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31.
Determination of methamphetamine and amphetamine in hair was performed by gas chromatography/mass spectrometry using stable isotope-labeled internal standards, 2-methylamino-1-phenylpropane-2,3,3,3-d4 and 2-amino-1-phenylpropane-2,3,3,3-d4. Extraction of hair with methanol/5M hydrochloric acid (20:1) using ultrasonication was chosen as the standard method. The calibration curves for amphetamines in the hair were linear from 1 to 100 ng/mg (r greater than 0.99). The detection limit was 0.5 ng/mg at the 95% confidence level. The coefficients of variation (CV) (n = 8) of analysis using the spiked hair with methamphetamine were from 0.7 to 6%. The CV (n = 8) of analysis of the methamphetamine abuser's hair was 17.5%. Sectional analysis of monkey and human hair after methamphetamine ingestion suggested a good correlation between the duration of drug use and drug distribution in the hair.  相似文献   
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A simple and sensitive method is described for quantitative analysis of chlorpromazine in blood, serum, urine and tissue homogenate. The chlorpromazine cation radical produced by adding perchloric acid and 2,3-dichloro-5,6-dicyano-p-benzoquinone to the sample can be detected by the ESR method at room temperature. The sensitivity limit is 10 ng, that is, 20 μl of the solution containing 0.5 μg chlorpromazine/ml. The time needed for the measurement is within 10 min. The chlorpromazine radical thus produced is very stable; for example, 95% of the radical was observed after 24 h. The advantage of this method is discussed by comparing with the ordinary spectrophotometry which requires the purification of the sample.  相似文献   
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This article assesses whether police Field Training Officers (FTOs) display patterns of attitudes that distinguish them from non-field training officers. The analysis focuses on attitudes toward four important groups: fellow officers, immediate supervisors, top managers, and neighborhood residents. Interview data used were collected from Indianapolis Police Department (IPD) during the summer of 1996. Findings show that FTOs are more critical of their immediate supervisors and district managers than non-FTOs, whereas FTOs and non-FTOs hold similar attitudes toward their co-workers and neighborhood residents. Implications for future research and policy are discussed.  相似文献   
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The purpose of the present study was to identify salivary molecules carrying the ABH blood group antigens in Koreans and to investigate the changes in these antigens according to processing and storage of saliva samples. Secretor or non-secretor phenotypes and salivary components carrying the ABH antigens were identified in 90 subjects, 30 subjects in each ABO blood group, by SDS-PAGE and immunoblotting. Saliva samples were then obtained from 12 secretors-two males and two females in each ABO blood group and aliquots of both fresh saliva samples and their supernatants after centrifugation were stored at room temperature, 4, -20 and -70 degrees C. The same experiments were performed after 1, 3 and 6 months to investigate changes in the blood group antigens. In all 68 secretors, high-molecular-weight salivary mucin (MG1) was found to be the primary carrier of the ABH antigens. A salivary component of approximately 80 kDa also carried H antigen in seven saliva samples of 22 blood type O secretors. The blood group antigens were better detected in centrifuged samples. In saliva samples preserved at room temperature and 4 degrees C, the blood group antigens were either not detected or detected as degraded molecules. No change was found in the blood group antigens in saliva samples preserved at -20 and -70 degrees C for 6 months.  相似文献   
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This study investigated the relationship between neighborhood factors and juvenile serious offenders in Wayne County, Michigan. Wayne County is home to Detroit, a city with a glorious past but a bleak future. Administrative data were linked to tract-level census characteristics that proxy for social disorganization structural factors. Results by negative binomial regressions found significant associations in the expected direction with concentrated disadvantage, concentrated affluence, and inequality. Concentrated immigration, however, was insignificantly related to juvenile serious offending, and residential stability increased rather than decreased offending. These counter-theoretical results might be due to the presence of homes inhabited by students and young professionals and the vibrant Latino immigrant communities. The stark contrasts this analysis documented, combined with the high correlation of economic conditions to juvenile crime, demand urgent and radical responses to completely transform impoverished neighborhoods in Wayne County.  相似文献   
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The optimum method for analyzing glyceryl rosinate by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was studied. The performances of dithranol, anthracene, and 2,5-dihydroxybenzoic acid, pyrene, trans,trans-1,4-diphenyl-1,3-butadiene, 9-nitroanthracene, indole-3-acrylic acid and retinoic acid as a matrix agent, and those of sodium trifluoroacetate (NaTFA) and silver trifluoroacetate (AgTFA) as a cationization agent were measured. Dithranol showed higher signal to noise ratio and lower base-line, and AgTFA showed better performance than NaTFA. In this study, however, NaTFA was chosen since the ester peaks with high signal to noise ratios were observed, and the spectra of sodium-cationized molecules are simpler than those of silver-cationized molecules. Rosin esters and modified rosin esters in 22 rubber-based pressure sensitive adhesives and a paper-cement were analyzed. Glyceryl rosinate, glyceryl disproportionated rosinate, pentaerythrityl rosinate and pentaerythrityl hydrogenated rosinate were easily detected despite the fact that rubber-based adhesives are complex mixtures of elastomers, tackifiers, antioxidants and other additives. The detection limit of this method was studied and 2% of glyceryl rosinate in a rubber-based pressure sensitive adhesive was detected. It has been proved that MALDI-TOF-MS is a useful analytical method to analyze rosin and modified rosin esters in adhesives.  相似文献   
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Forensic databasing laboratories routinely analyze blood or buccal cell samples deposited on FTA® paper. Prior to PCR amplification of the STRs, the FTA® samples must undergo multi-step sample purification protocols to remove the PCR inhibitors present within the sample and from the FTA® paper. The multi-step sample purification protocols are laborious, time-consuming and increase the potential for sample cross-contamination.To eliminate the need for DNA purification, we conducted studies to optimize the PCR buffer and thermal cycling parameters to allow for direct amplification of STRs from blood or buccal samples on FTA® paper. We evaluated the effect of various factors on the DNA profile including: FTA® disc size, blood sample load variation, and buffer formulation. The new STR assay enables the direct amplification of DNA from single source samples on FTA® discs without sample purification. The new STR assay improves the workflow by eliminating tedious steps and minimizing sample handling. Furthermore, the new STR assay reduces cost by eliminating the need for purification reagents and expensive robots.  相似文献   
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