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511.
Despite the increasing incidence of illicit use of gamma-hydroxybutyrate (GHB), little information is available documenting levels of the drug in GHB fatalities. We measured GHB levels in postmortem blood, brain and hair specimens from a suspected overdose case by gas chromatography/mass spectrometry (GC/MS) following solid phase extraction (SPE) and derivatization with bis(trimethyl-silyl) trifluoroacetamide (BSTFA). Examination found 330 microg/mL GHB in femoral blood and 221 ng/mg GHB in frontal cortex brain tissue, values higher than those typically reported in the literature. The hair shaft was negative for GHB whereas the plucked root bulbs with outer root sheath attached (2,221 ng/mg) and root bulbs after washing and removal of the outer root sheath (47 ng/mg) contained the drug. Our results are consistent with an acute single dose of GHB and, as the toxicology screen was negative for other drugs of abuse, emphasize the significant danger of this drug. 相似文献
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Mark Schneider Gregory Elacqua Jack Buckley 《Journal of policy analysis and management》2006,25(3):577-601
Skeptics of school choice are concerned that parents, especially low‐income ones, will not choose schools based on sound academic reasoning. Many fear that, given choice, parents will sort themselves into different schools along class lines. How‐ever, most surveys find that parents of all socioeconomic groups cite academic aspects as important when choosing a school. Moreover, almost no parents refer to the social composition of the student body. Many advocates of choice hold up these results as proof that choice will produce desirable outcomes. However, these results may not be reliable because they may simply be verbal responses to survey items rather than indicators of actual behavior. In this research, we report on the search behavior of parents in the Metropolitan Region of Santiago, Chile, examining how they construct their school choice sets and comparing this to what they say they are seeking in choosing schools. The data indicate that parental decisions are influenced by demographics. Based on this evidence, we argue that unfettered choice may reduce the pressure on schools to improve their performance and could potentially increase stratification. © 2006 by the Association for Public Policy Analysis and Management 相似文献
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Somers GR Smith CR Perrin DG Wilson GJ Taylor GP 《The American journal of forensic medicine and pathology》2006,27(1):64-69
Sudden unexpected death due to clinically undiagnosed neoplasia in infancy and childhood (SUDNIC) is a rare phenomenon, with only small numbers of cases reported in the literature. In the majority of instances, the tumors involve critical structures within the heart or central nervous system and include gliomas, medulloblastomas, rhabdomyomas, and neoplasms of stromal elements. A 20-year retrospective review of autopsy records from the Hospital for Sick Children, Toronto, was performed (1984-2003, n = 4926), and 7 cases of SUDNIC were identified (0.14%). In addition, 1 case was obtained from the files of the Children's and Women's Health Centre of British Columbia, Vancouver. Diagnoses included 2 cases of acute leukemia (1 myelogenous, 1 lymphoblastic), 2 cases of mediastinal lymphoblastic lymphoma (pre-T cell type), 1 papillary fibroelastoma of the mitral valve prolapsing into and totally occluding the left anterior descending coronary artery, 1 medulloblastoma, 1 Wilms tumor associated with fatal intraperitoneal hemorrhage, and 1 widely disseminated gastric carcinoma. These cases demonstrate that infants and children may have minimal or no symptoms in the presence of significant disease and highlight the need for a thorough autopsy examination in cases of sudden unexpected death in infancy and childhood. 相似文献
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Mikolaenko I Robinson CA Davis GG 《The American journal of forensic medicine and pathology》2002,23(3):299-304
Interpretation of the concentration of a drug is more difficult when a combination of drugs is present in a decedent's blood. An increase in deaths resulting from co-intoxication with methadone and a benzodiazepine led the authors to perform a retrospective study of cases examined at the Jefferson County Coroner/Medical Examiner Office. They found 101 deaths wherein methadone was detected in the blood. Based on the drugs detected in the blood, these 101 cases were grouped into four categories: (1) pure methadone intoxication, (2) intoxication with methadone and benzodiazepine, (3) intoxication with methadone and other drugs excluding benzodiazepine, and (4) intoxication with methadone, benzodiazepines, and other drugs. Methadone was the sole intoxicant in 15 cases, with a mean concentration of 0.27 mg/L. Benzodiazepines were the most frequently detected co-intoxicant (60 of 101 cases). Benzodiazepine was the only co-intoxicant in 30 cases, and the mean methadone concentration in those 30 cases was 0.599 mg/L. Higher levels of methadone may occur in acute intoxication with methadone and benzodiazepine because benzodiazepines compete with methadone for methadone receptors. Higher levels of methadone may occur with chronic abuse of methadone and benzodiazepines because over time, benzodiazepines inhibit the hepatic enzymes that metabolize methadone. 相似文献
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