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Background Previous reports have demonstrated contradicting results on the association between lichen planus and hepatitis. Objectives The aim of this study was to investigate the association between lichen planus and viral hepatitis. Methods Patients with lichen planus were compared with controls regarding the prevalence of viral hepatitis in a case‐control study using logistic multivariate regression models. The study was performed utilizing the medical database of Clalit Health Services. Results The study included 1557 lichen planus patients over the age of 20 years and 3115 age‐ and gender‐matched controls. The prevalence of hepatitis C in patients with lichen planus was higher than that in the control group (1.9%, 0.4% respectively, P < 0.001). In a multivariate analysis, lichen planus was associated with hepatitis C (OR 4.19, 95% CI 2.21; 7.93). The prevalence of hepatitis B in patients with lichen planus was similar to that in the control group (0.9%, 0.5% respectively, P = 0.12). A multivariate analysis revealed that lichen planus was not associated with hepatitis B (OR 1.69, 95% CI 0.82; 3.47). Conclusion Lichen planus is associated with hepatitis C but not with hepatitis B. Physicians who care for patients with lichen planus should consider screening patients with lichen planus for hepatitis C.  相似文献   
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Fluoride release from fluorine-carrying copolymers of vinylphosphonate induced by calcium apatite and tooth enamel has been investigated. Fluoride ions were determined potentiometrically in the study of calcium hydroxyapatite, and Auger spectroscopy was used to study the fluoride release to enamel. The adsorbed copolymer of vinylphosphonic acid and vinylphosphonyl thiofluoride was shown to release fluoride to calcium hydroxyapatite and to enamel. The oxygen analog has shown a similar behavior with calcium hydroxyapatite, but not with tooth enamel. The results suggest a potential application of such copolymers as caries preventive agents which combine the effects of polyphosphonates and of fluoride ions.  相似文献   
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Background: Powered brushes were first introduced commercially in the 1960s. A recent systematic review suggested the superiority of certain modes of powered over manual toothbrushing for plaque and gingivitis reduction. That review did not allow for direct comparison between different modes of powered toothbrush. Objectives: To compare different modes of powered toothbrushing against each other for plaque reduction and the health of the gingivae. Other factors to be assessed were calculus and stain removal, cost, dependability and adverse effects. Search strategy: The following databases were searched: Cochrane Oral Health Group’s Trials Register (to 26 July 2010); Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, Issue 3); MEDLINE via OVID (1950 to 26 July 2010); EMBASE via OVID (1980 to 26 July 2010); CINAHL via EBSCO (1982 to 26 July 2010). There were no language restrictions. Selection criteria: Trials were considered for inclusion with the following criteria: random allocation of participants; no compromised manual dexterity; unsupervised powered toothbrushing for at least four weeks. The primary outcomes were the plaque and gingivitis scores after powered toothbrush use during trial period. Data collection and analysis: Data extraction was performed independently and in duplicate. The authors of trials were contacted to provide missing data where possible. The effect measure for each meta‐analysis was the standardized mean difference (SMD) with 95% confidence intervals (CI) using the random‐effects model. Potential sources of heterogeneity were assessed. Main results: The review included data from 15 trials with 1015 participants. Due to the dearth of trials assessing the same mode of action, no definitive conclusions can be stated regarding the superiority of one mode of powered toothbrush over any other. Only minor and transient side effects were reported. Cost, dependability were not reported. Authors’ conclusions: Further trials of good quality are required to establish if any mode of action has superiority over the other modes of action for powered toothbrushes.  相似文献   
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Objective: Optimizing alveolar recruitment by alveolar recruitment strategy (ARS) and maintaining lung volume with adequate positive end‐expiratory pressure (PEEP) allow preventing ventilator‐induced lung injury (VILI). Knowing that PEEP has its most beneficial effects when dynamic compliance of respiratory system (Crs) is maximized, we hypothesize that the use of 8 cm H2O PEEP with ARS results in an increase in Crs and end‐expiratory lung volume (EELV) compared to 8 cm H2O PEEP without ARS and to zero PEEP in pediatric patients undergoing cardiac surgery for congenital heart disease. Methods: Twenty consecutive children were studied. Three different ventilation strategies were applied to each patient in the following order: 0 cm H2O PEEP, 8 cm H2O PEEP without an ARS, and 8 cm H2O PEEP with a standardized ARS. At the end of each ventilation strategy, Crs, EELV, and arterial blood gases were measured. Results: EELV, Crs, and PaO2/FiO2 ratio changed significantly (P < 0.001) with the application of 8 cm H2O + ARS. Mean PaCO2– PETCO2 difference between 0 PEEP and 8 cm H2O PEEP + ARS was also significant (P < 0.05). Conclusion: An alveolar recruitment strategy with relative high PEEP significantly improves Crs, oxygenation, PaCO2– PETCO2 difference, and EELV in pediatric patients undergoing cardiac surgery for congenital heart disease.  相似文献   
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