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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
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The relationships between the inert tension of the head and the morphologic substrates of brain injuries were under study. A comparative clinical and morphologic analysis of lethal contusion and axonal injuries underlie this investigation. Differences in the neurologic semeiotics and CT data in such injuries are presented. The authors discuss the mechanisms of the physical processes in the skull, resulting in focal and diffuse injuries of the brain. Quantitative assessment of the traumatic cerebral substrates is given and relations of these parameters to the conditions of the head trauma (the direction of the external injurious factor action) and the clinical picture are shown. The results of this study may be useful in establishing some circumstances of craniocerebral injuries. 相似文献
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A large number of passerine birds, mainly greenfinches, were found dead or dying in a hedgerow close to a field of onions recently sprayed with sodium monochloroacetate (SMCA). An analytical method is described for isolating monochloroacetic acid from bird tissues, as its potassium salt, by ion exchange chromatography. The ion exchange eluate is evaporated to dryness, acidified, extracted with ether and the ethereal extract methylated with diazomethane. The concentration of the methyl ester of monochloroacetic acid is determined using the Mass Selective Detector in the selected ion mode. Chemical analysis confirmed the exposure of the birds to SMCA. It is calculated that 50 microliter of spray contained the lethal dose of SMCA for a greenfinch. 相似文献