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241.
Yanhong Li Shuanke Wang Yayi Xi Jing Wang Wenjie Pan Yingbin Shi Mige Wang 《中国神经再生研究》2007,2(8):471-474
BACKGROUND: At present, there is still lack of effective drugs for chronic spinal cord injury, whereas it is found recently that estrogen has a neuroprotective effect on brain and spinal cord injuries.
OBJECTIVE: To observe the effect of estrogen on the apoptosis of nerve cells after gradual chronic spinal cord injury in ovariectomized rats.
DESIGN: A randomized controlled animal trial.
SETTING: Institute of Orthopaedics, the Second Hospital of Lanzhou University.
MATERIALS: Sixty-five female Wistar rats of common degree, weighing 220–250 g, were provided by the experimental animal center of Lanzhou University. The rats were randomly divided into sham-operated group (n =5), estrogen-treated group (n =30) and saline control group (n =30), and the latter two groups were observed at 1, 3, 7, 14, 28 and 60 days respectively, and 5 rats for each time point.
METHODS: All the rats were treated with bilateral oophorectomy 2 weeks before the experiment. T10 vertebral lamina was revolved into using plastic screw. The spinal canal impingement was not induced initially. After that, the original incision was opened to expose the screw every 7–10 days.
MAIN OUTCOME MEASURES: The apoptosis and Caspase-3 positive cells in the damaged spinal cord were detected using terminal deoxynucleotidal transferase-mediated dUTP-biotin nick end labeling (TUNEL) method and Caspase-3 immunohistochemical staining at 1, 3, 7, 14, 28 and 60 days after chronic spinal cord injury respectively.
RESULTS: Totally 65 rats were used, and the deleted ones during the experiment were supplemented by others. Changes of Caspase-3 expression after spinal cord injury: In the sham-operated group, only a small amount of Caspase-3 proteins were observed in the rat spinal cord, mainly located in motor neurons of spinal cord anterior horn. In the estrogen-treated group and saline control group, positive cells expressed occasionally at 1 day postoperatively, began to increase obviously at 7 days after injury, strongly expressed at 14 and 28 days, but decreased at 60 days, mainly located in the neurons of spinal cord gray matter anterior horn, and they expressed fewer in the motor neurons and white matter of ventral horn, and there were obvious differences between the estrogen-treated group and saline control group at 7, 14, 28 and 60 days (P < 0.05).
CONCLUSION: Estrogen can reduce the apoptosis of nerve cells and promote the recovery of neurological function following gradual chronic spinal cord injury. 相似文献
242.
勃起功能障碍与血管内皮功能关系的研究进展 总被引:4,自引:2,他引:2
血管内皮功能在阴茎勃起过程中扮演了十分重要的角色,血管内皮功能障碍是ED的病理基础之一。测量肱动脉血流介导的血管扩张功能是目前血管内皮功能主要的评估方法。改善血管内皮功能的治疗能改善阴茎勃起功能。ED是心血管疾病的先兆,及早发现ED并给予适当治疗,在改善生活质量的同时有助于降低未来心血管疾病的风险。 相似文献
243.
Objective To observe effects of penetrating cornea injury combined with seawater immersion on the levels of aqueous humor TNF-α in rabbits. Methods 10 adult healthy grey rabbits were used for the experiment. The rabbit eye model of comea blast injury was developed by using a single firecracker. For each rabbit, the right eye was the experimental eye (seawater was injected into the anterior chamber through the cornea incision, simulating seawater immersion) and the left eye was the control (treated with 0.9% sodium chloride). Levels of aqueous humor TNF-α were detected by using double-antibody sandwich ELISA on the 1st, 2nd, yrd, 4th, 5th, and 7th days following seawater immersion or 0.9% sodium chloride injection. Results Following development of the model, levels of aqueous humor TNF-α in the experimental eye on the 1st, 2nd, 3rd days were 190.338, 156. 107,117.018 ng/L respectively, and significant differences could be seen when comparisous were made between the experimental and control eyes. The level of aqueous humor TNF-α on the 1st day was the highest and obviously reached the peak. Conclusions Level of aqueous humor TNF-α in the experimental eye with penetrating cornea injury combined with seawater immersion was significantly higher than that of the control eye, indicating that TNF-α was clearly involved in the pathological change and it played an important role in the process. 相似文献
244.
目的探讨MR流量测量与不同感兴趣区(ROI)直径的关系。方法使用Philips 1.5T双梯磁共振机流量测定程序,测量2mm内径塑胶管中不同流量的水(0.5、1.0、1.5、2.0、2.5ml/s),不同流向(流入及流出方向)、不同ROI位置(测量图中心区和偏中心区)与不同的ROI直径(直径0.5、1.0、1.5、2.0mm)流量变化关系,统计计算标准的ROI直径。结果在不同流量、流向和测量位置中,流量与ROI直径大小存在明显的直线相关(r>0.95,P<0.05),ROI直径大小显著地影响测量结果,当ROI直径取值等于测量图直径的0.6040±0.0480时,所测结果与实际流量一致。在不同流量下的不同流向及ROI位置对流量测定无影响(P>0.05)。结论对直径2mm流量测定,应选取测量图上直径的0.6040±0.0480 ROI进行。 相似文献
245.
目的:总结大样本病例64排螺旋CT冠状动脉成像中发现的冠状动脉变异类型及数量,为临床诊治提供依据,积累冠状动脉活体形态学资料,提高对冠状动脉变异的认识。方法:对694例受检者进行心脏冠脉成像检查,并对其图像进行回顾性分析。结果:694例受检者中,44例发现4种不同类型冠状动脉变异,占总数6.34%。其中副冠状动脉33例,RCA起源于左窦2例,LCX起源于右窦7例,左冠状动脉开口异常2例。结论:64排螺旋CT冠状动脉成像可以无创观察冠状动脉解剖及变异,为临床治疗提供依据。对冠状动脉细小分支的显示及对冠状动脉变异的认识有待提高。 相似文献
246.
多层螺旋CT对冠状动脉粥样硬化斑块的显示结果及与超声结果的比较 总被引:6,自引:0,他引:6
目的评价多层螺旋CT(MSCT)探查无明显管腔狭窄的冠状动脉粥样硬化斑块的能力及准确性。方法共35例连续患者行冠状动脉内超声(IVUS)及16层MSCT检查,其中30例MSCT成像成功。对94支无明显狭窄的冠状动脉节段MSCT及IVUS图像行对照研究,逐一分析每支冠状动脉节段是否出现粥样硬化斑块。IVUS根据斑块回声特点将斑块分为钙化斑块、纤维斑块和软斑块,MSCT则测量斑块密度,以CT值表示。结果对照IVUS结果,MSCT对出现任何粥样硬化斑块节段的诊断敏感性为82.1%(46/56),特异性为89.5%(34/38)。对于含钙化斑块的节段,MSCT诊断敏感性为92.1%(35/38),特异性为96.4%(54/56)。对于含非钙化斑块的节段,MSCT诊断敏感性为73.2%(30/41),特异性为88.7%(47/53)。对于仅含非钙化斑块的节段,MSCT诊断敏感性为66.7%(12/18)。MSCT分析54个斑块平均CT值,按照IVUS分类,钙化斑块19个,纤维斑块19个,软斑块16个,对应CT值分别为:钙化斑块(489±169)HU(196~817HU),纤维斑块(69±21)HU(25~117HU)以及软斑块(23±18)HU(-12~47HU)。非参数Kruskal-Wallis检验显示3组斑块MSCT测量密度CT值间差异有统计学意义(P值均〈0.01);两种方法对斑块面积的测量具有相关性(r=0.58,P〈0.01),MSCT测定斑块平均面积为5.3mm^2,IVUS为5.6mm^2。结论MSCT对无明显管腔狭窄的冠状动脉粥样硬化斑块有良好的探查能力。根据斑块密度(CT值)差异,MSCT能区分不同类型冠状动脉粥样斑块。对斑块面积测量,MSCT与IVUS结果具有相关性。 相似文献
247.
单甲氧聚乙二醇化学修饰药物酶的研究进展 总被引:4,自引:0,他引:4
用单甲氧基聚乙二醉(1)化学修饰药物酶是生化药物研究开发的重要手段之一。本文综述了1化学修饰药物酶的一般方法及修饰后酶在生物和理化性质方面的变化,同时对1研究前景进行展望,并指出了尚待解决的问题。 相似文献
248.
Garth Bissette Violetta Klimek Jun Pan Craig Stockmeier Gregory Ordway 《Neuropsychopharmacology》2003,28(7):1328-1335
Research evidence that corticotropin-releasing factor (CRF) plays a role in the pathophysiology of major depressive disorder (MDD) has accumulated over the past 20 years. The elevation of lumbar cerebrospinal fluid (CSF) concentrations of CRF decreased responsiveness of pituitary CRF receptors to challenge with synthetic CRF, and increased levels of serum cortisol in MDD subjects support the hypothesis that CRF is chronically hypersecreted in at least the endocrine circuits of the hypothalamic-pituitary-adrenal (HPA) axis and may also involve other CRF brain circuits mediating emotional responses and/or arousal. One such circuit includes the excitatory CRF input to the locus coeruleus (LC), the major source of norepinephrine in the brain. Furthermore, there are now reports of decreased levels of CRF in lumbar CSF from MDD patients after symptom relief from chronic treatment with antidepressant drugs or electroconvulsive therapy. Whether this normalization reflects therapeutic effects on both endocrine- and limbic-associated CRF circuits has not yet been effectively addressed. In this brief report, we describe increased concentrations of CRF-like immunoreactivity in micropunches of post-mortem LC from subjects with MDD symptoms as established by retrospective psychiatric diagnosis compared to nondepressed subjects matched for age and sex. 相似文献
249.
Transient Macular Edema after Laser In-Situ Keratomileusis 总被引:8,自引:0,他引:8
Bin Yang Zheng Wang Guofu Huang Xing Liu Yunlan Ling Xiaoping ZhengZhongshan Ophthalmic Center Sun Yat-sen University Guangzhou China 《眼科学报》2003,19(1):20-24
Purpose: To investigate the macular changes induced by laser in situ keratomileusisc(LASIK) procedure.Methods: Optical Coherence Tomography (OCT) was used to examine 27 eyes of 15LASIK patients before surgery, and 1 day, 1 week, 1 month after surgery.Results: The mean thick iness of neuroepithelial layer of macula was (195 ±24)microns, (178± 16) microns 1 day and 1 month after surgery, respectively, while thebaseline was (174 ± 12) microns. The increase in macular neuroepithelial thickness wascorrelated with the degree of myopia, but not with the duration of suction or thepostoperative BCVA.Conclusion: Mild macular edema is common in the first month following LASIK,especially in high myopia. However, no association with loss of BCVA has beenestablished. Eye Science 2003; 19: 20 - 24. 相似文献
250.
报告37例主动脉窦瘤破裂手术治疗结果。着重介绍手术方法,主张采用主动脉根部和窦瘤破入心腔的双切口,切除、修补窦瘤的同时矫正合并畸形。伴主动脉瓣膜垂致中度关闭不全者,主张行主动脉瓣替换术。术后早期死亡1例,余35例随访6个月-14年,心功能恢复良好。 相似文献