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Hepatocytes and bile duct epithelium express several types of cytokeratins, the characteristic intermediate-filament proteins of epithelial cells. The cytokeratin antigen expression was studied in normal and diseased livers, intrahepatic cholangiocarcinomas, and hepatocellular carcinomas by immunohistochemical methods using a panel of polyclonal and monoclonal antibodies to cytokeratins. Ten percent formaldehyde solution-fixed, paraffin-embedded sections obtained from ten patients without liver disease, 18 patients without liver disease, 18 patients with different stages of primary biliary cirrhosis, 14 patients with alcoholic hepatitis, ten patients with fatty liver hepatitis secondary to diabetes mellitus or morbid obesity, five patients with hepatocellular carcinomas, and five patients with cholangiocarcinomas were examined. The results suggested that hepatocytes and bile duct epithelium retain their distinct cytokeratin profiles in liver disease, including malignant transformation. Therefore, demonstration of cytokeratins in the liver is useful in establishing the cellular origin of neoplasms and understanding the pathogenesis of liver diseases.  相似文献   
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Distribution of Lewis(x) (Le(x)) and Lewis(y) (Le(y)) blood-group antigens was studied in nine formaldehyde-fixed, paraffin-embedded cholangiocarcinomas (CCs), 26 hepatocellular carcinomas (HCCs), and eight normal livers. All CCs, with one exception, expressed both Le(x) and Le(y) antigens on few or many cells. In HCCs Lex was expressed infrequently (8%), while Le(y) was detected in 31% of cases. Both markers, when present in HCCs, tended to be spotty. Fibrolamellar carcinomas and normal livers did not react with either Le(x) or Le(y) antigens; however, Le(y) antigen was observed occasionally in bile duct epithelial and ductular cells. In conclusion, inappropriate tissue distribution of Le(y) blood-group antigens was observed in CCs and, much less frequently, in HCCs. The high frequency of Le(x) antigen in CCs but not in HCCs may help in the differential diagnosis of these two tumors.  相似文献   
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Human leukocyte antigen (HLA) class I molecules are normally detected on most nucleated cells, but not on hepatocytes, while the expression of HLA class II antigens is mainly restricted to certain cell types of the immune system. This normal distribution pattern may be altered in human liver in a variety of disorders, particularly in infectious and immune diseases. In view of multiple infections and severe immune alterations in acquired immunodeficiency syndrome (AIDS), we studied the expression of HLA class I and class II antigens in liver obtained at autopsy from ten patients with AIDS and eight control patients, using a panel of monoclonal antibodies and the indirect immunofluorescence method. In spite of viral bacterial, and fungal infections, HLA class I antigens were detected on hepatocytes in only two patients with AIDS. Human leukocyte antigen class II antigens were found unexpectedly on bile duct epithelium in five of ten patients with AIDS and in one of eight control patients. The aberrant HLA class II antigen expression on bile ducts does not appear to be linked to bile duct damage or infection with cytomegalovirus or other agents, but may be related to immune alterations in patients with AIDS.  相似文献   
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S N Thung  M A Gerber 《Cancer》1981,47(7):1796-1799
Characteristic alterations of marker enzymes and tumor-associated antigens have been detected in the preneoplastic lesions of experimental hepatocarcinogenesis. An identical pattern of enzyme activity (increased gammaglutamyl transferase, loss of glucose-6-phosphatase, and canalicular adenosine triphosphatase) was demonstrated in a case of nodular "regenerative" hyperplasia of liver. The lack of marker antigens (alphafetoprotein, carcinoembryonic antigen, alpha 1-antitrypsin) in the hyperplastic nodules in this patient may be related to the discontinuation of oral contraceptive steroids four years earlier. The phenotypic changes of enzyme activity suggest that nodular "regenerative" hyperplasia of the liver in man is preneoplastic.  相似文献   
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Abstract: We report the first case of fatal anthrax meningoencephalitis in Hong Kong over the past 60 years. A 13 year-old boy presented with right lower quadrant pain, diarrhoea and progressive headache. Lumbar puncture yielded gram positive bacilli initially thought to be Bacillus cereus, a contaminant. He was treated with ampicillin and cefotaxime, but died 3 days after hospitalization. The organism isolated from blood and cerebrospinal fluid was later identified as Bacillus anthracis.  相似文献   
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报道了β-阻滞剂塞利洛尔的简便制备方法,即以对乙氧基苯胺为原料,经酰胺化,傅克反应,以环氧氯丙烷取代,最后用叔丁胺直接与环氧基反应开环等4步反应制得。比文献五步反应缩短了一步,产物经元素分析、红外光谱、核磁共振谱、质谱等分析确定结构。  相似文献   
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正常人口服磷酸川芎嗪的药代动力学研究   总被引:26,自引:0,他引:26  
蔡伟  董善年  楼雅卿 《药学学报》1989,24(12):881-886
本文建立了用高效液相色谱法测定人体内川芎嗪血药浓度的方法,以C18化学键合硅胶(10μgm)为固定相,以甲醇—水(58:42)为流动相,280 nm俭测,安眠酮为内标,进行定量测定,得出俭测限为3.5 ng(S/N=4),最低检测血清浓度为17.4 ng/ml,川芎嗪血药浓度在0.029~5.82μg/ml范围内,线性关系良好,方法回收率为99.84%。方法重现性好,专一性强,内源性物质、代谢产物及同时服用的药物均不干扰。用本法测定了健康人口服川芎嗪的药代动力学参数。  相似文献   
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