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911.
Toske SG Cooper SD Morello DR Hays PA Casale JF Casale E 《Journal of forensic sciences》2006,51(2):308-320
Laudanosine, reticuline, codamine, and laudanine are members of the tetrahydrobenzylisoquinoline family of natural products. These alkaloids are present in the opium poppy, Papaver somniferum, and are subsequently found as impurities in clandestinely processed morphine. Morphine is then synthesized to heroin using hot acetic anhydride. During the course of this study, it was determined that these four tetrahydrobenzylisoquinolines undergo degradation to a series of 18 neutral impurities when subjected to hot acetic anhydride. Based on the degradation pathway, these new impurities were categorized into two sets of impurities called the C1-acetates compounds and the stilbene compounds. Synthesis, isolation, and structural elucidation information is provided for the tetrahydrobenzylisoquinoline alkaloids, and the new neutral impurities have been studied. Several hundred authentic heroin samples were analyzed using an established heroin signature program method. This methodology features the detection of trace neutral impurities present in heroin samples. It was determined that all 18 new impurities were detected in various quantities in four different types of heroin samples. Analytical results featuring these new impurities are reported for South American-, Southwest Asian-, Mexican-, and Southeast Asian-type heroin samples. These new impurities, coupled with other established forensic markers, enhance the ability to classify illicit heroin samples. 相似文献
912.
The bullet evidence in the JFK assassination investigation was reexamined from metallurgical and statistical standpoints. The questioned specimens are comprised of soft lead, possibly from full-metal-jacketed Mannlicher-Carcano (MC), 6.5-mm ammunition. During lead refining, contaminant elements are removed to specified levels for a desired alloy or composition. Microsegregation of trace and minor elements during lead casting and processing can account for the experimental variabilities measured in various evidentiary and comparison samples by laboratory analysts. Thus, elevated concentrations of antimony and copper at crystallographic grain boundaries, the widely varying sizes of grains in MC bullet lead, and the 5-60 mg bullet samples analyzed for assassination intelligence effectively resulted in operational sampling error for the analyses. This deficiency was not considered in the original data interpretation and resulted in an invalid conclusion in favor of the single-bullet theory of the assassination. Alternate statistical calculations, based on the historic analytical data, incorporating weighted averaging and propagation of experimental uncertainties also considerably weaken support for the single-bullet theory. In effect, this assessment of the material composition of the lead specimens from the assassination concludes that the extant evidence is consistent with any number between two and five rounds fired in Dealey Plaza during the shooting. 相似文献
913.
Vogt S Mehlig A Hunziker P Scholer A Jung J González AB Weinmann W Marsch S 《Forensic science international》2006,161(2-3):216-220
We report the case of attempted suicide with amlodipine, chlorthalidone and mefenamic acid and subsequent medical intensive care measures which resulted in total recovery of a 42-year-old male. After admission to the medical intensive care unit the intoxicated patient was deeply hypotensive and needed fluid replacement, dobutamine and norepinephrine. Additionally insulin and calcium gluconate were given. Since hypotension persisted and the patient developed oliguria, terlipressin was applied and finally showed an effect on blood pressure and on urinary output. A volume overload of 7 L in the first 24 h resulted in a pulmonary edema. The patient was started on non-invasive ventilation with continuous positive airway pressure (CPAP) and frusemide was added to the therapy with good success. Quantitative determination of amlodipine in plasma samples was performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The highest amlodipine concentrations was measured in the plasma sample collected approximately 8 h after ingestion of the drug, and was 393 microg/L. Four days later, it was possible to stop the treatment with catecholamines, at that time the amlodipine plasma concentration had declined to 132 microg/L, still tenfold higher than therapeutic (5-18 microg/L). Elimination half-life of amlodipine is approximately 55 h. After 6 days in the intensive care unit the patient was transferred to psychiatric treatment. Intensive care management and plasma levels in this intoxication case are compared to data from literature on other cases. 相似文献
914.
915.
The case report of a serial killer who worked at several hospitals as a respiratory therapist is presented. The suspect was initially labeled a benevolent Angel of Death who ended the suffering of elderly patients through mercy killing. However, his subsequently declared motive for homicide was very different from other similar cases in medical settings. The application of new analysis techniques for the detection of pancuronium bromide in a series of aged exhumation tissues gave positive results and led to the resultant conviction of the therapist. 相似文献
916.
Hays PA 《Journal of forensic sciences》2005,50(6):1342-1360
A rapid, sensitive, accurate, precise, reproducible, and versatile method for determining the purity of reference drug standards and the routine analysis of illicit drugs and adulterants using proton (1H) Nuclear Magnetic Resonance (NMR) Spectroscopy is presented. The methodology uses a weighed sample dissolved in a deuterated solvent or solvent mixture containing a high purity internal standard. The NMR experiment employs 8 scans using a 45 second delay and 90 degrees pulse. In the determination of purity of reference standards, the number of quantitative determinations available is equal to the number of peak groups that are baseline resolved. The relative standard deviation (RSD) of these signals is usually < 1% for pure standards, and the results agree well with other purity determining methods. This method can also aid in the determination of correct molecular weight for standards containing an unknown number of waters of hydration or an unknown number of acids per drug in salts. Because the molar response for the hydrogen nucleus is 1 for all compounds, and since no separation media are used, only one linearity study is required to test a probe. In the presented study, the linearity of the NMR probe was determined using methamphetamine HCl dissolved in deuterium oxide (D2O) with maleic acid as the internal standard (5 mg) for a range of concentrations from 0.033 to 69.18 mg/ml with a resulting correlation coefficient of >0.9999 for all 6 methamphetamine peak groups. The spectra of complex illicit heroin, methamphetamine, MDMA, and cocaine samples are presented, as well as an extensive list of compounds, their solubilities and the solvent(s) and internal standard used. 相似文献
917.
After 20 months of interment in a deep grave, the decomposed body of the 81-year old testator of a will was exhumed to sustain the burden of proof that he lacked testamentary capacity when the will was rewritten two days prior to his death. The brain was mushy and pulverized with complete disappearance of the brainstem, cerebellum and subcortical ganglia. Small foci of relatively intact dorsal frontal neocortex were identified. Sections from these foci were stained with hematoxylin and eosin, bielchowsky silver stain and immunostains for beta amyloid peptide (betaA4), tau and alpha-synuclein. Despite severe autolysis and decomposition, the bielchowsky stain and the betaA4 immunostains showed preserved frequent neuritic amyloid plaques with very few residual neurofibrillary tangles. Cerebral Amyloid Angiopathy was present. At the present time this case represents the first documented and reported case of direct tissue diagnosis of Alzheimer's Disease pathology in a decomposed brain following long term burial in a deep grave. 相似文献
918.
919.
Patrick J. Kelley 《Ratio juris》2002,15(1):26-51
Both Holmes and Langdell believed that science was the model for all human inquiry and the source of all human progress. Langdell was influenced by an unsophisticated scientism, which led him to attempt to identify the true meaning of legal doctrines. Holmes was influenced by the sophisticated positivism of John Stuart Mill, which led him to attempt to reduce legal rules and doctrines to scientific laws of antecedence and consequence, justified only by their social consequences. Both Holmes and Langdell concluded that judges ought to decide a case by applying the rules established by precedent, without appeal to any special claims of justice and without appeal to any higher-order normative principle. 相似文献
920.