关键词： caecotrophy   digestion   herbivory   nitrogen utilization   capybara, Hydrochaeris  

摘要： The capybara (Hydrochaeris hydrochaeris) is a hindgut fermenter whose digestive efficiency is comparable to that of ruminants on similar diets. It is an interesting case for study because it is the largest caecum fermenter and uses coprophagy as part of its digestive strategy. It practices coprophagy in the early morning and forages and defaecates in the evening. Its anatomy is well known but the limited information available about its digestive physiology has been obtained from captive animals. In this work we studied the capybara's digestive physiology, using microbial and chemical information from samples taken from wild capybaras in the early wet season in the morning (0600-0700 hours), noon (1200-1300 hours) and evening (1800-1900 hours), key points in the digestive cycle. Bacteria (cellulolytic and non-cellulolytic) and protozoa were present in high concentrations in the caecum and colon. There were no significant differences in nitrogen concentrations between digestive tract compartments in the coprophagy period (0600 hours), but in the other two periods nitrogen concentrations were significantly higher in the caecum than in the stomach and colon. This is suggestive of selective retention of microbial cells with fluid digesta in the caecum and of cecotrophy (the production of two distinctly different kinds of faeces - one kind called cecotrophes formed from caecal contents and ingested), The capybara hindgut (caecum and colon) with its content, was heavier during the dry season (period of poor diet quality) than in the wet season, but there were no significant seasonal differences between the stomach or small intestine and their contents. This suggests changes in the capacity of the hindgut, the site of microbial fermentation, related to seasonal variation in resource quality.

关键词： 颅顶慢电位   皮层诱发电位   神经生理学   动作电位   基础与临床   多发性脑梗塞痴呆   后电位   引导电极   兴奋性   突触  

摘要： 1、神经生理学基础 1.1.诱发电位的构成:诱发电位中主要由两种神经元电位构成,即动作电位与突触后电位。 1.1.1.动作电位:此主要由[Na^+]细胞外/[Na^+]细胞内值所决定的。动作电位传播到引导电极时,首先记录到一正性电位,阴极的动作电位向前传播达到引导电极时,则记录到负性电位,再除极继续向前传播并离开引导电极,则记录到另一个正性电位,即构成三相电位。

关键词： 个体差异   科学家   老年性痴呆   《千金要方》   生活习惯   诸葛亮   良好习惯   秦汉至明清   神经生理学   居住环境  

摘要： 俗话说:“勤劳是个宝,人生不可少。”“勤劳能健骨强身,懒惰则精神瘫痪。”每个人都应该保持经常活动,这是强身健脑的普通常识。 人生进入老年,究竟是清静休养好,还是勤奋些好呢?当然,人的个体差异很大,生活习惯、阅历不同,不能一概而论,基本上应保持原来的良好习惯,在力所能及的范围内,尽可能多动脑、多动手。生命在于运动。

关键词： tremor   electrophysiology   reflexes   diagnosis   time series analysis  

摘要： The neurophysiological analysis of tremor has a long tradition. These attempts were directed to understand the mechanisms underlying tremor, on the one hand, and to develop tools to better diagnose the different types of tremor, on the other. Meanwhile, reasonable criteria are available to distinguish between centrally and peripherally mediated tremors. However, no generally accepted means exist to differentiate the different forms of central tremors. Frequency is a useful classifier for cerebellar tremor, rubral tremor, and orthostatic tremor. Although the highest amplitudes are found in Parkinson's disease, this parameter does not well distinguish between the different tremors. Waveform analysis of tremor is a promising tool to separate between the different tremors. Polymyography is pathognomonic for some rare forms of tremor. New approaches to classify tremors are based on positron emission tomography scanning, analysis of ballistic movement, and reflex testing. The means to separate myoclonias from tremors include EEG/EMG correlation techniques, long-latency reflexes, and polymyography. Provided these techniques are applied in the setting of careful clinical analysis of tremor syndromes, they may prove to be helpful in clinical practice.

关键词： 第三信使   神经生理学   诱导   分子机制  

摘要： 第三信使的诱导及其分子机制朱和明，朱长庚（同济医科大学脑研究室，武汉４３００３０）细胞如何将外界信号转换成细胞应答反应是生命科学必须回答的一个重要问题。现已清楚跨细胞膜信息转递机制包括三个环节：受体识别、信号传递、细胞效应，在这一机制中具有信息传递功...

关键词： 迷走神经   背核   神经生理学  

摘要： 迷走神经背核（ＤＭＶ）是一个重要的内脏运动核团和内脏感觉核团。ＤＭＶ与中枢及外周存在广泛的纤维联系。ＤＭＶ和孤束核、最后区一起构成了“迷走感觉运动中枢”。ＤＭＶ存在神经－体液回路，使ＤＭＶ神经元可以直接感受外周血及脑脊液中的信息。ＤＭＶ含乙酰胆碱、儿茶酚胺、神经肽类等多种递质及相应受体。ＤＭＶ参与中枢调节胃肠、心血管及内分泌等生理功能。

关键词： 神经病   神经生理学   检查   呼吸系统疾病  

摘要： 临床神经生理学在呼吸系统中的应用卢祖能，汤晓芙许多疾病可影响呼吸功能。在危重病房中（ＩｎｔｅｎｓｉｖｅｃａｒｅｕｎｉｔＩＣＵ），绝大多数病人的病情危重，多需要辅助呼吸；许多需要插管呼吸机辅助通气。原发于气道、胸壁及肺部的疾病为常见的原因。然而，在相当...

关键词： 神经元   研究方法   计算机   高尔基技术   脑组织   放射自显影术   经细胞   中枢神经系统   神经生理学   工作原理  

摘要： 脑能否了解脑.对这一问题历来存在两种对立的观点.乐观者认为脑不过是机体的器官之一.如同心脏一样.仅管要花费巨大的代价.付了艰辛的努力,但最终还是可以了解脑的.另一种观点认为.了解脑如何工作得靠脑去执行.用脑去了解脑几乎是不可能的.正如一句名言“一个人是不可能靠自己的力量把自己举起来的”.但我们只要对当代脑研究的成就稍作了解.就会发现.这种比喻并不是非信不可的.

关键词： 神经病   神经生理学   检查   磁刺激技术   物理学  

摘要： 磁刺激技术在临床神经生理学的应用──第二部分磁电刺激的物理学和生理学基础卢祖能，汤晓芙一、概述从磁电刺激的历史发展可知，对神经系统电学特征的描述可追朔到一个世纪以前。从根本上讲，磁刺激器并非一项全新的技术，只是逐渐地从设备上进行了改良而已；而且这又是...