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BACKGROUND: This study examined patients with a first-episode of affective psychosis during acute and compensated states in order to determine whether changes in attentional functioning over time were accompanied by changes in the severity of psychotic or affective symptoms. METHODS: Attentional performance was measured in patients (n = 27) using the degraded-stimulus continuous Performance Test (CPT) and symptoms were assessed at the time of index hospitalization, and 2 months after discharge. A comparison group of normal volunteers (n = 31) also performed the CPT two months apart. RESULTS: Patients performed significantly worse than controls at the initial testing but not at follow-up. The improvement in attentional performance significantly correlated with decreased severity of manic symptoms. CONCLUSIONS: Results suggest attentional dysfunction is a state-dependent characteristic of mania, and may provide an additional measure of clinical improvement following treatment.  相似文献   
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The electrochemical oxidation and reduction of hydrogen and chlorine in hydrochloric acid has been investigated on graphite, ruthenized titanium and platinum electrodes. Both steady state and potentiostatic pulse methods were used. Cell studies were also carried out in cells with flow-by and flow-through chlorine electrodes. Results indicate that the electrode kinetics are fast and the electrolysis and fuel cell reactions can be carried out in the same cell with electric-to-electric efficiencies in excess of 75% at current densities of 300 mA cm–2. Mass transfer limitations at the chlorine electrode during discharge can be eliminated by cell pressurization and the use of flow-through electrodes.This study was carried out under the auspices of the US Department of Energy.in the summers of 1976 and 1977  相似文献   
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There is an urgent need for new drugs for the treatment of tropical parasitic diseases such as human African trypanosomiasis, which is caused by Trypanosoma brucei. The enzyme trypanothione reductase (TryR) is a potential drug target within these organisms. Herein we report the screening of a 62 000 compound library against T. brucei TryR. Further work was undertaken to optimise potency and selectivity of two novel‐compound series arising from the enzymatic and whole parasite screens and mammalian cell counterscreens. Both of these series, containing either a quinoline or pyrimidinopyrazine scaffold, yielded low micromolar inhibitors of the enzyme and growth of the parasite. The challenges of inhibiting TryR with druglike molecules is discussed.  相似文献   
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The small-signal gain and saturation intensity in a waveguide CO2laser are determined by means of a least squares curve-fitting technique. The method allows the simultaneous estimation of the two parameters from an arbitrary number of data points relating power output to the incidence angle of an internal coupling plate.  相似文献   
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The MIS department has coordinated the acquisition and distribution of PCs and software for many business purposes but has often overlooked word processing, a major office application. MIS may prefer to leave it where it is — on rapidly aging dedicated word processors. Consolidating word processing with other applications, however, not only results in cost savings but can also increase the flexibility of the organization's PC investment and enhance the productivity of both WP and non-WP users. This article presents a case for transferring word processing to PCs and highlights its advantages.  相似文献   
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Reliability of adult retrospective recall of lifetime tobacco use.   总被引:1,自引:0,他引:1  
Retrospective assessment of tobacco use underlies much of the data collected in epidemiological and genetic epidemiological research. Although individuals are asked to report lifetime tobacco use for periods spanning months to decades, the test-retest reliability intervals of the instruments often span only a few weeks to several months. The present analyses examined the test-retest reliability of retrospective tobacco use measures, including details of first use, circumstances of first use, and initial subjective reactions. The questions were part of the Lifetime Tobacco Use Questionnaire (LTUQ), a Web-based questionnaire designed to assess use of most forms of tobacco or nicotine retrospectively across the lifespan. A convenience sample of 236 men and women with history of tobacco use (Time 1 mean age, 44.9 years; 74.2% females; 75.1% regular monthly tobacco use) responded verifiably to invitations to self-administer the LTUQ two times, 2 years apart. Test-retest reliability analyses reflected high reliability for salient tobacco-use questions. Acceptable levels of reliability were observed for initial subjective reactions to smoking, if the scaled response options were dichotomized. Few differences in the reliability of recall were apparent between sexes and between age groups. These results indicate that recall of important tobacco use information can form a reliable basis for research.  相似文献   
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The present study investigated the tolerability, safety profile, and anti-obsessional efficacy of sertraline, a selective serotonin reuptake inhibitor, during long-term treatment of patients with obsessive-compulsive disorder (OCD). Fifty-nine OCD patients who had completed a 1 year double-blind, fixed dose study comparing sertraline and placebo subsequently entered a 1-year open extension. Among the 51 patients who had been treated with sertraline during the double-blind phase, the mean total duration of sertraline treatment was 690 days. Only treatment responders who completed the 52-week double-blind treatment phase were permitted to enter the open extension. The higher rate (p < 0.02) of sertraline patients (51 out of 241) than of placebo patients (eight out of 84), who responded to treatment and entered the open-label phase is therefore consistent with the greater mean improvement observed in the sertraline group during double-blind treatment. Placebo responders differed from sertraline responders in that they were less impaired at baseline of the double-blind study [Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) of 18.5 versus 23.4] and they exhibited less improvement during double-blind treatment (-6.1 versus -11.4). In the open-label phase all patients received sertraline at a starting dose of 50 mg once a day, titrated in 50 mg increments to a maximum dose of 200 mg according to clinical response. At end-point the mean Y-BOCS score for all patients decreased by a further 3.6 points. Patients previously treated with placebo showed greater improvement after being switched to sertraline than those who received continued sertraline treatment. Patients who completed the study and received 2 full years of sertraline treatment (n = 38) exhibited a mean improvement of 15.6 points using the Y-BOCS. Sertraline was well tolerated during both the double-blind phase and the open extension, and the incidence of adverse experiences was generally reduced during the second year of treatment. Three patients discontinued open treatment because of adverse experiences. Long-term sertraline treatment did not appear to be associated with the emergence, increased incidence, or increased severity of adverse experiences or clinically significant abnormalities in laboratory tests, vital signs, or the electrocardiogram. The study supports the long-term safety and tolerability of sertraline over a 2-year treatment course and the sustained efficacy of sertraline in patients with OCD.  相似文献   
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