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71.
72.
Neuroactive steroids: State of the art and new perspectives 总被引:1,自引:0,他引:1
Melcangi RC Garcia-Segura LM Mensah-Nyagan AG 《Cellular and molecular life sciences : CMLS》2008,65(5):777-797
Neuroactive steroids include synthetic steroidal compounds and endogenous steroids, produced by endocrine glands (hormonal
steroids) or the nervous tissue (neurosteroids), which regulate neural functions. These steroids bind to nuclear receptors
or act through the activation of membrane-associated signaling pathways to modulate various important processes including
the development of the nervous system, neural plasticity and the adaptive responses of neurons and glial cells under pathological
conditions. Reviewed and updated in the present paper are the pleiotropic and protective abilities of neuroactive steroids.
The fundamental evidence and knowledge gained constitute a profound background that offers interesting possibilities for developing
effective strategies against several disorders of the nervous system.
Received 3 September 2007; received after revision 24 October 2007; accepted 29 October 2007 相似文献
73.
紊流性泥石流对渡槽的作用力分析 总被引:1,自引:0,他引:1
针对紊流性泥石流特点,对渡槽的受力情况进行了比较深入的分析。在垂直于渡槽边壁方向,泥石流体对渡槽的总作用力由紊流性泥石流体对渡槽结构的全压力和紊流性泥石流体中砂石垂直于边壁冲击力组成;在平行于渡槽边壁方向,泥石流体对渡槽的作用力由公式(10)及(11)来表示。最后对这些公式的应用和一些极限情况进行了讨论,为渡槽的设计提供了理论和实践上的依据。 相似文献
74.
Neural stem cell transplantation in the repair of spinal cord injury 总被引:17,自引:0,他引:17
Neural stem cells are a pronising candidate for neural transplantation aimed at neural cell replacement and repair of the damaged host central nervous system (CNS). Recent studies using neural stem cells have shown that implanted neural stem cells can effectively incorporate into the damaged CNS and differentiate into neurons, astrocytes, and oligodendrocytes. The recent explosion in the field of neural stem cell research has provided insight into the inductive factors influencing neural stem cell differentiation and may yield potential therapies for several neurological disorders, including spinal cord injury. In this review, we summarize recent studies involving neural stem cell biology in both rodents and humans. We also discuss unique advantages and possible mechanisms of using neural stem cell trans plantation in the repair of spinal cord injury. 相似文献
75.
目的:研究根管治疗过程中3种暂封材料的临床封闭效果。方法:选取300颗患牙,其中单面洞150颗,复面洞150颗,随机分别采用Ceivtron暂封膏、氧化锌丁香油水门汀和牙胶条封闭1周后观察其封闭性能。选取450颗患牙(全部为单面洞),分成9组,分别采用Ceivtron暂封膏、氧化锌丁香油水门汀和牙胶条封闭3 d,1周,2周后观察其封闭性能。结果:Ceivtron暂封膏组和氧化锌丁香油水门汀组封闭性能相当,均优于牙胶条组。但氧化锌丁香油水门汀的特殊气味不易被患者接受。结论:Ceivtron暂封材料是临床综合效果较好的暂封材料。 相似文献
76.
目的:观察在腰-硬联合麻醉剖宫产术中使用羟乙基淀粉预扩容的临床效果。方法:选择腰-硬联合麻醉(CSEA)下择期剖宫产手术60例,随机分为2组,HES组(n=30)给6%羟乙基淀粉130/0.4氯化钠注射液500 mL进行预扩容,LR组(n=30)给予乳酸钠林格注射液500 mL进行预扩容。观察两组患者麻醉后低血压、恶心呕吐、麻黄碱的用量及术中液体用量的情况。结果:HES组麻醉后低血压的发生率、麻黄碱的用量及术中液体用量均低于LR组,差异有统计学意义(P<0.05)。结论:羟乙基淀粉预扩容能更好维持剖宫产术中血流动力学的稳定,保障产妇和胎儿的安全。 相似文献
77.
The relationship between the automatic control method and the stability of the open canal is studied by means of numerical simulation of unsteady flow in an open canal under different methods of control. It is found the Proportional-Proportional plus Reset (P+PR) control is more reliable than the Linear Quadratic Regulator (LQR) control. Moreover, for the P+PR control, the hydraulic response of the constant volume method of operation is better than that of the constant downstream depth method in the type of centrally controlled canal. Therefore, an appropriate flow change rate should be chosen instead of shortening the pool length to reach an acceptable drawdown rate. For the canal with a bottom width of 40 m, side slope of 3, Manning n of 0.015, bottom slope of 0.000 04, and design flow of 600 m3/s, the pool length of more than 30 km can provide acceptable drawdown rates of 0.2 m/h when a proper flow change rate is chosen. 相似文献
78.
杨军 《重庆工商大学学报(自然科学版)》1996,(2)
通过对24倒后鼻道出血的临床治疗,笔者认为止血方法可首选翼腭管注射法。此法具有快捷、无痛苦、疗效好等优点。即使注射法失败再采用后鼻道填塞法,也不失抢救时机。 相似文献
79.
Sensory information arising from somatic and visceral area is thought to be respectively transmitted to the brain by two distinct
sensory neuronal systems, the somatic and visceral sensory pathway. A novel and unique spinal sensory system, the spinosolitary
tract-dorsal column postsynaptic neuronal system (SST-DCPS), was physiologically and anatomically identified. The spinal neurons
project to both visceral (the solitary tract nucleus) and somatic sensory (the dorsal column nuclei) nuclei via their branched
axons and receive both visceral and somatic sensory information ascending from periphery through dichotomized primary afferents
and descending from their targets via their branched axons. The brain might thus be aware of both visceral and somatic sensation
via a single SST-DCPS neuronal channel. The finding of SST-DCPS system, as an example, might be considered as an intersection
or fuzzy set of the SST and DCPS system and the concept of dichotomy in classification of neurons and neuronal pathways might
thus be challenged. 相似文献
80.
为进一步阐明脊髓损伤(SCI)的修复机制,对SD成年大鼠进行急性全横断损伤,将损伤前后的大鼠脊髓总蛋白质进行固相pH梯度双向凝胶电泳(2D-PAGE),经考马斯亮蓝染色后,借助PDQuest软件从中找出差异表达蛋白质点.应用基质辅助激光解吸电离串联质谱对差异表达的蛋白质点进行鉴定,成功鉴定出38种蛋白质.其中表达上调的蛋白质有电压依赖的阴离子选择通道蛋白1,α-烯醇酶、硫氧还蛋白依赖的过氧化物还原酶3、生长因子受体结合蛋白2等,表达下调的蛋白质有谷氨酰胺合成酶、14-3-3 epsilon、磷脂酰乙醇胺结合蛋白1、血红蛋白β-1等.鉴定出的差异蛋白多数涉及到神经细胞的增殖、凋亡、应激反应等过程. 相似文献