频域脑导纳图的实用价值研究

应用KT—ENG型双侧脑血流自动检测仪,测量多例头部电导纳图的功率谱,并进行了对比分析．结果显示不同的频域脑导纳图,其功率中的某些指标有显著性差异（P〈0．05）．     

基于多导脑电特征的生理性精神疲劳分析

通过对4种生理性精神疲劳状态下4导脑电信号进行功率谱和小波熵特征分析，研究了脑电信号各节律相对功率以及小波熵与生理性精神疲劳程度之间的关系，并分析了它们在不同生理性精神疲劳状态下的变化规律及其相关性．实验分析结果表明，脑电信号各节律的相对功率以及小波熵平均值与生理性精神疲劳程度之间存在很强的关联性，对于不同的生理性精神疲劳状态，随着生理性精神疲劳程度的增加，其脑电信号的小波熵平均值逐渐降低，θ、α和β节律高频快波相对功率的平均值逐渐降低，而占节律高幅度慢波相对功率平均值逐渐增加．脑电信号各节律的相对功率以及小波熵平均值有望成为衡量生理性精神疲劳程度的指标．     

老年痴呆脑电能谱分布特征

比较分析了老年痴呆患者与正常老人在安静闭目时的脑电功率谱能量分布特征，以探索老年患者脑电诊断的新途径．运用高分辨AR谱和小波变换进行脑电的功率谱分析，将信号分解到不同频段并提取其特征能量，得到脑电的能量分布．初步表明，老年疾呆患者脑电能量在中高频段d(8～16Hz)显著降低(严重时可低至正常人的5％)，而在低频段6(0～4Hz)的能量却明显偏高(可达正常人的几倍到几十倍)，该结果提示：可考虑试用脑电能谱分布特征作为老年痴呆临床工程诊断的特异性指标．     

基于EEG与EOG信号的疲劳驾驶状态综合分析

疲劳驾驶时,司机的脑电信号和眼电信号特征均发生显著变化,本文针对这两类信号进行分析研究,利用这两类数据综合分析判断司机是否处于疲劳驾驶状态.首先对采集的脑电信号进行小波包分解,提取信号中的α波,并计算其相对功率谱P;然后利用Pearson相关系数分析两路对称导联F7,F8中眨眼信号特征,去除干扰;最后利用BP神经元网络对眨眼信号进行识别,计算眨眼频率.结果表明,利用眼电信号和脑电信号特征综合分析司机眨眼动作,能准确识别出眨眼信号,并能正确检测人的驾驶疲劳状态的变化.     

基于EEG与EOG信号的疲劳驾驶状态综合分析

疲劳驾驶时,司机的脑电信号和眼电信号特征均发生显著变化,本文针对这两类信号进行分析研究,利用这两类数据综合分析判断司机是否处于疲劳驾驶状态.首先对采集的脑电信号进行小波包分解,提取信号中的α波,并计算其相对功率谱P;然后利用Pearson相关系数分析两路对称导联F7,F8中眨眼信号特征,去除干扰;最后利用BP神经元网络对眨眼信号进行识别,计算眨眼频率.结果表明,利用眼电信号和脑电信号特征综合分析司机眨眼动作,能准确识别出眨眼信号,并能正确检测人的驾驶疲劳状态的变化.     

不同年龄组的视动性眼震在摄影眼震图中的表现

目的：为了解在摄影眼震图（ Ｖ Ｏ Ｇ） 中,年龄的增长对视动性眼震（ Ｏ Ｋ Ｎ） 的影响。方法：将９９ 名前庭功能正常的自愿者按不同年龄分３ 组,用 Ｖ Ｏ Ｇ 进行 Ｏ Ｋ Ｎ 检查,通过刺激整个视网膜所诱发的视动性眼震,用 Ｖ Ｏ Ｇ 记录。条纹刺激速度分别为２０ 、３５ 、５０（°）／ｓ,定量参数是“ｇａｉｎ”（ 眼球运动速度与刺激条纹速度的比值） 。结果：第１ 组和第２ 组间ｇａｉｎ 值无统计学差异,但第３ 组在刺激速度达５０（°）／ｓ 时,视动性眼震ｇａｉｎ 值明显下降。结论：临床上分析视动性眼震的结果时,必须考虑年龄这一因素。     

SIR－1型短红外发射理疗器对脑血管的作用效应

以６０名大学生和２１例头晕、头痛患者为实验对象，通过实验前与实验后的脑血流图检测资料的分析、对比，验证ＳＩＲ—１型短红外发射理疗器对脑血管的作用效应．结果表明，实验者经本理疗器对头部作用２０ｍｉｎ后，可出现脑血管扩张、紧张度降低、阻力减小、流入时间缩短、流入容积速度变大等现象，对脑血管起着良好作用．头晕、头痛患者经本理疗器对头部和有关穴位作用２０ｍｉｎ后，感觉舒服，症状缓解、减轻；经过连续数次的作用、治疗之后，改善了脑的血液循环，对稳定和调节脑血流量有良好效应，取得满意的近期疗效，有效率达８５．７％．     

前庭内侧核对胃酸分泌及呼吸和心率的影响

利用Wistar雄性大鼠,研究麻醉状态下电刺激大鼠前庭内侧核对其胃酸分泌、呼吸频率和心率的影响。用灌流法收集胃液,比较电刺激前庭内侧核前后胃酸分泌量的变化,同时记录心电图和呼吸频率。结果显示,电刺激过程中以及刺激结束后的胃酸分泌量与刺激前相比均无显著性变化(p>0.05);刺激过程中呼吸频率和心率均明显增加(p<0.05)。大鼠前庭内侧核的兴奋引起呼吸频率和心率的显著改变,但不引起胃酸分泌的变化,原因可能与大鼠无呕吐中枢有关。     

脑血流图的新进展

脑血流图，可能为医学领域提供了一种新的激动人心的治疗手段。本书收录的论文涵盖了以下几方面的内容：对成像技术的解释；对脑血流图正确性和可靠性的检查；对脑血流图诸多应用的描述；显示了在临床医生常见的多种中枢神经症状中脑血流图是如何得到应用的，这是最重要的一点。     

大鼠前庭脊核经脑桥核接替向旁绒球的间接投射

探讨大鼠前庭脊核经脑桥核接替后向小脑旁绒球投射的间接通路,为揭示眼平稳跟踪运动的调控机制提供形态学基础.应用顺、逆行追踪结合偏离垂直轴旋转刺激激发脑内相关神经元Fos表达的方法,观察前庭脊核向脑桥核投射的顺行标记纤维与脑桥核内向小脑旁绒球投射的神经元是否有重叠.在脑桥外侧核发现前庭脊核投射来的纤维及终末与Fos/荧光金双重标记细胞有重叠.大鼠脑内存在前庭脊核经脑桥外侧核中继后投射至小脑旁绒球的间接通路.该通路有传递直线变速运动信号的作用,可能是眼平稳跟踪运动的调控途径之一.     

电刺激大鼠前庭神经内侧核对胃运动、呼吸运动和心率的影响

利用Wistar雄性大鼠,研究了前庭神经内侧核的兴奋对胃运动、呼吸运动及心率的影响．利用核团电刺激方法对大鼠前庭神经内侧核进行刺激,测定该刺激对大鼠胃运动、呼吸频率及心率形成的影响．刺激参数为：波宽0．3ms,强度0．2mA,频率30Hz;刺激位点为前囟后11．04mm,中线旁开1．2mm,露骨表面下7．5mm．电刺激中和刺激后的胃运动,与刺激前相比差异无统计学意义（P〉0．05）;在刺激过程中,呼吸频率和心率都有一定程度的增加,差异有统计学意义．心率在第一次刺激和第二次刺激过程中,与刺激前相比分别增加了3．5％（P〈0．05）和2．9％（P〈0．05）．呼吸频率在第一次刺激和第二次刺激过程中,刺激前相比分别增加了8．9％（P〈0．05）和8．2％（P〈0．05）．大鼠前庭内侧核兴奋引起心率和呼吸运动的显著改变,但不引起胃运动的变化．原因可能与大鼠无呕吐现象有关,有待继续研究．     

Effect of propolis on vestibular compensation following unilateral labyrinthectomy in rats

Unilateral labyrinthectomy (UL) results in the vestibular syndrome including nausea, vomiting, vertigo, spontaneous nystagmus (SN) and postural disturbance which abate over time in a process of behavioral recovery known as vestibular compensation. In order to investigate the effect of propolis on bestibular compensation, SN and expression of c-Fos protein in the medial vestibular nucleus (MVN) were measured in unilateral labyrinthectomized Sprague-Dawley rats with pretreatment of propolis.     

Insulin binds to brain blood vessels in vivo.

The brain has generally been considered an insulin-independent organ, because insulin does not apparently exert a direct effect on brain glucose consumption. Recently, however, insulin receptors have been detected throughout the central nervous system (CNS) of several species. Since important insights into the functional significance of brain insulin receptors might be provided by identification of the cell type(s) possessing these receptors, we have attempted to localise them morphologically using light and electron microscope autoradiography. We report here results indicating that blood vessels throughout the CNS of the rat bind plasma insulin rapidly and with considerable specificity.     

Stimulating illusory own-body perceptions

'Out-of-body' experiences (OBEs) are curious, usually brief sensations in which a person's consciousness seems to become detached from the body and take up a remote viewing position. Here we describe the repeated induction of this experience by focal electrical stimulation of the brain's right angular gyrus in a patient who was undergoing evaluation for epilepsy treatment. Stimulation at this site also elicited illusory transformations of the patient's arm and legs (complex somatosensory responses) and whole-body displacements (vestibular responses), indicating that out-of-body experiences may reflect a failure by the brain to integrate complex somatosensory and vestibular information.     

Localization of nitric oxide synthase indicating a neural role for nitric oxide.

Nitric oxide (NO), apparently identical to endothelium-derived relaxing factor in blood vessels, is also formed by cytotoxic macrophages, in adrenal gland and in brain tissue, where it mediates the stimulation by glutamate of cyclic GMP formation in the cerebellum. Stimulation of intestinal or anococcygeal nerves liberates NO, and the resultant muscle relaxation is blocked by arginine derivatives that inhibit NO synthesis. It is, however, unclear whether in brain or intestine, NO released following nerve stimulation is formed in neurons, glia, fibroblasts, muscle or blood cells, all of which occur in proximity to neurons and so could account for effects of nerve stimulation on cGMP and muscle tone. We have now localized NO synthase protein immunohistochemically in the rat using antisera to the purified enzyme. We demonstrate NO synthase in the brain to be exclusively associated with discrete neuronal populations. NO synthase is also concentrated in the neural innervation of the posterior pituitary, in autonomic nerve fibres in the retina, in cell bodies and nerve fibres in the myenteric plexus of the intestine, in adrenal medulla, and in vascular endothelial cells. These prominent neural localizations provide the first conclusive evidence for a strong association of NO with neurons.     

Bidirectional control of CNS capillary diameter by pericytes

Neural activity increases local blood flow in the central nervous system (CNS), which is the basis of BOLD (blood oxygen level dependent) and PET (positron emission tomography) functional imaging techniques. Blood flow is assumed to be regulated by precapillary arterioles, because capillaries lack smooth muscle. However, most (65%) noradrenergic innervation of CNS blood vessels terminates near capillaries rather than arterioles, and in muscle and brain a dilatory signal propagates from vessels near metabolically active cells to precapillary arterioles, suggesting that blood flow control is initiated in capillaries. Pericytes, which are apposed to CNS capillaries and contain contractile proteins, could initiate such signalling. Here we show that pericytes can control capillary diameter in whole retina and cerebellar slices. Electrical stimulation of retinal pericytes evoked a localized capillary constriction, which propagated at approximately 2 microm s(-1) to constrict distant pericytes. Superfused ATP in retina or noradrenaline in cerebellum resulted in constriction of capillaries by pericytes, and glutamate reversed the constriction produced by noradrenaline. Electrical stimulation or puffing GABA (gamma-amino butyric acid) receptor blockers in the inner retina also evoked pericyte constriction. In simulated ischaemia, some pericytes constricted capillaries. Pericytes are probably modulators of blood flow in response to changes in neural activity, which may contribute to functional imaging signals and to CNS vascular disease.     

T cells become licensed in the lung to enter the central nervous system

The blood–brain barrier (BBB) and the environment of the central nervous system (CNS) guard the nervous tissue from peripheral immune cells. In the autoimmune disease multiple sclerosis, myelin-reactive T-cell blasts are thought to transgress the BBB and create a pro-inflammatory environment in the CNS, thereby making possible a second autoimmune attack that starts from the leptomeningeal vessels and progresses into the parenchyma. Using a Lewis rat model of experimental autoimmune encephalomyelitis, we show here that contrary to the expectations of this concept, T-cell blasts do not efficiently enter the CNS and are not required to prepare the BBB for immune-cell recruitment. Instead, intravenously transferred T-cell blasts gain the capacity to enter the CNS after residing transiently within the lung tissues. Inside the lung tissues, they move along and within the airways to bronchus-associated lymphoid tissues and lung-draining mediastinal lymph nodes before they enter the blood circulation from where they reach the CNS. Effector T cells transferred directly into the airways showed a similar migratory pattern and retained their full pathogenicity. On their way the T cells fundamentally reprogrammed their gene-expression profile, characterized by downregulation of their activation program and upregulation of cellular locomotion molecules together with chemokine and adhesion receptors. The adhesion receptors include ninjurin 1, which participates in T-cell intravascular crawling on cerebral blood vessels. We detected that the lung constitutes a niche not only for activated T cells but also for resting myelin-reactive memory T cells. After local stimulation in the lung, these cells strongly proliferate and, after assuming migratory properties, enter the CNS and induce paralytic disease. The lung could therefore contribute to the activation of potentially autoaggressive T cells and their transition to a migratory mode as a prerequisite to entering their target tissues and inducing autoimmune disease.     

Morphological and electrophysiological evidence for regeneration of transected spinal cord fibers and restoration of motor functions in adult rats

The evoked potentials are regarded as an efficientindex to evaluate the functional status of a nervoussystem[1]. When stimulating the motor area of cerebralcortex with transcranial magnetic stimulation, elec-tronic signals can be obtained at the spinal co…     

电刺激对内皮细胞及血管组织的作用

电学环境是生物体所处的重要微环境之一,外加电刺激对内皮细胞和血管有重要作用.电刺激对细胞活性的影响已越来越引起人们的兴趣和重视,同时在生物科学中已得到了广泛的应用.文中就电刺激对内皮细胞粘附、增殖、迁移和分泌物产生的影响以及对血管收缩和舒张的影响及其机理作些介绍和分析.     

甘草中的活性物质在心脑血管疾病治疗中的应用

心脑血管疾病是心血管疾病和脑血管疾病的统称,其中,心血管疾病主要包括心脏病和心脏血管疾病;而脑血管疾病则指一类由脑部血管病变所引发的脑部机能障碍疾病。甘草是一味应用广泛的中药,甘草的主要生物活性成分包括三萜类化合物、黄酮类化合物及多糖类化合物等。近年来,甘草被广泛地应用于治疗脑缺血、记忆障碍、心肌缺血、心肌炎等心脑血管疾病,其临床应用具有广阔的前景。