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991.
Adenocarcinomas of the urinary bladder are rare (1-5% of bladder tumours) and of notoriously poor prognosis. About one third of such tumours arise in urachal remnants related to the bladder. This is believed to be the first report of in situ change in the urachal remnant. The patient presented with mucusuria and computed tomography showed a typical urachal cyst. After excision the cyst was found to contain mucinous adenomatous epithelium but without invasion of the basal lamina. Pathological stage is the best prognostic indicator in urachal tumours. Prompt investigation and management of mucusuria may allow the diagnosis of urachal tumours in this preinvasive stage.  相似文献   
992.
A 39-year-old man, with no history of alcohol intake, who had had an esophago-ileo-colo-gastroplasty with ileotransversostomy, developed diplopia, seizures, metabolic acidosis, and cardiac failure and finally refractory hyperdynamic shock. He died 20 h after admission to our intensive care unit from cardiocirculatory collapse. Postmortem results revealed low erythrocyte transketolase activity, which was increased by 22% by in vitro addition of thiamine diphosphate (TDP effect). Cerebral pathology showed the alterations of Wernicke's encephalopathy. We discuss the possible mechanisms of fatal cardiovascular collapse and the unusual presentation of a case without a history of alcoholic intake or clinical malnutrition.  相似文献   
993.
BACKGROUND: Pancreatic adenosquamous carcinoma (ASqC) is an unusual histologic subtype of nonendocrine neoplasia of the pancreas. Although fine needle aspiration cytology (FNAC) is now accepted as a reliable procedure for the diagnosis of pancreatic malignancies, many of these unusual tumors are still diagnosed after surgery or at necropsy. CASES: Between January 1995 and July 1996, 3 of 35 primary pancreatic malignant tumors were diagnosed as ASqC based on computed tomography-guided FNAC. After cytologic diagnosis, all three patients were treated with neoadjuvant chemotherapy and radiotherapy. Two patients completed the treatment and underwent a surgical pancreatic-duodenectomy with antrectomy. The remaining patient is currently under treatment. That patient had a highly infiltrative pancreatic mass that affected the muscular small bowel wall. An endoscopic biopsy was performed. The cytologic diagnosis was confirmed by histology in all cases. Immunohistochemically both components, squamous and glandular, showed reactivity for several keratins, while only the glandular pattern was reactive with carcinoembryonic antigen (CEA). CONCLUSION: FNAC is an accurate, rapid and sensitive tool in the diagnosis of ASqC of the pancreas. We recommend a careful search for both malignant components. Immunoreactivity for CEA can be of help in the detection of the glandular component of this tumor.  相似文献   
994.
Gingipain R2 is a 50 kDa proteinase from the oral pathogenic bacterium Porphyromonas gingivalis. This proteinase, which displays no significant sequence homology to any protein previously analyzed by X-ray crystallography, has been crystallized using the vapor diffusion method. Two different crystal forms were obtained from a solution containing polyethylene glycol (MW 8,000) (space group P2(1)2(1)2(1)) or magnesium sulfate (space group R3) as precipitating agent. Complete diffraction data sets have been collected up to 2.0 and 2.9 A resolution, respectively. Cell dimensions are a = 51.9 A, b = 79.9 A, and c = 99.6 A (P2(1)2(1)2(1)), and a = b = 176.6 A, and c = 143.4 A (R3). Considerations of the possible values of Vm accounts for the presence of one monomer per asymmetric unit in the case of the orthorhombic crystal form, whereas the rhombohedral crystal form, together with the analysis of the self-rotation function, could accommodate a tetramer in the asymmetric unit.  相似文献   
995.
Although ultrasound is used extensively in medical therapies and diagnostics, it has been recognized only recently as a method for external controlled diversity of drugs. In this paper, firstly, a literature review on drug delivery and the combination with ultrasound is given. Then an experiment is described on measuring the release of a model drug (hexabrix) under ultrasound irradiation, from a polymer carrier.  相似文献   
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The synthesis of a series of azabicyclic indole esters is described and their potency reported as 5-HT4 receptor antagonists. Optimization of the most potent compound (19) by preparing the corresponding oxazino[3,2-a]indole ester afforded 34, which had a pIC50 of 9.5 in the guinea pig distal colon longitudinal muscle myenteric plexus preparation.  相似文献   
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