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Gorman C  Park A 《Time》2002,160(4):32-39
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Park A 《Time》2002,160(7):53
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An accurate and simple method was developed to determine the level of toluene in urine and blood quantitatively by using the gas chromatography/mass spectrometry (GC/MS) with headspace--solid phase microextraction (HS-SPME) technique. An assembly of SPME with a replaceable extraction fiber, coated with 100 microm polydimethylsiloxane, was used. The detection limit of toluene in blood and urine with HS-SPME technique was 10 times higher than that with headspace (HS) technique. To compare the HS-SPME with HS technique for the determination of toluene in biological fluids, blood and urine samples from glue sniffers were analyzed by both methods. The level of toluene by the two techniques was highly correlated: the correlation coefficient (r2) between the two sets of values were 0.98 and 0.96 in urine and blood, respectively.  相似文献   
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This study was designed to compare the qualitative results and concentrations of methamphetamine (MA) and its metabolite amphetamine (AP) in head hair and hair collected from different parts of the body (axillae and pubis). Hair from subjects (N = 14) suspected MA users was simultaneously collected. Hair preparation involved washing step, fine cutting, overnight extraction, derivatization by the trifluoroacetic anhydride, and gas chromatography/mass spectrometry (GC/MS) using selective ion monitoring. In this study, we found a good correlation of the qualitative results for MA between head hair and hair on other parts of the body, but there were some differences in concentrations of MA and AP. Namely, the concentrations of MA and AP were higher in axillary and pubic hair than in head hair.  相似文献   
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The population genetic data of 18 X-chromosomal short tandem repeat (STR) markers DXS6807, DXS8378, DXS9895, DXS9902, DXS6810, DXS7132, DXS981, DXS6800, DXS9898, DXS6789, DXS101, DXS6797, GATA172D05, GATA165B12, HPRTB, GATA31E08, DXS8377, and DXS7423 were analyzed in samples of unrelated 220 males and 181 females from Korean population. The exact test for genotype distribution of the markers showed no significant deviation from the Hardy-Weinberg equilibrium. Allele frequencies between male and female samples were not significantly different in all examined markers. All examined males and females showed different hemizygotic haplotype and combined genotypes, respectively. Four cases of mutation were found in GATA172D05, GATA31E08, DXS7132, and HPRTB from the analysis of 95 father-child-mother trios. Details of X chromosomal STRs in Koreans would be useful in paternity tests and forensic purposes as well as whole X-chromosomal mapping studies.  相似文献   
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The prevalence and age distribution of 3,4-methylenedioxymethamphetamine (MDMA) and 3,4-methylenedioxyamphetamine (MDA) in hair samples by gas chromatography/mass spectrometry (GC/MS) were studied. The recoveries obtained from hair were 97% and 99% for MDMA and MDA, respectively. The inter- and intra-assay precision and accuracy were determined. Out of 791 hair samples, 44 (5.6 %) contained MDMA and/or MDA. Out of these 44 subjects, urinalyses from 35 were negative for both MDMA and MDA, while only 9 were positive. We also evaluated concentrations of MDMA and MDA, and the metabolite-to-parent drug ratios. This study showed that the abuse of MDMA or MDA was found principally among young adults and male abusers. We found the epidemiology of ecstasy users in Korea between March 2002 and April 2003.  相似文献   
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