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The aim of this study was to investigate markers of serotonin and immune function in suicidal patients. Cytotoxic activity of natural killer cells (NK) and CD16 lymphocytes were studied in 28 suicide attempters and 26 healthy controls, and related in patients to 5-hydroxyindoleacetic acid (5-HIAA) in cerebrospinal fluid (CSF). Patients with CSF 5-HIAA below the median had significantly lower NK cell activity than other patients. CD16 cell frequency was significantly lower in patients than in controls, and patients also tended to have lower NK cell cytotoxicity than healthy controls. There were no statistically significant correlations between 4-hydroxy-3methoxyphenyl glycol (HMPG), homovanillic acid (HVA), CSF cortisol and NK cell activity. The results support the hypothesis of compromised immune function in suicidal patients with evidence of disordered serotonin function.  相似文献   
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BACKGROUND: Systemic sclerosis (SSc) is a connective tissue disorder of unknown etiology characterized by fibrosis of the skin and visceral organs, in which the heart is frequently (40-70% of patients) and severely involved. Pulmonary hypertension affects 10-15% of patients with SSc and is one of the most important complications adversely influencing their survival. CASE REPORT: The case report presents a 59-year-old male patient with advanced systemic sclerosis whose initial examination revealed pulmonary hypertension, rhythm and atrioventricular conduction disturbances, and elevated level of NT-proBNP. After six months the patient deteriorated; an increase in NT-proBNP level and progression of pulmonary hypertension were observed. CONCLUSIONS: The described case is followed by a discussion of cardiovascular involvement in systemic sclerosis and emphasizes that heart involvement in SSc may have very serious clinical implications.  相似文献   
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Summary We examined 81 men exposed for a long time to carbon disulphide (CS2) and tested the possible electrocardiographic (ECG) changes of ischemic heart disease (I.H.D.). The subjects were examined twice in two years. In order to make the ECG evaluation more objective, the Minnesota Code was applied. Two obligatory ECG examinations and only one submaximal effort test were carried out. For comparative evaluation, the control group was examined once. We proved that, in spite of the accepted opinion concerning the atheromatous action of CS2, this compound does not cause ECG symptoms of I.H.D. in a higher percentage of exposed persons. It also does not cause any significant increase in I.H.D. symptoms in dynamic ECG observations.  相似文献   
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Spatial adjacency of stimulus source and response site has been proven important for learning of simple behavioural tasks, including auditory quality and location discrimination. We investigated effect of sound source position (adjacent or not adjacent to manipulanda) on learning and performance of a complex auditory recognition memory task. Spatial adjacency of stimuli and manipulanda improved learning of a simple auditory directional task, which was an intermediate stage of training. In contrast, no improvement of learning and performance of the recognition task was found.  相似文献   
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Maf1p is a negative effector of RNA polymerase III in yeast. The maf1-delta mutation caused an increase in the level of cellular tRNAs, but a decrease of translational readthrough at nonsense codons. Using the lacZ- luc dual gene reporter system, we detected an almost twofold diminution of UAA and UAG readthrough in maf1-delta compared with the parental strain. The maf1-delta mutation did not affect the rate of protein biosynthesis and growth at standard conditions, but resulted in temperature-sensitive growth on non-fermentable carbon sources. We examined the correlation of the temperature sensitive and antisuppression phenotypes of maf1- Delta using a colour phenotype assay in the ade2-1 SUP11 strain. Antisuppression, but not the temperature-sensitive growth defect, was compensated either by increased dosage of SUP11or by [PSI(+)], the prion form of the translation termination factor Sup35p. Summarizing, the elevated tRNA levels in maf1- Delta increase translational fidelity and, independently, affect growth under special conditions.  相似文献   
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The copolymerizations of acrylonitrile, methacrylonitrile, methyl acrylate, methyl methacrylate, methyl vinyl ketone, acroleine, and acrylic acid with butadiene were carried out in the presence of the Lewis acids ZnCl2, BF3, CH3AlCl2, C2H5AlCl2, AlCl3, SnCl4, and TiCl4 and also in the absence of catalyst. Relative reactivity orders of the above polar vinyl monomers in the copolymerization and 1,4-cycloaddition reactions with butadiene and also the catalytic activity orders of Lewis acids in these reactions were determined. The composition of the polymers formed and the structure of their butadiene units were also determined. The mechanism of the copolymerization and 1,4-cycloaddition of the polar vinyl monomers with butadiene in the presence of Lewis acids is discussed.  相似文献   
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