检测中国对虾非包涵体型杆状病毒的PCR方法的建立

中国对虾非体型杆状病毒（ＰｃＮＯＢＶ）是中国大陆养殖的中国对虾（Ｐｅｎａｅｕｓｃｈｉｎｅｎｓｉｓ）暴发性流行病－－白斑征的主要病原,与台湾流行的ＰｍＮＯＢⅢ、泰国的ＰｍＮＯＢⅡ及日本的ＲＶ－ＰＪ（＝ＰＲＤＶ）有相似的致病特征、形态学及组织病理学特征。为了角ＰｃＮＯＢＶ与ＰｍＮＯＢⅢ两种地域分布邻近的毒株基因水平的关系,并建立早期、敏感、特异的检测技术,利用氯化铯密度梯度超速离心技术分离纯化了ＰｃＮ     

Identification of a potential physiological substrate for oncogenic Ras-activated protein kinases in activated Xenopus egg extracts: Correlation with oncogenic RAS-induced cell cycle arrest

Activated Xenopus egg extracts are capable of undergoing cell-free cell cycling. Using these activated extracts, we previously showed that purified, bacterially expressed oncogenic human RasH protein arrests cell cycle progression. Because oncogenic Ras activates many serine/threonine protein kinases in Xenopus oocytes and egg extracts, it is possible that induction of cell cycle arrest involves the action of oncogenic Ras-activated kinases. Thus, the identification of the physiological substrates for oncogenic Ras-activated kinases is important for elucidating the molecular mechanism underlying oncogenic Ras-induced cell cycle arrest. We used ³²P-orthophosphate as a label to identify the potential substrates. Our results demonstrated that the ³²P-labeling of both a 32 and a 33 kDa protein were greatly enhanced by oncogenic Ras during the incubation of activated Xenopus egg extracts. The enhanced labeling correlated with the induced cell cycle arrest and was contributed by serine phosphorylation. Moreover, the 33 kDa protein was detected only in the presence of oncogenic Ras and was a serine-hyperphosphorylated form of the 32 kDa protein. Furthermore, new protein synthesis was not required for the enhanced labeling, consistent with the concept that the enhanced serine phosphorylation of the 32 kDa protein is by oncogenic Ras-activated protein kinases. In addition to serine phosphorylation, our results also suggested that an as yet unidentified modification of the 32 kDa protein might also be induced by oncogenic Ras. Our results suggest that the 32 kDa protein is a potential physiological substrate for oncogenic Ras-activated protein kinases. © 1996 Wiley-Liss, Inc.     

~3H-TdR诱发C_3H/10T1/2细胞恶性转化及其染色体分析

~3H-TdR进入体内后可直接参入分裂细胞的DNA中,造成对DNA的损伤。因此研究其致癌作用不但对其可能造成的污染具有实际意义,在理论上对探讨DNA损伤与细胞癌变的关系也有一定价值。一些作者把~3H-TdR直接注射到动物体内,观察肿瘤的发生率,未对~3H-TdR是否能升高诱发肿瘤发生率得出一致的结论。这可能是由于长期动物实验