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Epithelial to mesenchymal transition (EMT) is a biological process in which the epithelial cells, transform to mesenchymal cells via multiple biochemical modifications. Immunohistochemical method was used to examine the expression of EMT-related proteins: Slug, E-cadherin and fibronectin, in 41 cases of sinonasal inverted papilloma (SIP), 33 cases of sinonasal squamous cell carcinoma (SNC), and 22 cases of normal mucosa as a control. In all cases negative viral status was previously confirmed using both in situ hybridization and immunohistochemical method. The immunoexpression of Slug and fibronectin were significantly increased in the SNC group as compared to SIPs and control cases. The immunoexpresssion of Slug was also higher in SIPs as compared to controls. The immunoexpression of E-cadherin was significantly lower in SNCs group as compared with SIPs and controls, but no statistically significant difference in E-cadherin immunoexpression was noted between SIPs and control cases. There were statistically significant negative correlations between immunoexpression of Slug vs E-cadherin, E-cadherin vs fibronectin and positive correlation between Slug vs fibronectin in SNC. Statistically significant correlation between Slug and fibronectin immunoexpression in SIPs was also found. In conclusion, our findings suggest that relationships between Slug, E-cadherin and fibronectin could potentially point to EMT in the sinonasal cancer. Lack of correlation between EMT-related proteins in tested SIPs could reflect a benign nature of those cases.  相似文献   
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To evaluate perceived pain during repetitive annual endometrial sampling at gynaecologic surveillance in asymptomatic women with Lynch syndrome (LS) over time and in addition to symptomatic women without LS, undergoing single endometrial sampling. In this prospective study, 52 women with LS or first degree relatives who underwent repetitive annual gynaecological surveillance including endometrial sampling of which 33 were evaluated twice or more and 50 symptomatic women without LS who had single endometrial sampling, were included. Pain intensity was registered with VAS scores. Differences in pain intensities between subsequent visits (in LS) and between the two groups were evaluated. The use of painkillers before endometrial sampling was registered. If women with LS decided for preventive surgery, the reason was recorded. The LS group reported a median VAS score of 5.0 (range 0–10) at the first surveillance (n = 52) and at the second visit (n = 24). Women who repeatedly underwent endometrial sampling more often used painkillers for this procedure. During the study period 7/52 (13 %) women with LS choose for preventive surgery, another 4/52 (8 %) refused further endometrial sampling. Painful endometrial sampling was mentioned as main reason to quit screening. The median VAS score of the 50 symptomatic women was 5.0 (range 1–9). Endometrial sampling, irrespective of indication, is a painful procedure, with a median VAS score of 5.0. During subsequent procedures in women with LS, the median pain score does not aggravate although one in five women chose an alternative for endometrial sampling.  相似文献   
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Alanine substitutions and selected deletions have been used to localize amino acids in QnrB essential for its protective activity. Essential amino acids are found at positions i and i−2 in the pentapeptide repeat module and in the larger of two loops, where deletion of only a single amino acid compromises activity. Deletion of 10 amino acids at the N terminus is tolerated, but removal of 3 amino acids in the C-terminal dimerization unit destroys activity.  相似文献   
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