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21.
Clinical Rheumatology - The aim of this study was to evaluate the relationships among the disease activity, illness perception, daily life performance, anxiety and depression status as potential...  相似文献   
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Complications of valve replacement are diverse. In addition to morbidity due to the prosthetic valve itself (e.g. endocarditis, thrombosis), complications due to operative technique may occur in complex cases, as in aortic valve replacement with annular enlargement. Postoperative echocardiography is a simple, non-invasive method to evaluate patients with prosthetic valves. Detailed knowledge of the surgical technique employed and of probable complications is necessary to make an accurate diagnosis. The case is reported of a woman with aortic valve replacement and annular enlargement who had mitral regurgitation due to a tear in the anterior mitral leaflet as a complication of Manouguian's annulus enlargement.  相似文献   
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Behçet's disease is an inflammatory disorder of unknown etiology. Genetic tendency has an important role in its pathogenesis, and HLA‐B51, a class I MHC antigen, has been recognized as the strongest susceptibility factor for Behçet's disease. Despite the confirmation of the association of HLA‐B51 with Behçet's disease in different populations, its pathogenic mechanisms remain elusive. HLA‐B51 differs in only two amino acids from HLA‐B52, other split antigen of HLA‐B5, which is not associated with Behçet's disease. These two amino acids are located in the B pocket of the antigen‐binding groove, which occupies the second amino acids of the bound peptides. To understand the nature of the HLA–peptide interactions, differences in structure and dynamics of two HLA alleles were investigated by molecular dynamics simulations using YAYDGKDYI, LPRSTVINI, and IPYQDLPHL peptides. For HLA‐B51, all bound peptides fluctuated to larger extent than HLA‐B52. Free energy profiles of unbinding process for YAYDGKDYI by steered molecular dynamics simulations showed that unbinding from HLA‐B52 results in greater free energy differences than HLA‐B51. These results suggest the possibility of an instability of HLA‐B51 associated with the repertoire of peptides, and this finding may provide significant insight to its pathogenic role in Behçet's disease.  相似文献   
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BackgroundThe aim of this study is to compare speech outcomes, fistula rates, and rates of secondary speech surgeries after palatoplasty using Furlow palatoplasty or type 2b intravelar veloplasty for soft palate repair.Patients and methodsPatients with unilateral cleft lip and palate who had either Furlow palatoplasty or intravelar veloplasty for soft palate repair were retrospectively evaluated for demographic and perioperative variables and speech outcomes. Fistula rate, secondary surgical intervention for improved speech results, and findings of speech assessment were further reviewed for the patients who met the inclusion criteria.ResultsA total of 76 patients, 36 in the Furlow palatoplasty group and 40 in the intravelar veloplasty group, were included in the study. In the speech assessment, nasalance values were statistically similar between the two groups. Also, there was no statistically significant difference between the groups in velopharyngeal motility (p = 0.103). The total rates of secondary surgeries and fistula were statistically similar between the groups (p = 0.347 and 0.105, respectively).ConclusionThe similar outcomes of speech and surgical evaluation between the two groups make the surgeon's preference determinant in the selection of the surgical technique for soft palate repair.  相似文献   
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Increased deposition of the extracellular matrix components, particularly collagen, is a central phenomenon in liver fibrosis. Stellate cells, the central mediators in the pathogenesis of fibrosis are activated by free radicals, and synthesize collagen. Melatonin is a potent physiological scavenger of hydroxyl radicals. Melatonin has also been shown to be involved in the inhibitory regulation of collagen content in tissues. At present, no effective treatment of liver fibrosis is available for clinical use. We aimed to test the effects of melatonin on dimethylnitrosamine (DMN)-induced liver damage in rats. Wistar albino rats were injected with DMN intraperitoneally. Following a single dose of 40 mg/kg DMN, either saline (DMN) or 100 mg/kg daily melatonin was administered for 14 days. In other rats, physiologic saline or melatonin were injected for 14 days, following a single injection of saline as control. Hepatic fibrotic changes were evaluated biochemically by measuring tissue hydroxyproline levels and histopathogical examination. Malondialdehyde (MDA), an end product of lipid peroxidation, and glutathione (GSH) and superoxide dismutase (SOD) levels were evaluated in blood and tissue homogenates. DMN caused hepatic fibrotic changes, whereas melatonin suppressed these changes in five of 14 rats (P < 0.05). DMN administration resulted in increased hydroxyproline and MDA levels, and decreased GSH and SOD levels, whereas melatonin reversed these effects. When melatonin was administered alone, no significant changes in biochemical parameters were noted. In conclusion, the present study suggests that melatonin functions as a potent fibrosuppressant and antioxidant, and may be a therapeutic choice.  相似文献   
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ObjectiveThe aim was to compare coronary high-definition CT (HDCT) with standard-definition CT (SDCT) angiography as to radiation dose, image quality and accuracy.ResultsThe intraclass correlation coefficient (ICC) of measured vessel attenuation values in SDCT between the two radiologists was exceedingly good. The ICC was higher in HDCT. The radiation dose of HDCT was higher than that of SDCT. The mean tube current was 180 (mA) in HDCT and 147(mA) in SDCT with the same tube voltage (kVp). There was no significant difference between image quality.ConclusionHDCT has a higher radiation dose but has much more atenuation and the spatial resolution which improve measurement accuracy for imaging coronary arteries.  相似文献   
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Background

Longlasting and unbearable pain is the most common and striking symptom of chronic pancreatitis. Accordingly, pain relief and improvement in patients'' quality of life are the primary goals in the treatment of this disease. This systematic review aims to summarize the available data on treatment options.

Methods

A systematic search of MEDLINE/PubMed and the Cochrane Library was performed according to the PRISMA statement for reporting systematic reviews and meta-analysis. The search was limited to randomized controlled trials and meta-analyses. Reference lists were then hand-searched for additional relevant titles. The results obtained were examined individually by two independent investigators for further selection and data extraction.

Results

A total of 416 abstracts were reviewed, of which 367 were excluded because they were obviously irrelevant or represented overlapping studies. Consequently, 49 full-text articles were systematically reviewed.

Conclusions

First-line medical options include the provision of pain medication, adjunctive agents and pancreatic enzymes, and abstinence from alcohol and tobacco. If medical treatment fails, endoscopic treatment offers pain relief in the majority of patients in the short term. However, current data suggest that surgical treatment seems to be superior to endoscopic intervention because it is significantly more effective and, especially, lasts longer.  相似文献   
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