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The possible contribution of poppy seed foods to positive opiate urinalysis results, especially from foods available in the Pacific Rim area, has recently become an issue for the U.S. Army Forensic Toxicology Drug Testing Laboratory in Hawaii. To assess the likelihood of this possible contribution, seven different poppy seed food products were consumed by male and female volunteers, and urine specimens were collected at time increments up to either 24 or 72 h. Specimens were evaluated for opiates using Roche Abuscreen radioimmunoassay (RIA), and all RIA positive specimens were analyzed for morphine and codeine using gas chromatography/mass spectrometry (GC-MS). Poppy seed cake, bagels, muffins, and rolls did not contain sufficient quantities of poppy seeds to give rise to opiate positive specimens by U.S. Department of Defense (DOD) GC-MS cutoff levels (morphine = 4000 ng/mL, codeine = 2000 ng/mL), although a number of specimens were positive by National Institute on Drug Abuse (NIDA) cutoff levels (morphine and codeine = 300 ng/mL). However, ingestion of poppy seed streusel or Danish pastry led to confirmed morphine and codeine positive specimens, irrespective of the use of DOD or NIDA confirmation cutoff values. In addition, significant amounts of codeine were observed in a number of these specimens. These findings argue against the unqualified application of previously published quantitative guidelines for eliminating poppy seed ingestion as a possible cause for a positive opiate urinalysis result.  相似文献   
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Research has indicated that school factors such as communal school organization and student bonding are predictive of school disorder, with greater communal organization and greater student bonding leading to less delinquency and victimization. Data from a nationally representative sample of 254 public, nonalternative, secondary schools were used to examine structural equation models representing hypothesized relationships among communal school organization, student bonding, and school disorder. The hypothesis that communally organized schools would have less disorder held true for teacher victimization and student delinquency, but not for student victimization. In addition, the hypothesis that the relationship between communal school organization and school disorder would be mediated by student bonding was supported for student delinquency, but not for teacher victimization.  相似文献   
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We investigated the differences in the levels of carboxyhemoglobin (COHb), cyanide (HCN) and petroleum fuels (gasoline and kerosene) between left and right ventricular bloods from fire victims. COHb was slightly, and HCN and petroleum fuels were markedly higher levels in the left than those in the right. These effects were so called 'first pass phenomena' due to the circulation, diffusion and metabolization before the deaths of fire victims.  相似文献   
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Michael Levin 《欧亚研究》1997,49(8):1519-1525
James D. White, Karl Marx and the Intellectual Origins of Dialectical Materialism. Basingstoke: Macmillan, 1996, xii + 416 pp., £40.00 h/b, £14.99 p/b.  相似文献   
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