To compare the mass fraction of total flavonnoids and tannin of three kinds of Herba Euphorbia humifusa and their antibacaterial activity in vitro,the total flavonoids and tannin of Euphorbia humifusa Willd,E.maculata L.and E.heyneana Spreng from Shaanxi province were determined by UV-Vis spectrophotometry,and their minimal inhibitory concentration(MIC) and minimal bactericidal concentrations(MBC) against Escherichia coli,Salmonella typhimurium,Staphylococcus aureus and Streptococcus agalactiae in vitro were determined by broth microdilution method.The result showed that the mass fraction of total flavonoids of E.humifusa,E.maculata and E.heyneana was 16.53,18.62,22.65 mg/g,respectively,and the mass fraction of tannin was 38.31,32.78,41.44 mg/g,respectively.Against Escherichia coli,their MIC,MBC all were 125 g/L.Against Salmonella typhimurium,MIC was 62.5,31.25,62.5 g/L,and MBC was 125,62.5,250 g/L,respectively.Against Staphylococcus aureus,MIC was 125,31.25,62.5 g/L,and MBC was 250,125,62.5 g/L,respectively.Against Streptococcus agalactiae,MIC was 125,62.5,125 g/L,and MBC was 125,250,125 g/L,respectively.The plant of E.maculate,especially,E.heyneana from Shaanxi province is a new potential origin.

The homologous RNases RNase E and RNase G are widely distributed in bacteria and function in many important physiological processes, including mRNA degradation, rRNA maturation and so on. In this study, the crystallization and preliminary X-ray analysis of RNase G from Escherichia coli is described. Purified recombinant E. coli RNase G, which has 497 amino acids, was crystallized in the cubic space group F432, with unit-cell parameters a = b = c = 219.84 A. X-ray diffraction data were collected to a resolution of 3.4 A.

In this study using the transgenic(GFP) fibroblasts of Saanen dairy goat as donor cells and using the abattoir-derived oocytes of normal goat as recipient cells the nuclear transfer experiments had been processed.During experiments the optimization of electricfusion experiment(parameters) of transgenic nuclear transfer embryos had been done.For the treatment of transgenic reconstruction embryos of Saanen dairy goat,the electricfusion parameter of group B in(experiment) plans(1.5kV/cm for 30 μs and pulse interval for 1s) is most suitable for the(transgenic) reconstruction embryos of Saanen dairy goat,the electricfusion rate of 89.4% for cell-cytoplast complexes and the cleavage rate of 68.0% for reconstructed embryos have been obtained.

以新疆野生盘羊（Ovis ammon）和萨能奶山羊转基因（GFP）成纤维细胞为核供体细胞,分别以绵羊卵母细胞和普通山羊卵母细胞为受体细胞进行了核移植,对不同种类核移植重构卵进行电融合处理,发现盘羊重构卵电融合参数为1.4 kV/cm、20μs/次、间隔1 s时的重构卵融合率最高;对于转基因（GFP）萨能奶山羊重构卵的处理,电融合前先放入融合液中于38.5℃下平衡5 min,融合时电融合参数为1.5 kV/cm、20μs/次、间隔1 s时的融合率最高。实验中发现将融合后的两种重构胚胎先置入IVM培养液中于38.5℃下平衡4 h,可降低重构胚胎的死亡率,提高发育质量和卵裂率。