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BACKGROUND: Despite their important role in cognitive function, the value of B vitamin supplementation is unknown. A systematic review of the effect of pyridoxine hydrochloride (hereinafter "vitamin B(6)"), cyanocobalamin or hydroxycobalamin (hereinafter "vitamin B(12)"), and folic acid supplementation on cognitive function was performed. METHODS: Literature search conducted in MEDLINE with supplemental articles from reviews and domain experts. We included English language randomized controlled trials of vitamins B(6) and/or B(12) and/or folic acid supplementation with cognitive function outcomes. RESULTS: Fourteen trials met our criteria; most were of low quality and limited applicability. Approximately 50 different cognitive function tests were assessed. Three trials of vitamin B(6) and 6 of vitamin B(12) found no effect overall in a variety of doses, routes of administration, and populations. One of 3 trials of folic acid found a benefit in cognitive function in people with cognitive impairment and low baseline serum folate levels. Six trials of combinations of the B vitamins all concluded that the interventions had no effect on cognitive function. Among 3 trials, those in the placebo arm had greater improvements in a small number of cognitive tests than participants receiving either folic acid or combination B-vitamin supplements. The evidence was limited by a sparsity of studies, small sample size, heterogeneity in outcomes, and a lack of studies that evaluated symptoms or clinical outcomes. CONCLUSION: The evidence does not yet provide adequate evidence of an effect of vitamin B(6) or B(12) or folic acid supplementation, alone or in combination, on cognitive function testing in people with either normal or impaired cognitive function.  相似文献   
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In the majority (80%) of patients with acute pancreatitis, the disease is self limiting and, after a few days of withholding feeding and intravenous administration of fluids, patients can again be normally fed orally. In a small percentage of patients, the disease progresses to severe necrotic pancreatitis, with an intense systemic inflammatory response and often with multiple organ dysfunction syndrome. As mortality is high in patients with severe disease and as mortality and morbidity rates are directly related to the failure of establishing a positive nitrogen balance, it is assumed that feeding will improve survival in patients with severe disease. The aim of nutritional support is to cover the elevated metabolic demands as much as possible, without stimulating pancreatic secretion and maximizing self-digestion. The administration of either total parenteral nutrition or jejunal nutrition does not stimulate pancreatic secretion. Recently, a series of controlled clinical studies has been conducted in order to evaluate the effectiveness of enteral nutrition with jejunal administration of the nutritional solution. The results have shown that enteral nutrition, as compared to total parenteral nutrition, was cheaper, safer and more effective as regards the suppression of the immunoinflammatory response, the decrease of septic complications, the need for surgery for the management of the complications of acute pancreatitis and the reduction of the total hospitalization period. It did not seem to affect mortality or the rate of non-septic complications. In conclusion, enteral nutrition should be the preferred route of nutritional support in patients with acute pancreatitis.  相似文献   
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Background To investigate the relative frequency of localized mucosal swellings of the upper and lower labial mucosa, the clinical-pathological diagnosis agreement and whether patient’s age and gender and tumor’s site and size may raise the suspicion of neoplasm. Material and Methods Retrospective analysis was performed on upper or lower labial mucosal tumors, histopathologically diagnosed between 2009-2018. The diagnostic categories developmental/reactive tumors, benign and malignant neoplasms were associated with patient’s age and gender and tumor’s site and size; clinical-pathological diagnosis agreement was, also, evaluated. Results Overall, 1000 (95.7%) developmental/reactive tumors, 35 (3.3%) benign and 10 (1%) malignant neoplasms were found. Upper/lower lip tumor ratio was 0.14:1. The diagnostic category was significantly associated with age (p<0.0001), site (p<0.0001) and diameter (p<0.0001). Age ≥60 years, tumor’s location on the upper lip and diameter >1cm were independent predictors for neoplasms. Patients presenting 2 or 3 of these variables were 20.2 times (p < 0.0001) or 33.6 times (p <0.0001), respectively, more likely to have a neoplasm. Complete/partial agreement between clinical and pathological diagnosis was seen in 96.3% of the cases. Conclusions Most lip tumors involve the lower lip and are reactive, but upper lip tumors measuring >1cm in patients≥60 years have significantly higher probability to be neoplasms. Key words:Lip, tumor, neoplasm, carcinoma, cyst.  相似文献   
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Salmonella bacteraemia in a tertiary children's hospital   总被引:2,自引:0,他引:2  
A retrospective study was conducted between July 1990 and July 2002 to investigate the epidemiology, clinical characteristics, and the outcome of Salmonella bacteraemia in children. A total of 148 episodes of bacteraemia were identified in 144 children. The annual incidence ranged from 1.6 to 8.3 cases per 100,000 children < or = 14 y of age, and higher numbers of cases occurred in summer than in winter months. In 22 children the bacteraemia was caused by S. typhi and in 122 by S. non-typhi. S. enteritidis was the most common serotype isolated. Resistance to ampicillin was exhibited by 28.5% of Salmonella isolates, whereas all S. typhi isolates were susceptible to commonly used antibiotics. The mean age was 40.3 months (range 50 d to 14 y). Children with S. typhi bacteraemia were significantly older than children with S. non-typhi bacteraemia (7.8 vs 2.4 y, p < 0.01). 11 children were immunosuppressed. The immunosuppressed children had longer duration of fever, longer hospitalization stay, and higher relapse rates compared to normal children (p < 0.05). Four children developed complications and 1 died. Although the incidence of S. typhi bacteraemia is decreasing, the non-typhi species continue to cause significant morbidity in our geographical region.  相似文献   
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OBJECTIVE: To evaluate whether the C677T polymorphism of the methylenetetrahydofolate reductase (MTHFR) gene is consistently associated with hypertension in pregnancy. DESIGN: Meta-analysis of studies comparing women with and without hypertension in pregnancy for the C677T MTHFR polymorphism. METHODS: Studies were identified with MEDLINE and EMBASE searches complemented with perusal of bibliographies of retrieved articles and communication with investigators. Between-study heterogeneity was estimated and data were combined with random effects models. Sensitivity analyses examined the effect of population and disease characteristics. Bias diagnostics evaluated the evolution of the postulated genetic effect over time and the potential for publication bias. RESULTS: Across 23 comparisons (3169 hypertensive women, 3044 controls), having the T allele (TT or CT) increased the odds of hypertensive disease of pregnancy by 1.21-fold (95% confidence interval, 1.01-1.44), but there was large between-study heterogeneity (P = 0.003). The results were similar and heterogeneity persisted when sensitivity analyses were limited to studies of Caucasian populations, or those of patients with significant proteinuria. While patients with diastolic hypertension > or = 110 mmHg showed an odds ratio of 1.41 (95% confidence interval, 1.03-1.73), no association was seen in patients with less severe diastolic hypertension (odds ratio, 1.00; 95% confidence interval, 0.61-1.65). Early published studies tended to show stronger associations than the subsequent studies. CONCLUSIONS: While bias cannot be excluded, the meta-analysis suggests that the T allele may increase the risk of severe diastolic hypertension during pregnancy.  相似文献   
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Bone marrow angiogenesis has recently been implicated in the pathophysiology and course of various haematological malignancies. Little is known, however, about the significance of this phenomenon in hairy cell leukaemia (HCL). We evaluated various morphometric characteristics of microvessels, highlighted by means of anti-CD34 immunohistochemistry, in the bone marrow of 44 patients with typical HCL, before and after treatment with interferon-alpha (IFN-alpha). Overall, bone marrow from 103 HCL patients and 20 controls was examined. Microvessel density (MVD) and several size- and shape-related parameters were quantified in the region of most intense vascularization using image analysis. MVD, size-related parameters and the percentage of branching microvessels were higher in HCL than in controls. Likewise, perimeter counts were higher in partial/non-responders than in complete responders. Achievement of complete response was accompanied by smaller calibre microvessels. IFN-alpha induced a decrease in MVD and branching values in cases with diffuse marrow involvement. In univariate analysis, progression-free survival was adversely affected by MVD, branching and major axis length. Multivariate analysis indicated that MVD/branching independently affected progression-free survival and the likelihood of complete response. Our data suggest that the generation of bone marrow microvessels indicated an increased risk of progression and IFN-alpha treatment failure in HCL. Furthermore, the prognostic significance of angiogenesis requires the concomitant assessment of MVD and the complexity of the microvascular network.  相似文献   
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