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991.
992.
目的:探讨增殖性糖尿病视网膜病( proliferative diabetic retinopathy,PDR)患者外周血CD4+CD25+T细胞及相关基因FOXP3表达变化意义,观察其在PDR发病中的临床意义。
方法:采用流式细胞术检测PDR患者及正常对照外周血CD4+CD25+T细胞比例,Q-PCR测PDR患者、糖尿病和正常人中 FOXP3, IL-17和CTLA-4的 mRNA 表达,并用Wilcoxon秩和检验和直线相关分析法分析PDR患者糖化血红蛋白、年龄、血脂、肾功能的临床资料及它们之间相关度。
结果:PDR患者CD4+T细胞降低,CD4+CD25+T无显著差异,FOXP3和CTLA-4在PDR中下降, IL-17增高。 CD4+T细胞与年龄相关,CD4+CD25+T与患者的血肌酐存在正相关性,CD4+CD25+T细胞水平与年龄、糖化血红蛋白、血脂、血肌酐( Cr)、尿素氮( BUN)均无明显相关性。 PDR患者糖化血红蛋白、甘油三酯、总胆固醇、低密度脂蛋白均高于正常值。
结论:CD4+CD25+T细胞可能参与PDR的发病机制,并且血脂异常提示PDR可能与血脂相关。 相似文献
方法:采用流式细胞术检测PDR患者及正常对照外周血CD4+CD25+T细胞比例,Q-PCR测PDR患者、糖尿病和正常人中 FOXP3, IL-17和CTLA-4的 mRNA 表达,并用Wilcoxon秩和检验和直线相关分析法分析PDR患者糖化血红蛋白、年龄、血脂、肾功能的临床资料及它们之间相关度。
结果:PDR患者CD4+T细胞降低,CD4+CD25+T无显著差异,FOXP3和CTLA-4在PDR中下降, IL-17增高。 CD4+T细胞与年龄相关,CD4+CD25+T与患者的血肌酐存在正相关性,CD4+CD25+T细胞水平与年龄、糖化血红蛋白、血脂、血肌酐( Cr)、尿素氮( BUN)均无明显相关性。 PDR患者糖化血红蛋白、甘油三酯、总胆固醇、低密度脂蛋白均高于正常值。
结论:CD4+CD25+T细胞可能参与PDR的发病机制,并且血脂异常提示PDR可能与血脂相关。 相似文献
993.
目的:探讨舌状截囊方法在过熟期白内障囊外摘除联合人工晶状体植入术的临床效果。
方法:对380 眼过熟期白内障囊外摘除联合人工晶状体植入术中采用舌状截囊方法,术后观察及随访其疗效。
结果:所有患眼术后视力均有不同程度提高, 视力恢复情况:术后1d,0.1以下85眼(22.4%),0.1~0.3者162眼(42.6%),0.4~0.6者87眼(22.9%),0.6以上者46眼(12.1%)。术后1mo 0.1以下33眼(8.7%),0.1~0.3者152眼(40.0%),0.4~0.6者117眼(30.8%),0.6以上者78眼(20.5%)。术中术后并发症:术中悬韧带断离16眼(4.2%),后囊膜破裂25眼(6.6%), 角膜水肿53眼(13.9%),人工晶状体偏位12眼(3.2%)。
结论:舌状截囊方法容易掌握,手术的安全性更好,更适合在援非过熟期白内障囊外摘除联合人工晶状体植入术中的应用。 相似文献
994.
To improve the cycling stability and dynamic properties of layered oxide cathodes for sodium-ion batteries, surface modified P2–Na0.67Co0.25Mn0.75O2 with different levels of CeO2 was successfully synthesized by the solid-state method. X-ray photoelectron spectra, X-ray diffraction and Raman spectra show that the P2-structure and the oxidation state of cobalt and manganese of the pristine oxide are not affected by CeO2 surface modification, and a small amount of Ce4+ ions have been reduced to Ce3+ ions, and a few Ce ions have entered the crystal lattice of the P2-oxide surface during modification with CeO2. In a voltage range of 2.0–4.0 V at a current density of 20 mA g−1, 2.00 wt% CeO2-modified Na0.67Co0.25Mn0.75O2 delivers a maximum discharge capacity of 135.93 mA h g−1, and the capacity retentions are 91.96% and 83.38% after 50 and 100 cycles, respectively. However, the pristine oxide presents a low discharge capacity of 116.14 mA h g−1, and very low retentions of 39.83% and 25.96% after 50 and 100 cycles, respectively. It is suggested that the CeO2 modification enhances not only the maximum discharge capacity, but also the electric conductivity and the sodium ion diffusivity, resulting in a significant enhancement of the cycling stability and the kinetic characteristics of the P2-type oxide cathode.The CeO2 modification significantly enhances the maximum discharge capacity and cycling stability of a P2–Na0.67Co0.25Mn0.75O2 cathode. 相似文献
995.
L Meghan Mahoney Tang Tang Kai Ji Jessica Ulrich-Schad 《JMIR Public Health and Surveillance》2015,1(1)
Background
New media changes the dissemination of public health information and misinformation. During a guest appearance on the Today Show, US Representative Michele Bachmann claimed that human papillomavirus (HPV) vaccines could cause “mental retardation”.Objective
The purpose of this study is to explore how new media influences the type of public health information users access, as well as the impact to these platforms after a major controversy. Specifically, this study aims to examine the similarities and differences in the dissemination of news articles related to the HPV vaccination between Google News and Twitter, as well as how the content of news changed after Michele Bachmann’s controversial comment.Methods
This study used a purposive sampling to draw the first 100 news articles that appeared on Google News and the first 100 articles that appeared on Twitter from August 1-October 31, 2011. Article tone, source, topics, concerns, references, publication date, and interactive features were coded. The intercoder reliability had a total agreement of .90.Results
Results indicate that 44.0% of the articles (88/200) about the HPV vaccination had a positive tone, 32.5% (65/200) maintained a neutral tone, while 23.5% (47/200) presented a negative tone. Protection against diseases 82.0% (164/200), vaccine eligibility for females 75.5% (151/200), and side effects 59.0% (118/200) were the top three topics covered by these articles. Google News and Twitter articles significantly differed in article tone, source, topics, concerns covered, types of sources referenced in the article, and uses of interactive features. Most notably, topic focus changed from public health information towards political conversation after Bachmann’s comment. Before the comment, the HPV vaccine news talked more often about vaccine dosing (P<.001), duration (P=.005), vaccine eligibility for females (P=.03), and protection against diseases (P=.04) than did the later pieces. After the controversy, the news topic shifted towards politics (P=.01) and talked more about HPV vaccine eligibility for males (P=.01).Conclusions
This longitudinal infodemiology study suggests that new media influences public health communication, knowledge transaction, and poses potential problems in the amount of misinformation disseminated during public health campaigns. In addition, the study calls for more research to adopt an infodemiology approach to explore relationships between online information supply and public health decisions. 相似文献996.
997.
998.
Molecular mechanisms of human thyrocyte dysfunction induced by low concentrations of polychlorinated biphenyl 118 through the Akt/FoxO3a/NIS pathway 下载免费PDF全文
Hongwei Guo Hui Yang Huanhuan Chen Wen Li Jinmei Tang Pei Cheng Yuchun Xie Yun Liu Guoxian Ding Dai Cui Xuqin Zheng Yu Duan 《Journal of applied toxicology : JAT》2015,35(9):992-998
Polychlorinated biphenyls (PCBs) are typical persistent organic pollutants that can interfere with multiple organ systems of humans. Previously, we concluded that persistent exposure to low doses of PCB118 could severely damage the thyroidal structure, dramatically decrease the concentration of serum thyroid hormones and inhibit the pivotal gene expressions such as sodium/iodide symporter (NIS) and thyroglobulin (Tg). To explore the molecular mechanisms of thyrocyte dysfunction induced by 2,3′,4,4′,5‐pentachlorobiphenyl (PCB118), monolayer cultured human thyroid epithelial cells (HTECs) were treated with PCB118 or dimethyl sulfoxide (DMSO) as a control. Our results indicated that relatively higher concentrations of PCB118 could induce a loss in the viability of HTEC. In cultures with concentrations of PCB118 from 0.025 to 25 nM, which did not affect cell viability or apoptosis, concentrations of Tg and thyroxine (T4) were significantly decreased compared with those in the controls. In addition, mRNA and protein levels of Akt were increased significantly in the PCB118‐treated groups, whereas FoxO3a expression did not show particular variation. Furthermore, exposure to PCB118 was associated with a significant increase of the protein levels of p‐Akt and p‐FoxO3a, and these effects were blocked by LY294002. In contrast, mRNA and protein expression levels of NIS were decreased significantly, and this effect was blocked by LY294002. Unlike control cells, a cytoplasmic shift of FoxO3a was observed in the PCB118‐treated group. Our research suggests that PCB118 may induce thyrocyte dysfunction through the Akt/FoxO3a/NIS signalling pathway, which provides potential new insights for finding interventions to counteract the damage to the human body caused by PCBs. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
999.
Biological effect of food additive titanium dioxide nanoparticles on intestine: an in vitro study 下载免费PDF全文
Zheng‐Mei Song Ni Chen Jia‐Hui Liu Huan Tang Xiaoyong Deng Wen‐Song Xi Kai Han Aoneng Cao Yuanfang Liu Haifang Wang 《Journal of applied toxicology : JAT》2015,35(10):1169-1178
Titanium dioxide nanoparticles (TiO2 NPs) are widely found in food‐related consumer products. Understanding the effect of TiO2 NPs on the intestinal barrier and absorption is essential and vital for the safety assessment of orally administrated TiO2 NPs. In this study, the cytotoxicity and translocation of two native TiO2 NPs, and these two TiO2 NPs pretreated with the digestion simulation fluid or bovine serum albumin were investigated in undifferentiated Caco‐2 cells, differentiated Caco‐2 cells and Caco‐2 monolayer. TiO2 NPs with a concentration less than 200 µg ml–1 did not induce any toxicity in differentiated cells and Caco‐2 monolayer after 24 h exposure. However, TiO2 NPs pretreated with digestion simulation fluids at 200 µg ml–1 inhibited the growth of undifferentiated Caco‐2 cells. Undifferentiated Caco‐2 cells swallowed native TiO2 NPs easily, but not pretreated NPs, implying the protein coating on NPs impeded the cellular uptake. Compared with undifferentiated cells, differentiated ones possessed much lower uptake ability of these TiO2 NPs. Similarly, the traverse of TiO2 NPs through the Caco‐2 monolayer was also negligible. Therefore, we infer the possibility of TiO2 NPs traversing through the intestine of animal or human after oral intake is quite low. This study provides valuable information for the risk assessment of TiO2 NPs in food. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
1000.
Randomised clinical trial: deep remission in biologic and immunomodulator naïve patients with Crohn's disease – a SONIC post hoc analysis 下载免费PDF全文