复合型防老剂在低顺式聚丁二烯橡胶中的应用

以防老剂1010、防老剂1076、防老剂264、防老剂168和防老剂TNP为基础,研究了二元、三元和四元复合型防老剂对低顺式聚丁二烯橡胶的防老化作用,结果表明:复合型防老剂抗热、氧老化性能和抗热机械剪切性能均优于单一型防老剂,受阻酚类与亚磷酸酯类二元复合型防老剂综合性能最佳。

HIGN LEVEL EXPRESSION OF HEPATITIS C VIRUS CORE GENE IN E.COLI

Objective To express the hepatitis C virus (HCV) core gene in E . coli on a high level. Methods The cDNA coding for HCV core protein was amplified by polymerase chain reaction (PCR). The PCR product was purified and digested with restriction enzymes and inserted into the downstream of P RP L promoter of a high level expression vector pBV220 . HCV core gene was expressed in E . coli in a non fused form. The expression protein was analysed by SDS PAGE , and its immunoactivity was tested by ELISA . Results Sequence analysis of the amplified PCR products confirmed that we have successfully cloned and expresssed the intact core protein of HCV. SDS PAGE showed that a specific protein with a molecular weight of 21kDa at a level of 14.0% of the total bacterial proteins appeared in bacteria harboring pBV/HCVCore, while this protein was absent in the control bacteria harboring pBV220. The results of enzyme immunoassay analysis showed that this protein could be specifically recognized by the HCV positive sera from patients with hepatitis C .Conclusion The intact HCV core protein was successfully expressed in  E . coli  in a non fused form on a high level, and its immunoactivity was high.

Mepyramine对肝脏疾病肝微粒体膜流动性的影响

目的：探讨Mepyramine对肝脏疾病肝微粒体膜流动性的影响。方法：以1,6diphenyl1,3,5hexatriene(DPH)作为荧光探剂，应用荧光偏振技术研究大鼠急性肝炎、大鼠肝硬化肝微粒体膜流动性（LMMF）的变化，并在体外实验观察mepyramine(MPR)对LMMF的影响。结果：① LMMF在大鼠发生急性肝炎时升高，与对照组相比有显著性差异(P<0.01）,而大鼠发生肝硬化时降低，与对照组相比有显著性差异(P<0.05）。②10-4mol/L MPR可使正常大鼠、大鼠肝硬化及人体肝癌组织LMMF升高(P分别小于0.01，0.01，0.05)。结论：肝病时LMMF出现异常；MPR可以升高LMMF，其机制可能与阻断抗组胺药敏感性细胞色素P450(HP450)有关。