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V R Spiehler 《Journal of forensic sciences》1989,34(5):1104-1115
Case data from 200 morphine-involved deaths (Spiehler, V. and Brown, R., Journal of Forensic Sciences, Vol. 32, No. 4, July 1987, pp. 906-916) were analyzed for patterns and relationships using artificial intelligence (AI) computer software. Case parameters were blood unconjugated morphine, blood, brain, and liver total morphine, sex, age, frequency of use, time of death after injection, cause of death, and presence of other drugs. The programs used were Expert 4 (Biosoft-Cambridge), BEAGLE (Warm Boot, Ltd.), and KnowledgeMaker (Knowledge Garden Inc.). Interpretation was defined as estimating the dose, response, and time after drug dosing. The AI programs were used to advise on time and response outcomes for cases, to calculate the probability of the estimate being true, to develop rules for interpretation of morphine-involved cases, and to diagram a decision tree. On known cases the AI programs were successful 70 to 90% of the time in classifying the cases as to response and time. No data on dose were available in this database. The success rate in individual cases was proportional to the program-estimated probability. All three programs found the case parameters of most value in predicting response to be blood unconjugated morphine, blood total morphine, and liver total morphine. The case data most useful in estimating time of death since drug injection were blood unconjugated morphine, percent unconjugated morphine in blood, and brain total morphine. The rule induction programs found that morphine overdoses were characterized by blood unconjugated morphine greater than 0.24 micrograms/mL, liver morphine greater than 0.50 to 0.75 micrograms/g, brain morphine greater than 0.08 micrograms/g or greater than blood unconjugated morphine, and percent blood unconjugated morphine greater than 37%. Rapid deaths were characterized by percent unconjugated morphine greater than 44 to 50%; blood unconjugated morphine, as a function of other drugs present, greater than 0.09 to 0.21 micrograms/mL; and brain total morphine greater than 0.16 to 0.22 micrograms/g. This work demonstrates that inexpensive AI programs commercially available for personal computers can be useful in interpretation in forensic toxicology. 相似文献
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The authors describe a special case of suicide, committed by a self-constructed nailgun. The inshot-wound, localized in the mouth, primarily remained undiagnosed. The patient survived two weeks and died of pulmonary embolism. 相似文献
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The acetaldehyde accumulation in blood during the equilibration time of samples processed by gas-liquid chromatographic headspace technique is reported. The quantitative loss of blood ethanol concentration is recorded at various temperatures and times of the preheating process.When the equilibration process is performed at 40 °C, minimal errors, due to ethanol oxidation, are observed. 相似文献
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The biology-policy interface: Theories of pathogenesis,benefit valuation and public policy formation
This paper reviews some of the basic concepts of cost and risk-benefit analysis in the context of toxic chemical regulation and discusses several critical complexities inherent in the practical application of this methodology. The broad qualitative use of risk-benefit analysis can be an important aid to the decision-making process. It is concluded, however, that the full-scale incorporation of a rigorous form of risk-benefit analysis into the regulatory process is inappropriate at this time and could have significant and unintended consequences.The authors wish to express their gratitude to their colleagues, Professors Norm Carruthers, Denton Marks and Dean Uyeno, and an anonymous referee for their instructive comments on an earlier draft of this paper. 相似文献