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91.
Zhuoxin Yang Lihong Diao Haibo Yu Wenshu Luo Ling Wang Min Pi Xiaodan Rao Junhua Peng 《中国神经再生研究》2008,3(1)
BACKGROUND: The onset of focal cerebral ischemia activates extracellular signal-regulated kinases 1 and 2, regulates cell cycle, promotes cell proliferation and differentiation, and affects the normal stage and function of brain cells.OBJECTIVE: To observe the effects of electroacupuncture at the Ren channel on extracellular signal-regulated kinases 1/2 expression in the lateral cerebral ventricle wall of rats with focal cerebral ischemia. The effects were analyzed at different time points after intervention.DESIGN: Randomized controlled study.SETTING: Department of Anatomy, Sun Yat-Sen University. MATERIALS: A total of 60 healthy adult male Wistar rats weighing (250±10) g were provided by the Experimental Animal Center, Medical College of Sun Yat-Sen University. The animal experiment was conducted with confirmed consent by the local ethics committee. The GB6805-Ⅱ electric acupuncture apparatus was provided by Shanghai Medical Equipment High-techno Company. METHODS: The experiment was performed at the Laboratory of Anatomy, Sun Yat-Sen University, from February to July 2007. All experimental animals were randomly divided into the following groups: normal group (n = 6), sham operation group (n = 18), model group (n = 18), and electroacupuncture group (n = 18). Middle cerebral artery occlusion (MCAO) was performed in the model group and electroacupuncture group. Zea Longa's grading standard was used to assess neurological impairment after reperfusion; animals whose grades were between 1 and 4 were included in this study. The normal control group was not exposed to MCAO. In sham operation animals, the right common carotid artery (CCA) was isolated, and the external carotid artery (ECA) was damaged, but no embolism was induced. The electroacupuncture group was given acupuncture on the second day after surgery. The acupoint locations were chosen according to Experimental Acupuncture (People's Publishing House; 1997; First Edition). The Chengjiang, Qihai, and Guanyuan acupoints were labeled and connected to a G6805 electroacupuncture apparatus with sparse-dense waves (sparse waves were 30 Hz, dense waves were 100 Hz), with a frequency of 6-15 V. The duration was 20 minutes. Two days after surgery, the model and sham operation groups were placed with their backs on the operating table, but they received no acupuncture. However, the normal group received acupuncture. The experimental animals under anesthesia were sacrificed on days 7, 14, and 28 post-surgery. Western blot analysis was used to measure expression of extracellular signal-regulated kinases 1/2 in the inferior region of the lateral cerebral ventricle wall. Expression was measured in the normal group at time points corresponding to the sham operation group. MAIN OUTCOME MEASURES: Expression of extracellular signal-regulated kinases 1/2 in the inferior region of the lateral cerebral ventricle wall at different time points after intervention.RESULTS: All 60 rats were included in the final analysis, without any loss. Seven days after MCAO, there was no significant difference in extracellular signal-regulated kinases 1/2 expression in the electroacupuncture group compared to the model group (P > 0.05). However, extracellular signal-regulated kinases 1/2 expression significantly increased in the model group at 14 and 28 days after treatment (P < 0.05).CONCLUSION: Electroacupuncture at the Ren channel can enhance extracellular signal-regulated kinases1/2 expression in the inferior region of the lateral cerebral ventricle wall of rats with focal cerebral ischemia. However, this effect is not apparent until 14 days after electroacupuncture intervention. 相似文献
92.
近年来随着介入技术的不断发展,心房颤动(房颤)的治疗已逐步由药物治疗转向介入治疗,尤其对于药物治疗效果差和症状持续性房颤患者,介入治疗可作为首选。目前存在的治疗房颤的导管消融方式有射频消融术、冷冻消融术、脉冲场消融等。本文旨在对不同消融方式在房颤患者中的治疗现状作一概述。 相似文献
93.
Meichi Wang Jianbo Diao Jiang Li Jianzhou Tang Yin Lin Weijun Hu Yongqun Zhang Yucheng Xiao Songping Liang 《Toxicon》2008,52(8):871-880
Neurotoxins are important tools to explore the structure and function relationship of different ion channels. From the venom of Chinese spider Chilobrachys jingzhao, a novel toxin, Jingzhaotoxin-IV (JZTX-IV), is isolated and characterized. It consists of 34 amino acid residues including six acidic residues clustered with negative charge (pI=4.29). The full-length cDNA of JZTX-IV encodes an 86-amino acid precursor containing a signal peptide of 21 residues, a mature peptide of 34 residues and an intervening sequence of 29 residues with terminal Lys-Gly as the signal of amidation. Under whole-cell patch clamp conditions, JZTX-IV inhibits current and slows the inactivation of sodium channels by shifting the voltage dependence of activation to more depolarized potentials on DRG neurons, therefore, differs from the classic site 4 toxins that shift voltage dependence of activation in the opposite direction. In addition, JZTX-IV shows a slowing inactivation of sodium channel with a hyperpolarizing shift of the steady-state inactivation on acutely isolated rat cardiac cell and DRG neurons, differs from the classic site 3 toxins that do not affect the steady-state of inactivation. At high concentration, JZTX-IV has no significant effect on tetrodotoxin-resistant (TTX-R) sodium channels on rat DRG neurons and tetrodotoxin-sensitive (TTX-S) sodium channels on hippocampal neurons. Our data establish that, contrary to known toxins, JZTX-IV neither binds to the previously characterized classic site 4, nor site 3 by modifying channel gating, thus making it a novel probe of channel gating in sodium channels with potential to shed new light on this process. 相似文献
94.
目的:观察早期卵裂和原核消失在体外受精-胚胎移植(IVF-ET)治疗中的应用价值。方法:①对行IVF-ET治疗的210例239个周期,于受精后18~19h观察受精情况,25~26h观察早期卵裂与原核消失情况,66~68h再进行1次胚胎观察,了解其临床妊娠率和胚胎种植率。②根据移植胚胎中有无早期卵裂或原核消失将患者分为:早期卵裂或原核消失组(139例152个周期)与无早期卵裂或原核消失组(71例87个周期),比较两组优质胚胎率、临床妊娠率和胚胎种植率。结果:①临床妊娠率为42.7%,胚胎种植率为28.9%。②发生早期卵裂的胚胎在受精后第3日的优质胚胎率高于未发生早期卵裂的胚胎(P<0.01);发生2原核消失(2PNBD)胚胎在受精后第3日的优质胚胎率又高于2原核(2PN)持续存在的胚胎(P<0.01)。③有早期卵裂或原核消失组的优质胚胎率(75.5%)、临床妊娠率(44.7%)和胚胎种植率(29.5%)分别高于无早期卵裂或原核消失组(P<0.01)。在早期卵裂或原核消失组,随移植胚胎中发生早期卵裂或原核消失的胚胎数目增加,妊娠率及多胎妊娠率有增加趋势。④受精25~26h,有0.95%的2PN合子变成≥3PN合子;1.37%的2PN合子变成1PN合子;0.83%的1PN合子变成2PN合子。结论:早期卵裂和原核消失可以作为选择移植胚胎的一个指标,可作为辅助生殖技术实验室常规观察项目,提高IVF-ET成功率。 相似文献
95.
Sylla C Diabate I Fall PA Diao B Bah I Gueye SM Ndoye A Ba M Diagne BA 《Annales d'Urologie》2002,36(1):38-41
The authors report five cases of ureterocele during six years. Mean age of the patients was 34.2 +/- 11.1 years. There were four female and one male. Pain (N = 3) and dysuria (N = 3) were the most common symptoms at examination. Diagnosis was made by ultrasound (N = 3), IVU (N = 3) or cystoscopy (N = 1). Ureteroceles were bilateral in four cases, unilateral in one case and were always intravesical with single ureter. Two patients presented lithiasis enclosed in the ureterocele. Only four patients had been operated. Surgical treatment was ureterocelectomy with ureteral reimplantation according to Cohen procedure. With mean follow-up of 10.6 +/- 4.7 months results were stable without complications. 相似文献
96.
Postnatal development of nicotinamide adenine dinucleotide phosphate-diaphorase-positive neurons in the retina of the golden hamster 总被引:1,自引:0,他引:1
The histochemical method was used to investigate the postnatal development of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) -positive neurons in retinas of the golden hamster. NADPH-d-positive neurons were discernible in the retina at postnatal day (P)1. From P4 onward to adulthood, when the retina acquired its laminated characteristics, NADPH-d- positive neurons were observed in the inner nuclear layer (INL) and the ganglion cell layer (GCL). Results showed that NADPH-d-positive neurons in INL and GCL followed different time courses and patterns in their development. NADPH-d-positive neurons in INL underwent a sharp increase from P4 to P8 (3.6-fold), followed by a decrease to 46% of the maximum at P12. This value was maintained relatively constant to the adult level. The mean diameters of NADPH-d-positive neurons in INL, which were smaller than those in the GCL for all ages, increased from P8 to P12 and from P20 to adulthood. As for neurons in the GCL, the increase in cell number was not so apparent for the earlier postnatal days until P20; thereafter, an obvious increase to the adult level was observed. The mean diameters of the NADPH-d-positive cell bodies in the GCL increased with age, except for P16-P20, during which time there was a slight and insignificant decrease. The tendency of changes in cell density was basically similar to that of the total number for both the INL and the GCL. Between P12 and P20, the density distribution map of the NADPH-d-positive neurons underwent dramatic changes: The highest density shifted from the upper central retina at the earlier postnatal days to the lower central retina in the adult. The two waves of increase in NADPH-d-positive neurons coincide with the process of axonal elongation and synaptogenesis and the acquisition of visual function and experience. It is suggested that these NADPH-d-positive neurons are related to these two developmental events. 相似文献
97.
珠海口岸首次截获褐带蠊 总被引:2,自引:0,他引:2
珠海出入境检验检疫局于2003年8月29日从1艘巴拿马籍货轮上捕获1只雌性褐带蠊成虫Supella longipalpa(Fabricius,1798)。该种蜚蠊起源于非洲,在美国是常见室内种,在我国罕见。其主要特征为:有2条淡褐色带状横斑位于翅基部和腹部,因此俗称其为“褐带蠊”。为防止该蜚蠊通过国际航行船舶传入我国,对褐带蠊的形态特征进行描述,以供口岸检疫人员和昆虫研究人员鉴别之用。 相似文献
98.
目的探讨白细胞介素-6(IL-6)和肿瘤坏死因子(TNF)在脑梗死过程中所起的作用和临床意义。方法采用ELISA方法测定42例脑梗死患者和40例同龄健康体检者血清IL-6和TNF含量,并分析它们与梗死体积的关系。结果急性脑梗死患者血清IL-6和TNF明显高于对照组,它们与脑梗死体积存在明显相关性。结论IL-6和TNF参与了急性脑梗死的发生发展。 相似文献
99.
The present study observed the effects of superoxide diamutase (SOD) and its Inhibitor, diethyldithiocarbamate (DDC), on the metastasis of Lewis Lung cancer and some biological characteristics of A548 lung cancer cell line. It was found that SOD and DDC inhibited significantly the metastasis of Lewis lung cancer In C57 BL mice, which the effect of DDC was more significant than that of SOD, and decreased the proliferation of A549 lung cancer cell and its transplantation rate in nude mice. 相似文献
100.