| 1 | Correlation of glycosyltransferases mRNA expression in extrahepatic bile duct carcinoma with clinical pathological characteristics显示文摘BACKGROUND: The incidence of extrahepatic bile duct carcinoma (EBDC) has been increasing, especially in aged people, but the glycobiology of the tumor is not elucida- ted. In this study we investigated the expressions of three glycosyltransferases in 35 patients with EBDC and 35 pa- tients with benign biliary duct disease (BBDD) as well as their clinicopathological significance. METHOD: The patients were divided into several sub- groups by tumor differentiation, TNM stage, and invasion by the standards recommended by UICC. Tumor samples were immediately frozen in liquid nitrogen after resection, followed by mRNA determination of enzymes in the tissue using a mRNA selective reverse trancriptase-polymerase chain reaction kit. The mRNA levels of different groups were semi-quantitatively compared. RESULTS: The mRNA levels of N-acetylglucosaminyltrans- ferase V (GnT-V) and a subtype of α2,3 sialyltransferases for N-glycans, ST3Gal- were elevated 7.75 and 5.39 times in EBDC as compared with BBDD, respectively, and they were correlated to several clinicopathological factors including tumor advancement, differentiation, metastasis, and invasiveness. The mRNA expression of another sialyl- transferase, ST6Gal- , was also 0.63-fold higher in EBDC than in BBDD, but not involved in the clinicopathological characteristics. CONCLUSION: The elevated expression of these three gly- cosyltransferases can be considered as an important molecu- lar event in the occurrence and progression of EBDC. | Xiao-Ling Jin, Shu-Sen Zheng, Bing-Sheng Wang and Hui-Li Chen Nanjing, China Department of General Surgery, Nanjing First Hospi- tal Affiliated to Nanjing Medical University, Nanjing 210006, China Department of Hepatobiliary Surgery, First Affiliated Hospital, Zhe- jiang University School of Medicine, Hangzhou 310003, China Department of General Surgery, Zhongshan Hospital, Fudan Universi- ty, Shanghai 200032 , China and Key Laboratory of Glycocon- jugate Research, Ministry of Health, Department of Biochemistry, Fudan University School of Medicine, Shanghai 200032, China | 2004 | Hepatobiliary & Pancreatic Diseases International2004，3，2： | 6 |
| 11 | Implementing Semantic Deduction of Propositional Knowledge in an Extension Multi-layer Perceptron显示文摘The paper presents an extension multi-laye r p erceptron model that is capable of representing and reasoning propositional know ledge base. An extended version of propositional calculus is developed, and its some properties is discussed. Formulas of the extended calculus can be expressed in the extension multi-layer perceptron. Naturally, semantic deduction of prop ositional knowledge base can be implement by the extension multi-layer perceptr on, and by learning, an unknown formula set can be found. | HUANG Tian-min,PEI Zheng (Department of Applied Mathematics, Southwest Jiaotong Universi ty,Chengdu 610031,China) | 2003 | Chinese Quarterly Journal of Mathematics2003，18，3： | 0 |
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