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The purpose of this study was to determine the performance characteristics of the Cozart microplate EIA for detecting opiates in oral fluid from patients in a drug misuse treatment program. Oral fluid samples were collected using the Cozart RapiScan Collection System from 216 donors who were receiving treatment for their addiction and were monitored for drug abuse. A further 40 oral fluid samples were collected from volunteer donors who were not drug users. The samples were analyzed in the laboratory by using the Cozart microplate EIA for opiates and confirmed using gas chromatography-mass spectrometry (GC-MS). The samples were stored frozen until analysis by GC-MS. The intra-assay precision for the Cozart microplate oral fluid EIA for opiates over 40 assays was 0.43% to 9.13% CV (within assay) and 2.9% to 9.1% CV (within day). A total of 109 samples were positive for various opiates. The Cozart microplate EIA for opiates in oral fluid, using a cut-off of 30 ng/ml morphine equivalents in neat oral fluid, had a sensitivity of 99.1 +/- 2.1% and a specificity of 94.4 +/- 2.2% versus GC-MS. A series of potential adulterants of oral fluid were evaluated and shown not to alter the outcome of the test result.  相似文献   
163.
The purpose of this study was to evaluate the efficiency of the Cozart RapiScan (CRS) drug test system for detecting opiates and cocaine in oral fluid. Oral fluid samples were collected using the Cozart RapiScan collection system from 358 donors who were receiving treatment for their addiction and were monitored for drug misuse. A further 103 oral fluid samples were collected from volunteer donors who were not drug users. The samples were analyzed in the laboratory using the two-panel Cozart RapiScan cartridge for opiates and cocaine and confirmed using gas chromatography-mass spectrometry (GC-MS). The samples were stored frozen at -20 degrees C until analysis by GC-MS. The overall accuracy of the CRS for both opiates and cocaine was 100%. Samples spiked at 50% above and below the cut-off consistently gave negative and positive results respectively. A total of 88 samples were positive for various opiates and 111 samples were positive for cocaine and/or its metabolites. The CRS for opiates and cocaine in oral fluid, using a cut-off of 30 ng/mL morphine or benzoylecgonine equivalents in neat oral fluid, had overall efficiencies of 98% and 99%, respectively, versus GC-MS. A series of potential adulterants of oral fluid were evaluated and shown not to alter the outcome of the test result.  相似文献   
164.
We have assessed the histological preservation of naturally degraded human hair shafts, and then assayed each for levels of amplifiable mitochondrial DNA and damage-associated DNA miscoding lesions. The results indicate that as sample histology is altered (i.e. as hairs degrade) levels of amplifiable mitochondrial DNA decrease, but no correlation is seen between histology and absolute levels of mitochondrial DNA miscoding lesions. Nevertheless, amplifiable mitochondrial DNA could be recovered across the complete range of the histological preservation spectrum. However, when template copy number is taken into consideration, a correlation of miscoding lesions with histology is again apparent. These relationships indicate that a potential route for the generation of misleading mitochondrial sequence data exists in samples of poor histology. Therefore, we argue that in the absence of molecular cloning, the histological screening of hair may be necessary in order to confirm the reliability of mitochondrial DNA sequences amplified from hair, and thus represents a useful tool in forensic mitochondrial DNA analyses.  相似文献   
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Waller D  Cooper M 《Time》2003,162(22):42, 44
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This article reports findings from an evaluation of an MSW child welfare training program focused on increasing retention of knowledgeable, competent and experienced child protective service workers. From qualitative data gathered as part of the process evaluation, we found the cohort effect to be the most salient factor participants experienced as contributing to their successful program completion and their 100% retention rate. Analysis of the cohort effect yielded five themes instrumental in participants' individual and collective success: mutual support, empowerment, belief in self and their finding of a home base which ultimately helped them to launch their professional selves.  相似文献   
170.
Using a leaked document trove containing 800 model bills, we analyze the American Legislative Exchange Council’s (ALEC) hidden corporate profit making in the prison–industrial complex. We find that ALEC seeks to expand the private prison industry in three ways: (1) promoting greater use of private prisons, goods, and services, (2) promoting greater use of prison labor, and (3) increasing the size of the prison population. ALEC’s efforts to increase the prison population by expanding definitions of existing crime, creating new crimes, enhancing enforcement of existing crimes, amending the trial process to increase the likelihood of incarceration, and lengthening prison sentences for crimes pose a threat to civil liberties. ALEC’s unorthodox policy approach exemplifies John Gaventa’s theory that powerful interests maintain their power by creating conditions in which citizens are not able to identify and advocate on behalf of their interests.  相似文献   
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