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拉曼被孢霉F5发酵生产γ—亚麻酸的实验研究 总被引:2,自引:0,他引:2
对拉曼被孢霉突变株F5发酵生产γ-亚麻酸的最适碳源,氮源,发酵时间及湿度,无机盐离子的添加,最适碳源浓度及补加碳源时间等发酵条件进行了研究探讨,最适发酵培养基组成为(g/L):葡萄糖100,酵母浸出粉4,蛋白胨1,K2HPO41,CaCl2 1*10^-2,MgSO4 5*10^-2,FeSO4 1*10^-2,ZnSO4 7.5*10^-3,CuSO40.5*10^-3,MnSO4 2*10^-3,pH6.0,培养湿度为25度,140rpm 振荡培养10天,培养8天后(即收获前2天)补加5%葡萄糖,发酵结果为:DC24.59 g/L,TL10.84g/L,TL/DC 44.09%,GLA/TL10.67%,GLA产量为1156.63mg/L,GLA产量较初始结果提高156.15%,该菌株已达到工业化生产菌株要求。 相似文献
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Hedgehog (Hh) signaling plays an important role in embryonic patterning and adult stem cell renewal but has recently been found also to be involved in certain stem cell cancers. One of the first steps in Hh signaling is the autoprocessing of Hh protein, in which the C-terminal domain (Hh-C) catalyzes a cholesterol-dependent autocleavage reaction that leads to the production of the cholesterol ester of the N-terminal Hh domain (Hh-N), thereby yielding a signaling molecule that activates the Hh pathway by binding to the Patched receptor. This article describes an in vitro, homogeneous assay system that measures changes in fluorescence polarization that accompany the cholesterol-dependent autocleavage of Hh protein. The assay system makes use of a modified Hh protein in which Hh-N, which is not essential for autocleavage, is replaced by a 25-residue peptide containing a tetracysteine motif, complexed with a bisarsenical fluorophore. The assay is quite robust and easily adapted to high-throughput screening in 384-well plates with Z' factors above 0.8. It has been used to screen the National Institutes of Health Clinical Collection, which has led to the identification of 2 compounds that inhibit the cholesterol-dependent autocleavage of Hh protein at micromolar concentrations. 相似文献
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目的:探讨冠心病(CAD)患者血清C-反应蛋白(CRP)的变化及其临床意义.方法:运用全自动生化分析仪检测97例CAD患者和28例对照组人群的血清CRP,将CAD患者进一步分为稳定性心绞痛组(SAP)、不稳定心绞痛(UAP)、心肌梗死组(AMI)三组.另外,将97例CAD惠者分为1支病变组、2支病变组和3支病变组.所有研究对象均行选择性冠状动脉造影检查.结果:(1)与对照组比较,CAD患者血清CRP显著升高(P<0.05);(2)与对照组比较,SAP组、UAP组和AMI组患者血清CRP均显著升高(P<0.05);与SAP组比较,UAP组和AMI组患者血清CRP亦显著升高(P<0.05);(3)与对照组比较,1支病变组、2支病变组和3支病变组患者血清CRP均显著升高(P<0.05);与1支病变组比较,2支病变组和3支病变组患者血清CRP亦显著升高(P<0.05);与2支病变组比较,3支病变组患者血清CRP亦显著升高(P<0.05).结论:(1)CRP可能与CAD有关;(2)CRP异常升高可能反映冠状动脉斑块的不稳定和CAD的严重程度. 相似文献
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目的:探讨普伐他汀对醛固酮诱导新生大鼠心脏成纤维细胞转化生长因子-β1(TGF-β1)的影响。方法:采用胰酶消化法和差速贴壁分离法获取和培养心脏成纤维细胞,应用ELISA、Western-blot、RT-PCR的方法分别测定醛固酮、普伐他汀以及甲羟戊酸对心脏成纤维细胞培养液中TGF-β1水平和心脏成纤维细胞TGF-β1mRNA和蛋白质的表达。结果:与正常对照组相比,醛固酮(10-7mol/L)可促进心脏成纤维细胞培养液中TGF-β1水平和心脏成纤维细胞TGFβ-1mRNA和蛋白质的表达,提前给予普伐他汀(10-5,10-4,10-3mol/L)能剂量依赖性地抑制醛固酮的上述作用,同时这种抑制作用可被甲羟戊酸所逆转。结论:普伐他汀可抑制醛固酮诱导的心脏成纤维细胞TGF-β1mRNA表达以及蛋白质的合成和分泌,其机制可能与甲羟戊酸代谢途径有关。 相似文献
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应用热扩散法测定香蕉树蒸腾速率 总被引:6,自引:4,他引:2
香蕉树植株高大,一般采用间接方法确定耗水量,但所得结果受土壤、大气和农艺措施等因素的影响较大.本文于2005年11月15日—12月5日在温室内采用热扩散法(即Granier法)测定香蕉树的茎液流,并与用数字天平(称重法)测定的香蕉树蒸腾速率进行对比试验. 结果表明,Granier法测定的日茎液流量与称重法测定的日蒸腾量相差4%.Granier法测定的茎液流速率一般滞后于称重法确定的蒸腾速率1 h左右.当日蒸腾量小于0.05 L·m-2(活性叶面积)时,Granier方法不能测定茎液流量.Granier传感器一般在安装2~3 d后即可正常工作,同时在多株植株上安装Granier传感器取其平均流速值计算蒸腾量可以明显减小测量误差. 相似文献
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为寻找一种生产周期短、分离效果好、易操作的纯化黄酮的方法,本研究利用黄酮与金属能形成络合物的性质,从反应体系溶剂、金属盐、解络合剂的添加量优化了络合法纯化银杏黄酮的工艺。结果表明,pH值对络合反应的发生及最终产品的性质具有很重要的影响。金属络合纯化法的最佳工艺条件为:以100 mL甲醇为溶剂,黄酮浓度为2.4 mg/mL,0.20 g硫酸锌为络合剂,反应溶液pH值为9.50,0.2 g EDTA为解络合剂,可以使银杏提取物中黄酮含量由24%提高到55%,得率为58%。 相似文献
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There were two forms of rhizobial bacteria present in infected host cells of nodules. One was bacteroids which were enclosed in peribacteroid membrane originated from the infected host cells. The other was rhizobia as vegetative cells. The infected host cells were occupied by most of the bacteroids and a certain number of the vegetative cells respectively. With the nodule senescence, there were two kinds of fate of the bacteria: The bacteroids degenerated togather with the infected host cells at the same time and further disintegrated completely, so it is not possible that the disintegrated bacteroids could be returned into soil to revive: the vegetative cells did not disintegrate and die when the infected host cells senesced, eventually could be turned back into soil. The vegetative cells may play an important role, on the one hand, in cycle between legume and soil, on the other hand, maintain rhizobia in natural balance of population ecosystem. 相似文献
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