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91.
Nerve growth factor (NGF) is crucial for the development of sympathetic and small-diameter sensory neurons and for maintenance of their mature phenotype. Its role in generating neuronal pathophysiology is less well understood. After spinal cord injury, central processes of primary afferent fibers sprout into the dorsal horn, contributing to the development of autonomic dysfunctions and pain. NGF may promote these states as it stimulates sprouting of small-diameter afferent fibers and its concentration in the spinal cord increases after cord injury. The cells responsible for this increase must be identified to develop a strategy to prevent the afferent sprouting. Using immunocytochemistry, we identified cells containing NGF in spinal cord sections from intact rats and from rats 1 and 2 weeks after high thoracic cord transection. In intact rats, this neurotrophin was present in a few ramified microglia and in putative Schwann cells in the dorsal root. Within and close to the lesion of cord-injured rats, NGF was in many activated, ramified microglia, in a subset of astrocytes, and in small, round cells that were neither glia nor macrophages. NGF-immunoreactive putative Schwann cells were prevalent throughout the thoracolumbar cord in the dorsal roots and the dorsal root entry zones. Oligodendrocytes were never immunoreactive for this protein. Therapeutic strategies targeting spinal cord cells that produce NGF may prevent primary afferent sprouting and resulting clinical disorders after cord injury.  相似文献   
92.
A Cell Culture Model for Androgen Effects in Motor Neurons   总被引:8,自引:2,他引:6  
Abstract: Androgens are known to alter the morphology, survival, and axonal regeneration of lower motor neurons in vivo. To understand better the molecular mechanisms of androgen action in neurons, we created a model system by stably expressing the human androgen receptor (AR) in motor neuron hybrid cells. Motor neuron hybrid cells express markers consistent with anterior horn cells and can be differentiated into a neuronal phenotype. When differentiated in the presence of androgen, AR-expressing cells, but not control cells, exhibit a dose-dependent change in morphology: androgen-treated cells develop larger cell bodies and broader neuritic processes while continuing to express neuronal markers. In addition, androgen promotes the survival of AR-expressing cells, but not control cells, under low-serum conditions. Our results demonstrate a direct trophic effect of androgens on lower motor neurons, mediated through the AR expressed in this population of neurons.  相似文献   
93.
94.
为研究代谢型谷氨酸受体各亚型在猫脊髓内的定位分布特征,本实验采用免疫组织化学方法调查了代谢型谷氨酸受体五种亚型(mGluR1,mGluR2,mGluR3,mGlur5及mGluR7)在猫脊髓(颈2、颈6、胸5、腰6、骶1-2)内的分布状况。结果如下:(1)在背角深层(Ⅲ-Ⅳ层)和腹角内分布有大量中小型(<30μm)mGluR1样免疫反应阳性神经元,背角浅层(Ⅰ、Ⅱ层)为阴性;(2)mGluR2/3样免疫反应阳性产物仅见于背角Ⅱ层内侧部,其它部位为阴性;(3)致密的mGluR5样免疫反应阳性产物主要分布于猫脊髓背角Ⅱ层的神经毯内,背角Ⅰ层及深层呈中等密度染色;(4)致密的mGluR7样免疫反应阳性产物分布于背角Ⅱ层的神经毯内,背角Ⅰ层及深层(Ⅲ-Ⅳ层)呈中等密度染色。此外,腹角运动神经元和骶髓副交感核内的神经元亦呈现mGluR7样免疫反应阳性。单侧切断背根,发现术侧背角浅层内mGluR7样免疫反应阳性产物密度略有降低,而mGluR5样免疫反应阳性产物密度与对侧基本相同。本研究结果显示代谢型谷氨酸受体五种亚型在所调查的猫脊髓各节段内(颈2、颈6、胸5、腰6、骶1-2)的分布存在差异,提示它们在介导谷氨酸传递的信  相似文献   
95.
本研究采用SDS凝胶电泳方法从人脊神经前根中分离出人脊髓前角运动神经元特有的蛋白—190KD。将该蛋白作为抗原,免疫BALB/c小鼠,经杂交瘤技术,获得了抗190KD蛋白的单克隆抗体。免疫细胞化学检测表明,190KD单抗与脊髓灰质前角神经元、前根及肌支发生阳性反应。实验结果提示,190KD蛋白分布在脊髓运动神经元胞体及脊神经的前根和肌支纤维中。  相似文献   
96.
Background  The potential of Atipamezole (ATI) to reverse Ketamine/Xylazine (KET/XYL) anesthesia in the Olive baboon ( Papio anubis ) was studied.
Methods  Anesthesia was induced with 10 mg/kg KET and 0.5 mg/kg XYL intramuscularly. Mean arousal time (MAT), heart rate (HR), systolic arterial blood pressure (SAP), rectal temperature, respiratory rate (RR), and hemoglobin oxygen saturation (SpO2) were monitored. Baboons were treated with: KET/XYL only, KET/XYL followed by 100 μg/kg ATI or by 200 μg/kg ATI administered 25 minutes after KET/XYL.
Results  Atipamezole rapidly reversed depressed HR and SAP (10 ± 5.2 minutes), RR (5 ± 2 minutes) and SpO2 (3 ± 6 minutes) and significantly decreased MAT (13 ± 2.2 minutes) vs. KET/XYL alone (35 ± 5 minutes). Emesis was absent and salivation was observed after administration of 200 μg/kg ATI only.
Conclusions  Atipamezole at 100 μg/kg is sufficient for rapid and smooth reversal of KET/XYL anesthesia in the Olive baboon with minimal side effects.  相似文献   
97.
目的:探讨硬膜外复合全麻对老年高血压患者腹部手术后并发生的影响。方法:收集2013 年6 月-2015 年6 月在两家医院 接受腹部手术的老年高血压患者100 例,根据麻醉方法不同分为研究组和对照组。研究组患者给予硬膜外复合麻醉,对照组给予 全凭静脉麻醉。观察并比较两组患者的麻醉时间、药物用量以及术后并发症的发生率。结果:两组麻醉时间比较,差异无统计学意 义(P>0.05);研究组麻醉药物用量低于对照组,差异具有统计学意义(P<0.05);两组患者手术时间比较,差异无统计学意义(P>0. 05);研究组患者术后苏醒时间、拔管时间以及住院时间均短于对照组,差异具有统计学意义(P<0.05);研究组术后并发症的发生 率低于对照组,差异具有统计学意义(P<0.05)。结论:硬膜外复合全麻用于老年高血压患者腹部手术能够减少麻醉药物用量,降低 术后并发症的发生率,安全性较高。  相似文献   
98.
目的:探讨分析老年非心脏手术患者全身麻醉术后认知功能障碍(POCD)的影响因素。方法:选择我院80 例老年行非心脏手 术患者,所有患者均给予全身麻醉手术,于术前及术后1、3 d 分别使用简易智能状态检查法(MMSE)评估患者认知功能,同时记 录行不同手术种类患者POCD 发生率并分析其年龄、麻醉时间、术中出血量、并发症情况及受教育程度等指标与POCD发生的相 关性。结果:80 例患者POCD发生率为30.0%,且不同种类手术中的发生率比较差异无统计学意义(P>0.05);POCD 组术后1d MMSE 评分为较术前分明显下降,比较差异具有统计学意义(P<0.05);POCD组术后3 d及非POCD 组术后1、3 d MMSE 评分与 术前比较差异无统计学意义(P>0.05);Logistic 回归分析显示,患者年龄、文化程度、麻醉持续时间≥ 3 h、术中出血量≥ 350 mL及 合并高血压与POCD的发生具有显著相关性(P<0.05)。结论:行全麻手术患者术后POCD 发病率较高,且患者高龄、文化程度 低、高血压合并症及麻醉持续时间长等是引起POCD发生的重要影响因素。  相似文献   
99.
Monitoring depth of anesthesia (DOA) via vital signs is a major ongoing challenge for anesthetists. A number of electroencephalogram (EEG)-based monitors such as the Bispectral (BIS) index have been proposed. However, anesthesia is related to central and autonomic nervous system functions whereas the EEG signal originates only from the central nervous system. This paper proposes an automated DOA detection system which consists of three steps. Initially, we introduce multiscale modified permutation entropy index which is robust in the characterization of the burst suppression pattern and combine multiscale information. This index quantifies the amount of complexity in EEG data and is computationally efficient, conceptually simple and artifact resistant. Then, autonomic nervous system activity is quantified with heart rate and mean arterial pressure which are easily acquired using routine monitoring machine. Finally, the extracted features are used as input to a linear discriminate analyzer (LDA). The method is validated with data obtained from 25 patients during the cardiac surgery requiring cardiopulmonary bypass. The experimental results indicate that an overall accuracy of 89.4 % can be obtained using combination of EEG measure and hemodynamic variables, together with LDA to classify the vital sign into awake, light, surgical and deep anesthetised states. The results demonstrate that the proposed method can estimate DOA more effectively than the commercial BIS index with a stronger artifact-resistance.  相似文献   
100.
General anesthetics achieve behavioral unresponsiveness via a mechanism that is incompletely understood. The study of genetic model systems such as the fruit fly Drosophila melanogaster is crucial to advancing our understanding of how anesthetic drugs render animals unresponsive. Previous studies have shown that wild-type control strains differ significantly in their sensitivity to general anesthetics, which potentially introduces confounding factors for comparing genetic mutations placed on these wild-type backgrounds. Here, we examined a variety of behavioral and electrophysiological endpoints in Drosophila, in both adult and larval animals. We characterized these endpoints in 3 commonly used fly strains: wild-type Canton Special (CS), and 2 commonly used white-eyed strains, isoCJ1 and w1118. We found that CS and isoCJ1 show remarkably similar sensitivity to isoflurane across a variety of behavioral and electrophysiological endpoints. In contrast, w1118 is resistant to isoflurane compared to the other 2 strains at both the adult and larval stages. This resistance is however not reflected at the level of neurotransmitter release at the larval neuromuscular junction (NMJ). This suggests that the w1118 strain harbors another mutation that produces isoflurane resistance, by acting on an arousal pathway that is most likely preserved between larval and adult brains. This mutation probably also affects sleep, as marked differences between isoCJ1 and w1118 have also recently been found for behavioral responsiveness and sleep intensity measures.  相似文献   
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