occupant collision takes on particular forensic importance when a surviving driver claims to be a passenger: the victim rather than the assailant.  相似文献   
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The chief clinical and analytical aspects of the suicide of a 21-year-old male with psychiatric problems by parenteral administration of a 200 g/l aqueous solution of paraquat are described. Paraquat levels were determined in plasma, urine, kidney, liver and lung after autopsy. Tissue damage was studied by electron microscopy. The death ensued from pulmonary dysfunction 15 days after hospital admission.  相似文献   
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Fetal death due to acute carbon monoxide poisoning is rarely reported in the medical literature. Of the eight cases found in literature review, only one documented the fetal carboxyhemoglobin concentration. This paper reports a fetal death due to accidental nonlethal maternal carbon monoxide intoxication in which both maternal and fetal carboxyhemoglobin concentrations were obtained. The corrected carboxyhemoglobin concentration was 61% at the time of death in utero, while the maternal carboxyhemoglobin was measured at 7% after one hour of supplemental oxygen. The authors review the mechanisms of fetal death and emphasize the different carbon monoxide kinetics in the fetal circulation.  相似文献   
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Abstract:  Screening methods capable of identifying DNA samples that will not yield short tandem repeat (STR) profiles are desired. In the past, quantitation methods have not been sensitive enough for this purpose. In this study, low level DNA samples were used to assess whether Quantifiler™ has a minimum quantitation value below which STR profiles would consistently fail to be detected. Buccal swabs were obtained and the DNA extracted, quantified, and serially diluted to concentrations ranging from 0.002 to 0.250 ng/μL. Samples were analyzed once with Quantifiler™, followed by Profiler Plus™ amplification and capillary electrophoresis analysis. An absolute minimum value below which STR results were unobtainable could not be defined. From the 96 low level samples tested, STR loci (including one full profile) were successfully amplified and detected from 27% of the samples "undetected" by Quantifiler™. However, no STR alleles were detected in 73% of these "undetected" samples, indicating that Quantifiler™ data may be useful for predicting STR typing success.  相似文献   
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Abstract: The routine identification of controlled substances and adulterants during forensic chemistry analysis often involves the identification of counter ions or salt forms present in an exhibit. Here, the use of the compound meso‐octamethylcalix(4)pyrrole (C4P) during salt‐form identification analysis is presented. C4P is a commercially‐available, anion‐binding agent that can be reacted with a controlled substance or adulterant, resulting in the sequestration of anionic species, usually present as counter ions to the active ingredient. Formation of noncovalent complexes between the cyclic host C4P compound and anionic guests is investigated using electrospray ionization–mass spectrometry (ESI–MS). Complexes with chloride, bromide, iodide, nitrate, and acetate are readily observed and mass spectrometry analysis provides identification via molecular weight characterization. Chloride and bromide complexes are also characterized by the isotopic distribution of their molecular ions. Formation of host–guest complexes is not observed for sulfate and phosphate salts, presumably due to steric hindrance and energetically unfavorable conditions.  相似文献   
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Political Behavior - Although Barack Obama won the presidency in 2008, some Whites nevertheless penalized him because of his race. In part, these penalties involved persistent rumors about his...  相似文献   
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