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111.
对1587名献血员进行了抗-HCV检测,总阳性率5.60%,在不同职业中农民较高,占6.72%,30岁以上为12.76%。我站自改进采浆工艺,严格使用一次性消毒器具后,未发现HCV交叉感染。职业献血者抗-HCV阳性率高达35.48%,易造成输血后HCV感染。对HCV感染OD值阳性30人又进行4-6个月的观察复测,其中16人OD值下降,6人上升,认为OD值的变化与自限性HCV感染有关。 相似文献
112.
Abstract The present paper deals with a new species Habrophlebiodes zijinensis sp. nov. collected in Nanjing, Jiangsu Povince, China. 相似文献
113.
Summary The direct, lipase-catalyzed esterifications of glycerol-3-phosphate in an organic solvent system and in a solvent free system were carried out. In a solvent free system only, LPA synthesis could be achieved within the acceptable reaction time. Open reaction system was preferable to closed reaction system for LPA synthesis. Yield of LPA isolated by silica gel column chromatography was 32.3%. 相似文献
114.
Taro Suzuki Anatoly A. Tsygankov Jun Miyake Yutaka Tokiwa Yasuo Asada 《Biotechnology letters》1995,17(4):395-400
Summary Effect of pH of culture media on intracellular accumulation of poly-(hydroxybutyrate) (PHB) by a non-sulfur photosynthetic bacterium, Rhodobacter sphaeroides strain RV was studied in pH-stat cultures. Sub-optimal pH for growth, 8.0 or 8.5 gave the higher content of PHB rather than optimal pH 7.5 for growth. These results show that growth and PHB accumulation of the bacteria can be controlled by pH of culture media. 相似文献
115.
Induction of a Nerve Growth Factor-Sensitive Kinase that Phosphorylates the DNA-Binding Domain of the Orphan Nuclear Receptor NGFI-B 总被引:2,自引:0,他引:2
Yoko Hirata Michael Whalin David D. Ginty Jun Xing Michael E. Greenberg †Jeffrey Milbrandt Gordon Guroff 《Journal of neurochemistry》1995,65(4):1780-1788
Abstract: Nerve growth factor (NGF) induces the synthesis and the phosphorylation of the orphan nuclear receptor NGFI-B in PC12 cells. Previous work has shown that phosphorylation, by protein kinase A, of a specific serine in the DNA-binding domain inhibits its binding to the NGFI-B response element. Also, cytoplasmic extracts from PC12 cells phosphorylate this serine, and phosphorylation is greater in extracts from cells treated with NGF. The present work describes the induction, identification, and partial purification of a kinase (termed NGFI-B kinase I) from PC12 cell extracts that catalyzes this phosphorylation. Phosphorylation of the DNA-binding domain with this purified preparation inhibits its binding to the NGFI-B response element. The kinase is rapidly activated by treatment of the cells with NGF, and the activation lasts for at least several hours. It also is activated by fibroblast growth factor and epidermal growth factor (EGF), but the activation by EGF is quite transient. The kinase requires Mg2+ but will use Mn2+ . The molecular mass of the kinase is 95–100 kDa, and it is different from protein kinase A, Fos kinase, or pp90 rsk . Comparison with a partially purified preparation of cyclic AMP response element-binding protein kinase, however, indicates that the two are either very similar or identical. 相似文献
116.
117.
R. Matsukawa Z. Dubinsky E. Kishimoto K. Masaki Y. Masuda T. Takeuchi M. Chihara Y. Yamamoto E. Niki I. Karube 《Journal of applied phycology》1997,9(1):29-35
The inhibition of lipid peroxidation and radical scavenging effects were studied to evaluate the antioxidant activity for
extracts of 17 species of seaweed. The antioxidant effect was evaluated by determination of lipoxygenase activity and by α,
α-diphenyl-β-picrylhydrazyl (DPPH) decolorization. Lipoxygenase activity was depressed in the presence of aqueous and ethanol
extracts of 4 algal species; Sargassum species had the highest antioxidant activity of all the species examined. The ethanol
extracts of one Sargassum species showed competitive inhibition with the substrate. The same species also showed radical scavenging
activity in the DPPH decolorization test. Comparison of these results shows no relationship between enzyme inhibition and
radical scavenging activity.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
118.
Changes in eicosapentaenoic acid content of Navicula saprophila, Rhodomonas salina and Nitzschia sp. under mixotrophic conditions 总被引:4,自引:0,他引:4
Three species of microalgae able to produce eicosapentaenoic acid(EPA) were collected from brackish and sea water around Japan.
The species were identified as Navicula saprophila, Rhodomonassalina and Nitzschia sp. EPA as a proportion of total fatty
acids increased in the presence of acetic acid for Rhodomonas salina and Nitzschia sp. However, Navicula saprophila displayed
the greatest productivity of EPA and the EPA content of its biomass was enhanced under mixotrophic conditions in the presence
of acetic acid.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
119.
在体外系统中,发现超氧化物歧化酶(SOD)具有切割超螺旋DNA的活性. 猪血和牛血Cu/Zn-SOD以及烟草Mn-SOD都能将超螺旋DNA转变为非超螺旋结构的缺刻环状DNA,进一步产生线状DNA. 它们只作用于超螺旋DNA而不作用于线状DNA. 这个事实排除了SOD样品中污染核酸酶的可能性. 用H2O2、胍基抑制或蛋白酶降解的实验结果表明,这两种酶的活性中心处于酶蛋白的不同部位. 相似文献
120.
生物实验数据的某些非线性分析方法 总被引:2,自引:0,他引:2
简要介绍常用的非线性动力学参量,结合生物学实验数据的特点,给出几种最新的分析方法. 相似文献