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31.
不同季节银木叶精油化学成分的研究 总被引:1,自引:0,他引:1
黄远征;温鸣章;肖顺昌;赵蕙;任维俭 《武汉植物学研究》1988,6(3):253-259
用毛细管气相色谱-质谱-计算机联用技术、毛细管气相色谱双柱保留指数法和双柱标准品叠加法分析了不同季节银木叶精油化学成分。从分离出来的207—250个色谱峰中,初步鉴定出59个成分,被鉴定成分的总量占精油总组成的94.45—98.92%,其主要成分随采油季节不同而有所不同。 相似文献
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本文用凝胶直读法、末端鉴定法等相配合,测定了樗蚕(Philosamia cynthia)絲腺5SrRNA的核苷酸顺序:AGACAACGUCCAUACCACGUUGAAAACACCGGUUCUCGUCCGAUCACCGAAGUCAAGCAACGUCGGGCGCGGUCAGUACUUGGAUGGGUGACCGCCUGGGAACACCGCGUGCUGUUGGCUU比较了樗蚕、蓖麻蚕、柞蚕、家蚕、果蝇等5SrRNA结构差异,在分子水平上探讨了昆虫的分化。 相似文献
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猪肺炎支原体膜上ATP酶为Mg~(2+)激活,乌巴因不抑制。DCCD和寡霉素对该酶也无抑制作用,只有NBD与Quercetin才有一定的抑制效果。用梯度凝胶电泳可获均一的具有活性的酶蛋白带。 相似文献
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Expression of c-myc protooncogene in rat lens cells during development,maturation and reversal of galactose cataracts 总被引:2,自引:0,他引:2
Yi Wen Songtao Shu Nalin J. Unakar Isaac Bekhor 《Molecular and cellular biochemistry》1992,112(1):73-79
It is well established that normal patterns of epithelial cell proliferation and metabolism, and of fiber cell differentiation and maturation are essential for the maintenance of transparency in the ocular lens. Several factors, including exposure to high levels of sugars, have been known to result in the compromise of lens transparency. For example, initiation of lens cell damage by galactose induces lens epithelial cells to proliferate. Elevated levels of c-myc mRNA have usually been correlated with rapid cell growth and increased entry of cells into the S phase. Therefore, changes in c-myc mRNA levels may provide an early indication of the stimulation of lens epithelial cells to proliferate and differentiate, which has been postulated to be an early and important event in response to lens cell injury by galactose. By Northern blot hybridization analysis we quantitated c-myc mRNA levels in the lens capsule epithelia of rats (1) exposed to galactose, and (2) undergoing a partial recovery from the galactose-induced cell damage. At the onset of lens cell damage, we find c-myc mRNA to elevate to 6-fold by 24 hr, and by 48 hr decreases to about 3-fold the normal levels. During recovery, c-myc mRNA continues to be expressed at high levels approaching a 10-fold increase by day 12, then decreasing to levels of about 8-fold the control by day 30. The 24 h transitory elevation in c-myc mRNA in lens epithelial cells is in accord with our previous observations on the 24 h increase in MP26, crystallin and aldose reductase mRNAs following a high influx of galactose. Therefore, the elevation in c-myc mRNA as well suggest that galactose appears to cause lens cells to undergo an early transitory period of gene induction following the exposure of lens cells to galactose. 相似文献
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Dr. Jian Wen Chen Lanping Zhang Jiantao Song Fen Hwang Qinghua Dong Jian Liu Yumin Qian 《Current microbiology》1992,24(4):189-192
The glycoproteins and glycolipids from membranes of virulent strain Z and avirulent strain M ofMycoplasma hyopneumoniae have been compared. The proteins and the glycoproteins were identified by SDS-polyacrylamide gel electrophoresis and concanavalin A-biotin labeling, respectively. The membrane preparation contained approximately 34 protein bands with molecular weights between 20 KD and 100 KD. The concanavalin A-biotin system reacted with a glycoprotein of a molecular weight of approximately 28,000 from avirulent strain M and did not react with the correspondent band from virulent strain Z. The membrane glycolipids of both strains consisted of monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG), and the percentages of 160, 180, and 181 fatty acids comprised more than 80% of the total fatty acids of membrane glycolipids. The 180 fatty acid of MGDG in avirulent strain M was twofold higher than that of virulent strain Z. 相似文献
40.
Hematopoietic cell phosphatase (Hcph) was identified by amplification of conserved protein tyrosine phosphatase sequences from a myeloid cell line and is predominantly expressed in hematopoietic cells. Hcph is unique in containing two, tandemly repeated, src-homology 2 domains in the amino terminal region of the phosphatase. Using a genomic probe in interspecific backcross analysis, the murine Hcph gene maps to mouse Chromosome 6 and is tightly linked to the Tnfr-2 and Ly-4 genes. 相似文献