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991.
目的研究补体旁路途径(alternative complement pathway)过度活化在恶性高血压肾硬化中的作用。方法(1)选取本院经肾穿刺活检证实为恶性高血压肾硬化患者50例为病例组,零点行肾穿刺活检的供肾者25例为正常对照组,采用酶联免疫吸附法(ELISA)检测血浆及尿液中的补体旁路途径活化起始B因子、正向调节P因子、负向调节H因子及补体活化终末产物C3a、C5a水平。(2)免疫组化法检测补体活化终末产物C5b-9、C4d及凝集素途径活化产物甘露糖结合凝集素(MBL)在肾活检组织的沉积;免疫荧光双染检测C5b-9与CD34(内皮细胞标志物)在小动脉内皮及肾小球毛细血管内皮的沉积。结果(1)恶性高血压肾硬化患者血浆及尿液中补体B因子、P因子、C3a及C5a均高于正常对照组(均P<0.05),而H因子则低于正常对照组(P<0.05)。(2)恶性高血压肾硬化患者血浆中补体P因子与24 h尿蛋白量呈正相关(rs=0.465,P=0.001),而补体B因子、H因子、C3a、C5a与血肌酐及24 h尿蛋白量无明显相关性。恶性高血压肾硬化患者尿B因子/尿肌酐、尿P因子/尿肌酐、尿C3a/尿肌酐与血肌酐均呈正相关(rs=0.483,P<0.001;rs=0.352,P=0.012;rs=0.319,P=0.024),尿H因子/尿肌酐与血肌酐及24 h尿蛋白量均呈负相关(rs=-0.299,P=0.035;rs=-0.342,P=0.015),尿C5a/尿肌酐与血肌酐及24 h尿蛋白量均呈正相关(rs=0.525,P<0.001;rs=0.496,P<0.001)。(3)免疫组化显示,恶性高血压肾硬化患者C5b-9沉积于小动脉壁及肾小球毛细血管壁,而正常对照组肾组织中未见沉积。恶性高血压肾硬化患者肾脏C5b-9沉积强度评分与血肌酐及24 h尿蛋白量呈正相关(rs=0.791,P<0.001;rs=0.345,P=0.014)。双重免疫荧光标记法可见C5b-9、CD34沉积于小动脉内皮及肾小球毛细血管内皮。(4)恶性高血压肾硬化患者血浆中B因子与C3a(r=0.331,P=0.022)、P因子与C5b-9评分(rs=0.300,P=0.034)均呈正相关;尿液中补体旁路途径活化B因子与C3a、C5a及C5b-9均呈正相关(rs=0.311,P=0.028;rs=0.465,P=0.001;rs=0.428,P=0.002),P因子与C3a、C5a也均呈正相关(rs=0.307,P=0.030;rs=0.442,P=0.001)。恶性高血压肾硬化患者免疫组化可见C4d沉积于小动脉及肾小球,而未见凝集素途径活化产物MBL沉积。结论补体旁路途径过度活化可能参与恶性高血压肾硬化的发生。恶性高血压肾硬化严重程度与补体旁路途径的活化水平相关。 相似文献
992.
目的:总结斜外侧腰椎椎间融合术(oblique lateral interboy fusion,OLIF)治疗腰椎退行性疾病并发血管损伤的原因并提出预防措施。方法:回顾性分析2014年10月至2017年5月在5家医院接受OLIF手术联合或不联合后路椎弓根钉棒系统内固定治疗腰椎退行性疾病235例患者的病例资料,男79例,女156例;年龄32~83(61.9±13.5)岁。7例出现血管损伤,其中4例节段血管损伤,1例左髂总动脉损伤,1例左髂总静脉损伤,1例卵巢静脉损伤。结果:失访5例(单纯OLIF 2例,OLIF联合后路椎弓根螺钉固定3例),其余获得随访,时间6~36(15.6±7.5)个月,随访过程中未出现椎弓根螺钉松动或断裂现象。患者腰痛VAS评分由术前的(6.7±2.3)分降至末次随访时的(1.4±0.8)分(t=7.21,P=0.033);ODI指数由术前的(36.5±7.7)%恢复至末次随访时的(9.4±3.6)%(t=8.11,P=0.025)。结论:斜外侧腰椎融合技术为微创腰椎内固定融合术提供了一种新的方法,但在其广泛应用的同时尚存在并发血管损伤的风险。术前应严格掌握手术适应证,术中要谨慎细致操作,才能有效预防血管损伤的发生。 相似文献
993.
低能量氦—氖激光血管内照射对血液流变学性质的影响 总被引:1,自引:0,他引:1
目的观察低能量氦—氖激光血管内照射后血液流变学指标的变化,探讨其对高粘血症及缺血性脑血管病的治疗机理。方法采用天津军辉科技开发公司生产的JGL—4D型激光治疗仪,波长为6328nm,功率15mw,每次60分钟,每日一次,10~12天为一疗程。统计学处理采用t检验。结果治疗后,全血粘度、血浆粘度、红细胞压积、纤维蛋白原都明显下降。经t检验P<005。结论此方法能降低血液粘度,改善缺血性脑血管病症状。是一种操作方法简单,无任何副作用的新疗法,值得推广应用。 相似文献
994.
Regulation of opticin on bioactivity of retinal vascular endothelial cells cultured in collagen
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AIM: To investigate the effects of collagen and opticin on the bioactivity of human retinal vascular endothelial cells (hRVECs), and explore its regulations by integrins and RhoA/ROCK1 signal pathway.
METHODS: hRVECs were cultured in collagen and treated by opticin, and cell-based bioactivity assays of cell proliferation, migration, and adhesion were performed. The expression of integrin α2, integrin β1, RhoA and ROCK1 were examined with real-time PCR and Western blotting.
RESULTS: Collagen could promote cell viability of proliferation and migration (all P<0.05), and enhance the mRNA expression of integrin α2, integrin β1, RhoA and ROCK1 (all P<0.05). Opticin could inhibit proliferation and migration ability of hRVECs cultured in collagen, and reduce the mRNA expression of integrin α2, integrin β1, RhoA and ROCK1 (all P<0.05).
CONCLUSION: Collagen and opticin can affect bioactivity of hRVECs, which may be regulated by α2-, β1-integrins and RhoA/ROCK1 signal pathway. 相似文献
995.
De-Gang Xing Yan Zhang Gan-Jian Lin Yang-Yin Xie Shu-Yong Deng Hong-Liang Huang Guang-Bin Jiang Yun-Jun Liu 《Medicinal chemistry research》2014,23(10):4376-4382
A new Ru(II) complex [Ru(dmb)2(AHPIP)](ClO4)2 (Ru1) was synthesized and characterized by elemental analysis, electrospray ionization mass spectra, and 1H NMR and 13C NMR. The cytotoxicity in vitro toward BEL-7402, HeLa, MCF-7, and MG-63 cells was studied by MTT method. The complex shows moderate cytotoxic activity and the IC50 values are 20.2 (±1.6), 16.8 (±1.3), 39.9 (±2.5), and 46.7 (±2.0) μM toward BEL-7402, HeLa, MCF-7, and MG-63 cell lines, respectively. Apoptosis was studied by acridine orange/ethidium bromide staining and flow cytometry. The cellular uptake showed that the complex can enter into the cytoplasm. The cell cycle arrest showed that Ru1 inhibits the proliferation of BEL-7402 cells in the G0/G1 phase. In addition, the antioxidant activity of the complex against hydroxyl radical (·OH) was also investigated. 相似文献
996.
目的:利用DUE模式,评价亚胺培南临床使用规范性、合理性,为临床规范合理使用提供参考。方法依据卫生部《2012年全国抗菌药物临床应用专项整治活动方案》、卫生部2012年《抗菌药物临床应用管理办法》、2011年《抗菌药物临床应用指导原则》、亚胺培南使用说明、有关文献等,制定“亚胺培南临床使用DUE标准”。并依据该标准对某医院2013年住院患者使用亚胺培南196例次病历进行抗菌药物管理、用药指征、用药过程、治疗结果4个方面进行回顾性分析、统计、总结。结果①管理项:微生物送检率70.4%(80%);处方权限符合率91.3%(100%);②用药指征:适合率85.2%(90%);③用药过程:给药途径、溶媒选择、配伍禁忌正确率100%(100%);滴注时间医嘱未注明无法评价;疗效监测项符合率52.0%(85%);老人及肾功能损伤4例未进行剂量调整。④用药结果有效率73%(80%)。结论某医院亚胺培南临床使用与多项预期目标值存在一定差距。医院应针对存在问题进行干预和整改,确保抗菌药物的规范合理使用。认为“亚胺培南临床使用DUE标准”对临床规范、合理使用亚胺培南有一定促进作用。 相似文献
997.
Han Zhang Shou-Xin Yuan Shu-Yang Dai Jin-Min Zhang Xing Huang Chong-De Lu Jun-Hua Lu Fu-Quan Wu Wan Yee Lau Meng-Chao Wu Tian Yang Feng Shen 《World journal of surgery》2014,38(4):947-957
Objective
The aim of this study was to investigate the prognostic value of tumor size alone on long-term survival and recurrence after curative resection for solitary hepatocellular carcinoma (HCC) without macroscopic vascular invasion.Methods
A single-center cohort of 615 patients with solitary HCC (a single tumor, without macroscopic vascular invasion or distant metastasis) undergoing curative hepatic resection from 2002 to 2010 was retrospectively studied. Using 2.0, 3.0, 4.0, 5.0, 8.0, and 10.0 cm as cut-off values of tumor size, the overall survival (OS) and recurrence-free survival (RFS) rates were compared between the groups of patients with tumor size up to a certain cut-off value and the groups of patients with tumor size above that cut-off value. Thus, multiple comparisons were done. The prognostic factors of OS and RFS were evaluated using univariate and multivariate analyses.Results
The median tumor size of all HCCs was 4.0 cm (range 0.9–22.0 cm). The in-hospital mortality rate was 1.0 %, and the overall morbidity rate was 22.3 %. The 1-, 3-, and 5-year OS rates were 96.0, 79.8, and 69.9 %, and the corresponding RFS rates were 83.6, 72.7, and 57.2 %, respectively. On univariate analyses, the 1-, 3-, and 5-year OS and RFS rates were significantly different between the individual two groups of patients as divided by the aforementioned different cut-off values of tumor sizes (all p < 0.05). However, when tumor size was put as a continuous variable into multivariate analysis, it was no longer an independent prognostic factor of OS or RFS after curative resection.Conclusions
Tumor size did not independently affect long-term survival and recurrence after curative resection of solitary HCC without macroscopic vascular invasion. Therefore, there is no size limit that precludes hepatic resection for solitary HCC, provided the tumor is resectable. 相似文献998.
Zhiqiang Li Tianyong Hou Fei Luo Zhengqi Chang Xuehui Wu Junchao Xing Moyuan Deng Jianzhong Xu 《International orthopaedics》2014,38(11):2391-2398
Purpose
This study focuses on nanoscale self–assembly peptides (SAP) modified demineralized bone matrix (DBM) which provided a more effective osteogenesis and regeneration for critically-sized femur defects in goats using the selective cell retention (SCR) strategy.Methods
RADA16–I peptide was used to modify DBM and formed a composite scaffold (SAP/DBM). The morphological change and dynamic expression of osteogenic genes of mesenchymal stem cells (MSCs) derived from marrow in SAP/DBM was observed. The cells and factors in bone marrow were enriched into SAP/DBM by technology of selective cells retension (SCR). The construct was transplanted into 20-mm femur defects in goats and their osteogenesis was evaluated.Results
The SAP/DBM scaffold formed a three-dimensional interweaving nanofiber in pores of DBM. MSCs exhibited better morphology in SAP/DBM than that in only DBM, and the levels of expression of ALP ,OCN and Runx2 gene in SAP/DBM samples was significantly higher than that of DBM at 14 days in vitro (P?0.05). Compared with marrow-enriched DBM, the volume of newly formed bone from marrow-enriched SAP/DBM is higher in goats (P?0.05).Conclusion
Our study may not only have a significant impact on the construction method of tissue engineering but also provide a viable, simple and effective method for clinical bone construction. 相似文献999.
Nan Xia Xiao Y. Wu Xing Wang Zong X. Mou Man Q. Wang Xin Gu Xiao L. Zheng Wen S. Hou 《Lasers in medical science》2014,29(1):343-349
Pulsed near-infrared radiation has been proposed as an alternative stimulus for auditory nerve stimulation and could be potentially used in the design of cochlear implant. Although the infrared with high absorption coefficient of water (i.e., wavelength ranged from 1.8 to 2.2 μm) has been widely investigated, the lymph in the cochlea absorbs most of the infrared energies, and only a small part can arrive at the target auditory nerves. The present study is aimed to test whether the short-wavelength near-infrared irradiation with lower absorption coefficients can penetrate the lymph fluid to stimulate the auditory nerves. An 808-nm near-infrared laser was chosen to stimulate the auditory nerve in the guinea pig cochlea. The infrared pulse was delivered by an optical fiber that was surgically inserted near the round window membrane and oriented toward the spiral ganglion cells in the basal turn of the cochlea. The 2-Hz infrared pulses were used to stimulate the cochlea before and after the deafness with different pulse durations (100–1,000 μs). Optically evoked compound action potentials (oCAPs) were recorded during the infrared radiation. We successfully recorded oCAPs from both normal hearing animals and deafened animals. The oCAP amplitude increased with the infrared radiation energy. The preliminary experiment suggests that the near-infrared with lower absorption coefficients can effectively pass through the lymph filled in the cochlea and stimulate the auditory nerve. Further studies will optimize the deafness animal model and determine the optimal stimulation parameters. 相似文献
1000.
Hong Qi Zhang Jia Huang Chao Feng Guo Shao Hua Liu Ming Xing Tang 《European spine journal》2014,23(1):234-241