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There is a need for noninvasive methods to detect liver steatosis, which can be a factor of liver fibrosis progression. This work aims to evaluate a novel ultrasonic controlled attenuation parameter (CAP) devised to target, specifically, liver steatosis using a sophisticated process based on vibration control transient elastography (VCTE™). CAP was first validated as an estimate of ultrasonic attenuation at 3.5 MHz using Field II simulations and tissue-mimicking phantoms. Performance of the CAP was then appraised on 115 patients, taking the histological grade of steatosis as reference. CAP was significantly correlated to steatosis (Spearman ρ = 0.81, p < 10−16). Area under receiver operative characteristic (ROC) curve (AUC) was equal to 0.91 and 0.95 for the detection of more than 10% and 33% of steatosis, respectively. Furthermore, results show that CAP can efficiently separate several steatosis grades. These promising results suggest that CAP is a noninvasive, immediate, objective and efficient method to detect and quantify steatosis. (E-mail: magali.sasso@echosens.com)  相似文献   
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SETTING: Burkina Faso, West Africa. OBJECTIVE: 1) To determine the trend of sputum smear conversion rates at the 2-month follow-up of new smear-positive tuberculosis (TB) patients; and 2) to compare conversion rates in cured TB patients and treatment failures. DESIGN: Retrospective cohort study based on TB registers from all 80 diagnostic and treatment centres from 1995 to 2003. The conversion rate was defined as the number of negative results divided by the number of smear-positive patients for whom the 2-month follow-up examination was completed. RESULTS: The 2-month follow-up completion rate was 92.1%; it increased from 86.3% in 1996 to 94.3% in 2003. The conversion rate was 82.9%, increasing from 76.3% in 1995 to 87.9% in 1997 and falling to 80.3% in 2003. The cure rate was higher among patients who were smear-negative at the 2-month follow-up (77.3%) CONCLUSION: The conversion rate was satisfying, but had declined since 1997, which may be a matter of concern. This could be due to patient characteristics such as associated conditions (human immunodeficiency virus, malnutrition) or to drug management (ineffective administration of drugs even under directly observed treatment, insufficient dosages, resistance). Thorough research is needed to elucidate this negative trend.  相似文献   
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Serum HBeAg levels and HBe-seroconversion were investigated in patients with chronic HBeAg-positive hepatitis who were randomized to receive either alpha lymphoblastoid interferon (5 megaunits subcutaneously daily for 16 weeks) plus acyclovir (2 g intravenously daily during weeks 1 and 2 and weeks 9 and 10) (n = 49) or no treatment (n = 48). HBeAg levels in serial dilutions of patient serum were assessed quantitatively by radioimmunoassay and compared with the values found for negative control serum. One year after the start of therapy 44 treated patients and 43 control patients were available for follow-up. A complete response (HBe-seroconversion) occurred in 11 treated patients (25%) and six controls (14%) (difference: 11%, 95% CI-5-28%). A partial response (HBeAg less than 50% of initial level) was found significantly more often for treated patients (n = 13, 30%) than for controls (n = 2, 5%) (difference: 25%, 95% CI 10-40%). During acyclovir-interferon combination therapy the decrease in HBeAg level was similar to that achieved during therapy with interferon alone. We conclude that acyclovir does not enhance the effect of interferon on serum HBeAg levels. Since HBeAg levels continue to decline during interferon treatment and rebound thereafter to pretreatment levels, prolongation of therapy may yield a higher response rate.  相似文献   
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