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71.
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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Gradient-echo MR imaging: techniques and acronyms   总被引:3,自引:0,他引:3  
Elster  AD 《Radiology》1993,186(1):1
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Background: Previous reports have suggested the occurrence of cardiac conduction disorders and permanent pacemaker (PPM) requirement after transcatheter aortic valve implantation (TAVI). Based on a single‐center experience, we aim to assess the incidence of postprocedural conduction disorders, need for PPM, and its determinants after TAVI with a self‐expanding bioprosthesis. Methods: From August 2007 to October 2009, 32 consecutive patients underwent TAVI with the Medtronic CoreValve (MCV) System (Medtronic Inc., Minneapolis, MN, USA). Three patients paced at baseline and two cases of procedure‐related mortality were excluded. We analyzed the 12‐lead electrocardiogram at baseline, immediately after procedure and at discharge. Requirements for PPM were documented and potential clinical, electrophysiological, echocardiographic, and procedural predictors of PPM requirement were studied. Results: After TAVI, eight patients (29.6%) required PPM implantation due to high‐grade atrioventricular (AV) block. The prevalence of left bundle branch block increased from 13.8% to 57.7% directly after implantation (P = 0.001). Need for PPM was correlated to the depth of prosthesis implantation (r = 0.590; P = 0.001). At a cutoff point of 10.1 mm, the likelihood of pacemaker could be predicted with 87.5% sensitivity and 74% specificity and a receiver operator characteristic curve area of 0.86 ± 0.07 (P = 0.003). Of the seven patients with preexisting right bundle branch block (RBBB), four (57.1%) required PPM implantation after TAVI. Conclusions: High‐grade AV block requiring PPM implantation is a common complication following TAVI and could be predicted by a deeper implantation of the prosthesis. Patients with preexisting RBBB also seem to be at risk for the development of high‐grade AV block and subsequent pacemaker implantation. (PACE 2010; 1364–1372)  相似文献   
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铁皮石斛试管苗快速繁殖的研究   总被引:28,自引:0,他引:28  
兰科植物铁皮石斛(Dendrobium candidum Wall.ex Lind1.)的茎为常用名贵中药。多年来,主要依靠采收野生品种供药用和出口,致使野生资源枯竭,现已成为日益稀少的濒危植物。兰属种子和石斛属种子试管繁殖已积累不少资料,但是有关铁皮石斛种子试管繁殖的研究只有少量简单的报道,对其种子在试管繁殖过程中,所需外界条件的研究也不够  相似文献   
79.
外源性AA引起兔动脉条收缩,呈剂量依赖性;EPA抑制AA收缩血管亦呈浓度依赖性;DHA对AA收缩血管作用无明显影响。破坏血管内皮后AA收缩血管作用大为减弱,EPA抑制AA收缩血管作用也几乎消失。吲哚美辛能阻断AA收缩兔主动脉条的作用。兔主动脉6-keto-PGF、TXB2及其比值随AA浓度升高而增加,低剂量EPA对前列腺素类代谢无明显影响,较大剂量时则降低上述指标。  相似文献   
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Caloric restriction (CR) has been observed to retard aging processes and extend the maximum life span in rodents. In an effort to evaluate the effect of this nutritional intervention on physiologic variables in higher species, several nonhuman primate trials are ongoing. In particular, a study evaluating the independent effect of CR on the extent of atherosclerosis was initiated in 1993 in 32 adult cynomolgus monkeys. Therefore, the trial was designed to achieve identical cholesterol intake after animals were randomized to a control group or a calorie-restricted group (30% reduction from baseline caloric intake). The animals were routinely evaluated for glycated proteins, plasma insulin and glucose levels, insulin sensitivity, and specific measures for abdominal fat distribution by CT scans over a 4-year interval. The results from 4 years of intervention demonstrate that CR improves cardiovascular risk factors (such as visceral fat accumulation) and improves insulin sensitivity. In contrast to other primate studies with normolipidemic animals, CR had no independent effects on plasma lipid levels and composition in the presence of equivalent amounts of dietary cholesterol intake. Preliminary analysis of atherosclerotic lesion extent in the abdominal aorta has failed to demonstrate differences between control animals and CR animals. Follow- up studies are being conducted to determine the effect of CR on atherosclerosis extent in coronary and carotid arteries.   相似文献   
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