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41.
Role of group II and group III metabotropic glutamate receptors in spinal cord injury. 总被引:4,自引:0,他引:4
Spinal cord injury (SCI) produces an increase in extracellular excitatory amino acid (EAA) concentrations that results in glutamate receptor-mediated excitotoxic events. An important class of these receptors is the metabotropic glutamate receptors (mGluRs). mGluRs can activate a number of intracellular pathways that increase neuronal excitability and modulate neurotransmission. Group I mGluRs are known to modulate EAA release and the development of chronic central pain (CCP) following SCI; however, the role of group II and III mGluRs remains unclear. To begin evaluating group II and III mGluRs in SCI, we administered the specific agonists for group II, APDC, or group III, L-AP4, by interspinal injection immediately following SCI. Contusion injury was produced at spinal segment T10 with a New York University impactor (12.5-mm drop, 10-g rod 2 mm in diameter) in 30 adult male Sprague-Dawley rats (175-200 g). Evoked and spontaneous behavioral measures of CCP, locomotor recovery, changes in mGluR expression, and amount of spared tissue were examined. Neither APDC nor L-AP4 affected locomotor recovery or the development of thermal hyperalgesia; however, L-AP4 and APDC attenuated changes in mechanical thresholds and changes in exploratory behavior indicative of CCP. APDC- and L-AP4-treated groups had higher expression levels of mGluR2/3 at the epicenter of injury on post contusion day 28; however, there was no difference in the amount of spared tissue between treatment groups. These results demonstrate that treatment with agonists to group II and III mGluRs following SCI affects mechanical responses, exploratory behavior, and mGluR2/3 expression without affecting the amount of tissue spared, suggesting that the level of mGluR expression after SCI may modulate nociceptive responses. 相似文献
42.
参附注射液对肠缺血-再灌注大鼠肿瘤坏死因子α的影响 总被引:5,自引:0,他引:5
目的观察肿瘤坏死因子α(TNF-α)在大鼠肠缺血-再灌注损伤过程中的作用及参附注射液对TNF-α的影响,探讨参附注射液防治肠缺血-再灌注损伤机制。方法 SD大鼠随机分为肠缺血-再灌注组(IR组)、参附注射液预处理组(SF组)和假手术组(C组)。采用阻断肠系膜上动脉(SMA)的方法制造肠缺血-再灌注模型。分别测定各组动物血浆、肠组织TNF-α含量及血液动力学变化;光镜观察肠粘膜损伤情况。结果IR组再灌注后MAP下降,与C组和SF组比有显著性差异(P<0.01);SF组肠粘膜损伤程度减轻,与IR组比有显著性差异(P<0.01);SF组血浆及肠组织TNF-α水平降低,与IR组比有显著性差异(P<0.01)。结论参附注射液可明显防治大鼠肠缺血-再灌注导致的肠粘膜损伤,这种作用可能是通过抑制TNF-α的释放实现的。 相似文献
43.
金尔伦治疗急性颅脑损伤的剂量效应研究 总被引:2,自引:1,他引:1
目的探讨金尔伦(盐酸纳洛酮)在治疗大鼠液压脑损伤后神经功能恢复和病理损害程度的剂量效应.方法将104只SD大鼠随机分为4组,伤后早期分别腹腔注射0.03 mg/Kg(小剂量组)、0.3 mg/Kg(中剂量组)、3 mg/Kg(大剂量组)金尔伦和等量生理盐水(对照组),连续7 d.结果中、大剂量组动物伤后脑神经功能恢复、脑水肿减轻程度及光、电镜检查显著优于对照组及小剂量组.结论伤后早期使用中剂量和大剂量金尔伦(盐酸纳洛酮)对大鼠液压颅脑损伤有明显的治疗效果. 相似文献
44.
A. Compston 《Acta neurologica Scandinavica》2006,113(S183):41-47
Contemporary licensed treatments for multiple sclerosis fail to provide a solution for the disease because their effects are limited to a modest reduction in the frequency of new episodes. They do not reduce disability or materially influence the progressive phase of the disease. A contemporary strategy for management requires a more detailed analysis of the separate contributions to the clinical features and overall course made by inflammation, axonal injury, compensatory mechanisms, and remyelination. From this formulation emerges the need either for early and fully effective suppression of the inflammatory response, limiting the damage to all components of the axon-glial unit; or the development of strategies for axonal and myelin repair that solve the issues of controlled differentiation, delivery and timing of these cell and growth factor-based interventions. 相似文献
45.
贺光照 《重庆医科大学学报》1992,(2)
本文根据34例电击伤临床资料,分析早期处理与病人全身情况、局部损伤愈合以及并发症的关系.并讨论间生态组织的处理原则.结果表明:伤后1天内与伤后3天以上就诊的病人比较,前者全身情况良好,创面感染率低,局部损伤用皮瓣或(和)皮片覆盖效果满意,并发症及截肢率均较低 相似文献
46.
乳癌根治术是治疗乳腺癌的主要手段,但并发臂丛神经损伤的报道却很少,总结从1989年10月~1991年2月华山医院诊治的9例,3例门诊治疗,6例住院治疗。其中5例行神经松解后,皮瓣或肌皮瓣转移覆盖神经瘢痕区。随访到8例,疼痛改善3例,感觉和运动改善2例,疗效不理想,认为寻找预防措施是减少乳癌根治术后臂丛损伤的根本办法。 相似文献
47.
48.
Summary Thirty-four rats were killed by transcardial perfusion fixation 1 min after a contusing concussive head injury, and 17 rats 1 day later. From the results obtained with a new silver method demonstrating traumatically damaged neuronal somata, dendrites and axons the following conclusions were drawn: (1) outside the contused territories all features of traumatically induced neuronal argyrophilia are similar to those found in non-contusing concussive head injury, as reported in an accompanying paper; (2) within contused territories the neuronal argyrophilia is abolished by some substance released either from damaged blood vessels or from damaged parenchymal cells, while the neuronal damage otherwise underlying the induction of argyrophilia is present; (3) different phenotypes of neurons are vulnerable to different values of the parameters of the intracranial pressure wave generated by the trauma; (4) some of the neurons may recover from the traumatically induced argyrophilic damage; (5) traumatically induced inundation of neurons with extracellular tracers, as reported by other authors, and somato-dendritic argyrophilia may be different manifestations of one and the same phenomenon; and (6) diffuse primary traumatic axonal injury in human neuropathology may be closely correlated to axonal argyrophilia. 相似文献
49.
H.G. Peltenburg B.H.R. Wolffenbuttel M.H. Booster P.P.C.A. Menheere K.M.L. Leunissen G. Kootstra J.P. van Hooff 《Transplant international》1992,5(Z1):S270-S271
It is unknown to what extent preservation and/or reperfusion may damage islet cells in pancreas allografts. In this study, the release of insulin after reperfusion was used as a marker of injury to the islet cell and compared with the best insulin secretory response (ISR) after glucagon stimulation over a period of 100 days after pancreas transplantation. 相似文献
50.
改良前肩峰成形术治疗肩部撞击症23例的临床报告 总被引:1,自引:1,他引:0
目的分析、总结、改良前肩峰成形术治疗肩部撞击症的临床疗效。方法本组23例肩部撞击症患者为研究组,全部采用改良前肩峰成形术。另23例为对照组,采用传统手术方法。结果两组治疗结果经统计学处理具有显著意义(P<0.05),研究组23例肩部撞击症患者全部治愈。结论改良前肩峰成形术治疗肩部撞击症,使肩峰下间隙充分减压,以消除撞击因素,维持肩关节原有的解剖结构,保留第二肩关节的完整性,手术创伤小,早期功能锻练,肩关节功能恢复满意,明显优于对照组。 相似文献