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991.
The purpose of this study was to evaluate the ability of two amphetamine class screening reagents to exclude ephedrine (EPH), pseudoephedrine (PSEPH), and phenylpropanolamine (PPA) from falsely producing positive immunoassay screening results. The study also sought to characterize the prevalence and concentration distributions of EPH, PSEPH, and PPA in samples that produced positive amphetamine screening results. Approximately 27,400 randomly collected human urine samples from Navy and Marine Corps members were simultaneously screened for amphetamines using the DRI and Abuscreen online immunoassays at a cutoff concentration of 500 ng/mL. All samples that screened positive were confirmed for amphetamine (AMP), methamphetamine (MTH), 3,4-Methylenedioxyamphetamine (MDA), 3,4-Methylenedioxymethamphetamine (MDMA), EPH, PSEPH, and PPA by gas chromatography/mass spectrometry (GC/MS). The DRI AMP immunoassay identified 1,104 presumptive amphetamine positive samples, of which only 1.99% confirmed positive for the presence of AMP, MTH, MDA, or MDMA. In contrast, the online AMP reagent identified 317 presumptive amphetamine positives with a confirmation rate for AMP, MTH, MDA, or MDMA of 7.94%. The presence of EPH, PSEPH, or PPA was confirmed in 833 of the 1,104 samples that failed to confirm positive for AMP, MTH, MDA, or MDMA; all of the 833 samples contained PSEPH. When compared to the entire screened sample set, PSEPH was present in approximately 3%, EPH in 0.9%, and PPA in 0.8% of the samples. The results indicate that cross reactivities for EPH, PSEPH, and PPA are greater than reported by the manufacturer of these reagents. The distribution of concentrations indicates that very large concentrations of EPH, PSEPH, and PPA are common. 相似文献
992.
DNA profiling using STRs on the 310 and 3100 Genetic Analyzers routinely generates electropherograms that are analyzed with the GeneScan software available from the instrument's manufacturer, Applied Biosystems. Users have been able to choose from three different smoothing options that have been known to result in significant differences in the peak heights that are reported. Improvements in the underlying algorithm of the most recent version of the software also result in significant and somewhat predictable differences in peak height values. Laboratories that have performed validation studies using older versions of GeneScan should either reanalyze the data generated in those validation studies with the newest version of the software or otherwise take into consideration the systematically higher peak height values obtained as they begin following the recommendation of the manufacturer and use the new algorithm. 相似文献
993.
A simple method for analyzing nitrite in urine has been developed to confirm and quantify the amount of nitrite in potentially adulterated urine samples. The method involved separation of nitrite by capillary electrophoresis and direct UV detection at 214 nm. Separation was performed using a bare fused silica capillary and a 25 mM phosphate run buffer at a pH of 7.5. Sample preparation consisted of diluting the urine samples 1:20 with run buffer and internal standard, and centrifuging for 5 min at 2500 rpm. The sample was hydrodynamically injected, then separated using -25 kV with the column maintained at 35 degrees C. The method had upper and lower limits of linearity of 1500 and 80 microg/mL nitrite, respectively, and a limit of detection of 20 microg/mL. The method was evaluated using the National Committee for Clinical Laboratory Standards (NCCLS) protocol (Document EP10-A2), and validated using controls, standards, and authentic urine samples. Ten anions, ClO-, CrO4(-2), NO3-, HCO3-, I-, CH3COO-, F-, SO4-, S2O8(-2), and Cl-, were tested for potential interference with the assay. Interferences with quantitation were noted for only CrO4(-2) and S2O8(-2). High concentrations of Cl- interfered with the chromatography. The method had acceptable accuracy, precision, and specificity. 相似文献
994.
The pathomorphology of intoxication of alcohol surrogates is described. A high frequency rate of DIC-syndrome is shown for the condition. A majority of thrombi accumulates at places with the highest concentrations of toxic substances as well as at those places, through which poisoning substances are brought out of the body, i.e. in the liver (since toxic substances are introduced perorally) and kidneys. Thrombi were detected in all internals, including the brain, in lethal intoxication. The immediate toxic effect from methanol and from higher spirits can matter in the genesis of changes, including acute swelling and chromatolysis with subsequent cell death. Exclusively cerebral or coagulopathic-cerebral types of thanatogenesis were registered in studied case of intoxication. 相似文献
995.
996.
997.
While analyzing the available published data, we found significant differences in definition of alleles of the HUMCD4 polymorphic chromosome locus. It is an obstacle for comparing the expertise results obtained while using the locus as molecular individualization system in different laboratories and, as a consequence, it hinders the use of the said marker in building up a reference database. The structure of the HUMCD4 locus was analytically investigated and the distribution of the locus alleles was systemized in a sample of 407 persons (citizens of Russia who are not blood relatives) within the present case study for the purpose of a detailed definition of its allele's characteristics. We worked out recommendations related with the nomenclature standardization of alleles of the HIMCD4 locus and specified the main population features of the locus polymorphism on the bases of the studied sample of Russia's citizens. The results can be used as reference parameters in interpreting the findings of the molecular-genetic identification expertise and examinations and in building up databases. 相似文献
998.
This study examined effects of clothing cues on children's identification accuracy from lineups. Four- to 14-year-olds (n = 228) saw 12 video clips of individuals, each wearing a distinctly colored shirt. After watching each clip children were presented with a target-present or target-absent photo lineup. Three clothing conditions were included. In 2 conditions all lineup members wore the same colored shirt; in the third, biased condition, the shirt color of only one individual matched that seen in the preceding clip (the target in target-present trials and the replacement in target-absent trials). Correct identifications of the target in target-present trials were most frequent in the biased condition, whereas in target-absent trials the biased condition led to more false identifications of the target replacement. Older children were more accurate than younger children, both in choosing the target from target-present lineups and rejecting target-absent lineups. These findings suggest that a simple clothing cue such as shirt color can have a significant impact on children's lineup identification accuracy. 相似文献
999.
Suppression of environmental science 总被引:1,自引:0,他引:1
Kuehn RR 《American journal of law & medicine》2004,30(2-3):333-369
1000.
McGee SM McGee DN McGee MB 《The American journal of forensic medicine and pathology》2004,25(4):334-337
A healthy 31-year-old male abstinent from drug abuse during his recent incarceration developed slurred speech, a severe headache, and left-sided hemiparesis prior to his eventual death 9.5 hours after inhalation of methamphetamine. On postmortem examination, inspection of the brain revealed bilateral subarachnoid hemorrhage, with a prominent intralobar hemorrhage centered within the right frontal cerebral hemisphere. No evidence of vasculitis, infarction, intraventricular hemorrhage, or ruptured aneurysm could be observed. While this is not the first report of a methamphetamine-related stroke, this report describes the autopsy findings of an intracerebral hemorrhage secondary to methamphetamine abuse on autopsy and compares the findings and antemortem history to previously reported methamphetamine cerebral vascular deaths. 相似文献