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121.
Bile glycoprotein mucin in sludge occluding biliary stent 总被引:2,自引:0,他引:2
Endoscopic biliary stenting is a common treatment for the palliation of obstructive jaundice caused by inoperable malignant hepatobiliary tumors and benign strictures. The biliary stent, however, often becomes nonfunctional as a result of occlusion. In this study, we sought to confirm that bile glycoprotein mucin was a factor in stent occlusion and to investigate its possible role in biliary-stent blockage. The high-molecular-weight glycoprotein fraction was isolated from stent sludge with the use of gel filtration and a cesium chloride density gradient. This fraction was analyzed for amino-acid and carbohydrate compositions and was identified by means of immunoblotting with a specific monoclonal antibody against human gallbladder mucin. Furthermore, the distribution of bile glycoprotein mucin in stent sludge was immunologically demonstrated with fluorescent antibody, and the relationship between bile glycoprotein mucin and bacteria (demonstrated with DAPI stain) was observed. The high-molecular-weight glycoprotein extracts isolated from 11 patients' stent sludge showed strongly positive immunoreactivity with the monoclonal antibody against human gallbladder mucin. Immunofluorescence studies showed that very bright fluorescent signals of bile glycoprotein mucin often appeared on the surface of pigmented deposits, at the periphery of clumps of bacteria and along the inner wall of stents. In nonpigmented sludge, we noted fluorescent signals of bile glycoprotein mucin dispersed among clumps of bacteria. Bile glycoprotein mucin is a constituent of stent sludge. It may play a role in stent occlusion by affecting bacterial adherence to the stent surface or by promoting stent-sludge accumulation as one kind of cement among substances such as calcium bilirubinate and clumps of bacteria. 相似文献
122.
We described a rare case of carcinoma expleomorphic adenoma in which mucoepidermoid carcinoma arise from a previous incompletely excised pleomorphic adenoma of the submandibular gland. The tumor was surgically resected along with a modified radical neck dissection and postoperative radiotherapy. The patient remained disease free 3 years after the last operation. The pathology showed concurrent presence of Warthin's tumor in the specimen. The concurrent presence of mucoepidermoid carcinoma, pleomorphic adenoma, and synchronous Warthin's tumor make this case unique, and such a combination associated with the submandibular gland has not been documented in the literature before. 相似文献
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Corton MM Wai CY Vakili B Boreham MK Schaffer JI Coleman RL 《American journal of obstetrics and gynecology》2003,189(3):647-651
OBJECTIVE: This study was undertaken to evaluate the impact of a pelvic dissection course on resident proficiency in surgical anatomy. STUDY DESIGN: Over a 1-year period, residents attended a course consisting of pretesting and posttesting, lectures, and pelvic dissection. Tests results were analyzed using paired Student t test, analysis of variance, and Kruskal-Wallis statistics. RESULTS: Of 42 residents, 24 completed all testing (study cohort). On written and practical examinations, resident scores improved a median of 42% and 29% (both P<.0001). Postgraduate year (PGY) 2 demonstrated the greatest improvement on the practical and PGY-3s demonstrated the greatest improvement on the written. Baseline written and practical results discriminated PGY level (construct validity): PGY-2=PGY-3相似文献
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Tang WK Chan SS Chiu HF Wong KS Kwok TC Mok V Ungvari GS 《International journal of geriatric psychiatry》2003,18(8):706-710
BACKGROUND: Little is known about the performance of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) in the screening of post-stroke dementia (PSDE). METHODS: At 3 months after the index stroke, a research assistant administered the IQCODE to relatives of 189 Chinese patients with acute stroke who were consecutively admitted to a general hospital. A psychiatrist, who was blind to the IQCODE scores, interviewed all 189 patients and made DSM-IV diagnosis of dementia, which served as the benchmark for judging the performance of IQCODE in screening PSDE. RESULTS: The optimal cut-off point of IQCODE was 3.40. The sensitivity, specificity, and positive and negative predictive values of IQCODE, and the area under the receiver operating characteristic curve, were 88%, 75%, 33%, 98%, and 0.88, respectively. CONCLUSIONS: When used as a sole instrument, IQCODE does not appear to be useful in screening PSDE in Chinese elderly. 相似文献
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128.
Nasopharyngeal carcinoma (NPC) is closely related with Epstein-Barr virus (EBV). Almost every NPC tumor cells carries clonal EBV genomes. Detection of EBV derived latent membrane protein-1 gene (LMP-1) indicate the presence of NPC. Middle ear effusion (MEE) is a frequent sign of NPC. There have been no reports on LMP-1 in MEE. Tympanocentesis of 88 ears with MEE of 66 patients were done in three groups of patients, group (I) NPC, 31 patients, 50 ears, (II) other head and neck cancers, five patients, six ears and (III) no cancer history, 30 patients, 32 ears. The middle ear aspirate and nasopharyngeal swab specimen were collected to detect LMP-1 with a PCR-based method. Sixty aspirates (68%) out of 88 ears with MEE had enough DNA for PCR amplification. LMP-1 was detected in six middle ear aspirate specimen from three patients in group I who had petrous apex invasion. LMP-1 was detected in 30 swab specimen (93.8%) out of 32 nasopharyngeal swabs in group I. LMP-1 was not detected in middle ear aspirates or nasopharyngeal swab in group II and III patients. LMP-1 was not detected in MEE in patients without NPC. In NPC patients, the detection of LMP-1 may indicate petrous apex invasion. 相似文献
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130.
OBJECTIVE: Cell adhesion is an important cell survival determinant and disruption of integrin-mediated signal transduction may be involved in anchorage-dependent cell death. We have examined the processing of focal adhesion kinase (FAK), a component of integrin-mediated signal transduction, in a cisplatin-sensitive human ovarian epithelial cancer cell line (OV2008), to test the possible role of FAK degradation in the control of apoptosis via regulation of cell attachment. METHODS: FAK processing after cisplatin treatment in the absence or presence of various caspase-inhibiting substances was analyzed by Western blot. Caspase-inhibiting activities were introduced using cell-permeable peptides or adenoviral vector. RESULTS: Cisplatin-induced caspase 3 and FAK cleavage, cell detachment from the growth surface, and apoptosis in a temporally related and concentration-dependent manner. FAK fragments were detected exclusively in cells detached from the culture surface. Addition of active caspase 3 to the whole cell lysate elicited a similar pattern of FAK cleavage. Pretreatment of whole cell lysates and cells with tetrapeptide inhibitors of caspases significantly decreased FAK cleavage induced by exogenous active caspase 3 and cisplatin, respectively. Overexpression of X-linked inhibitor of apoptosis protein (Xiap), an endogenous caspase inhibitor, attenuated the cisplatin-induced FAK processing, morphologic changes, and apoptosis. The inhibitory action of Xiap was abolished with the deletion of a functional motif required for caspase inhibition. CONCLUSION: These findings are consistent with our hypothesis that FAK processing is in part mediated by caspase 3, the activation of which is modulated by Xiap. 相似文献