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A sensitive analytical method was developed for quantitative analysis of delta(9)-tetrahydrocannabinol (delta(9)-THC), 11-nor-delta(9)-tetrahydrocannabinol-carboxylic acid (delta(9)-THC-COOH), cannabinol (CBN) and cannabidiol (CBD) in human hair. The identification of delta(9)-THC-COOH in hair would document Cannabis use more effectively than the detection of parent drug (delta(9)-THC) which might have come from environmental exposure. Ketamine was added to hair samples as internal standard for CBN and CBD. Ketoprofen was added to hair samples as internal standard for the other compounds. Samples were hydrolyzed with beta-glucuronidase/arylsulfatase for 2h at 40 degrees C. After cooling, samples were extracted with a liquid-liquid extraction procedure (with chloroform/isopropyl alcohol, after alkalinization, and n-hexane/ethyl acetate, after acidification), which was developed in our laboratory. The extracts were analysed before and after derivatization with pentafluoropropionic anhydride (PFPA) and pentafluoropropanol (PFPOH) using a Hewlett Packard gas chromatographer/mass spectrometer detector, in electron impact mode (GC/MS-EI). Derivatized delta(9)-THC-COOH was also analysed using a Hewlett Packard gas chromatographer/mass spectrometer detector, in negative ion chemical ionization mode (GC/MS-NCI) using methane as the reagent gas. Responses were linear ranging from 0.10 to 5.00 ng/mg hair for delta(9)-THC and CBN, 0.10-10.00 ng/mg hair for CBD, 0.01-5.00 ng/mg for delta(9)-THC-COOH (r(2)>0.99). The intra-assay precisions ranged from <0.01 to 12.40%. Extraction recoveries ranged from 80.9 to 104.0% for delta(9)-THC, 85.9-100.0% for delta(9)-THC-COOH, 76.7-95.8% for CBN and 71.0-94.0% for CBD. The analytical method was applied to 87 human hair samples, obtained from individuals who testified in court of having committed drug related crimes. Quantification of delta(9)-THC-COOH using GC/MS-NCI was found to be more convenient than GC/MS-EI. The latter may give rise to false negatives due to the detection limit.  相似文献   
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A method for the selenium determination in a mother and her child's hair using palladium as a chemical modifier was optimized. The sample was digested with nitric acid and hydrogen peroxide and diluted to 5 ml. To achieve complete mineralization the samples were ashed at 1200 degrees C in the presence of palladium as a chemical modifier. The optimum atomization temperature was 1900 degrees C. The precision and accuracy of the method were studied using the reference material CRM 397. Results of calibration using aqueous standards and the standard addition method were compared. The method was applied to the selenium determination in 30 samples of the mother's and child's hair. The levels found were 0.54 +/- 0.34 microgram/g for mother's hair and 0.77 +/- 0.25 microgram/g for child's hair.  相似文献   
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A method for the simultaneous determination of cocaine (COC) and cocaethylene (CE) in human hair was developed, using solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) as analytical technique to identify and quantify the drugs. Selected ion monitoring (SIM) mode was used to obtain higher sensitivity. The deuterated-labeled analogues were used as internal standards. The detector response was linear for the drugs studied over the range 0.4-15 ng/mg, with correlation coefficients higher than 0.995. The coefficients of variation oscillated between 0.65% and 14.18% and the accuracy was in the range from 0.73% to 11.20%. The limits of quantitation and detection were found to be acceptable. Finally, this method was applied to 15 hair samples from cocaine users, obtaining positive results in all cases. The mean concentrations were 5.39 ng/mg (range: 0.43-8.98 ng/mg) for cocaine and 1.11 ng/mg (range: 0.42-2.23 ng/mg) for cocaethylene.  相似文献   
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The benefits of performance monitoring for public services are identified as greater transparency of objectives and accountability for results. This article considers recent experience in developing standards to evaluate efficiency and effectiveness of public services. In broad terms this is being done through performance information which is a much more encompassing concept than standards or indicators. Such information is an element of an accountability framework that provides greater management autonomy and flexibility and extends to the private sector which is increasingly providing, or involved with the provision of, public services.  相似文献   
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A fast and sensitive method for the determination of carboxyhemoglobin (COHb) in blood using derivative spectroscopy is described. The addition of sodium dithionite as a reducing agent is not required. The concentration interval studied was from 0.5% to 100% COHb.  相似文献   
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Introductory Address by Dr. AM Omar MP, Minister of Justice, at the South African Institute of International Affairs’ Workshop on ‘The Drug Trade in Southern Africa’, 5 June 1997, University of the Witwatersrand, Johannesburg.  相似文献   
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On 16 July 2004 the Australian Public Service Commission launched a new approach to leadership capability development for the public service. This approach, the Integrated Leadership System (ILS), is described as innovative and unique by the four speakers who make up this presentation—including Andrew Podger (AO), Public Service Commissioner, Jane Halton, Secretary of Health and Ageing, Anne Simic, Head of People, Qantas, and Dr Peter Shergold, Head of the Public Service and Secretary of the Department of Prime Minister and Cabinet.  相似文献   
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The Boston Gun Project is a problem-solving policing initiativeaimed at reducing homicide victimization among young peoplein the city of Boston. It represented an innovative partnershipbetween researchers and practitioners to assess the city's youthhomicide problem and implement an intervention intended to havepowerful impacts in the near term. In early 1996, a workinggroup representing a variety of law enforcement and social serviceagencies implemented an intervention that strategically respondedto gang violence, focused enforcement efforts on gun trafficking,and emphasized communication of the strategy to generate deterrence.The intervention is associated with a 60% decline in youth homicidevictimization (i.e., two fewer victims per month). There aresmaller declines in other measures of violence. The declinein youth homicide is sharp and occurs coincident with the introductionof the intervention. Competing hypotheses appear unable to accountfor the decline.  相似文献   
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