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61.
目的 研究双侧丘脑底核(STN)脑深部电刺激术(DBS)治疗原发性肌张力障碍的长期疗效:方法 比较15例行舣侧STN—DBS治疗的原发性肌张力障碍患者,手术前后的Burke—Fahn—Marsden肌张力障碍评分改善程度及长期改善效果。结果 15例原发性肌张力障碍患者中12例在开启刺激器后症状即刻得到部分缓解,以不自主运动、异常姿势及躯体的扭转改善为主,其中9例在刺激1—3d后、3例刺激1,周后改善75%以上,6个月后平均改善92%;1例在2个月后开始改善,6个月后改善90%以上;2例在1个月开始出现轻微改善,6个月后改善了76%:15例患者的长期随访结果显示其疗效稳定,经过1—3次程控后不需经常调整刺激参数:所有患者未出现手术相关并发症及永久性副作用。结论 双侧丘脑底核脑深部电刺激术对原发性肌张力障碍有显著的治疗效果,且疗效持久、稳定,无并发症及永久性副作用。比较GPi—DBS而言,STN—DBS起效快、最件刺激化点及参数易于确定、刺激参数水平低、长期疗效稳定,可能是原发性肌张力障碍DBS治疗的理想靶点。 相似文献
62.
R P Vertes 《The Journal of comparative neurology》1992,326(4):595-622
The projections of the supramammillary nucleus (SUM) were examined in the rat by the anterograde anatomical tracer Phaseolus vulgaris leucoagglutinin (PHA-L). The majority of labeled fibers from SUM ascended through the forebrain within the medial forebrain bundle. SUM fibers were found to terminate heavily in the hippocampal formation, specifically within the granule cell layer and immediately adjoining molecular layer of the dentate gyrus. In addition, SUM fibers were shown to distribute densely to several structures with strong connections with the hippocampus, namely, the nucleus reunions of the thalamus, the medial and lateral septum, the entorhinal cortex, and the endopiriform nucleus. SUM fibers were also shown to project significantly to several additional subcortical and cortical sites. The subcortical sites were the dorsal raphe nucleus, the midbrain central gray, the fields of Forel/zona incerta, the dorsomedial hypothalamic area, midline/intralaminar nuclei of the thalamus (posterior paraventricular, rhomboid, central medial, intermediodorsal, and mediodorsal), the medial and lateral preoptic areas, the bed nucleus of the stria terminalis, the substantia innominata, the vertical limb of the diagonal band nucleus, and the claustrum. The cortical sites were the occipital, temporal, parietal, and frontal cortices. Some notable differences were observed in projections from the lateral as compared to the medial SUM. For example, fibers originating from the lateral SUM distributed heavily to the hippocampal formation and parts of the cortex, whereas those from the medial SUM projected sparsely to these two regions. The SUM projections to the hippocampal formation and associated structures may serve as the substrate for a SUM involvement in the generation of the theta rhythm of the hippocampus and the gating of information flow through the hippocampal formation. 相似文献
63.
Axotomy of the rat facial nerve leads to increased CR3 complement receptor expression by activated microglial cells 总被引:5,自引:0,他引:5
Axotomy of the rat facial nerve leads to mitotic divisions of microglial cells without developing into phagocytes. In order to study the functional characteristics of those activated, i.e., proliferating but nonphagocytic, microglia we investigated the expression of monocyte/macrophage antigens by these cells. Our results show that activated microglia lack monocyte/macrophage antigens recognized by the monoclonal antibodies Ox-41, ED1, ED2, and Ki-M2R but express high levels of CR3 complement receptors in situ. 相似文献
64.
大肠癌旁粘膜细胞的PCNA和AgNORs表达观察 总被引:2,自引:0,他引:2
用增殖细胞核抗原(PCNA)和核仁组成区嗜银蛋白(AgNORs)对35例大肠癌旁粘膜进行细胞增殖表达与观察。结果表明:癌旁粘膜的PCNA标记指数增多,标记增强,排列紊乱。AgNORs在癌旁粘膜中,颗粒增多、增大,形态多样,0 ̄1cm和2 ̄3cm组的标记指数与4 ̄5cm组的标记指数相比较,有显著或非常显著差异(P〈0.05或P〈0.01)。在DukeA、B期中,细胞标记指数增高增强,与癌的发生和患者 相似文献
65.
Summary A series of in vivo experiments were undertaken, relating functional (motor activity, body temperature), dopamine (DA) receptor binding and neurochemical (catecholamine synthesis and utilization, DA release) aspects of the pharmacology of SCH 23390 in the rat.The compound inhibited the locomotor hyperactivity, but not the hypothermia, induced by the potent DA stimulant DP-5,6-ADTN. Interstingly, SCH 23390 simultaneously failed to displace DP-5,6-ADTN from its binding sites in the rat striatum—used as a direct in vivo biochemical index of DA (D-2) receptor interaction. The spontaneous locomotion in non-pretreated rats was likewise inhibited by SCH 23390. The locomotor-suppressive action, but not the DP-5,6-ADTN-displacing capcity of the D-2 blocker haloperidol was significantly enhanced by SCH 23390, suggesting that motility can be suppressed by either enhanced D-1 or D-2 (postsynaptic) receptor blockade, but also that the D-1 and D-2 sites involved may be physically distinct.SCH 23390 only slightly altered in vivo neurochemical of DA synthesis, release and nerve-impulse flow, indicating that, while similar in suppressing dopaminergic behaviour, the D-1 antagonist is less effective than traditional neuroleptics as an activator of DA neuronal feedback mechanisms. The weak increases of DA synthesis and release nonetheless obtained were equal in magnitude (30–40%) in the limbic vs. striatal brain areas; also in this respect, SCH 23390 thus differs from classical neuroleptics, which generally display more marked effects in the striatum than in limbic tissue.No major changes in the in vivo indices of NA synthesis and utilization (or in 5-HT synthesis) were found after SCH 23390 administration, by and large supporting the DA receptor specificity of the compound.In summary, the studies demonstrated that SCH 23390 can offset and accentuate, respectively, behavioural consequences of D-2 receptor stimulation and blockade. Importantly, at the same time no direct interaction at the level of D-2 DA receptor sites in the striatum was detected. Only slight, D-2 antagonist-like, changes in neurochemical indices of dopaminergic activity were observed after D-1 receptor blockade by means of SCH 23390. With regard to DA agonist hypothermia, SCH 23390 was without effect per se, but (at a high dose) attenuated the action of the D-2 antagonist haloperidol. The observations may indicate that the complex interactions between central D-1 and D-2 receptor-controlled mechanisms that influence behaviour, neurochemistry, and possibly autonomic nervous expression, are not identical. 相似文献
66.
Recent evidence suggests that a variety of hypothalamic neuropeptides may mediate interneuronal communication to coordinate diverse neuroendocrine and behavioral functions. In this work, we describe the effects of neuropeptide Y (NPY) on feeding and sexual behaviors. We observed that central administration of bolus NPY stimulated a robust, dose-related feeding response in satiated male and female rats. Continuous NPY receptor activation also evoked dose-related, intermittent feeding in a manner normally observed during nocturnal feeding. It appears that the paraventricular nucleus in the hypothalamus may be the primary site of NPY action because the anticipated reciprocal changes in NPY concentrations, in response to food deprivation followed by ad libitum food intake, occurred only in this site. Additional findings revealed that NPY-induced feeding may follow either substantial reduction or complete restraint of an inhibitory influence on feeding mediated by alpha 2-adrenoreceptor systems in satiated rats. Further, NPY was found to suppress male and female sexual behaviors. The suppressive effects on sexual behavior were apparent prior to or at the time of the onset of feeding after NPY administration. These observations may provide a neurochemical basis for clinical and animal studies on disorders of feeding associated with diminished reproductive functions. 相似文献
67.
Current knowledge on the anatomy of area 3a of the cat mainly derives from the cyto- and myeloarchitectonic study of Hassler and Muhs-Clement (J Hirnforsch 6:377, 1964). Previous investigations in the cat had failed to identify a cortical region comparable to monkey's area 3a. In the present study, Nissl, myelin, acetylcholinesterase, and cytochrome oxidase staining techniques were applied to coronal and sagittal serial sections of the cat brain. Area 3a appears as a slender band of cortex between areas 4 and 3b, and in Nissl-stained sections it is mainly characterized by an attenuated granular layer IV, overlying a thin layer V with pyramidal cells of various sizes, including a few large ones. These cytoarchitectonic features are sufficient to differentiate area 3a from neighboring areas, although the borders between them are not sharp in many cases. After the Nissl staining, the acetylcholinesterase staining proved to be the most helpful in defining the structure and borders of area 3a. Acetylcholinesterase staining was dense in layer I (in contrast with a lighter staining of outer layer I in area 4), and light in layers II and IIIa, changing to moderate in IIIc and IV (a pattern which is accentuated in area 3b). Myelin and cytochrome oxidase techniques also yielded differential staining patterns of area 3a and neighboring areas 4 and 3b, although the borders were not easily drawn with these techniques. Whereas our cyto- and myeloarchitectonic findings were comparable to those of Hassler and Muhs-Clement ('64) and applied well to area 3a in the convexity of the hemisphere, we found that most of the area 3a described by these authors in the medial face of the hemisphere had a number of distinguishing architectonic (as well as connectional and physiological) features which enabled us to define it as a separate area (7m). The techniques we used to delineate area 3a are compatible with most current procedures of histo- and immunohistochemical staining of the brain, and may also provide valuable supporting data for electrophysiological studies. 相似文献
68.
实验在15只家兔上进行。以玻璃微电极记录尾核头部(DHCN)痛相关单位,刺激扣带回,观察痛相关单位电活动的变化。在70只DHCN痛相关单位中,有44个对刺激扣带回表现兴奋反应(62.9%),17个呈抑制反应(24.3%),9个变化不明显(12.8%)。进一步观察了52只痛相关单位,在刺激扣带回后再施伤害刺激,43个原痛兴奋单位中15个转为抑制(34.9%),16个进一步兴奋(37.2%)12个无变化(27.9%);原9个痛抑制单位,8个转为兴奋,1个变化不明显。提示,扣带回可通过其下行活动,调制伤害性冲动在尾核水平上的传递。 相似文献
69.
70.
The present investigation introduces an in vitro model to study macrophage properties during demyelination. Rat dorsal root ganglia (DRG) were cultured for obtaining myelinated peripheral nerve fibers. These cultures were exposed to non-resident macrophages. In untreated control cultures, there was no indication of myelin removal by the added macrophages. DRG were exposed to enzymatically generated oxygen radicals using the xanthin/xanthin oxidase or the glucose/glucose oxidase system. Assessment of Schwann cell viability and ultrastructural morphology revealed different patterns of cell cytotoxicity and morphological changes in different experiments. High concentrations caused complete tissue necrosis of the DRG, while low concentrations did not affect either cell viability or ultrastructural morphology. Under intermediate experimental conditions, oxygen radicals caused non-lethal Schwann cell damage leading to Schwann cell retraction and myelin sheath rejection. Myelin lamellae were disrupted and decompacted. These changes were followed by a selective macrophage attack on myelin sheats, resulting in demyelination. Axons, Schwann cells and sensory ganglion cells survived this attack. The specificity of the oxygen radical effects was tested in experiments using the oxygen radical scavengers catalase and superoxide dismutase. Catalase prevented the described effects on cell morphology and subsequently blocked demyelination by non-resident macrophages.Supported by a grant from the Deutsche Forschungsgemeinschaft (DFG) (Br 1274/1-1) 相似文献