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411.
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Organic solvent abuse typically involves sniffing organic solvents to experience the mind-altering conditions they induce. In Republic of Korea, organic solvent abuse is a serious social problem, especially among teenagers. Several studies have addressed the effects of organic solvent abuse on mind and body, but there are no simple methods by which such abuse can be positively identified. In this report, we describe a method for analyzing toluene metabolites (toluene is the main ingredient of glue) in glue-sniffers' urine using (1)H NMR spectroscopy. Toluene is a commonly used solvent in the rubber, paint, plastics, leather, printing, and chemical industries. Inhaled toluene is metabolized to hippuric acid in the liver and excreted in the urine. Hippuric acid is known as a good biomarker for biological monitoring of toluene exposure. We have scanned hippuric acid and other toluene metabolites by NMR spectroscopy and performed statistical multivariate analysis of the data. Based on this analysis, we sought to determine parameters by which glue-sniffing (toluene inhalation) behavior may be verified. We also demonstrate the use of a pattern recognition method for accurate and efficient analysis of NMR data. In comparison to conventional methods, such as mass spectroscopy coupled with liquid chromatography or gas chromatography, nuclear magnetic resonance spectroscopy has several advantages, including simple sample preparation, non-destructive sampling, accuracy, short acquisition time, and reproducibility in the determination of urinary hippuric acid.  相似文献   
413.
Although the acculturation gap generally has been associated with poor mental health outcomes among Asian American children, some studies have failed to find a significant relationship between the gap and distress. Using two different methods of operationalizing the gap between mothers and their children, the current study addressed this tension in the literature by testing the following hypotheses in a sample of Korean American families. It was hypothesized that mother–adolescent discrepancies in acculturation and enculturation levels would be associated with youth internalizing and externalizing symptoms and that parent–adolescent communication would moderate the gap–distress relationship. Multi-informant questionnaires were administered to 77 Korean American mother–adolescent dyads from the Midwest. Surprisingly, results indicated that consonance in low levels of mother–adolescent enculturation was associated with the highest levels of externalizing symptoms (interaction term method). Adolescents’ perception of communication with their fathers significantly moderated the relationship between the enculturation gap and internalizing symptoms, such that in dyads with a greater enculturation gap, less perceived open communication with fathers was associated with more internalizing symptoms (difference score method). Clinically, the findings indicate a potential target (i.e., parent–adolescent communication) for treatment programs that aim to improve family relations and youth adjustment in immigrant families.  相似文献   
414.
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