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BACKGROUND/AIMS: Gallbladder mucus itself has been recognized to play an important role in gallstone development. Despite the diverse mechanisms of stone induction and the differences in stone composition, there is a quantitative increase in the epithelial mucus production period before stone formation. As brown pigment stones are found frequently in gallstone disease, we conducted a study on gallbladders with brown pigment stones or combination stones with a brown periphery to evaluate the mucin content in the gallbladder epithelium in comparison to gallbladders with cholesterol stones and those without stones. METHODS: Gallbladder specimens were fixed in 10% formalin immediately after cholecystectomy and then embedded in paraffin. The specimens were sectioned for periodic acid-Schiff-alcian blue (PAS-AB, pH 2.5) double stain to evaluate the intra-epithelial mucin content. The PAS-AB index was calculated as a proportion of the PAS-AB-positive mucin area to the total epithelial area, using a computerized image analyzer. RESULTS: Evaluation of the PAS-AB index on the lining epithelia of gallbladders showed that it was 32.43 +/- 9.96% in gallbladders with brown stones, which is significantly (p < 0.001) higher than in gallbladders with cholesterol stones (15.63 +/- 6. 75%) and gallbladders without stones (9.55 +/- 4.77%). CONCLUSION: The results show that gallbladders with brown stones contain more abundant mucin than gallbladders with cholesterol stones or those without stones. They also suggest that the gallbladder epithelium per se might play a more important role in stone formation in those with brown stones than in those with cholesterol stones.  相似文献   
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This study represents an initial investigation into the adult psychological functioning of individuals born with craniofacial disfigurement. A total of 24 men and women born with a craniofacial anomaly completed paper and pencil measures of body image dissatisfaction, self-esteem, quality of life, and experiences of discrimination. An age- and gender-matched control group of 24 non-facially disfigured adults also completed the measures. As expected, craniofacially disfigured adults reported greater dissatisfaction with their facial appearance than did the control group. Craniofacially disfigured adults also reported significantly lower levels of self-esteem and quality of life. Dissatisfaction with facial appearance, self-esteem, and quality of life were related to self-ratings of physical attractiveness. More than one-third of craniofacially disfigured adults (38 percent) reported experiences of discrimination in employment or social settings. Among disfigured adults, psychological functioning was not related to number of surgeries, although the degree of residual facial deformity was related to increased dissatisfaction with facial appearance and greater experiences of discrimination. Results suggest that adults who were born with craniofacial disfigurement, as compared with non-facially disfigured adults, experience greater dissatisfaction with facial appearance and lower self-esteem and quality of life; however, these experiences do not seem to be universal.  相似文献   
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Syntaxin 1, synaptobrevins or vesicle-associated membrane proteins, and the synaptosome-associated protein of 25 kDa (SNAP-25) are key molecules involved in the docking and fusion of synaptic vesicles with the presynaptic membrane. We report here the molecular, cell biological, and biochemical characterization of a 32-kDa protein homologous to both SNAP-25 (20% amino acid sequence identity) and the recently identified SNAP-23 (19% amino acid sequence identity). Northern blot analysis shows that the mRNA for this protein is widely expressed. Polyclonal antibodies against this protein detect a 32-kDa protein present in both cytosol and membrane fractions. The membrane-bound form of this protein is revealed to be primarily localized to the Golgi apparatus by indirect immunofluorescence microscopy, a finding that is further established by electron microscopy immunogold labeling showing that this protein is present in tubular-vesicular structures of the Golgi apparatus. Biochemical characterizations establish that this protein behaves like a SNAP receptor and is thus named Golgi SNARE of 32 kDa (GS32). GS32 in the Golgi extract is preferentially retained by the immobilized GST-syntaxin 6 fusion protein. The coimmunoprecipitation of syntaxin 6 but not syntaxin 5 or GS28 from the Golgi extract by antibodies against GS32 further sustains the preferential interaction of GS32 with Golgi syntaxin 6.  相似文献   
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