嗅觉神经系统的电位发放

利用描述抑制结构的WLC模型,数值分析嗅觉神经系统各个神经元的电位发放,得到嗅觉神经系统中球周细胞层、嗅球、僧帽细胞层、颗粒细胞层、前嗅核和前梨状皮层内各个神经元的电位发放,模拟了Freeman嗅觉系统各K系列模型的电位发放模式,数值说明僧帽细胞具有丰富的发放形式,神经元之间的具有两种信号传递模式,数值结果和嗅觉实验现象相吻合.     

风知道

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一辆购物车

双休日,我和妈妈去超市买一些生活用品。走进超市,性急的我一踏上电梯就往下冲,把妈妈落在身后。就在我兴奋地东张西望时,妈妈从电梯上下来了,告诉我家里没米了,让我找辆购物车推米。我立刻去电梯口找购物车。可是,今天的顾客好像很特别,手提篮不要,装了轮子和把手的手推篮也不要,偏偏要购物车。我把角落     

八肽胆囊收缩素(CCK-8)对抗电针镇痛及电针耐受机理的初步探讨

本文采用电生理学方法,以大鼠丘脑束旁核痛兴奋神经元(PEN)和痛抑制神经元(PIN)的电活动变化为才旨标,在细胞水平上研究八肽胆囊收缩素(CCK-8)与电针镇痛和电针耐受机理的关系.结果表明:电针大鼠“足三里”穴位可抑制PEN和兴奋PIN的电活动,产生镇痛效应;脑室注射CCK-8可取消电针对PEN和PIN放电的影响;而无硫CCK-8对呈现电针效应的PEN和PIN的电活动无影响.长时间电针(六小时)可使PEN和PIN的放电对再次电针无明显变化,亦即产生对电针镇痛的耐受效应.推测,内源性CCK-8可能参与电针耐受的形成.     

化学刺激引起相邻丽藻细胞的重复兴奋发放

给一丽藻细胞以化学刺激,经过一段延时,发现与之相邻的细胞的膜电位出现了自持重复兴奋发放.这一现象,可能是阳离子通过细胞节的扩散而引起的.     

论运动员过度训练的预防和消除

通过对运动训练中常见的“过度训练”的概念、症状、类型等问题的分析,从运动生理、心理及运动训练学角度研究过度训练产生的原因和机制,提出过度训练预防和消除的具体措施．     

Excitatory effect of histamine on neuronal activity of rat cerebellar fastigial nucleus Jn vitro

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 hletaminergic 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-Ca^2＋/high-Mg^2＋ 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 HI receptor agonist 2-pyridylethylamine （n=16） mimicked the excitatory 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 selective 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 hypothalamocerebellar histaminergic fibers may modulate cerebellar FN-mediated sensorimotor integration through their excitatory innervations on FN neurons.     

Iterative solutions for low lying excited states of a class of SchrSdinger equation

The convergent iterative procedure for solving the groundstate Schr?dinger equation is extended to derive the excitation energy and the wavefunction of the low-lying excited states. The method is applied to the one-dimensional quartic potential problem. The results show that the iterative solution converges rapidly when the coupling g is not too small.     

使物理学为之兴奋的奇异拓扑绝缘体

一篇致力于拓扑绝缘体研究的论文(#6)引发了不小的轰动,从而使本期物理学热点论文榜也因此火爆起来.这些特殊材料的体内大部分为绝缘体,而它们非凡的表面状况导致了新的物态,包括在表面上不受阻碍的单相电子流动.这种类型的材料允许电子在室温下能量不受损失地行进.有论文描述了这一新兴领域的发展,指出这些材料在凝聚态物理、纳米技术...     

小蘑菇的伪装计划

雨下在茂密的森林里,哗啦哗啦,好像在帮所有的花草树木淋浴。植物们满心欢喜地接受大自然的"恩赐",但动物们却纷纷走避。小蘑菇刚刚从湿软的树根底下探出头来,它兴奋地睁开眼睛看着周围的世界,水色碧绿……