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V R Spiehler D Reed R H Cravey W P Wilcox R F Shaw S Holland 《Journal of forensic sciences》1975,20(4):647-655
The quantitative results (accuracy and precision) for determination of opiates by radioimmunoassay (RIA), enzyme immunoassay (EMIT), and spectrofluorometry on split samples are compared. A variety of physiological samples were studied, including random urine from a methadone maintenance clinic and postmortem urine, blood, bile, brain, and lung tissue from heroin-induced or heroin-related deaths. The opiate concentrations detected by the two immunoassay methods were in good agreement with each other in the absence of interfering substances which are believed to react with the antimorphine antibodies. The immunoassay results were in agreement within the relative standard deviation with the fluorometry results in 55% of the urine samples and 80% of the blood samples. The immunological methods are superior to fluorometry for quantitation of morphine in urine samples due to quenching interferences in fluorometry from urine. They were comparable to fluorometry for quantitation of morphine in blood samples. 相似文献
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In recent years in Atlanta, homicide has been the most common cause of death in males 20–40 years of age. To study homicide trends in this city we analyzed data for 591 resident victims of criminal homicide in two time perid. 1961–1962 and 1971–1972. Large increases occurred in the homicide rates for both black and white residents. In both races, these rate increases could be accounted for almost entirely by homicides involving firearms Homicide rates for black and whites in 1971–1972 were highest in census tracts with low indices of socioeconomic status; this association was found only for homicides in which the victim and assailant were relatives or acquaintances. There was little geographic overlap between areas with high rates of homicide in the home and high numbers of homicides in public. Using population-based rates facilitates comparisons of homicide occurrence between time periods and/or places. 相似文献
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