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391.
目的 观察银杏叶制剂对左侧迷路切除后前庭内侧核 (medial vestibular nucleus,MVN )区突触素(synaptophysin)表达的影响 .方法 健康成年豚鼠 15只 ,随机分 3组 :正常对照组、迷路切除 (U L)组和 UL+金纳多(EGb)组 ,ip EGb,5 0 mg· kg- 1 · d- 1 ,共 30 d.左侧迷路切除后 ,不同存活时间行前庭内侧核突触素二步法免疫组化染色 .结果 一侧迷路切除 (unilateral labyrinthectomy,UL )后 10h,受损侧 MVN突触素免疫反应强度降低 ,2 0 d有所增加 (P<0 .0 5 ) ,90 d明显恢复至正常 (P>0 .0 5 ) .未损侧突触素免疫反应强度在不同时间段与正常对照无显著差别 .U L+金纳多 (EGb)组受损侧 ,术后 10 h及 2 0 d较同期 UL组 MVN突触素免疫反应强度高 (16 7.0± 2 .7,172 .5± 2 .0 vs 15 9.9±1.9,16 9.2± 3.1,P<0 .0 5 ) ,但术后 90 d与正常对照无显著差别 (P>0 .0 5 ) .结论 U L+EGb组突触密度恢复较 UL 组快 .前庭代偿及银杏叶制剂促进前庭代偿与前庭核区结构的调整有关 .银杏叶提取物对失支配侧前庭核的结构重塑具有易化作用 相似文献
392.
Julie Benedicte Brask Maj‐Lis Møller Talman Vera Timmermans Wielenga 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2014,122(7):593-598
Neuroendocrine carcinoma of the breast (NCB) is a fairly recent diagnostic entity added by WHO in 2003. Since then, studies have indicated that NCB potentially displays a worse prognosis than invasive ductal carcinoma. However, due to a lack of standard use of immunohistochemical staining for neuroendocrine markers and the fact that NCB may only show slight neuroendocrine morphology that can easily be overlooked, NCB is often underdiagnosed. Consequently, there is a need for fast and reliable detection method for NCB. Here, we take a first step toward finding an easy way of identifying NCB by investigating the usefulness of tissue microarray (TMA) analysis as a screening tool. We present our findings with regard to sensitivity and specificity compared with whole‐mount sections. The material consists of 240 cases of breast cancer divided into 20 TMA blocks that were all immunohistochemically stained for the neuroendocrine markers chromogranin A and synaptophysin. Cases positive in more than 50% of the tumor cells were accepted in accordance with WHO (2003) standards of NCB. Sensitivity and specificity for TMA sections vs whole‐mount sections were found to be 100% and 97.8%, respectively, suggesting that TMA analysis is a reliable method for NCB detection. 相似文献
393.
Evidence for subdivisions in the human suprachiasmatic nucleus 总被引:1,自引:0,他引:1
J K Mai O Kedziora L Teckhaus M V Sofroniew 《The Journal of comparative neurology》1991,305(3):508-525
The human suprachiasmatic nucleus was analysed by immunohistochemical demonstration of various substances in combination with 3-dimensional computerized reconstruction and video overlay facilities. In the human, the suprachiasmatic nucleus is not as compact as in the rodent. Its boundaries are not easily delineated using conventional stains, and it shows no obvious cytoarchitectonic structure. However, based on its chemoarchitecture, the human suprachiasmatic nucleus can be apportioned into five major subdivisions: Dorsal, comprising a crescent shaped mass of densely packed neurophysin/vasopressin-neurons as well as neurotensin-neurons, and also containing 3-fucosyl-N-acetyl-lactosamine (FAL)-positive neurons in its medial part. Central, occupying the core of the nucleus and consisting precisely of a region devoid of neurophysin/vasopressin neurons but demarcated by calbindin, synaptophysin, and a circumscribed cluster of vasoactive intestinal polypeptide-neurons and containing neurotensin neurons as well. Anteroventrally this division also contains some intermingled neurons positive for neurotensin, neuropeptide Y, somatostatin, and FAL. Ventral, extending from the anterior extreme of the preoptic recess caudolaterally to a field between the optic chiasm and the anteroventral margin of the supraoptic nucleus. This subdivision is specified by synaptophysin, calbindin, and substance P immunoreactivity and is almost free of glial fibrillary acidic protein. From its rostral portion, fibers immunoreactive for calbindin, vasoactive intestinal polypeptide, synaptophysin, and substance P protrude deeply into the optic chiasm. Medial, comprising a thin band between the subependymal zone and the dorsal subdivision, containing scattered somatostatin neurons. External, extending as a band around the dorsal and lateral borders of the nucleus, containing astrocytes expressing the FAL-epitope and scattered neurophysin/vasopressin and neurotensin neurons. These findings indicate that the human suprachiasmatic nucleus contains well-defined subdivisions with different, chemically specific, connections and provides a basis for comparing these subdivisions with the structure and function of subdivisions previously described for the suprachiasmatic nucleus in experimental animals. In addition, the findings strengthen the concept that the human suprachiasmatic nucleus generates and expresses circadian rhythms in a manner similar to that documented for the suprachiasmatic nucleus in experimental animals, and suggest that different subdivisions may subserve specific functional roles. 相似文献
394.
Peter Redecker 《Journal of pineal research》1993,15(4):199-207
Abstract: Previous studies have shown that pinealocytes of the gerbil pineal gland exhibit processes that form terminal swellings filled with abundant electron-lucent microvesicles. The membrane of these presumptive secretory microvesicles is known to contain synaptophysin, a major integral glycoprotein of neuronal synaptic vesicles. The present study was conducted to evaluate the microtopographical relationships between the vesicle-rich process swellings and intra-pineal nerve terminals. For this purpose, both nerve terminals and pinealocyte process endings were visualized immunohistochemically in the same semi-thin sections of plastic-embedded gerbil pineals, using antibodies directed against synaptophysin. This approach consistently revealed close spatial associations of punctate immunopositive nerve endings with intensely stained bulbous process terminals of pinealocytes in or near the perivascular spaces. The light-microscopic observations of intimate neuronal-pinealocytic relationships were corroborated at the electron-microscopic level. Perivascular varicosities with ultrastructural features characteristic of sympathetic nerve terminals were frequently juxtaposed to vesicle-filled process endings of pinealocytes. Analysis of serial thin sections showed that multiple point-to-point contacts are encountered between noradrenergic nerve terminals and pinealocytic process swellings. Our morphological findings imply that bulbous process terminals, at least in the gerbil pineal gland, are major targets for the neuronal control of the secretory activity of pinealocytes. 相似文献
395.
Chen Dan Tong Jian-Bin Wang Hui Zeng Le-Ping Zhou Jin Huang Ju-Fang Luo Xue-Gang 《ACTA HISTOCHEMICA ET CYTOCHEMICA》2008,41(6):173-178
In response to injury, synapse alteration may occur earlier than the changes in the cell body of neurons. Although retinal ganglion cell death and thinning of the inner part of retina were found after acute high intraocular pressure (HIOP), the structural and functional changes of synapses in the retina remain unknown. In the present study, we investigated the protein and mRNA expression of synaptophysin (SYN), an important molecule closely related to synaptic activities, synaptogenesis and synaptic plasticity. In addition, we also studied the ultrastructural changes of the retinal synapses. We found that (1) synaptophysin was upregulated transiently at both protein and mRNA level following HIOP; (2) broadened distribution of synaptophysin protein was present within the outer nuclear layer at the early stage following HIOP; (3) in the outer nuclear layer bouton-like vesicle-containing structures were observed by electron microscopy. This data suggested that, besides degeneration, synapses in rat retina may undergo regenerative events following HIOP. 相似文献
396.
神经生长因子对痴呆模型鼠海马突触素的影响 总被引:3,自引:0,他引:3
切断SD老年鼠(24月龄)左侧穹窿海马伞.造成隔海马胆碱能系统损害的痴呆模型. 用免疫组化和图像分析技术分析神经生长因子对痴呆鼠海马突触素的影响.实验证明损伤一个月后.损伤对照组损伤侧海马CAI区多形层、辐射层、腔隙分子层和齿状回分子层突触素含量分别是减少了28.17% 、32.15%、17.36%和35.22%:NGF治疗组、损伤侧海马CAI区多形层、辐射层、腔隙分子层和齿状回分子层突触素含量只减少了6.17%、5.52%、13.50%和3.81%.提示神经生长因子能够促使痴呆鼠海马内突触素含量的增多. 相似文献
397.
Summary The generalized form of von Winiwarter-Buerger's disease (WBD) occasionally involves the brain. However, pure cerebral forms of the disease were also described by Spatz and Lindenberg (Spatz-Lindenberg's disease, SLD). Both, the type I, which involves the large basal arteries, and the type II, which results in a sickle-shaped granular atrophy of the cerebral cortex, are often accompanied by (vascular) dementia, which Lindenberg and Spatz mainly attributed to the bilateral involvement of the second frontal gyrus by granular atrophy. Recently, synaptic deprivation of the cortical gray matter has been shown to occur in the dementia of Alzheimer type (DAT) and other neurodegenerative disorders. In DAT, the synaptic loss highly correlated with the degree of the mental impairment. We wanted to examine whether similar changes also occurred in dementia of vascular origin, for which SLD, although infrequent, is a typical example. In fact, we found that in three cases of typical SLD type II the synaptophysin immunoreactivity of the cortical neuropil in areas without overt infarcts or scar formation was as much reduced as in Alzheimer's disease. Although it must be taken into account that in the present cases the synapse loss might, at least in part, be due to secondary (Wallerian) degeneration as a result of the neuronal loss in the watershed regions of the arterial blood supply, it cannot be excluded that a decline of cortical synaptic contacts in areas without necroses or scars may occur as a primary event, contributing to the pathogenesis of the dementia. Final conclusions can only be expected from investigations into further cases of cerebro-vascular disorders with and without dementia.Presented at the 37th Annual Meeting of the German Society of Neuropathology and Neuroanatomy, e. V., Hamburg, September 23–26, 1992 相似文献
398.
Central Neurocytoma: 2 Case Reports and Review of the Literature 总被引:6,自引:0,他引:6
Dodero F Alliez JR Metellus P Hassan H Hassoun J Alliez B 《Acta neurochirurgica》2000,142(12):1417-1422
Summary Central neurocytoma is a rare benign tumor of the central nervous system occuring in young adults and typically located in
the ventricles. The tumor is composed of small round cells with neuronal differentiation and has a favourable prognosis. We
report two cases of giant central neurocytomas with a triventricular extension in two young women.
The first case concerned a 26 years old righthanded woman in whom an intraventricular mass was discovered, after a car accident
with head trauma. Skull radiography showed an enlargment of the sella turcica. A CT scan performed in order to examine the
pituitary gland revealed a voluminous and heterogenous intraventricular tumor with calcification.
The second case concerned a 26 years old righthanded woman, presenting with a 4 Glasgow Coma Scale Score preceded by an acute
onset of headache with projectile vomiting. A CT scan performed in emergency revealed a voluminous intraventricular mass with
significant hydrocephalus.
We review the different pathological and topographical patterns of previously published neurocytomas and discuss surgical
management, effectiveness of radiation therapy and biological behavior. 相似文献
399.
人胚胎小脑突触体素及NOS阳性细胞的观察 总被引:5,自引:0,他引:5
目的 研究人体胚胎时期小脑中突触体素及NOS阳性细胞的组织学变化。方法用免疫组织化学、组织化学技术,对4 ̄9个月胎儿小脑皮质突触体纱和NOS阳性细胞进行了观察。结果 突触体素在小脑不同层中的分布各不相同,外颗粒层4 ̄9个月均无阳性颗粒出现。4个月时除粒层各层免疫反应颗粒均很少,5个月时中间层的以较各层深,6个月时分子层的颗粒沿Bergmann纤维方向分布,7个月时分子层染色颗粒呈明显的网状分布。中 相似文献
400.
Fangyuan Cui Jiangying Zhai Weimeng Zou Xiling Wang Yihuai Zou Linggqun Zhu 《中国神经再生研究》2008,3(11):1212-1217
BACKGROUND: The change in expression of synaptophysin (Syp) and postsynaptic density-95 (PSD-95) alters after cerebral infarction, and the plasticity of synapses contributes greatly to nerve function recovery. Chinese medicinal substances may play an important role in the expression of Syp and PSD-95. OBJECTIVE: To observe the effect of Panaxtriol Saponins (PTS), an active component in Sanqi tongshu capsules, on the expression of Syp and PSD-95 after cerebral infarction at different time points in rats, so as to examine the cerebral function remodeling mechanism. DESIGN, TIME AND SETTING: A randomized and controlled observation which was performed in Dongzhimen Hospital, Beijing University of Traditional Chinese Medicine from January to March, 2007. MATERIALS: Twenty-six healthy male Sprague Dawley rats were used to establish middle cerebral artery occlusion based on the Longa method. Sanqi tongshu capsules (containing 100 mg PTS per tablet) were provided by the Chengdu Huashen Group and nimodipine tablets (30 mg) by Tianjin Zhongyang Pharmaceutical Co., Ltd. METHODS: Twenty-six rats were randomly divided into an operation group (n = 21 ) and a control group (n = 5). The operation group underwent the EZ Longa procedure to make the middle cerebral artery occlusion model. After surgery rats were randomly divided into a model group, a PTS group and a nimodipine group, with seven rats in each group. Rats were intragastrically administrated with saline (2 mL/d) in the model group, with Sanqi tongshu capsule (5.4 mg/100 g/d) in the PTS group, and with nimodipine (1.73 mg/100 g/d) in the nimodipine group. Rats in the control group did not undergo model establishment and drug administration. MAIN OUTCOME MEASURES: The expressions of Syp and PSD-95 were measured by immunohistochemical and image analysis at days 3, 7 and 28 after the operation. RESULTS: The expression of Syp and PSD-95 in the operation group was significantly lower than in the control group at days 3, 7 相似文献