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991.
A self-regulation model was applied for predicting alcohol problem recognition. With the rate of others' alcohol use serving as a standard, problem recognition was predicted to increase the more one perceived one's drinking rate to be above others' use. Within the context of a classroom-administered survey, 707 nonabstaining undergraduates reported their drinking rates and estimated other students' drinking rates for annual drinking frequency, average weekly drinking quantity, and recent heavy drinking frequency. The independent roles of one's own and others' drinking rates, as well as the discrepancy between these two rates in predicting problem recognition, were examined. Findings were consistent with a self-regulation account. Across measures, only own drinking rate independently predicted problem recognition. Others' drinking rate interacted with own drinking rate in predicting problem recognition on the quantity measure. Specifically, the more heavy drinkers perceived their own quantity to be above others', the higher their problem recognition. Finally, gender effects were observed. Although men reported higher problem recognition than women, women reflected more on their drinking rates for problem recognition. 相似文献
992.
Killen JD Robinson TN Ammerman S Hayward C Rogers J Samuels D Schatzberg AF 《Addictive behaviors》2004,29(8):1517-1526
This is the first study to examine the prevalence and effects of major depression (MDD) in a sample of adolescent smokers (N = 211) undergoing treatment for nicotine dependence. We assessed MDD at baseline and end of treatment with the mood disorders portion of the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV). Eleven percent of participants reported a history of MDD (6% of males and 21% of females). Study variables did not distinguish those with and without a history of MDD. End of treatment abstinence rates and relapse rates were similar in both groups. Two participants (1%), both female, experienced onset of MDD during the treatment. The findings provide further evidence that MDD is a comparatively common disorder among children and adolescents and that clinicians should monitor and be prepared to respond to depression that may emerge during the treatment of nicotine-dependent adolescents. 相似文献
993.
Data from a longitudinal cohort study were used to directly compare the concurrent and predictive validity of four univariate typologic approaches with a multivariate approach in subtyping drug dependence. The four univariate typologies were based upon: (a) age-of-onset of drug abuse/dependence, (b) presence of drug abuse in first-degree relatives, (c) presence of antisocial personality disorder, and (d) sex. The multivariate typologic approach was based on indices of vulnerability, chronicity, consequences, and psychopathology, yielding the Type A/B dichotomy first demonstrated in alcohol dependence. Subtypes generated from the univariate typologies were then each compared with the multivariate typology on measures of concurrent and predictive validity, and the strength of association was compared statistically. There was evidence of significantly greater concurrent validity of the Type A/B typology compared with the univariate typologies across all the domains of validation (risk, substance use, psychopathology, personality, and overall functioning). The multivariate typology also fared better than the univariate ones in all three domains on which predictive validity was evaluated: substance use, psychopathology, and overall functioning, as well as the degree of change in several composite scores (drug, medical, legal, and psychiatric) and the global psychiatric symptom index. This direct method of comparison seemed to demonstrate the superior validity of the multivariate cluster-analytic approach over the univariate approaches to classifying subjects with drug dependence. 相似文献
994.
Rats undergoing extinction of lever-pressing for food after the attenuation of an external feedback for this behavior, exhibit excessive lever-pressing unaccompanied by an attempt to collect a reward, which may be analogous to the excessive and unreasonable behavior seen in obsessive-compulsive disorder (OCD). Given that one of the most salient features of OCD is its selective response to treatment with serotonin re-uptake inhibitors (SRIs), the present study compared the effects of the SRIs paroxetine and fluvoxamine on compulsive lever-pressing, with those of the tricyclic antidepressant, desipramine, and the benzodiazepine, diazepam, which are not effective in the treatment of OCD. Paroxetine (1-15 mg/kg) and fluvoxamine (10-20 mg/kg) dose-dependently reduced the number of compulsive lever-presses and the number of lever-presses followed by an attempt to collect a reward; desipramine (5-15 mg/kg) dose-dependently reduced only the number of lever-presses followed by an attempt to collect a reward; diazepam (2-10 mg/kg) did not affect either type of lever-pressing, except for the highest dose (10 mg/kg), which almost completely abolished lever-press responding. When administered in an extinction session not preceded by signal attenuation, paroxetine, fluvoxamine and desipramine affected only the number of lever-presses followed by an attempt to collect a reward, whereas diazepam (4-8 mg/kg) decreased both types of lever-presses. The present findings strengthen the suggestion that compulsive lever-pressing may serve to model compulsive behavior in OCD, and lends the model predictive validity. 相似文献
995.
996.
Wollstein G Schuman JS Price LL Aydin A Beaton SA Stark PC Fujimoto JG Ishikawa H 《American journal of ophthalmology》2004,138(2):218-225
PURPOSE: To investigate the structure-function relationship between optical coherence tomography (OCT) macular retinal and peripapillary nerve fiber layer (NFL) thickness and automated visual field (VF) findings. DESIGN: Cross-sectional observational study. METHODS: Retrospective institutional study where 150 consecutive eyes (101 subjects) from a glaucoma service were included. All the participants had full ophthalmic evaluation, VF testing and prototype OCT scanning at the same visit. Orthogonal OCT macular analysis was obtained to maximize the sampling of the area of interest. Pearson age-adjusted correlation was determined between macular retinal thickness and peripapillary NFL thickness. Area under the receiver operator characteristics (AROC) curves for the association between macular retinal thickness and peripapillary NFL thickness and VF findings were calculated in a subgroup of eyes without VF defect and eyes with VF defect confined to one hemifield. RESULTS: The correlation between macular retinal and peripapillary NFL measurements ranged between r =.27 to.54 for quadrants,.44 to.55 for hemiretina, and.52 for the overall mean. Areas under the receiver operator characteristics for macular thickness were higher in areas corresponding to the VF defect location than the noncorresponding locations. Areas under the receiver operator characteristics for peripapillary NFL thickness were higher than for the macular retinal thickness. Including both macular retinal thickness and peripapillary NFL thickness measurements in the logistic regression model yielded AROCs (range:.69 -.77) similar to those found for the peripapillary NFL alone. CONCLUSION: Macular retinal thickness, as measured by OCT, was capable of detecting glaucomatous damage and corresponded with peripapillary NFL thickness; however, peripapillary NFL thickness had higher sensitivity and specificity for the detection of VF abnormalities. 相似文献
997.
998.
999.
Hazzan D Fishman E Heller E Chapman M Bauer JJ 《The Mount Sinai journal of medicine, New York》2004,71(5):351-354
Liver abscess is a rare complication of Crohn's disease and must be considered part of the differential diagnosis. We present three case reports and a review of the literature. The incidence of liver abscess is higher in patients with Crohn's disease than in the general population. Since Crohn's disease patients who present with a liver abscess generally do not respond to medical management alone, surgical or percutaneous drainage of the abscess is necessary. 相似文献
1000.
Zhu G Lipsky RH Xu K Ali S Hyde T Kleinman J Akhtar LA Mash DC Goldman D 《Psychopharmacology》2004,177(1-2):178-184
Rationale A common polymorphism, Val158Met, alters catechol-O-methyltransferase (COMT) enzyme activity and has been linked to psychiatric phenotypes. Bray et al. (2003) reported that COMT is subject to differential allele expression in brain, finding modest (13–22%) underexpression of a haplotype containing Val158. However, disparate findings by another group who used the same method, but in lymphoblasts, raise the issues of tissue specificity, magnitude of differential expression, and identity of loci altering expression.Objectives We measured COMT allele expression ratios in heterozygous human lymphoblast cell lines and brains.Methods Using transcribed single nucleotide polymorphisms as endogenous reporters, we developed an RT-coupled 5 nuclease assay for allele expression ratios and applied it to 63 COMT rs4818(C>G) heterozygotes and 68 Val158Met [rs4680(G>A)] heterozygotes.Results For rs4818(C>G), the C allele was overexpressed relative to the G allele in 18 of 27 lymphoblast lines and 23 of 36 brains. For Val158Met, Met158 was overexpressed relative to Val158 in all (29 of 29) lymphoblast lines and all (39 of 39) brains. Each of the 22 rs4818 heterozygotes without differential allele expression was a Val158/Val158 homozygote. The Met158 allele was overexpressed by 65–77% when compared with Val158 in lymphoblasts and brain. Haplotype augmented ability to predict expression in brain only. However, the expression of the Val158 allele on the high-expressing haplotype was only 19% higher than Val158 alleles on the other haplotype background.Conclusions
COMT alleles are differentially expressed. The Met158 allele predicts higher mRNA expression in both brain and lymphoblasts. As exemplified here, the RT-coupled 5 nuclease assay is a reliable method for the quantitative evaluation of cis-acting regulatory effects. 相似文献