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51.
C. Verderio S. Coco E. Pravettoni A. Bacci M. Matteoli 《Cellular and molecular life sciences : CMLS》1999,55(11):1448-1462
Hippocampal cultures offer unique advantages for the study of neuronal development and synaptogenesis. Studies performed
on this model enabled dissection of the temporal sequence of events which lead to the differentiation of pre- and postsynaptic
compartments.
Received 27 January 1999; received after revision 4 March 1999; accepted 5 March 1999 相似文献
52.
Olfactory receptors 总被引:1,自引:0,他引:1
Olfaction is an ancient sensory system allowing an organism to detect chemicals in its environment. The first step in odor transduction is mediated by binding odorants to olfactory receptors (ORs) which belong to the heptahelical G-protein-coupled receptor (GPCR) superfamily. Mammalian ORs are disposed in clusters on virtually all chromosomes. They are encoded by the largest multigene family (1000 members) in the genome of mammals and Caenorhabditis elegans, whereas Drosophila contains only 60 genes. Each OR specifically recognizes a set of odorous molecules that share common molecular features. In mammals, signal transduces through the G-protein-dependent signal pathway in the olfactory sensory neurons that synapse ultimately in the glomeruli of the olfactory bulb, and is finally processed in higher brain structures. The expression of a given OR conditions neuron and glomerulus choices. To date, the processes which monitor OR expression and axon wiring have emerged but are not completely elucidated.Received 9 July 2003; reiceived after revision 3 Ocotober 2003; accepted 22 Ocotober 2003 相似文献
53.
采用了一种HMM(隐马尔可夫模型 )的方法用于G蛋白偶联受体超家族层次各类别之间进行识别 ,具体考虑了ACDE与B类超家族 ,以及BCDE与A类超家族的分辨 ,取得了不错的效果 ,类之间的识别准确率可以达到10 0 % .研究过程中 ,考虑了G蛋白偶联受体一级结构信息和数据自身特性 ,合理地利用了G蛋白偶联受体一级结构序列的不等长特性 ,同时在模型的预测方面采用了双模型的预测机制 . 相似文献
54.
棉花凝集素对枯萎病菌的抑制作用与其受体的研究 总被引:4,自引:0,他引:4
研究了FITC或HRP标记的棉花凝集与枯萎病菌丝体作用后,在荧光显微镜下或扫描电镜下可以清晰地看到FITC-凝集素或HRP-凝集素-受体复合物在菌丝体上的均匀分布实验表明,纯化的棉花凝集素对棉花枯萎病菌丝体的生长有较强的抑制作用,当凝集素浓度达150μg/mL时,可以使枯萎病菌丝体的生长完全停止。 相似文献
55.
Con A的圆二色性谱与生物活性的研究 总被引:1,自引:0,他引:1
研究了不同温度、PH和不同脲浓度对Con A的CD谱和凝集兔红细胞活性的影响。 相似文献
56.
从16种蔬菜中筛选凝集素的研究 总被引:2,自引:2,他引:2
对福建省常见的16种蔬菜进行了凝集素的筛选实验。研究结果表明,花椰菜(Brassica oleracea var.botrytis L.)的花蕊和分葱(Allium schoenoprasum L.)、韭菜(Allium tuberosurn Rottler.ex Spreng.)的叶片组织中存在着凝集兔红细胞的凝集素。检测了这些蔬菜凝集素的热稳定性、硫酸铵沉淀和糖抑制作用,为它们的分离和纯化提供了一些科学依据。 相似文献
57.
Excitatory effect of histamine on neuronal activity of rat cerebellar fastigial nucleus in vitro 总被引:1,自引:0,他引:1
TANG Biao ZHANG Jun LI HongZhao ZHU JingNing & WANG JianJun Department of Biological Science Technology/State Key Laboratory of Pharmaceutical Biotechnology School of Life Sciences Nanjing University Nanjing China Jiangsu Key Laboratory for Bioresource Technology School of Life Sciences Nanjing Normal University Nanjing China 《科学通报(英文版)》2007,52(4):497-503
The cerebellar fastigial nucleus (FN) holds an important role in motor control and body balance. Previous studies have revealed that the nucleus is innervated by direct hypothalamocerebellar histaminergic fibers. However, the functional role of histaminergic projection in cerebellar FN has never been established. In this study, we investigated the effect of histamine on neuronal firing of cerebellar FN by using slice preparations. Sixty-five FN cells were recorded from 47 cerebellar slices, and a vast majority of the cells responded to histamine stimulation with an excitatory response (58/65, 89.2%). Perfusing slices with low-Ca2 /high-Mg2 medium did not block the histamine-induced excitation (n=10), supporting a direct postsynaptic action of histamine on the cells. Furthermore, the excitatory effect of histamine on FN neurons was not blocked by selective histamine H1 receptor antagonist triprolidine (n=15) or chlorpheniramine (n=10), but was effectively suppressed by ranitidine (n=15), a highly selective histamine H2 receptor antagonist. On the other hand, highly selective histamine H2 receptor agonist dimaprit (n=20) instead of histamine H1 receptor agonist 2-pyridylethylamine (n=16) mimicked the ex- citatory effect of histamine on FN neurons. The dimaprit-induced FN neuronal excitation was effectively antagonized by selective histamine H2 receptor antagonist ranitidine (n=13) but not influenced by se- lective histamine H1 receptor antagonist triprolidine (n=15). These results demonstrate that histamine excites cerebellar FN cells via the histamine H2 receptor mechanism and suggest that the hypotha- lamocerebellar histaminergic fibers may modulate cerebellar FN-mediated sensorimotor integration through their excitatory innervations on FN neurons. 相似文献
58.
59.
谷氨酸及其受体与运动 总被引:2,自引:0,他引:2
谷氨酸是中枢神经系统中主要的兴奋性神经递质,它的变化与运动性中枢疲劳的产生有密切的联系.谷氨酸是通过谷氨酸受体传递兴奋性信息的,谷氨酸受体是中枢神经系统主要的兴奋性神经受体,分为离子型受体与代谢型受体.谷氨酸受体在学习.记忆的形成、脑缺氧.缺血导致的病变及其它神经系统功能中扮演着重要的角色. 相似文献
60.
On day 3 of gestation ,one uterine horn of female pregnant mouse was injected intraluminally with 5 μL 0.1μg/mL lactacystin,a specific inhibitor of ubiquitin-pro-teasome pathway (UPP),while the contralateral horn served as control ,Animals were sacrificed by cervical dislocation on day 5,6,7 of gestation ,respectively,Then the number of implanted embryos in each uterine horn was calcuated,and the expression of VEGF and its receptors was examined,The data showed that the number of implanted embryos was decreased significantly after treatment with lactacystin ,The results of RT-PCR and Western blot indicated that expression of VEGF and its receptors at mRNA and protein levels was significantly decreased in the treated uterus,menawhile,the expression of HIF-1α(the α subunit of HIF ,a transcrip-tional factor of VEGF) was reduced at both mRNA and protein levels,These data suggested that the effect of UPP on VEGF expression was realized through regulating HIF-1α expression .In addition ,UPP is likely to take part in the modulation of VEGF receptors expression ,These changes may be one of the reasons for the reduction of implanted embryos. 相似文献