【摘要】 <正> 在人肝癌高发区江苏启东县,自然鸭群中的肝癌发生率很高。人与鸭肝癌发生率的正相关性提示了可能存在共同的环境因素——嗜肝病毒及化学致癌物。这两者可能是肝癌的致癌因素。但鸭乙肝病毒(DHBV)的检出率,在人肝癌高发区(如启东)和低发区(上海青浦县)并无明显差异,均在40％～50％左右。本实验室,在研究鸭肝癌中DHBV的作用时,意外地发现:在2例启东鸭肝癌及其癌旁组织,1例癌前肝组织及1例非癌性鸭肝组织中,除DHBV更多还原

【Abstract】 It is the first report to describe the presence of a HBV-like DNA sequence in 2hepatoma and their tumor surrounding liver tissues, 1 precancerous and 1 non-malignantliver tissue of ducks collected from Qi-Dong County of China. The HBV-like sequenceswere either in an episomal form of 3.2kb or in an integrated form of various sizes, whilethe DHBV DNA sequences (3.0 kb) were either present or absent in these tissues and indifferent size pattern. Furthermore,there was no evidence of cross-hybridization betweenHBV-like sequences in duck and DHBV DNA. A 3.2 kb HBV-like DNA sequence hasbeen cloned from one duck hepatoma (40k) and been further analysed for its genomicmap. The mapping data indicated that it had one unique EcoRI site, 3 BgⅢ sites, 1BamHⅠ site and multiple sites for AvaⅠ, HpaⅠ and HpaⅡ. The pattern was different fromthose HBV clones reported previously. The HBV-like sequences have not been detectedfrom duck livers collected from Qing-Pu County of Shanghai. The potential significanceof the HBV-like sequences was discussed.更多还原