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J Oral Pathol Med (2012) 41 : 47–53 Objective: The aim of this study was to investigate the presence of CD1a‐positive Langerhans cells and their relationship with E‐cadherin in minor salivary gland tumors. Methods: Twenty‐seven minor salivary gland tumors were investigated using immunohistochemistry for CD1a and E‐cadherin. Results: A significant difference regarding the mean density of CD1a‐positive Langerhans cells was observed between pleomorphic adenomas and malignant tumors studied (P = 0.001). No CD1a‐positive cells were detected in most cases (n = 5) of cystic adenoid carcinomas. CD1a‐positive cells were detected in one mucoepidermoid carcinoma case, and six low‐grade polymorphous adenocarcinomas cases. Comparison of the mean density of CD1a‐positive cells between the three malignant tumors showed no significant difference (P = 0.127). No significant difference was observed in the presence of E‐cadherin between tumors (P = 0.73), but it was detected in 24 cases. Conclusions: The lack of CD1a‐positive in malignant salivary gland tumors facilitates the neoplastic development and suggests that these cells might be useful as auxiliary diagnostic and prognostic tool in minor salivary gland tumors. Furthermore, it is suggested that E‐cadherin mediates cell adhesion in these tumors although we did not demonstrate significance.  相似文献   
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After inserting a catheter into a vessel, guidewire exchange technique must be used to maintain vascular access. If the lumen of the catheter is blocked and the guidewire exchange cannot be used, the catheter can only be removed, vascular access is lost, and an alternate vascular approach attempted. We describe a technique to remove the blocked catheter and still maintain vascular access. © 2008 Wiley‐Liss, Inc.  相似文献   
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Purpose

Gallbladder diseases and cholecystectomy may play a role in the development of colorectal cancer (CRC). Our aim was to investigate the association between cholecystectomy and CRC risk overall and by sex, family history, anatomical location, and tumor mismatch repair (MMR) status.

Methods

This study comprised 5847 incident CRC cases recruited from population cancer registries in Australia, Canada, and the USA into the Colon Cancer Family Registry between 1997 and 2012 and 4970 controls with no personal history of CRC who were either randomly selected from the general population or were spouses of the cases. The association between cholecystectomy and CRC was estimated using logistic regression, after adjusting for confounding factors.

Results

Overall, there was no evidence for an association between cholecystectomy and CRC (odds ratio [OR] = 0.88, 95 % confidence interval 0.73, 1.08). In the stratified analyses, there was no evidence for a difference in the association between women and men (P = 0.54), between individuals with and without family history of CRC in first-degree relative (P = 0.64), between tumor anatomical locations (P = 0.45), or between MMR-proficient and MMR-deficient cases (P = 0.54).

Conclusion

Cholecystectomy is not a substantial risk factor for CRC, regardless of sex, family history, anatomical location, or tumor MMR status.
  相似文献   
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The degree of admixture in Brazil between historically isolated populations is complex and geographically variable. Studies differ as to what the genetic and phenotypic consequences of this mixing have been. In Northeastern Brazil, we enrolled 522 residents of Salvador and 620 of Fortaleza whose distributions of self-declared color were comparable to those in the national census. Using the program Structure and principal components analysis there was a clear correlation between biogeographic ancestry and categories of skin color. This correlation with African ancestry was stronger in Salvador (r=0.585; P<0.001) than in Fortaleza (r=0.236; P<0.001). In Fortaleza, although self-declared blacks had a greater proportion of European ancestry, they had more African ancestry than the other categories. When the populations were analyzed without pseudoancestors, as in some studies, the relationship of ‘race'' to genetic ancestry tended to diffuse or disappear. The inclusion of different African populations also influenced ancestry estimates. The percentage of unlinked ancestry informative markers in linkage disequilibrium, a measure of population structure, was 3–5 times higher in both Brazilian populations than expected by chance. We propose that certain methods, ascertainment bias and population history of the specific populations surveyed can result in failure to demonstrate a correlation between skin color and genetic ancestry. Population structure in Brazil has important implications for genetic studies, but genetic ancestry is irrelevant for how individuals are treated in society, their health, their income or their inclusion. These track more closely with perceived skin color than genetic ancestry.  相似文献   
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Background

The Activity Measure for Post-Acute Care was developed to evaluate the limitations of activities of adult individuals with different health conditions.

Objectives

To translate and cultural adapt the Activity Measure for Post-Acute Care short forms for outpatients into Portuguese–Brazilian, to verify the comprehension of the items and categories of the responses by users of the rehabilitation services and to analyze the reliability indices of the instrument.

Methods

Translation and back-translation were conducted by two independent teams. Cognitive interviews (n = 2) evaluated the comprehension of the translated version among patients. Item reliability and consistency was also investigated.

Results

There was conceptual equivalence between the translated and original versions. For some items, the information was modified in order to attend to the measurement units used in Brazil. Comparative analyses of the translated versions chose the most appropriate term to capture the English content. The few discrepancies identified in the back-translation were solved by consensus. The cognitive interviews detected few comprehension problems, which were solved by means of repetition of the item statement and use of examples to clarify the specificity of the information. The final translated short forms of the instrument showed excellent test-retest reliability and inter-examiner reliability indices, as well as high internal consistency.

Conclusion

The Portuguese version of the Activity Measure for Post-Acute Care short forms will provide Brazilian clinicians and researchers with an up-to-date instrument for the evaluation of functioning of adults with various clinical conditions who attend outpatient rehabilitation settings.  相似文献   
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