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41.
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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The main aim of this paper is to advance knowledge and (especially) theories about developmental and life‐course criminology (DLC). First, I review the widely accepted DLC findings that all DLC theories have been designed to explain. Second, I review more contentious and unresolved empirical DLC issues that might present challenges to DLC theories. Third, I describe my own DLC theory and specify how it addresses key empirical and theoretical questions. Fourth, I summarize five important DLC theories, by Catalano and Hawkins, Sampson and Laub, Moffitt, LeBlanc, and Thornberry and Krohn. Fifth, I identify differences in assumptions and predictions between my theory and the other five theories. Finally, I recommend a detailed comparison of the key features of all DLC theories, of their answers to key empirical and theoretical questions, and of their predictions regarding key unresolved empirical DLC issues.  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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Esophageal and tracheal fistulas, which occur in 0.05% of medicolegal autopsies, were demonstrated in three cases by a postmortem radiographic technique using silicone rubber/lead oxide as a contrasting medium that vulcanizes at room temperature. In one 83-year-old male, a tracheoesophageal fistula was detected, which had developed after surgical repair of an esophageal rupture caused by a flexible fiberoptic endoscope. In a second case, carcinoma of the esophagus in a 78-year-old male had eroded the trachea and arcus of the aorta creating a fatal tracheoesophagoaortic fistula. In a third case, 55-year-old female developed a tracheobrachicephalic artery fistula as a result of an infiltrating cystic adenocarcinoma of the trachea, resulting in a fatal hemorrhage into the trachea. The results of this study indicate that diagnostic radiologic methods using a vulcanized contrasting medium are useful in supplementing normal dissection in autopsy cases with suspected fistulas of the esophagus or trachea.  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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Blood previously acidified with aqueous saturated ammonium chloride solution was extracted with ethyl acetate. The dried extract was subjected to acetonitrile–hexane partition. The acetonitrile portion was analysed for the presence of acidic and neutral drugs by HPLC–DAD (200 mm×2.1 mm I.D. microbore ODS-Hypersil column) and GC–FID (25 m narrow-bore×0.25 mm I.D. HP-5 column with 0.33 μm film thickness). The protocol was found to be suitable for both clinical toxicology (including emergency toxicology) and postmortem toxicology. At least 66 drugs of interest were unequivocally identified by RRTs (HPLC) and UV spectra (DAD) match while another 12 were unequivocally identified by double RRTs match (HPLC and GC). Quantitation was facilitated by incorporating calibration blood standards in each assay batch. The five drugs most commonly encountered in clinical blood specimens (1150 cases) were: paracetamol (47.4% of the cases); chlormezanone (6.6%), theophylline (1.74%), naproxen (1.65%) and mefenamic acid (1.56%). The following drugs were detected in toxicologically significant quantities in postmortem blood specimens (245 cases): phenobarbitone (1.22% of the cases), naproxen (0.82%), chlormezanone (0.82%), theophylline (0.82%), carbamazepine (0.41%) and paracetamol (0.41%).  相似文献   
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