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A nurse was accused of attempting to murder her anesthesiologist husband on two occasions by administering to him a neuromuscular blocking agent. In both episodes, urine specimens were obtained from the victim shortly after the suspected assaults. The samples were initially tested fluorometrically using Rose Bengal dye as a pairing agent. Both were presumptively positive for pancuronium. Confirmation of these results was achieved by pairing the drug with potassium iodide, extracting the complex, and submitting the extract to thin-layer chromatography (TLC) cleanup, elution at the appropriate retardation factor (Rf), and, finally, gas chromatography/mass spectrometry (GC/MS) analysis in the selected-ion monitoring mode. The two quaternary amines of pancuronium appear to undergo pyrolytic N-demethylation in the injection port to yield an entity amenable to capillary column gas chromatography. The mass spectrum of the compound consists of a base peak of m/z 322, with additional fragments of 292, 323, 338, and 397 m/z, each of which was monitored. The confirmed positive findings were instrumental in adjudicating the case. 相似文献
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C A Nichols P D Guerry M A Sens 《The American journal of forensic medicine and pathology》1990,11(1):71-73
A small wound found on the ear of a homicide victim was inflicted by either a knife or a sharp fragment of ceramic. To test the potential usefulness of cytologic examination of wound edges for fragments of inert material from the assault weapon, the wound was rinsed and cytologic filters were prepared from the retained rinsing material. The particulate matter present on filters included microscopic fragments of crockery admixed with blood and other tissue components. This observation supported other physical evidence that the wound was caused by the sharp edge of a ceramic crock rather than by the knife. This case demonstrates the potential usefulness of cytologic examination of wound edges. 相似文献
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Toxicology analyses and other forensic science data were used to examine the mechanisms through which ethanol increased the risk for death caused by injected street preparations of heroin. The authors studied 505 victims of fatal heroin overdose and compared subjects who had concentrations of blood ethanol greater than 1000 mg/L (n = 306) with those who had concentrations less than, or equal to 1000 mg/L (n = 199). We found significant negative correlations between concentrations of ethanol and morphine (a heroin metabolite) in blood (R2 = 0.11, P = 0.0001 for log10-transformed variables) as well as between concentrations of blood ethanol and bile morphine (R2 = 0.16, P = 0.0001 for log10 bile morphine versus blood morphine). Toxicologic evidence of infrequent heroin use was more common in decedents with blood ethanol concentrations greater than 1000 mg/L than in those with lower concentrations. Our data suggest that ethanol enhances the acute toxicity of heroin, and that ethanol use indirectly influences fatal overdose through its association with infrequent (nonaddictive) heroin use and thus with reduced tolerance to the acute toxic effects of heroin. 相似文献