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41.
OBJECTIVES: To develop and validate a risk score predicting arrhythmias for patients with syncope remaining unexplained after emergency department (ED) noninvasive evaluation. METHODS: One cohort of 175 patients with unexplained syncope (Geneva, Switzerland) was used to develop and cross-validate the risk score; a second cohort of 269 similar patients (Pittsburgh, PA) was used to validate the system. Arrhythmias as a cause of syncope were diagnosed by cardiac monitoring or electrophysiologic testing. Data from the patient's history and 12-lead emergency electrocardiography (ECG) were used to identify predictors of arrhythmias. Logistic regression was used to identify predictors for the risk-score system. Risk-score performance was measured by comparing the proportions of patients with arrhythmias at various levels of the score and receiver operating characteristic (ROC) curves. RESULTS: The prevalence of arrhythmic syncope was 17% in the derivation cohort and 18% in the validation cohort. Predictors of arrhythmias were abnormal ECG (odds ratio [OR]: 8.1, 95% confidence interval [CI]=3.0 to 22.7), a history of congestive heart failure (OR: 5.3, 95% CI=1.9 to 15.0), and age older than 65 (OR: 5.4, 95% CI=1.1 to 26.0). In the derivation cohort, the risk of arrhythmias ranged from 0% (95% CI=0 to 6) in patients with no risk factors to 6% (95% CI=1 to 15) for patients with one risk factor, 41% (95% CI=26 to 57) for patients with two risk factors, and 60% (95% CI = 32 to 84) for those with three risk factors. In the validation cohort, these proportions varied from 2% (95% CI=0 to 7) with no risk factors to 17% (95% CI=10 to 27) with one risk factor, 35% (95% CI=24 to 46) with two risk factors, and 27% (95% CI=6 to 61) with three risk factors. Areas under the ROC curves ranged from 0.88 (95% CI=0.84 to 0.91) for the derivation cohort to 0.84 (95% CI=0.77 to 0.91) after cross-validation within the same cohort and 0.75 (95% CI=0.68 to 0.81) for the external validation cohort. CONCLUSIONS: In patients with unexplained syncope, a risk score based on clinical and ECG factors available in the ED identifies patients at risk for arrhythmias.  相似文献   
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PAQR3, also known as RKTG (Raf kinase trapping to Golgi), is a member of the progestin and adipoQ receptor (PAQR) family. The role of PAQR3 as a tumor suppressor has recently been established in different types of human cancer in which PAQR3 exerts its biological function through negative regulation of the oncogenic Raf/MEK/ERK signaling. Multiple studies have found that PAQR3 downregulation frequently occurs in human cancers and is very often associated with tumor progression and shortened patients’ survival. Moreover, restoring the expression of PAQR3 could induce apoptosis and inhibit proliferation and invasiveness of cancer cells. Downregulation of PAQR3 by oncogenic microRNAs has also been reported. In this review, we summarized current knowledge concerning the role of PAQR3 in tumor development. To our knowledge, this is the first review on the role of this novel tumor suppressor.  相似文献   
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The objective of this study was to assess the post-intervention effect of nicotine replacement therapy on reduction of cigarette consumption 1.5 years after the end of a 6-month treatment. Heavy smokers who had no intention of quitting smoking were recruited from the general population and were randomly assigned to a treatment of nicotine (choice of a 15-mg nicotine patch, a 4-mg nicotine gum, and/or a 10-mg nicotine inhaler, n = 265), matching placebo products (n = 269), or no intervention (n = 389). Products were sent to participants by mail. Education was limited to a booklet. Of 923 participants, 879 (95%) were followed 6 months after randomization and 846 (92%) were followed after 26 months. Mean baseline consumption was 30 cigarettes/day in all groups. After 6 months, cigarette consumption had decreased by a mean of 10.9 cigarettes/day in the nicotine group, 8.7 in the placebo group, and 4.9 among controls (P < or = 0.02 for all pairwise comparisons). After 26 months, compared with baseline, cigarette consumption had decreased by a mean of 9.8 cigarettes/day in the nicotine group, 7.7 in the placebo group, and 7.7 among controls (nicotine vs. placebo or control: P < or = 0.03). After 2 years, smoking cessation rates did not differ significantly among groups (nicotine 11.7%, placebo 9.3%, control, 10.0%; P = 0.6). Thus, a slight effect of nicotine replacement therapy on reduction of cigarette consumption was maintained 1.5 years after the end of the 6-month treatment, but the initially observed placebo effect was not maintained. Nicotine replacement therapy for smoking reduction had no deleterious impact on smoking cessation.  相似文献   
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AIMS: This study was initiated to test the hypothesis that metformin treatment leads to enhanced glucose disposal at ambient insulin concentrations. METHODS: Nineteen obese patients with impaired glucose tolerance (IGT) were treated with either metformin or placebo in a randomized, double-blind, placebo-controlled, cross-over study. Insulin secretion and insulin resistance were quantified using the homeostasis model assessment (HOMA) and insulin-stimulated glucose disposal were measured by determining the steady-state plasma glucose (SSPG). RESULTS: The average benefit of metformin was 0.6 mmol/l for glucose (95% confidence interval (CI) 0.2-0.9 P = 0.002), 2.8 pmol/l for insulin (95% CI 0.2-5.4, P = 0.019). Insulin resistance, as quantified by HOMA, was improved by 1.1 (95% CI 0.2-2.0, P = 0.004), without any change in insulin secretion. Basal and insulin-stimulated glucose oxidation were comparable in the placebo and metformin-treated groups at the end of each treatment period, as was the SSPG concentration. However, both systolic and diastolic blood pressures fell significantly following metformin administration as compared to treatment with placebo. CONCLUSIONS: These results indicate that metformin administration to patients with IGT is associated with enhanced glucose disposal at baseline insulin concentrations and a fall in blood pressure. In contrast, neither glucose oxidation nor glucose disposal were increased in association with metformin treatment under conditions of physiological hyperinsulinaemia.  相似文献   
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BACKGROUND: Many factors affect survival in haemodialysis (HD) patients. Our aim was to study whether quality of clinical care may affect survival in this population, when adjusted for demographic characteristics and co-morbidities. METHODS: We studied survival in 553 patients treated by chronic HD during March 2001 in 21 dialysis facilities in western Switzerland. Indicators of quality of care were established for anaemia control, calcium and phosphate product, serum albumin, pre-dialysis blood pressure (BP), type of vascular access and dialysis adequacy (spKt/V) and their baseline values were related to 3-year survival. The modified Charlson co-morbidity index (including age) and transplantation status were also considered as a predictor of survival. RESULTS: Three-year survival was obtained for 96% of the patients; 39% (211/541) of these patients had died. The 3-year survival was 50, 62 and 69%, respectively, in patients who had 0-2, 3 and >or=4 fulfilled indicators of quality of care (test for linear trend, P < 0.001). In a Cox multivariate analysis model, the absence of transplantation, a higher modified Charlson's score, decreased fulfilment of indicators of good clinical care and low pre-dialysis systolic BP were independent predictors of death. CONCLUSION: Good clinical care improves survival in HD patients, even after adjustment for availability of transplantation and co-morbidities.  相似文献   
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