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目的:研究TGFBI和微管相关蛋白轻链3(LC3)在角膜营养不良患者中的表达,及氯化锂(LiCl)通过TGFBI对角膜基质成纤维细胞增殖能力的影响。
方法:用免疫组化和Western-blot方法检测角膜营养不良及正常角膜组织中TGFBI和LC3的表达。实验构建了TGFBI过表达载体并转染角膜基质成纤维细胞,分别以5、10、20、40mmol/L LiCl作用于突变型TGFBI转染的角膜基质成纤维细胞,检测不同时间(0、1、6、12h)后,TGFBI与LC3蛋白表达变化,并用CCK-8法检测细胞增殖活性。
结果:TGFBI和LC3在角膜营养不良患者角膜组织中显著高表达。TGFBI过表达抑制角膜基质成纤维细胞增殖活性(P<0.05)。LiCl抑制突变型TGFBI转染的角膜基质成纤维细胞中TGFBI和LC3蛋白表达,并增强其细胞增殖活性(P<0.05)。
结论:LiCl可以促进角膜基质成纤维细胞增殖活性和自噬,其作用机制与下调TGFBI和LC3的表达有关。 相似文献
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聂莉芳教授是国家级名老中医、中医肾病专家。聂教授认为慢性肾脏病的病因病机属本虚标实,常挟热、挟湿、挟瘀,故临床遣方用药宜正邪兼顾,临床诊治时常在益气养阴的基础上加用清热利湿化瘀之品。生石膏是聂教授临床上常用的清热药之一。聂教授临床应用生石膏并灵活配伍治疗多种慢性肾脏病,疗效满意,值得后辈继承和发扬。 相似文献
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In this study, heparin-like poly(ethersulfone) (HLPES) was synthesized by a combination of polycondensation and post-carboxylation methods, and was characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance hydrogen spectrum and gel permeation chromatography. Owing to the similar backbone structure, the synthesized HLPES could be directly blended with pristine PES at any ratios to prepare PES/HLPES membranes. After the introduction of HLPES, the microscopic structure of the modified PES membranes was changed, while the hydrophilicity was significantly enhanced. Bovine serum albumin and bovine serum fibrinogen adsorption, activated partial thromboplastin time, thromb time and platelet adhesion for the modified PES membranes were investigated. The results indicated that the blood compatibility of the PES/HLPES membranes was significantly improved compared with that of pristine PES membrane. For the PES/HLPES membranes, obvious decreases in platelet activation on PF-4 level, in complement activation on C3a and C5a levels, and in leukocytes activation on CD11b levels were observed compared with those for the pristine PES membrane. The improved blood compatibility of the PES/HLPES membrane might due to the existence of the hydrophilic groups (–SO3Na, –COONa). Furthermore, the modified PES membranes showed good cytocompatibility. Hepatocytes cultured on the PES/HLPES membranes presented improved growth in terms of SEM observation, MTT assay and confocal laser scanning microscope observation compared with those on the pristine PES membrane. These results indicate that the PES/HLPES membranes present great potential in blood-contact fields such as hemodialysis and bio-artificial liver supports. 相似文献
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目的评价"NS动静态心电分析系统"的NS-DII型产品远程心电实时采集、传输以及心电图数据回放的准确性、可靠性及临床使用价值。方法采用"NS动静态心电分析系统"的NS-DII型产品对我院100例患者进行心电数据的采集,再与已经临床注册,广泛使用的GE-3500型心电图机作为对照设备。通过两个不同设备在同一时间段,同一检测条件下对同一患者检测到的心电数据进行分析。结果 95例患者采用NS-DII型"NS动静态心电分析系统"进行的心电信号的采集和心电图数据无线实时上传及跟踪回放心电图均成功。试验中对其回放12导联心电图与GE-3500型心电图机所描记的心电图作对照分析,两个不同设备所检测到的心电数据包括心率、P-QRS-T波的时限和电压及ST段偏移等关键性技术指标上进行分析无统计学差异(p>0.05)。结论 "NS动静态心电分析系统"的NS-DII型产品是一种新型的心电监测与分析仪器,其远程心电实时采集、传输以及心电图数据回放准确、可靠。该产品适用于院内和院外心电信息的诊断和会诊。 相似文献
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Over the vast Northwest China, arid desert contains high concentrations of sulfate, chloride, and other chemicals in the ground water, which poses serious challenges to infrastructure construction that routinely utilizes portland cement concrete. Rapid industrialization in the region has been generating huge amounts of mineral admixtures, such as fly ash and slags from energy and metallurgical industries. These industrial by-products would turn into waste materials if not utilized in time. The present study evaluated the suitability of utilizing local mineral admixtures in significant quantities for producing quality concrete mixtures that can withstand the harsh chemical environment without compromising the essential mechanical properties. Comprehensive chemical, mechanical, and durability tests were conducted in the laboratory to characterize the properties of the local cementitious mineral admixtures, cement mortar and portland cement concrete mixtures containing these admixtures. The results from this study indicated that the sulfate resistance of concrete was effectively improved by adding local class F fly ash and slag, or by applying sulfate resistance cement to the mixtures. It is noteworthy that concrete containing local mineral admixtures exhibited much lower permeability (in terms of chloride ion penetration) than ordinary portland cement concrete while retaining the same mechanical properties; whereas concrete mixtures made with sulfate resistance cement had significantly reduced strength and much increased chloride penetration comparing to the other mixtures. Hence, the use of local mineral admixtures in Northwest China in concrete mixtures would be beneficial to the performance of concrete, as well as to the protection of environment. 相似文献
70.
Christopher Phillips Sarah J. Shepherd Amy Nowack Kaibao Nie Chris R.S. Kaneko Jay T. Rubinstein Leo Ling James O. Phillips 《Journal of the Association for Research in Otolaryngology》2016,17(1):19-35
Implanted vestibular neurostimulators are effective in driving slow phase eye movements in monkeys and humans. Furthermore, increases in slow phase velocity and electrically evoked compound action potential (vECAP) amplitudes occur with increasing current amplitude of electrical stimulation. In intact monkeys, protracted intermittent stimulation continues to produce robust behavioral responses and preserved vECAPs. In lesioned monkeys, shorter duration studies show preserved but with somewhat lower or higher velocity behavioral responses. It has been proposed that such changes are due to central adaptive changes in the electrically elicited vestibulo-ocular reflex (VOR). It is equally possible that these differences are due to changes in the vestibular periphery in response to activation of the vestibular efferent system. In order to investigate the site of adaptive change in response to electrical stimulation, we performed transtympanic gentamicin perfusions to induce rapid changes in vestibular input in monkeys with long-standing stably functioning vestibular neurostimulators, disambiguating the effects of implantation from the effects of ototoxic lesion. Gentamicin injection was effective in producing a large reduction in natural VOR only when it was performed in the non-implanted ear, suggesting that the implanted ear contributed little to the natural rotational response before injection. Injection of the implanted ear produced a reduction in the vECAP responses in that ear, suggesting that the intact hair cells in the non-functional ipsilateral ear were successfully lesioned by gentamicin, reducing the efficacy of stimulation in that ear. Despite this, injection of both ears produced central plastic changes that resulted in a dramatically increased slow phase velocity nystagmus elicited by electrical stimulation. These results suggest that loss of vestibular afferent activity, and a concurrent loss of electrically elicited vestibular input, produces an increase in the efficacy of a vestibular neurostimulator by eliciting centrally adapted behavioral responses without concurrent adaptive increase of galvanic afferent activation in the periphery. 相似文献