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54.
P F Maness 《Journal of neuroscience research》1986,16(1):127-139
The advent of recombinant DNA technology has led to the identification in the DNA of normal animal cells of over 30 proto-oncogenes that are homologous to retroviral transforming genes. One of these encodes a protein kinase (pp60c-src) of unknown function, that is preferentially synthesized in brain and neural retina. Here the expression of pp60c-src in the peripheral nervous system was examined in sensory neurons from chick dorsal root ganglia with antisera raised against the transforming protein of Rous sarcoma virus (pp60v-src) expressed in Escherichia coli carrying the cloned v-src gene. This antiserum recognizes pp60c-src specifically in normal chicken cells. Western immunoblotting showed that dorsal root ganglia of stage 30 (day 6.5) chick embryos contained elevated levels of pp60c-src. Immunoperoxidase staining of neuron-enriched cultures prepared from chick dorsal root ganglia showed pp60c-src immunoreactivity in cells with neuronal morphology; flat, fibroblastic cells contained no detectable immunoreactivity. Indirect double immunofluorescence with pp60src antibodies and monoclonal antibodies against the 200-kD subunit of neurofilament protein confirmed that the cells expressing pp60c-src were neurons. Ninety-six percent of the neurofilament-positive cells were immunoreactive with pp60src antibodies, and conversely, all pp60c-src-positive cells were immunoreactive with neurofilament antibodies. pp60c-src immunofluorescence appeared to be distributed over the cell body, processes, and growth cones. These results clearly demonstrate that pp60c-src is a product of neurons and is expressed in sensory neurons in culture. 相似文献
55.
ALVARO MARTÍNEZ DEL POZO MARIA GASSET MERCEDES O
ADERRA JOS G. GAVILANES 《Chemical biology & drug design》1989,34(5):416-422
α-Sarcin binds one Zn(II) cation per protein molecule, with a Kd value of 0.9 mM, determined by equilibrium dialysis experiments. Ca(II), Mg(II), and Mn(II) do not bind to α-sarcin. Cd(II) and Co(II) also behave as Zn(II). The binding produces local modifications on the protein conformation affecting the microenvironment of tryptophan residues. The three cations modify the fluorescence emission of the protein. The near-u. v. circular dichroism spectrum of the protein is also altered. The binding of Zn(II) and related cations does not modify the secondary structure of the protein. The ribonucleolytic activity of a-sarcin is inhibited upon Zn(II) binding, but no alteration of the ability of the protein to aggregate phospholipid vesicles has been observed. 相似文献
56.
目的探讨内源性热休克蛋白90(HSP90)在缺氧心肌细胞丝氨酸苏氨酸蛋白激酶(AKT)相关信号通路中的作用。方法建立新生Wistar大鼠心肌细胞缺氧模型,将细胞分为正常组、缺氧组、加入HSP90特异性阻断剂格尔德霉素后再缺氧组(格尔德霉素+缺氧组)。于缺氧后1、3、6、12、24、48h用噻唑蓝法检测心肌细胞的活力;缺氧24h,原位缺口末端标记法检测心肌细胞凋亡指数(AI);缺氧1、3、6、12、24h,蛋白质印迹法检测大鼠心肌细胞中内源性HSP90及AKT表达水平。结果(1)缺氧24、48h,缺氧组、格尔德霉素+缺氧组细胞活力均较正常组明显下降(P〈0.05);格尔德霉素+缺氧组细胞活力缺氧12h即开始明显下降,缺氧48h时明显低于缺氧组(P〈0.05)。(2)缺氧24h,缺氧组细胞AI为(10.7±1.2)%,明显高于正常组[(1.9±0.3)%.P〈0.05];格尔德霉素+缺氧组细胞AI为(26、3±5.3)%,明显高于缺氧组(P〈0.01)。(3)缺氧12h,缺氧组心肌细胞内源性HSP90及AKT表达水平高于正常组与格尔德霉素+缺氧组;缺氧24h,缺氧组有所下降.格尔德霉素+缺氧组则下降更明显。结论内源性HSP90对维持心肌细胞的活力有重要作用.缺氧心肌细胞AKT表达水平可受内源性HSP90表达水平的影响。 相似文献
57.
PRO 1000 V3型心电监护仪LCD逆变器的升级及注意事项 总被引:1,自引:0,他引:1
介绍了该型心电监护仪黑屏故障的常见原因,对升级前后的LCD逆变器电路作了对比分析,并详细介绍了升级更换的方法和注意事项。 相似文献
58.
Giorgio Ciprandi Mara De Amici Simone Negrini Gianluigi Marseglia Maria Angela Tosca 《International immunopharmacology》2009,9(10):1247-1249
Two new T cell subsets may be involved in allergic rhinitis (AR) pathogenesis: Th17 and T regulatory cells, mainly producing IL-17 and TGF-β respectively. Successful Sublingual Immunotherapy (SLIT) induces relevant immunological changes, thus the aim of this study was to evaluate serum IL-17 and TGF-β levels in AR patients treated with SLIT for 2 years. Patients' blood samples were collected before initiating SLIT (baseline), three months after the end of the first pre-seasonal SLIT course, and at the end of the second pre-seasonal course. IL-17 was detectable only in the most severe allergic patients. SLIT significantly induced an increase in serum TGF-β levels. There was moreover a significant relationship between TGF-β and symptom severity and drug use at the end of the study. Therefore, this study provides clinically relevant evidence that two pre-seasonal SLIT courses may significantly affect serum TGF-β levels. 相似文献
59.
螺旋CT三维重建成像在先天性高肩胛症手术方式选择中的作用 总被引:4,自引:2,他引:2
[目的]探讨螺旋CT三维重建技术在先天性高肩胛症分度和手术方式选择中的作用。[方法]22例先天性高肩胛症术前应用螺旋CT对病变部位进行扫描并三维重建,测量以肩胛骨肩胛冈内侧缘为参照点,两侧肩胛骨高度差。根据测量结果依据Cavendish分度将其分类,并根据三维重建成像选择不同的矫形手术术式。[结果]本组22例病人,随访2—4年,外观及功能均有不同程度的改善,未出现神经、血管和椎体等的损伤。[结论]根据螺旋CT扫描和三维重建检查结果,术前即可直观的明确先天性高肩胛症的病变程度,相互关系,伴发畸形,患侧肩胛骨与正常对侧肩胛骨的外观差异等,便于手术操作方案的制定,避免了手术操作的盲目性,减少医源性并发症的发生。 相似文献
60.
Terry Joe Sprinkle Julia F. Agee Russell B. Tippins C. Richard Chamberlain Guy B. Faguet George H. DeVries 《Brain research》1987,426(2):349-357
Monoclonal antibodies against human and bovine 2′:3′-cyclic nucleotide 3′-phosphodiesterase (CNPase) were generated by fusing FOX-NY myeloma cells with spleen cells from RBF/Dn mice previously immunized with the purified brain antigens. The enzyme isolated from bovine brain was quite basic, with an isoelectric point of 9.71 and both the bovine and human enzymes consisted of a closely spaced doublet at approximately 44 and 46 kDa on SDS-PAGE. Six monoclonals were identified as strongly recognizing the enzyme on both ELISA plates and on immunoblots of whole brain protein. Four monoclonals very weakly cross-reacted with guinea pig myelin basic protein. In contrast with two previous reports, some of our monoclonal antibodies did immunostain 2 or 3 protein bands in peripheral nerve, two bands closely corresponding to those immunostained in central nervous system (CNS) myelin, the Wolfgram protein fraction and in acetone powders of whole brain. Each of the 6 monoclonals reacting strongly on immunoblots recognized the enzyme in from 2 to 5 of the species examined (human, bovine, rat, mouse and rabbit). In addition, all 6 monoclonals that immunostained the enzyme in whole brain, myelin and Wolfgram protein immunoblots recognized both CNP1 (44 kDa) and CNP2 (46 kDa). The two closely spaced protein bands observed on SDS-PAGE and previously stained on immunoblots of CNS CNPase using polyvalent rabbit anti-bovine CNPase antisera, and now different monoclonal antibodies, appear to be immunologically related and to contain highly conserved sequences. 相似文献