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121.
Shaoyi Chen Coleen M Atkins Chunli L Liu Ofelia F Alonso W Dalton Dietrich Bingren R Hu 《Journal of cerebral blood flow and metabolism》2007,27(5):939-949
In response to traumatic brain injury (TBI), neurons initiate neuroplastic processes through the activation of intracellular signaling pathways. However, the molecular mechanisms underlying neuroplasticity after TBI are poorly understood. To study this, we utilized the fluid-percussion brain injury (FPI) model to investigate alterations in the mammalian target of rapamycin (mTOR) signaling pathways in response to TBI. Mammalian target of rapamycin stimulates mRNA translation through phosphorylation of eukaryotic initiation factor 4E binding protein-1 (4E-BP1), p70 ribosomal S6 kinase (p70S6K), and ribosomal protein S6 (rpS6). These pathways coordinate cell growth and neuroplasticity via dendritic protein synthesis. Rats received sham surgery or moderate parasagittal FPI on the right side of the parietal cortex, followed by 15 mins, 30 mins, 4 h, 24 h, or 72 h of recovery. Using Western blot analysis, we found that mTOR, p70S6K, rpS6, and 4E-BP1 phosphorylation levels were significantly increased in the ipsilateral parietal cortex and hippocampus from 30 mins to 24 h after TBI, whereas total protein levels were unchanged. Using confocal microscopy to localize these changes, we found that rpS6 phosphorylation was increased in the parietal cortex and all subregions of the hippocampus. In accordance with these results, eIF4E, a key, rate-limiting mRNA translation factor, was also phosphorylated by mitogen-activated protein kinase-interacting kinase 1 (Mnk1) 15 mins after TBI. Together, these results suggest that changes in mRNA translation may be one mechanism that neurons use to respond to trauma and may contribute to the neuroplastic changes observed after TBI. 相似文献
122.
清心莲子饮加减降低肾性血尿复发率临床观察 总被引:1,自引:0,他引:1
目的:探讨降低慢性原发性肾小球性血尿复发率的有效方法。方法:将经过治疗血尿转阴的慢性原发性肾小球性血尿患者52例,随机分为治疗组和对照组各26例,治疗组延长疗程,用清心莲子饮加减巩固治疗3个月,对照组停用药物治疗,嘱其注意休息,调畅情志,避免吃辛辣刺激食品。结果:两组疗效有显著性差异(P<0.05),治疗组复发率明显降低。结论:延长疗程,用清心莲子饮加减巩固治疗,具有降低慢性原发性肾小球性血尿复发率的显著作用。 相似文献
123.
Hongning Zhao Xiaoming Wang Junqiang Zhang Deben Yang Xiaoqiong Zhao Xin Liu Hui Huang Jianxiu Hu 《中国神经再生研究》2007,2(11):675-677
BACKGROUND: The examination of sympathetic skin response is an important index for assessing the autonomic nerve function, and patients with myasthenia gravis are always accompanied by dysautonomia. Therefore, it will be important to know whether sympathetic skin response can be used as the index for the clinical evaluation of myasthenia gravis.
OBJECTIVE: To investigate the diagnostic value of sympathetic skin response in the damage of autonomic nerve function of patients with myasthenia gravis.
DESIGN: A case-controlled comparative observation.
SETTING: Department of Neurology and Room of Nerve Electromyogram, the Affiliated Hospital of North Sichuan Medical College.
PARTICIPANTS: Thirty outpatients or inpatients with myasthenia gravis were selected from the Department of Neurology, the Affiliated Hospital of North Sichuan Medical College from May 2006 to May 2007, including 9 males and 21 females, aged 8–72 years with a mean age of (28±5) years old. They were all accorded with the diagnostic standards of myasthenia gravis, accompanied by different severity of autonomic nerve symptoms, including poor skin nutrition, sweating of hands and feet, pyknocardia, persistent hypotension, abdominal pain, constipation, etc. They all had not taken any drug affecting the autonomic nerve function before the examination. Informed consents were obtained from all the patients. Meanwhile, 30 healthy physical examinees were enrolled as the normal control group, including 10 males and 20 females, aged 10–75 years with a mean age of (31±5) years old. Approval was obtained from the hospital ethic committee.
METHODS: After admission, the patients were examined with sympathetic skin response using DANTEC keypoint 2.0 electromyography evoked potential apparatus (Danmark). The changes of the latency and wave amplitude of sympathetic skin response were observed. The subjects in the normal control group were examined with the same methods at physical examination. Abnormality was judged by the disappearance of wave form, latency longer than that in the normal control group by Mean±2.5SD, or wave amplitude lower than the average value in the normal control group by 50%.
MAIN OUTCOME MEASURES: The results of the latency and wave amplitude of sympathetic skin response were compared between the patients with myasthenia gravis and normal controls.
RESULTS: All the 30 patients with myasthenia gravis and 30 healthy physical examinees were involved in the final analysis of results. There were no significant differences between the left and right upper and lower limbs in both the myasthenia gravis group and normal control group (P > 0.05). In the myasthenia gravis group, the abnormal rate of sympathetic skin response was 37% (11/30), the latency was prolonged and the wave amplitude was decreased as compared with those in the normal control group, and there were significant differences (P < 0.01).
CONCLUSION: Sympathetic skin response can be used as an electrophysiological index for judging the damages of autonomic nerve function in patients with myasthenia gravis. 相似文献
124.
目的:探讨分叉带锁髓内钉治疗肱骨干骨折临床经验。方法:采用顺行和逆行分叉肱骨带锁髓内钉治疗肱骨干骨折25例。结果:随访平均26个月,优16例,良7例,可2例,优良率92%。除肩关节活动受限2例外,其余均完全恢复肩关节和肘关节功能。结论:分叉带锁髓内钉适应于肱骨骨折,其坚强-动态固定的有机结合有利于骨折的愈合。方法简单,固定可靠,创伤小,是一种较好的手术方法。 相似文献
125.
Exogenous advanced glycosylation end products induce diabetes-like vascular dysfunction in normal rats: a factor in diabetic retinopathy 总被引:2,自引:0,他引:2
Xun Xu Zhiping Li Dawei Luo Yufeng Huang Jianfeng Zhu Xiaojue Wang Honghui Hu C. Patrick 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2003,241(1):56-62
BACKGROUND. Diabetic retinopathy has been shown to be directly associated with the degree and duration of hyperglycemia, and advanced glycosylation end products (AGEs) have been implicated in this pathological process. The purpose of the experiments reported here was to study the effect of AGE deposition on retinal vascular damage which leads to diabetic retinopathy. METHODS. Intravenous injection of exogenous AGEs was used to treat wild-type non-diabetic Sprague-Dawley rats. One of the two retinal slides from each animal was treated using immunohistochemical staining to label retinal vascular AGE deposition, the other H&E staining for counting of capillary pericytes. The results were compared with the findings in untreated wild-type and diabetic controls and in rats treated with unmodified rat serum albumin (RSA). RESULTS. After 2 weeks of continuous treatment, AGEs were identified in the retinal vascular tissue of the AGE-RSA-injected group. The average number of retinal capillary pericytes per 10x100 microscope power field was 4.313+/-0.34 (mean +/- SD) in the AGE-RSA-injected group, compared with 5.798+/-0.481 in the control group ( P<0.01). CONCLUSION. These experiments demonstrate that AGEs, independent of other metabolic factors, can induce vascular change resembling that of diabetic retinopathy. 相似文献
126.
127.
目的总结初步使用国产TC-Dynamic人工膝关节系统的临床效果和手术经验。方法本组使用国产TC—Dynamic人工膝关节行全膝关节置换术(TKA)40例60膝,术前膝关节外科学会评分(KSS)的膝评分平均为16.28分(-32~47分),功能评分平均为18.36分(-20~60分),膝关节活动度(ROM)平均为79.22°(20°~145°)。结果36例52膝术后获得平均随访时间为20.41m(1.5~40m),随访时KSS膝评分平均为84.88分(70~95分),功能评分平均为80.58分(55~90分),ROM平均为110.48°(85°~140°)。所有随访患者术后X线片均示下肢力线良好,假体位置满意,无透亮线及任何松动迹象。结论使用国产TC—Dynamic人工膝关节假体的TKA手术临床效果满意。手术操作简便,截骨量较少,如果手术配套器械的设计和制作工艺能够进一步改良和提高,则更利于临床应用。 相似文献
128.
129.
鼻内镜下鼻中隔成形术临床应用观察 总被引:1,自引:0,他引:1
目的探讨鼻内镜下鼻中隔成形术的优点.方法鼻内镜下行鼻中隔成形术50例,其中高位和后段偏曲6例.结果50例均一次完成手术,偏曲的鼻中隔均获得彻底矫正.手术时间30~72 min,平均48 min,偏进的鼻中隔获得彻底矫正,随访6~9个月,平均7.1月,治愈45例(90%),好转5例(10%).无鼻中隔血肿、脓肿、穿孔、鼻腔粘连、鼻梁塌陷等并发症发生.结论鼻内镜下鼻中隔成形术,手术时间短,术中出血少,疼痛轻,术后并发症少,可同期行鼻窦手术,完全可以取代传统的鼻中隔黏膜下切除术. 相似文献
130.
Xin Wang Ji-Ming Hu I-Ming Hsing 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2004,562(1):73-80
This work studies formic acid as an anode fuel for polymer electrolyte fuel cells and investigates the electro-oxidation of formic acid on Pt/C. Fuel crossovers through the Nafion® 115 membrane at different temperatures and concentrations are reported. A linear dependence of the crossover current on the temperature and concentration is obtained. It is found that the crossover can be reduced by five times and a higher performance can be rendered by formic acid when compared to methanol under the same conditions. Electrochemical impedance measurements are conducted to interpret the reaction mechanism of formic acid oxidation. The effect of the electrode potential on the impedance pattern is revealed and an impedance model incorporating the reaction kinetics information is developed to simulate the experimental impedance response. 相似文献