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31.
鸡胚血液中原始生殖细胞的分离及其培养的研究 总被引:2,自引:0,他引:2
从孵化48~55小时鸡胚中抽取血液,每只胚胎可获血液2~6μl左右。一步法离心分离原始生殖细胞,可使其浓度由0.1%以下提高到50%以上。将多余血细胞用微量吸管移走后,加入添加10%胎牛血清的TCM—199做为培养基,37.5℃,5%CO2,95%空气,饱和湿度下培养,原始生殖细胞可成活24小时左右。 相似文献
32.
高压静电场处理沙棘插条生根状况的初步研究 总被引:2,自引:0,他引:2
用高压静电场处理沙棘插条研究生根状况,方法简便易于处理,该装置适于进行大规模的处理,从目前研究表明:高压静电场对沙棘插条有正刺激效应,并以电场强度为3.9kv/cm,时间为40分钟处理最佳。 相似文献
33.
中药固真方对一些与细胞增殖有关基因表达的影响姚明忠,顾文聪,丁卫,韩志芬,杜国光(上海中医药大学生物化学教研室,上海200032)(北京医科大学生物化学与分子生物学系,北京100083)中药固真方(VRF)具有补肾益精、延缓衰老的作用[1].能提高成... 相似文献
34.
Laminin and Neuropeptide Y Are Increased by Synapsin Transfection in Cultured NG108-15 Neuroblastoma/Glioma Hybrid Cells 总被引:2,自引:0,他引:2
† Gabriel Fried Hui Quan Han ‡Björn Meister ‡Tomas Hökfelt Paul Greengard 《Journal of neurochemistry》1995,64(6):2674-2680
Abstract: We have investigated the presence and expression of laminin and neuropeptide Y (NPY) in several NG108-15 cell lines transfected with synapsin Ib, IIa, or IIb. The content of laminin, a basal membrane glycoprotein that promotes adhesion and induces neurite outgrowth and neuronal differentiation, was increased in all transfected cell lines examined. In cells that were chemically differentiated with prostaglandin E1 plus 3-isobutyl-1-methylxanthine, laminin levels were increased even further. The content of NPY, suggested to be a neurotransmitter/neuromodulator in peripheral sympathetic neurons as well as in central neurons, was also increased in all transfected cell lines examined. Immunohistochemical analysis combined with confocal laser microscopy showed that NPY staining was granular and very often enriched in neuritic varicosities. The distribution and the staining pattern of NPY were consistent with storage of NPY in large dense-cored vesicles. The results indicate that, in differentiated neurons, the synapsins increase the levels of a neuropeptide transmitter stored in large dense-cored vesicles and of an extracellular matrix protein associated with neuronal maturation. 相似文献
35.
A human protein selected for interference with Ras function interacts directly with Ras and competes with Raf1. 总被引:13,自引:8,他引:5 下载免费PDF全文
The overexpression of some human proteins can cause interference with the Ras signal transduction pathway in the yeast Saccharomyces cerevisiae. The functional block is located at the level of the effector itself, since these proteins do not suppress activating mutations further downstream in the same pathway. We now demonstrate, with in vivo and in vitro experiments, that the protein encoded by one human cDNA (clone 99) can interact directly with yeast Ras2p and with human H-Ras protein, and we have named this gene rin1 (Ras interaction/interference). The interaction between Ras and Rin1 is enhanced when Ras is bound to GTP. Rin1 is not able to interact with either an effector mutant or a dominant negative mutant of H-Ras. Thus, Rin1 displays a human H-Ras interaction profile that is the same as that seen for Raf1 and yeast adenylyl cyclase, two known effectors of Ras. Moreover, Raf1 directly competes with Rin1 for binding to H-Ras in vitro. Unlike Raf1, however, the Rin1 protein resides primarily at the plasma membrane, where H-Ras is localized. These data are consistent with Rin1 functioning in mammalian cells as an effector or regulator of H-Ras. 相似文献
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37.
The cellular immune response (MIF, E-rosette formation and changes in nucleolar morphology of lymphocytes) was followed as
related to age and antigenic stimulation. MIF in healthy infants increased from the 2nd to the 12th week of life as compared
with the first week, probably due to BCG vaccination. The total and active E-rosette formation did not change during the whole
period of investigation. Ring-shaped nucleoli increased gradually from the second week of life. Active nucleoli increased
up to the 4th week,i.e. after BCG vaccination and then slowly decreased. Micronucleoli being high in the first week, decreased during 24 weeks of
life. After artificial colonization of the intestine the production of MIF was slightly lower in colonized infants than in
controls from the 2nd to the 12th week. The other parameters followed were not influenced by colonization. 相似文献
38.
39.
The crystal structure of cholestanyl n-octanoate (caprylate) (C35H62O2) is monoclinic with space group A2 and cell dimensions a = 10.103(7), b = 7.646(7), c = 87.63(7) A, beta = 90.51(6) degrees; Z = 8 [two molecules (A, B) in asymmetric unit], V = 6769 A3, Dc = 1.010 g cm-3. Integrated X-ray intensities for 3798 reflections with I greater than 2 sigma (I) were measured with a rotating anode diffractometer at room temperature. The structure was determined using direct methods. Block diagonal least squares refinement gave R = 0.111. Molecules A and B have almost fully extended conformations, but differ significantly in the rotation about the ester bond and in the C17 chains. The molecular packing in the crystal structure of cholestanyl caprylate consists of stacked bilayers each having d002 = 43.8 A in thickness and within each bilayer, cholestanols pack with cholestanols and caprylate chains pack with caprylate chains. The crystal structure is very similar to that of cholesteryl myristate but is quite different from that of cholesteryl caprylate. The phase equilibria of the cholestanyl caprylate/cholesteryl caprylate binary system have been shown to involve limited mutual solubility of the two components and to have a eutectic point at 73% cholestanyl caprylate. The cholesteric mesophase is monotropic at all compositions except for a narrow range near the eutectic point where it is enantiotropic. 相似文献
40.