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791.
A method was developed for simultaneously analyzing cocaine (COC), benzoylecgonine (BZE), norbenzoylecgonine (BNE), norcocaine (NCOC), ecgonine (ECG), ecgonine methyl ester (EME), m-hydroxybenzoylecgonine (HBZE), anhydroecgonine methyl ester (AEME), cocaethylene (CE), norcocaethylene (NCE), and ecgonine ethyl ester (EEE) in blood, urine, and muscle. Available deuterated analogs of these analytes were used as internal standards. Proteins from blood and muscle homogenate were precipitated with cold acetonitrile. After the removal of acetonitrile by evaporation, the supernatants and urine were subjected to solid-phase extraction. The eluted analytes were converted to their hydrochloride salts and derivatized with pentafluoropropionic anhydride and 2,2,3,3,3-pentafluoro-1-propanol. The derivatized products were analyzed by a gas chromatograph (GC)/mass spectrometer by selected ion monitoring. The limit of detection (LOD) for COC, BZE, NCOC, EME, CE, NCE, and EEE was 2ng/ml, while the LODs for BNE, ECG, HBZE, and AEME were 25, 640, 50, and 13 ng/ml, respectively. This method was successfully applied in analyzing 13 case samples from aviation accident pilot fatalities and motor vehicle operators. AEME concentrations found in the 13 samples were consistent with those produced solely by the GC inlet pyrolysis of COC controls in blood. Anhydroecgonine cannot be used as a marker for the abuse of COC by smoking because it is also pyrolytically produced from COC metabolites on the GC inlet. The developed method can be effectively adopted for analyzing COC and related compounds in urine, blood, and muscle by a single extraction with increased sensitivity through formation of hydrochloride salts and using a one-step derivatization. 相似文献
792.
X-chromosomal markers are particularly useful for solving complex problems relating to kinship and deficiency paternity analysis. In the present study, population genetics data of four X-chromosomal short tandem repeats (STRs) DXS8378, HPRTB, DXS7423 and DXS7132 were obtained by analyzing 500 unrelated Chinese individuals (250 males and 250 females). Population genetics data obtained from the Chinese were compared with those of the Asian and European population. Mutations in X-chromosomal markers were analyzed based on a total of 61 proven father-child and 45 proven mother-child pairs. 相似文献
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R R Fysh M C Oon K N Robinson R N Smith P C White M J Whitehouse 《Forensic science international》1985,28(2):109-113
Radioimmunoassay, high-performance liquid chromatography and capillary gas chromatography-mass spectrometry were used to detect and measure LSD in the first reported case of fatal poisoning by LSD. The levels found in ante-mortem serum and plasma and in post-mortem blood, liver blood and stomach contents are given. 相似文献
800.
M. K. Shams 《公共行政管理与发展》1985,5(2):157-167
The wide range of management training programmes for public servants in the Philippines is closely integrated into career development plans and involves practical work by trainees at village level. Trainees are required to reside in a village for varying periods of time to familiarize themselves with life among the rural poor. The aim is to train local people in self-reliant project management as well as to train civil servants in rural development. Close relations with villagers provides an invaluable experience for city-based officials. However, little effort is made to identify the needs of the rural poor. Client groups are selected at meetings dominated by local officials. Officials tend to be “hosted” by relatively wealthy families. Linkages with government agencies at the local level are not made and there is little organizational development among the rural poor to ensure the continuation of projects after the withdrawal of trainees. Nevertheless, the “barangay immersion” approach to management training for rural development has considerable potential. 相似文献