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OBJECTIVE: Heavy alcohol use among college students represents a public health problem on American college campuses. A promising area for combating this problem is identifying protective behavioral strategies that may reduce consumption and its resulting negative consequences among students who do choose to use alcohol. The purpose of this study was to develop and conduct initial psychometric analyses on a new scale, which we named the Protective Behavioral Strategies Survey. METHOD: Data were collected on 437 undergraduate students, who volunteered to participate in the study, at a large, public university in the northeast region of the United States. RESULTS: Results from an exploratory factor analysis yielded three theoretically meaningful factors that we labeled Limiting/Stopping Drinking, Manner of Drinking and Serious Harm Reduction. The three factors were, as a group, significantly associated with both alcohol consumption and alcohol-related problems, but the strongest unique relationship existed between Manner of Drinking and the outcome variables. CONCLUSIONS: Protective behavioral strategies seem to be a measurable construct that are related to alcohol consumption and alcohol-related problems, and thus may be a useful component of intervention and prevention programs with college students.  相似文献   
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In a series of 36 patients with acute schizophrenia flupenthixol dosage was blindly adjusted to give a fixed level of sedation. Patients were than randomly allocated to procyclidine or placebo. The patients receiving procyclidine experienced more positive schizophrenic symptoms and less severe extrapyramidal features by comparison with placebo patients. Blood levels of prolactin and flupenthixol estimated by radioimmunoassay were not significantly changed by the addition of procyclidine. Flupenthixol dosage and levels and prolactin levels were significantly related. There was no significant association between clinical and laboratory measures, with the exception that a curvilinear (inverted U) relationship was demonstrated between flupenthixol levels and antipsychotic and extrapyramidal effects. This relationship may be due to the fact that, in a study of this design, patients resistant to the effects of neuroleptic medication are likely to be given the highest doses. The findings support earlier claims that anticholinergic medication has adverse effects on schizophrenic symptoms.  相似文献   
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OBJECTIVE: An increase in white-matter lesions has been previously described in older subjects with depression. The authors investigated whether the regional location varied between depressed and normal subjects and determined the relationship of magnetic resonance (MR) signal hyperintensities to known clinical risk factors for vascular disease. METHODS: Authors used automated image-processing software to determine volumes of signal hyperintensities from MR brain scans of older people with depression (N=29; mean age: 76 years) and normal subjects of similar age (N=32). RESULTS: Overall, subjects with depression had a significantly greater frontal-lobe white-matter lesion volume than normal subjects (0.35% versus 0.22%). However, after excluding subjects with hypertension, diabetes, or ischemic heart disease (leaving 14 depressed and 15 normal subjects), we found even greater differences between groups, with a larger volume of MR signal hyperintensities in the frontal region of the depressed group, but no difference in the basal ganglia or parietal and occipital lobes. CONCLUSION: The results support the "vascular depression" hypothesis and suggest that those with depression but without traditional vascular risk factors may be much more susceptible to cerebrovascular disease than normal subjects. The mechanisms for this increased susceptibility remain to be determined.  相似文献   
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Objectives:  The initial design of the BALANCE (Bipolar Affective disorder: Lithium / ANtiConvulsant Comparative Evaluation) Trial of maintenance treatment for bipolar disorder was based on the experience of previous trials in bipolar disorder and psychiatry and on the methods developed for large randomized trials in other areas of medicine. This report describes the adaptations to the initial design and trial procedures following the initial phases of the study. The rationale for the trial and full protocol have been published elsewhere.
Methods:  A pilot study and start-up phase were used to check the tolerability of the interventions, refine the trial design and develop trial procedures that are acceptable to both clinicians and patients.
Results:  Changes to the procedures included: the dropping of masking of allocated treatment from clinicians and participants; introduction of the use of postal delivery to supply medication; and dispensing with the proposed schedule of regular follow up appointments. In addition, support was made available to participating psychiatrists who often had limited experience of participating in randomized trials.
Conclusions:  Pilot studies and start-up phases are essential to refine clinical trial design and allow development of procedures that are both methodologically rigorous and flexible and robust enough to promote recruitment and follow up. BALANCE is now actively recruiting in the UK and USA.  相似文献   
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OBJECTIVE: Few studies have examined pathological changes in serotonergic neurons in depression, particularly in elderly patients and in elderly patients in which depression occurs in dementia. The authors hypothesized that greater neurofibrillary pathology and fewer serotonergic neurons would be found in the dorsal raphe nuclei in depressed elderly subjects, compared with nondepressed elderly subjects, and in Alzheimer's disease patients with depression, compared to Alzheimer's disease patients without depression. METHOD: In a postmortem study, immunocytochemistry and two-dimensional image analysis were used to measure neuronal density and neuritic pathology in serotonergic neurons in the dorsal raphe nuclei of elderly subjects with primary major depression (N=14), elderly Alzheimer's disease patients with (N=8) and without (N=7) comorbid depression, and nondepressed elderly comparison subjects (N=10). RESULTS: No differences in neuritic pathology or neuronal density were found between the subjects with primary major depression and the nondepressed comparison subjects. The Alzheimer's disease subjects showed markedly fewer serotonergic neurons and associated higher levels of neuritic pathology, compared with the subjects with primary depression and the nondepressed comparison subjects, but the Alzheimer's disease subjects with comorbid major depression did not differ from the Alzheimer's disease subjects without depression on these measures. CONCLUSIONS: The study found no evidence of a loss of serotonergic neurons or of neuritic pathology in the dorsal raphe nuclei in older people with depression, with or without comorbid Alzheimer's disease. These findings suggest that if serotonergic dysfunction occurs in older depressed subjects, it is not due to neuronal loss in the brainstem. Pathophysiological changes may lie elsewhere, such as in the frontal-subcortical circuits.  相似文献   
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Advanced glycation end products (AGE), growth factors, and nitric oxide contribute to alterations of the peritoneum during peritoneal dialysis (PD). These mediators are also involved in chronic uremia, a condition associated with increased permeability of serosal membranes. It is unknown whether chronic uremia per se modifies the peritoneum before PD initiation. A rat model of subtotal nephrectomy was used to measure peritoneal permeability after 3, 6, and 9 wk, in parallel with peritoneal nitric oxide synthase (NOS) isoform expression and activity and structural changes. Uremic rats were characterized by a higher peritoneal permeability for small solutes and an increased NOS activity due to the up-regulation of endothelial and neuronal NOS. The permeability changes and increased NOS activities correlated with the degree of renal failure. Focal areas of vascular proliferation and fibrosis were detected in uremic rats, in relation with a transient up-regulation of vascular endothelial growth factor and basic fibroblast growth factor, as well as vascular deposits of the AGE carboxymethyllysine and pentosidine. Correction of anemia with erythropoietin did not prevent the permeability or structural changes in uremic rats. Thus, in this rat model, uremia induces permeability and structural changes in the peritoneum, in parallel with AGE deposits and up-regulation of specific NOS isoforms and growth factors. These data suggest an independent contribution of uremia in the peritoneal changes during PD and offer a paradigm to better understand the modifications of serosal membranes in uremia.  相似文献   
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