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康柏西普联合EX-PRESS青光眼引流器植入对NVG患者视力及并发症的影响 被引量:7
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作者 赵媛 余敏 +3 位作者 代艳 张然 李建全 唐云户 《国际眼科杂志》 CAS 北大核心 2020年第10期1809-1813,共5页
目的:探讨玻璃体腔注射康柏西普联合EX-PRESS青光眼引流器植入对新生血管性青光眼(NVG)患者视力及并发症的影响。方法:选取2016-02/2018-10我院眼科收治的NVG患者128例,依据患者的治疗方法分为EX-PRESS组(n=66)和小梁切除术组(n=62),两... 目的:探讨玻璃体腔注射康柏西普联合EX-PRESS青光眼引流器植入对新生血管性青光眼(NVG)患者视力及并发症的影响。方法:选取2016-02/2018-10我院眼科收治的NVG患者128例,依据患者的治疗方法分为EX-PRESS组(n=66)和小梁切除术组(n=62),两组患者接受玻璃体腔注射康柏西普治疗,EX-PRESS组患者加行EX-PRESS青光眼引流器植入术治疗,小梁切除术组患者则加行小梁切除术治疗。比较两组手术疗效及术后眼压变化、视力改善情况及并发症发生情况。结果:术后12mo时,EX-PRESS组、小梁切除术组手术治疗总成功率分别为81.8%(54/66)、72.6%(45/62)(P>0.05);术后1、7d,1、3、6、12mo,两组患者眼压均显著低于术前(P<0.05),但两组患者眼压无差异(P>0.05);术后6mo,EX-PRESS组患者视力改善情况显著优于小梁切除术组患者(P<0.05);EX-PRESS组、小梁切除术组术后并发症总发生率分别为27.3%(18/66)、37.1%(23/62)(P>0.05)。结论:玻璃体腔注射康柏西普联合EX-PRESS青光眼引流器植入术与联合小梁切除术治疗NVG的有效性、安全性相似,而前者在改善视力方面更具优势。 展开更多
关键词 新生血管性青光眼 康柏西普 EX-PRESS青光眼引流器 视力 并发症
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后囊膜切开在糖尿病视网膜病变硅油取出联合白内障术中的应用 被引量:4
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作者 李倩 吴延 +3 位作者 代艳 曾健 张然 邓铂林 《国际眼科杂志》 CAS 北大核心 2022年第5期849-852,共4页
目的:探讨后囊膜切开在糖尿病视网膜病变硅油取出联合白内障术中的临床疗效。方法:收集我院2019-01/2020-02诊治的糖尿病视网膜病变硅油填充眼合并白内障患者83例83眼的临床资料进行回顾性分析。根据手术方式不同分为试验组(硅油取出同... 目的:探讨后囊膜切开在糖尿病视网膜病变硅油取出联合白内障术中的临床疗效。方法:收集我院2019-01/2020-02诊治的糖尿病视网膜病变硅油填充眼合并白内障患者83例83眼的临床资料进行回顾性分析。根据手术方式不同分为试验组(硅油取出同期行后囊膜切开联合白内障手术)41眼,对照组(硅油取出联合白内障手术)42眼。术后6mo对两组的最佳矫正视力、后发性白内障的发生、眼前黑影飘动等项目进行评估,以证实后囊膜切开在糖尿病视网膜病变硅油取出联合白内障手术中的优势。结果:术后6mo,最佳矫正视力试验组优于对照组(P<0.05);后发性白内障的发生、眼前黑影飘动试验组低于对照组(P<0.05);两组眼压、术后视网膜脱离、玻璃体积血、人工晶状体偏位比较均无差异(P>0.05)。结论:后囊膜切开在糖尿病视网膜病变硅油取出联合白内障手术中的应用安全可靠,可有效地避免后发性白内障的发生。 展开更多
关键词 后囊膜切开 糖尿病视网膜病变 硅油取出 白内障
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Improved Corrosion Resistance in AZ61 Magnesium Alloys Induced by Impurity Reduction 被引量:7
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作者 yan dai Xian-Hua Chen +6 位作者 Tao yan Ai-Tao Tang Di Zhao Zhu Luo Chun-Quan Liu Ren-Ju Cheng Fu-Sheng Pan 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2020年第2期225-232,共8页
The effect of impurity element Fe on corrosion behavior of AZ61 magnesium alloys in various states has been investigated by immersion test and hydrogen evolution measurements in 3.5% sodium chloride solution.The corro... The effect of impurity element Fe on corrosion behavior of AZ61 magnesium alloys in various states has been investigated by immersion test and hydrogen evolution measurements in 3.5% sodium chloride solution.The corrosion rate is found to relay on the impurity Fe concentration in the alloys and decreases with decreasing Fe content.When Fe content drops from 150 ppm to 10 ppm,the corresponding corrosion rates under as-cast and solution treatment conditions are reduced from 8.54 mm/a and 8.61 mm/a to 2.54 mm/a and 0.21 mm/a,respectively.The corrosion pattern of the AZ61 alloys is the localized corrosion,and the galvanic couples are formed among the impurity particles,second-phase particles and the matrix.The Fe impurity particles tend to act as main cathodic to form micro-galvanic cell with the α-Mg matrix,which is harmful for corrosion resistance of AZ61 alloy. 展开更多
关键词 AZ61 MAGNESIUM ALLOY IMPURITY Fe Corrosion RATE
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乡村教育助推共同富裕的理论阐释与实践进路 被引量:8
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作者 戴妍 刘斯琪 《教育与经济》 CSSCI 北大核心 2023年第2期9-19,共11页
共同富裕是社会主义的本质要求,是中国式现代化的重要特征。实现共同富裕的关键在农村,只有农村富强、农民富足才能达成全体人民共同富裕。乡村教育是助推共同富裕的重要抓手。乡村教育能够促进乡村经济高质量发展、巩固乡村脱贫攻坚成... 共同富裕是社会主义的本质要求,是中国式现代化的重要特征。实现共同富裕的关键在农村,只有农村富强、农民富足才能达成全体人民共同富裕。乡村教育是助推共同富裕的重要抓手。乡村教育能够促进乡村经济高质量发展、巩固乡村脱贫攻坚成果、切实保障与改善村居民生、助推乡村精神文明建设,进而缓解乡村收入贫困、纾解权利贫困、消解能力贫困、破除精神贫困,为实现共同富裕扫清障碍。在乡村教育助推共同富裕的实践中,应以理念引导力、制度供给力、人才驱动力和技术创新力等为着力点,通过统筹乡村教育发展规划、优化乡村教育文化环境、完善乡村教育保障机制、扶持乡村教育人才培养、推动乡村教育数字转型等路径,构筑共同富裕全新格局、满足共同富裕精神追求、夯实共同富裕制度基础、激发共同富裕内生动力、助力共同富裕提质增效,为实现共同富裕提供永续动力。 展开更多
关键词 乡村教育 中国式现代化 共同富裕 高质量发展
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教育强国建设的中国逻辑、核心要义与实践路径 被引量:6
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作者 戴妍 黄佳攀 《教育与经济》 CSSCI 北大核心 2024年第2期13-21,共9页
教育强国是社会主义现代化强国的重要组成部分。扎实推动教育强国建设,到2035年建成教育强国,继续朝着第二个百年奋斗目标奋勇前进,是实现中华民族伟大复兴的必然要求。教育强国建设是担当民族复兴教育历史使命的时代之变,观照内外形势... 教育强国是社会主义现代化强国的重要组成部分。扎实推动教育强国建设,到2035年建成教育强国,继续朝着第二个百年奋斗目标奋勇前进,是实现中华民族伟大复兴的必然要求。教育强国建设是担当民族复兴教育历史使命的时代之变,观照内外形势教育现实境遇的顺势之为,锚定人民满意教育理论旨趣的应有之义,推进中国特色教育实践创新领跑之路,全面体现了历史逻辑、现实逻辑、理论逻辑与实践逻辑的高度统一。教育强国建设由递进式核心要义构成,依次是以强条件为重要支点,以强自身为本体蕴含,以强支撑为功能延伸,以强认同为责任担当。在新的历史发展阶段,直面世界风云激荡,扎根中国现实情境,前瞻未来时空变幻,加强高素质教师队伍建设,创新推动教育数字化转型,加快建设高质量教育体系,构筑教育科技人才聚合地,助推构建全球教育共同体,已成为扎实推动教育强国建设的重要实践着力点。 展开更多
关键词 教育强国 教育现代化 中国式现代化 高质量发展
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Effect of Alloying Element on Electromagnetic Interference Shielding Effectiveness of Binary Magnesium Alloys 被引量:3
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作者 Zhu Luo Xian-Hua Chen +4 位作者 Kai Song Chun-Quan Liu yan dai Di Zhao Fu-Sheng Pan 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2019年第7期817-824,共8页
The microstructure,electrical conductivity and electromagnetic interference shielding effectiveness of Mg-X(X=Al,Sn,Y and Gd)alloys in as-cast and solution states were systematically investigated in this study.The ele... The microstructure,electrical conductivity and electromagnetic interference shielding effectiveness of Mg-X(X=Al,Sn,Y and Gd)alloys in as-cast and solution states were systematically investigated in this study.The electrical conductivity and electromagnetic shielding capacity of binary magnesium alloys decrease linearly with alloying element content.The electromagnetic shielding effectiveness of the binary magnesium alloys with the same alloying element content is as follows:Mg-Gd<Mg-Sn<Mg-Y<Mg-Al.The main reason for the differences in electromagnetic interference shielding of the binary magnesium alloys is the change in conductivity,which is mainly affected by volumetric difference of solute atoms and magnesium atoms,solute atomic valence and configuration of extranuclear electron. 展开更多
关键词 BINARY MAGNESIUM alloys Electrical CONDUCTIVITY Electromagnetic SHIELDING effectiveness ALLOYING element
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A new long-side-chain sulfonated poly(2,6-dimethyl-1,4-phenylene oxide)(PPO)/polybenzimidazole(PBI)amphoteric membrane for vanadium redox flow battery 被引量:3
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作者 Bowen Jiang Lei Hu +5 位作者 Xiaoming yan Jiahui Sun Li Gao yan dai Xuehua Ruan Gaohong He 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第7期1918-1924,共7页
A new amphoteric membrane was prepared by blending long-side-chain sulfonated poly(2,6-dimethyl-1,4-phenylene oxide)(S-L-PPO)and polybenzimidazole(PBI)for vanadium redox flow battery(VRFB)application.An acid-base pair... A new amphoteric membrane was prepared by blending long-side-chain sulfonated poly(2,6-dimethyl-1,4-phenylene oxide)(S-L-PPO)and polybenzimidazole(PBI)for vanadium redox flow battery(VRFB)application.An acid-base pair structure formed between the imidazole of PBI and sulfonic acid of S-L-PPO resulted in lowered swelling ratio.It favors to reduce the vanadium permeation.While,the increased sulfonic acid concentration ensured that proton conductivity was still at a high level.As a result,a better balance between the vanadium ion permeation(6.1×10^-9 cm^2·s^-1)and proton conductivity(50.8 m S·cm^-1)in the S-L-PPO/PBI-10%membrane was achieved.The VRFB performance with S-L-PPO/PBI-10%membrane exhibited an EE of 82.7%,which was higher than those of pristine S-L-PPO(81.8%)and Nafion 212(78.0%)at 120 m A·cm^-2.In addition,the S-LPPO/PBI-10%membrane had a much longer self-discharge duration time(142 h)than that of Nafion 212(23 h). 展开更多
关键词 Amphoteric membrane Poly(2 6-dimethyl-1 4-phenylene oxide)(PPO) Vanadium redox flow battery Polybenzimidazole(PBI) Long side chain
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Enzymatic hydrolysis of silkworm pupa and its allergenicity evaluation by animal model with different immunization routes 被引量:3
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作者 yan dai Meijia Huang +7 位作者 Yujuan Xu Lixia Mu Jingyan Gao Hongbing Chen Zhihua Wu Anshu yang Yong Wu Xin Li 《Food Science and Human Wellness》 SCIE CSCD 2023年第3期774-782,共9页
Silkworm pupa is a nourishing food with high nutritional value,but its consumption has been greatly limited given its allergenicity.Enzyme hydrolytic technique is recognized as an effective method to reduce the allerg... Silkworm pupa is a nourishing food with high nutritional value,but its consumption has been greatly limited given its allergenicity.Enzyme hydrolytic technique is recognized as an effective method to reduce the allergenicity of protein.In this study,we aimed to investigate the effect of enzymolysis on the allergenicity of silkworm pupa.Crude silkworm pupa protein was extracted through alkali extraction and acid precipitation,which included 5 proteins with the molecular weights ranging from 34 kDa to 76 kDa,and silkworm pupa were then hydrolyzed by alkaline protease.The allergenicity of silkworm pupa protein and its enzymatic hydrolysates was evaluated by establishing BALB/c mice model,and the mice were immunized via intragastric gavage and intraperitoneal injection,respectively.The results indicated that the intraperitoneal inj ection immunization route induced more by detecting with antibodies,histamine and Th2-related cytokines.Moreover,mice treated with silkworm pupa protein peptide displayed no obvious allergic symptoms,indicating that enzyme hydrolytic technique could significantly reduce the allergenicity of silkworm pupa. 展开更多
关键词 Silkworm pupa Silkworm pupa peptides Enzymatic hydrolysis ALLERGENICITY IMMUNIZATION Animal model
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Heart rate-adjusted PR as a prognostic marker of long-term ventricular arrhythmias and cardiac death in ICD/CRT-D recipients 被引量:2
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作者 Yu-Qiu LI Shuang ZHAO +8 位作者 Ke-Ping CHEN yang-Gang SU Wei HUA Si-Lin CHEN Zhao-Guang LIANG Wei XU yan dai Xiao-Han FAN Shu ZHANG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2019年第3期259-264,共6页
Objective To evaluate the PR to RR interval ratio (PR/RR,heart rate-adjusted PR) as a prognostic marker for long-term ventricular arrhythmias and cardiac death in patients with implantable cardioverter defibrillator (... Objective To evaluate the PR to RR interval ratio (PR/RR,heart rate-adjusted PR) as a prognostic marker for long-term ventricular arrhythmias and cardiac death in patients with implantable cardioverter defibrillator (ICDs) and cardiac resynchronization therapy with defibrillators (CRT-D).Methods We retrospectively analyzed data from 428 patients who had an ICD/CRT-D equipped with home monitoring.Baseline PR and RR interval data prior to ICD/CRT-D implantation were collected from standard 12-lead electrocardiograph,and the PR/RR was calculated.The primary endpoint was appropriate ICD/CRT-D treatment of ventricular arrhythmias (VAs),and the secondary endpoint was cardiac death.Results During a mean follow-up period of 38.8 ± 10.6 months,197 patients (46%) experienced VAs,and 47 patients (11%) experienced cardiac death.The overall PR interval was 160 ± 40 ms,and the RR interval was 866 ± 124 ms.Based on the receiver operating characteristic curve,a cut-off value of 18.5% for the PR/RR was identified to predict VAs.A PR/RR ≥ 18.5% was associated with an increased risk of VAs [hazard ratio (HR)= 2.243,95% confidence interval (CI)= 1.665–3.022,P < 0.001) and cardiac death (HR = 2.358,95%CI = 1.240–4.483,P = 0.009) in an unadjusted analysis.After adjustment in a multivariate Cox model,the relationship remained significant among PR/RR ≥ 18.5%,VAs (HR = 2.230,95%CI = 1.555–2.825,P < 0.001) and cardiac death (HR = 2.105,95%CI = 1.101–4.025,P = 0.024.Conclusions A PR/RR ≥ 18.5% at baseline can serve as a predictor of future VAs and cardiac death in ICD/CRT-D recipients. 展开更多
关键词 Implantable cardioverter DEFIBRILLATOR PR INTERVAL RR INTERVAL VENTRICULAR ARRHYTHMIAS
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Diabetic macular edema in proliferative stage treated with anti-vascular endothelial growth factor agent and triamcinolone acetonide by laser-based strategies 被引量:7
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作者 Gang Qiao Wan-Jiang Dong +2 位作者 yan dai Zhen-Hua Jiang Hai-Ke Guo 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第7期1113-1119,共7页
AIM: To appraise the effect of treatment for diabetic macular edema(DME) in proliferative stage with sufficient panrentinal photocoagulation(PRP) therapy and intravitreal injections(IV) Conbercept and posterior... AIM: To appraise the effect of treatment for diabetic macular edema(DME) in proliferative stage with sufficient panrentinal photocoagulation(PRP) therapy and intravitreal injections(IV) Conbercept and posterior subtenon's triamcinolone acetonide(STTA) sequential therapy.METHODS: This prospective clinical randomized controlled trial of cross-over design was conducted in three phases. The participants included cases of DME in proliferative stage. They were divided into two groups and treated with PRP before enrollment. Group A were treated with IVConbercept 0.5 mg for one month in the 1^st phase. Group B were treated with STTA 40 mg(twice per two weeks). The interventions were exchanged in the second phase(2mo) between the two groups. In the third phase(3-6mo) no other treatment was given. Best corrected visual acuity(BCVA), central macular thickness(CMT) measured by OCT and complications were compared.RESULTS: After phase I: in Group A, BCVA improved from 0.201±0.17 to 0.37±0.24(F=5.88, P=0.004). CMT changed from 449±155.10 to 304.1±84.70 μm(F=14.9, P〈0.01). In Group B, BCVA changed from 0.195±0.19 to 0.26±0.20(F=0.76, P=0.41) while CMT changed from 463.82±152.92 to 366.00±115.40 μm(F=3.70, P〈0.03). The improvement of BCVA was better in Group A(P〈0.05). After phase II: in Group A, BCVA raised to 0.47±0.27(F=0.26, P〈0.01), CMT reduced to 260.67±62.97 μm(F=-188.3, P〈0.01); in Group B, BCVA raised to 0.51±0.26(F=0.31, P〈0.01), CMT reduced to 261.93±50.15 μm(F=-201.9, P〈0.01). But there were no difference between two groups(P〉0.05). After phase III: in Group A, BCVA maintained 0.42±0.25(F=0.22, P=0.001), CMT maintained 267.8±58.34 μm,(F=-0.27, P〈0.01); in Group B, BCVA was 0.47±0.25(F=-0.27, P〈0.01), CMT was 272.71±49.16 μm(F=-191.1, P〈0.01). No serious complications happened in all phases.CONCLUSION: PRP+Conbercept is better than PRP+STTA in DME with proliferative stage but PRP+Conbercept+STTA sequential therapy may be a wiser choice for persistent effectiveness on anatomical as well as functional status. 展开更多
关键词 Conbercept sequential therapy cross-over design diabetic macular edema
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Sub-threshold micro-pulse diode laser treatment in diabetic macular edema: a Meta-analysis of randomized controlled trials 被引量:6
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作者 Gang Qiao Hai-Ke Guo +5 位作者 yan dai Xiao-Li Wang Qian-Li Meng Hui Li Xiang-Hui Chen Zhong-Lun Chen 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第7期1020-1027,共8页
AIM:To examine possible differences in clinical outcomes between sub-threshold micro-pulse diode laser photocoagulation(SDM) and traditional modified Early Treatment Diabetic Retinopathy Study(mETDRS)treatment pr... AIM:To examine possible differences in clinical outcomes between sub-threshold micro-pulse diode laser photocoagulation(SDM) and traditional modified Early Treatment Diabetic Retinopathy Study(mETDRS)treatment protocol in diabetic macuiar edema(DME).METHODS:A comprehensive literature search using the Cochrane Collaboration methodology to identify RCTs comparing SDM with mETDRS for DME.The participants were type Ⅰ or type Ⅱ diabetes mellitus with clinically significant macuiar edema treated by SDM from previously reported randomized controlled trials(RCTs).The primary outcome measures were the changes in the best corrected visual acuity(BCVA) and the central macuiar thickness(CMT) as measured by optical coherence tomography(OCT).The secondary outcomes were the contrast sensitivity and the damages of the retina.RESULTS:Seven studies were identified and analyzed for comparing SDM(215 eyes) with mETDRS(210 eyes)for DME.There were no statistical differences in the BCVA after treatment between the SDM and mETDRS based on the follow-up:3mo(MD,-0.02;95% Cl,-0.12 to 0.09;P=0.77),6mo(MD,-0.02;95% Cl,-0.12 to 0.09;P=0.75),12mo(MD,-0.05;95% Cl,-0.17 to 0.07;P=0.40).Likewise,there were no statistical differences in the CMT after treatment between the SDM and mETDRS in 3mo(MD,-9.92;95% Cl,-28.69 to 8.85;P=0.30),6mo(MD,-11.37;95% Cl,-29.65 to 6.91;P=0.22),12mo(MD,8.44;95% Cl,-29.89 to 46.77;P=0.67).Three RCTs suggested that SDM laser results in good preservation of contrast sensitivity as mETDRS,in two different followup evaluations:3mo(MD,0.05;95% Cl,0 to 0.09;P=0.04) and 6mo(MD,0.02;95% Cl,-0.10 to 0.14;P=0.78).Two RCTs showed that the SDM laser treatment did less retinal damage than that mETDRS did(OR,0.05;95% Cl,0.02 to 0.13;P〈0.01).CONCLUSION:SDM laser photocoagulation shows an equally good effect on visual acuity,contrast sensitivity,and reduction of DME as compared to conventional mETDRS protocol with less retinal damage. 展开更多
关键词 sub-threshold laser photocoagulation diabetic macular edema
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Effect of inhibiting HMGB1 gene expression on ultrasonic blood flow characteristics, inflammatory response and apoptosis in diabetic retinopathy rats 被引量:1
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作者 Yun-Feng Wei Dao-Ning Guo +2 位作者 Qiong Liu yan dai Qian Ding 《Journal of Hainan Medical University》 2020年第8期16-19,共4页
Objective:To study the effect of inhibiting high mobility group box 1(HMGB1)gene expression on ultrasonic blood flow characteristics,inflammatory response and apoptosis in diabetic retinopathy rats.Methods:Male SD rat... Objective:To study the effect of inhibiting high mobility group box 1(HMGB1)gene expression on ultrasonic blood flow characteristics,inflammatory response and apoptosis in diabetic retinopathy rats.Methods:Male SD rats were chosen and randomly divided into control group,model group and HMGB1 inhibition group,the latter two groups were given intraperitoneal injection of streptozotocin to establish the diabetes model,and HMGB1 group were given tail vein injection of HMGB1-shRNA lentivirus for intervention.The peak end-systolic velocity(PSV),peak end-diastolic velocity(EDV),resistance index(RI)and pulsatility index(PI)of central retinal artery as well as the HMGB1,bcl-2,bax and cleaved caspase-3 expression and TNF-α,MCP-1 and ICAM-1 contents in retinal tissues were measured at 4 weeks after intervention.Results:The PSV and EDV levels as well as bcl-2 expression in the model group were lower than those in the control group,while the RI and PI levels as well as HMGB1,bax and cleaved caspase-3 expression and TNF-α,MCP-1 and ICAM-1 contents were higher than those in the control group;the PSV and EDV levels as well as bcl-2 expression in the HMGB1 inhibition group were higher than those in the model group,while the RI and PI levels as well as HMGB1,bax and cleaved caspase-3 expression and TNF-α,MCP-1 and ICAM-1 contents were lower than those in the model group.Conclusion:Inhibition of HMGB1 gene expression can improve the blood flow of central retinal artery and inhibit the inflammatory response and apoptosis in diabetic retinopathy rats. 展开更多
关键词 Diabetic retinopathy High mobility group box 1 Inflammatory response APOPTOSIS
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复杂运行环境下重载铁路机车轮对磨耗机理及影响因素研究 被引量:1
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作者 衡纬 颜岱 +2 位作者 苗磊 王若瑾 李嘉音 《中国铁路》 北大核心 2024年第12期130-139,共10页
随着重载列车运行速度及轴重不断增大,机车轮对磨耗问题日益严峻。轮对磨耗是复杂轮轨关系作用的结果,受线路条件、司机操作、列车编组及自然环境多因素的共同影响。因此,提出一种基于复杂运行系统的重载机车轮对磨耗机理及其影响因素... 随着重载列车运行速度及轴重不断增大,机车轮对磨耗问题日益严峻。轮对磨耗是复杂轮轨关系作用的结果,受线路条件、司机操作、列车编组及自然环境多因素的共同影响。因此,提出一种基于复杂运行系统的重载机车轮对磨耗机理及其影响因素研究方法。系统性分析重载机车轮对磨耗类型,并基于轮轨作用关系深入研究了车轮磨耗机理及成因;构建复杂运行环境下重载铁路机车轮-轨耦合作用动力学模型;研究复杂运行环境下机车轮对磨耗关键影响因素,并采用磨耗指标等参数进行定量分析。研究结果表明:机车运行速度、线路曲线半径、轮轨摩擦系数对轮轨磨耗指标影响显著。其中,机车运行速度与机车安全性指标和轮轨磨耗指标呈正相关,线路曲线半径与机车安全性指标和轮轨磨耗指标呈负相关,而轮轨摩擦系数与轮轨磨耗指标及机车安全性指标呈正相关。根据研究结果,提出以下重载列车运行优化建议:(1)依据线路特性动态调整列车运行速度;(2)在雨雪等恶劣气象条件下根据轮轨摩擦系数动态调整列车运行速度;(3)融合先进的复杂运行环境监测技术,用以支持重载列车运行控制,保障列车运行安全与效率的统一。 展开更多
关键词 重载铁路 轮轨接触 轮对磨耗 机车多体动力学仿真模型 轮轨磨耗指标 机车安全性指标
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球墨铸铁高速铣削加工工艺参数优化实验研究
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作者 晏岱 崔明稳 +1 位作者 江吉彬 陈丙三 《福建工程学院学报》 CAS 2018年第6期520-525,共6页
针对难加工球墨铸铁材料进行高速铣削工艺参数优化研究,设计了四因素四水平正交实验,以获得铣削用量对加工过程力和表面粗糙度的影响关系,并利用多元回归分析建立铣削分力和粗糙度的经验模型。研究结果表明:每齿进给量对粗糙度值影响最... 针对难加工球墨铸铁材料进行高速铣削工艺参数优化研究,设计了四因素四水平正交实验,以获得铣削用量对加工过程力和表面粗糙度的影响关系,并利用多元回归分析建立铣削分力和粗糙度的经验模型。研究结果表明:每齿进给量对粗糙度值影响最为显著,铣削参数设置不同,产生的铣削分力不同,背吃刀量对铣削分力影响最大。针对最小铣削力与最小粗糙度的目标,分别得出最优的铣削用量参数。 展开更多
关键词 球墨铸铁 高速铣削 正交实验 粗糙度 工艺参数优化
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A programmable CRISPR/dCas9-based epigenetic editing system enabling loci-targeted histone citrullination and precise transcription regulation
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作者 Xiaoya Zhang Abhisek Bhattacharya +4 位作者 Chunxiang Pu yan dai Jia Liu Lang Rao Chaoguang Tian 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2024年第12期1485-1493,共9页
Histone citrullination,an important post-translational modification mediated by peptidyl arginine deiminases,is essential for many physiological processes and epigenetic regulation.However,the causal relationship betw... Histone citrullination,an important post-translational modification mediated by peptidyl arginine deiminases,is essential for many physiological processes and epigenetic regulation.However,the causal relationship between histone citrullination and specific gene regulation remains unresolved.In this study,we develop a programmable epigenetic editor by fusing the peptidyl arginine deiminase(PAD)PPAD from Porphyromonas gingivalis with d Cas9.With the assistance of g RNA,PPAD-d Cas9 can recruit PPADs to specific genomic loci,enabling direct manipulation of the epigenetic landscape and regulation of gene expression.Our citrullination editor allows for the site-specific manipulation of histone H3R2,8,17 and H3R26 at target human gene loci,resulting in the activation or suppression of different genes in a locus-specific manner.Moreover,the epigenetic effects of the citrullination editor are specific and sustained.This epigenetic editor offers an accurate and efficient tool for exploring gene regulation of histone citrullination. 展开更多
关键词 HISTONE CITRULLINATION Epigenetic editor Peptidyl arginine deiminase dCas9
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Dissolution-regrowth synthesis of SiO_2 nanoplates and embedment into two carbon shells for enhanced lithium-ion storage
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作者 Zhijun yan Xiangcun Li +3 位作者 Xiaobin Jiang Le Zhang yan dai Gaohong He 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第7期1522-1527,共6页
In this work, SiO2 nanoplates with opened macroporous structure on carbon layer (C-mSiO2) have been obtained by dissolving and subsequent ingrowing the outer solid SiO2 layer of the aerosol-based C-SiO2 double-shell... In this work, SiO2 nanoplates with opened macroporous structure on carbon layer (C-mSiO2) have been obtained by dissolving and subsequent ingrowing the outer solid SiO2 layer of the aerosol-based C-SiO2 double-shell hollow spheres. Subsequently, triple-shell C-mSiO2-C hollow spheres were successfully prepared after coating the C- mSiO2 templates by the carbon layer from the carbonization of sucrose. When being applied as the anode material fur lithium-ion batteries, the C-mSiO2-C triple-shell hollow spheres deliver a high capacity of 501 mA. h.g- 1 after 100 cycles at 500 mA.g-1 (based on the total mass of silica and the two carbon shells), which is higher than those of C-mSiO2 (391 mA.h.g 1) spheres with an outer porous SiO2 layer, C-SiO2-C (370 mA-h.g-1) hollow spheres with a middle solid Si02 layer, and C-SiO2 (319.8 mA·h-g-1) spheres with an outer solid SiO2 layer. In addition, the battery still delivers a high capacity of 403 mA· h· g- 1 at a current density of 1000 mA· g- 1 after 400 cycles. The good electrochemical performance can be attributed to the high surface area (246.7 m2·g- 1 ) and pore volume (0.441 cm3· g-1) of the anode materials, as well as the unique structure of the outer and inner carbon layer which not only enhances electrical conductivity, structural stability, but buffers volume change of the intermediate SiO2 layer during repeated charge-discharge processes. Furthermore, the SiO2 nanoplates with opened macroporous structure facilitate the electrolyte transport and electrochemical reaction. 展开更多
关键词 Silica nanoplates Carbon shell MACROPOROUS Lithium-ion battery
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Comparison of electrocardiogram characteristics between left bundle branch pacing and right ventricular septal pacing in patients receiving pacemaker therapy
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作者 Yuqiu Li Keping Chen +4 位作者 yan dai Qi Sun Bin Luo Chao Li Shu Zhang 《中国循环杂志》 CSCD 北大核心 2018年第S01期155-155,共1页
Background and Objective Cardiac pacing is an effective therapy in patients with bradycardia.Conventional right ventricular(RV)pacing is the source of ventricular dyssynchrony,leading to unfavorable clinical outcome.T... Background and Objective Cardiac pacing is an effective therapy in patients with bradycardia.Conventional right ventricular(RV)pacing is the source of ventricular dyssynchrony,leading to unfavorable clinical outcome.This study compared the electrocardiogram(ECG)characteristics during left bundle branch pacing(LBBP)with that during RV septal pacing(RVSP)which has been thought to be better than RV apical pacing. 展开更多
关键词 RIGHT VENTRICULAR ELECTROCARDIOGRAM RV SEPTAL PACING
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二维板式磁流减振器的力学建模与实验分析
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作者 陈丙三 赖晓彬 +2 位作者 李春雨 晏岱 张宁 《福建师范大学学报(自然科学版)》 CAS 北大核心 2019年第2期48-55,共8页
针对工程中二维减振需求,设计了一种二维板式磁流变减振器.基Navier-Stokes方程建立了二维平面内减振器的速度和压力分布模型,以及阻尼力计算模型,从理论角度定性分析了结构物理参数工作间隙δ、中间滑板长度和宽度a对减振器的阻尼力的... 针对工程中二维减振需求,设计了一种二维板式磁流变减振器.基Navier-Stokes方程建立了二维平面内减振器的速度和压力分布模型,以及阻尼力计算模型,从理论角度定性分析了结构物理参数工作间隙δ、中间滑板长度和宽度a对减振器的阻尼力的影响,并在二维振动试验台上进行减振实验,分析励磁电流对二维板式磁流变减振器的减振性能的影响.实验表明:当选用适当的磁流变流体后,库仑阻尼力对磁流变减振器阻尼力的影响较大,随着励磁电流的增大磁流变减振器阻尼力变大,系统在两个方向上的振幅均逐渐减少,最大减幅为2. 595 6倍,证实了二维板式磁流变减振器的结构设计是合理的. 展开更多
关键词 磁流变液 二维板式磁流变减振器 力学建模 减振实验
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Intra-day variability of BL Lacertae from 2016 to 2018
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作者 Tian Li Jiang-Hua Wu +2 位作者 Nan-Kun Meng yan dai Xiao-Yuan Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第10期187-196,共10页
We monitored BL Lacertae in the B,V,R and I bands for 14 nights during the period of 2016-2018.The source showed significant intra-day variability on 12 nights.We performed color-magnitude analysis and found that the ... We monitored BL Lacertae in the B,V,R and I bands for 14 nights during the period of 2016-2018.The source showed significant intra-day variability on 12 nights.We performed color-magnitude analysis and found that the source exhibited bluer-when-brighter chromatism.This bluer-when-brighter behavior is at least partly caused by the larger variation amplitude at shorter wavelengths.The variations at different wavelengths are correlated well and show no inter-band time lag. 展开更多
关键词 galaxies:active BL Lacertae objects:individual:BL Lacertae galaxies:photometry
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Association of time-varying changes in physical activity with cardiac death and all-cause mortality after ICD or CRT-D implantation
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作者 Xue-Rong SUN Chen-Di CHENG +10 位作者 Bin ZHOU Shuang ZHAO Ke-Ping CHEN Wei HUA yan-Gang SU Wei XU Fang WANG Xiao-Han FAN yan dai Zhi-Min LIU Shu ZHANG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2022年第3期177-188,共12页
OBJECTIVE To evaluate the association of longitudinal changes in physical activity(PA)with long-term outcomes after im-plantable cardioverter-defibrillator(ICD)or cardiac resynchronization therapy defibrillator(CRT-D)... OBJECTIVE To evaluate the association of longitudinal changes in physical activity(PA)with long-term outcomes after im-plantable cardioverter-defibrillator(ICD)or cardiac resynchronization therapy defibrillator(CRT-D)implantation.METHODS Patients with ICD/CRT-D implantation from SUMMIT registry were retrospectively analyzed.Accelerometer-de-rived PA changes over 12 months post implantation were obtained from the archived home monitoring data.The primary end-points were cardiac death and all-cause mortality.The secondary endpoints were the first ventricular arrthymia(VA)and first ap-propriate ICD shock.RESULTS In 705 patients,446(63.3%)patients showed improved PA over 12 months after implantation.During a mean 61.5-month follow-up duration,99 cardiac deaths(14.0%)and 153 all-cause deaths(21.7%)occurred.Compared to reduced/un-changed PA,improved PA over 12 months could result in significantly reduced risks of cardiac death(improved PA≤30 min:hazard ratio(HR)=0.494,95%CI:0.288−0.848;>30 min:HR=0.390,95%CI:0.235−0.648)and all-cause mortality(improved PA≤30 min:HR=0.467,95%CI:0.299−0.728;>30 min:HR=0.451,95%CI:0.304−0.669).No differences in the VAs or ICD shocks were observed across different groups of PA changes.PA changes can predict the risks of cardiac death only in the low baseline PA group,but improved PA was associated with 56.7%,57.4%,and 62.3%reduced risks of all-cause mortality in the low,moderate,and high baseline PA groups,respectively,than reduced/unchanged PA.CONCLUSIONS Improved PA could protect aganist cardiac death and all-cause mortality,probably reflecting better clinical efficacy after ICD/CRT-D implantation.Low-intensity exercise training might be encouraged among patients with different baseline PA levels. 展开更多
关键词 CARDIAC MORTALITY IMPLANTATION
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