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银杏素调节TGF⁃β1/Smad通路对ox⁃LDL诱导血管内皮细胞损伤的影响
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作者 李贺 曹慧 冯莉莉 《解剖学研究》 CAS 2024年第1期19-24,39,共7页
目的探讨银杏素调节转化生长因子⁃β1(TGF⁃β1)/Smad信号通路对ox⁃LDL诱导血管内皮细胞损伤的影响。方法将人脐静脉血管内皮细胞HUVEC分为对照组(未处理的HUVEC细胞)、模型组(50μg/mL ox⁃LDL处理的HUVEC细胞)、银杏素组(50μg/mL ox⁃LD... 目的探讨银杏素调节转化生长因子⁃β1(TGF⁃β1)/Smad信号通路对ox⁃LDL诱导血管内皮细胞损伤的影响。方法将人脐静脉血管内皮细胞HUVEC分为对照组(未处理的HUVEC细胞)、模型组(50μg/mL ox⁃LDL处理的HUVEC细胞)、银杏素组(50μg/mL ox⁃LDL+12.5μmol/L银杏素处理HUVEC细胞)、SRI⁃011381组(50μg/mL ox⁃LDL+10μmol/L的TGF⁃β1/Smad激活剂SRI⁃011381处理HUVEC细胞)、银杏素+SRI⁃011381组(50μg/mL ox⁃LDL+12.5μmol/L银杏素+10μmol/L的SRI⁃011381共同处理HUVEC细胞)。ELISA试剂盒检测HUVEC细胞丙二醛(MDA)、谷胱甘肽(GSH)、超氧化物歧化酶(SOD)、IL⁃6、IL⁃1β、TNF⁃α水平;CCK⁃8法检测HUVEC细胞增殖;流式细胞术检测HUVEC细胞凋亡率;Western blot检测细胞上皮间质转化(EMT)、TGF⁃β1/Smad通路相关蛋白表达。结果与对照组相比,模型组IL⁃1β、IL⁃6、TNF⁃α、MDA水平、细胞凋亡率、TGF⁃β1、Smad3、神经型钙黏附蛋白(N⁃cadherin)、波形蛋白(Vimentin)蛋白水平显著增加(P<0.05),A值、GSH、SOD水平、上皮钙黏附素(E⁃cadherin)蛋白水平显著降低(P<0.05);与模型组相比,银杏素组IL⁃1β、IL⁃6、TNF⁃α、MDA水平、细胞凋亡率、TGF⁃β1、Smad3、N⁃cadherin、Vimentin蛋白水平显著下降(P<0.05),A值、GSH、SOD水平、E⁃cadherin蛋白水平显著升高(P<0.05),而SRI⁃011381组趋势相反,SRI⁃011381减弱了银杏素对ox⁃LDL诱导的HUVEC细胞损伤的抑制作用。结论银杏素可能通过下调TGF⁃β1/Smad信号通路对ox⁃LDL诱导的血管内皮细胞损伤起到改善作用。 展开更多
关键词 银杏素 TGF⁃β1/Smad信号通路 氧化低密度脂蛋白 血管内皮细胞 氧化损伤
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High temperature oxidation of inoculated high Si/SiMo ductile cast irons in air and combustion atmospheres
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作者 Iuliana Stan Mihai Chisamera +5 位作者 Robert Lascu Codrut Cariga Eduard Stefan Stelian Stan Denisa Anca Iulian Riposan 《China Foundry》 SCIE EI CAS CSCD 2024年第5期555-562,共8页
The present work aims to investigate the effect of heating temperature(400,600 and 800°C)and inoculating elements(Ca,Ca-Ba,Ca-RE)on oxidation behavior of ductile irons containing 5.25%Si and 4.8%Si-2.3%Mo in dry ... The present work aims to investigate the effect of heating temperature(400,600 and 800°C)and inoculating elements(Ca,Ca-Ba,Ca-RE)on oxidation behavior of ductile irons containing 5.25%Si and 4.8%Si-2.3%Mo in dry air and combustion gas containing water vapour(natural gas burning).The oxidation is influenced by the gas atmosphere type,the iron alloying system,and the inoculating elements depending on the heating temperature.The weight gain increases from 0.001%-0.1%(400°C)to 0.05%-0.70%(600°C)and up to 0.10%-2.15%(800°C).No particular effects of the considered influencing factors are found when heating at 400°C,while at 600°C,mainly the oxidation gas atmosphere type shows a visible influence.At the highest heating temperature of 800°C,a limited increase of the weight gain is found for dry air atmosphere(up to 0.25%),but it drastically increases for combustion atmospheres(0.65%-2.15%).The water vapour presence in the combustion atmosphere is an important oxidising factor at 600-800°C.The alloying system appears to influence the oxidation behavior mainly at a heating temperature of 800°C in the combustion atmosphere,as evidenced by the lower weight gain in 5.25%silicon cast iron.Positive effects of inoculating elements increase with the heating temperature,with Ca and Ba-FeSi inoculation generally showing better performance.Irons inoculated with CaRE-FeSi exhibit a higher degree of oxidation.These results are in good relationship with the previous reported data:Ca-Ba-inoculation system appears to be better than simple Ca for improving the graphite parameters,while RE-bearing inoculant negatively affects the compactness degree of graphite particles in high-Si ductile irons.As the lower compactness degree is typical for graphite nodules in high-Si ductile irons,which negatively affects the oxidation resistance,it is necessary to employ specific metallurgical treatments to improve nodule quality.Inoculation,in particular,is a potential method to achieve this improvement. 展开更多
关键词 ductile iron spheroidal graphite Si/SiMo oxidation air/combustion atmospheres FeSiCaMgRE treatment Ca Ca-Ba Ca-RE inoculation structure characteristics
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Essen卒中风险评分联合OX-LDL、UCH-1对非房颤人群首发急性缺血性脑卒中患者短期预后的预测价值
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作者 陈小沛 刘慧 《新疆医科大学学报》 CAS 2024年第2期254-258,263,共6页
目的探讨Essen卒中风险评分联合氧化型低密度脂蛋白胆固醇(Oxidized low-density lipoprotein,OX-LDL)、血清泛素C末端水解酶L1(Ubiquitin carboxy-terminal hydrolase-L1,UCH-L1)对非房颤人群首发急性缺血性脑卒中(Acute ischemic stro... 目的探讨Essen卒中风险评分联合氧化型低密度脂蛋白胆固醇(Oxidized low-density lipoprotein,OX-LDL)、血清泛素C末端水解酶L1(Ubiquitin carboxy-terminal hydrolase-L1,UCH-L1)对非房颤人群首发急性缺血性脑卒中(Acute ischemic stroke,AIS)患者短期预后的预测价值。方法根据改良Rankin量表(Modified rankin scale,mRS)评分,将132例非房颤人群首发AIS患者分为预后良好组(mRS≤2分)93例,预后不良组(mRS>2分)39例,在入院治疗前进行Essen卒中风险评分和血清OX-LDL、UCH-L1检测。采用Spearman相关性分析Essen卒中风险评分与OX-LDL、UCH-L1水平的差异,采用Logistic回归分析预后不良的危险因素,采用受试者工作特征(Receiver operating characteristic,ROC)曲线分析Essen卒中风险评分、OX-LDL、UCH-L1水平及三者联合对非房颤人群首发AIS预后评估的效果。结果预后不良组Essen卒中风险评分高于预后良好组(Z=-5.365,P<0.001),血清中OX-LDL、UCH-L1水平高于预后良好组(Z=-6.152,P<0.001;Z=-7.020,P<0.001)。血清中OX-LDL、UCH-L1水平与Essen评分呈正相关(r=0.629,P<0.001;r=0.598,P<0.001)。Logistic回归分析显示,Essen卒中风险评分、OX-LDL、UCH-L1是脑卒中预后的独立影响因素。Essen卒中风险评分联合OX-LDL、UCH-L1对非房颤人群首发AIS预后的ROC曲线下面积为0.896,灵敏度为88.54%,特异度为92.93%。结论Essen卒中风险评分联合OX-LDL、UCH-L1对非房颤人群首发AIS预后有良好的预测作用,Essen卒中风险评分、OX-LDL、UCH-L1水平越高,提示预后不良的风险越大。 展开更多
关键词 Essen卒中风险评分量表 氧化型低密度脂蛋白胆固醇 血清泛素C末端水解酶L1 急性缺血性脑卒中
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基于PI3K/Akt/mTOR信号通路的miR-24调控ox-LDL诱导的HUVECs自噬机制研究
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作者 杨鹏 杨增艳 +3 位作者 翟阳 周炜潜 罗雪兰 欧和生 《右江医学》 2024年第9期775-783,共9页
目的探讨miR-24对氧化低密度脂蛋白(ox-LDL)诱导下的人脐静脉内皮细胞(HUVECs)自噬的影响及其相关机制,为进一步阐明miR-24在动脉粥样硬化(AS)中的作用提供理论依据。方法采用实时荧光定量PCR(qRT-PCR)检测miR-24的表达;应用蛋白免疫印... 目的探讨miR-24对氧化低密度脂蛋白(ox-LDL)诱导下的人脐静脉内皮细胞(HUVECs)自噬的影响及其相关机制,为进一步阐明miR-24在动脉粥样硬化(AS)中的作用提供理论依据。方法采用实时荧光定量PCR(qRT-PCR)检测miR-24的表达;应用蛋白免疫印迹法(western blot)和qRT-PCR法检测Beclin-1、LC3Ⅰ/LC3Ⅱ、p-mTOR、p-PI3K、p-Akt的蛋白和mRNA表达水平;应用透射电子显微镜技术检测细胞的自噬小体生成情况;应用四甲基偶氮唑盐(MTT)法、细胞划痕法、Caspase-3比色法和Hoechst 33258染色法分别检测细胞活性、迁移和凋亡情况。结果应用ox-LDL诱导HUVECs后,发现HUVECs中miR-24的表达显著降低(P<0.05)。miR-24过表达可明显抑制ox-LDL诱导的HUVECs自噬(P<0.05),而miR-24低表达则会增加ox-LDL诱导的HUVECs自噬(P<0.05)。miR-24过表达可显著降低Beclin-1的表达水平,上调LC3Ⅰ/LC3Ⅱ的水平(P<0.05),同时,miR-24过表达可显著促进p-PI3K、p-Akt和p-mTOR的表达(P<0.05)。此外,miR-24过表达显著抑制HUVECs的活力和迁移,增加Caspase-3活性并促进其凋亡(P<0.05)。结论miR-24的过表达可激活PI3K/Akt/mTOR信号通路而降低ox-LDL诱导的HUVECs的自噬水平并促进其凋亡,miR-24可能成为AS的潜在治疗新靶点。 展开更多
关键词 氧化低密度脂蛋白 人脐静脉内皮细胞 PI3K/Akt/mTOR信号通路 miR-24 自噬 凋亡
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Advances of study on atmospheric methane oxidation (consumption) in forest soil 被引量:2
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作者 王琛瑞 史奕 +2 位作者 杨晓明 吴杰 岳进 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期230-238,共9页
Next to CO2, methane (CH4) is the second important contributor to global warming in the atmosphere and global atmospheric CH4 budget depends on both CH4 sources and sinks. Unsaturated soil is known as a unique sink fo... Next to CO2, methane (CH4) is the second important contributor to global warming in the atmosphere and global atmospheric CH4 budget depends on both CH4 sources and sinks. Unsaturated soil is known as a unique sink for atmospheric CH4 in terrestrial ecosystem. Many comparison studies proved that forest soil had the biggest capacity of oxidizing atmospheric CH4 in various unsaturated soils. However, up to now, there is not an overall review in the aspect of atmospheric CH4 oxidation (consumption) in forest soil. This paper analyzed advances of studies on the mechanism of atmospheric CH4 oxidation, and re-lated natural factors (Soil physical and chemical characters, temperature and moisture, ambient main greenhouse gases con-centrations, tree species, and forest fire) and anthropogenic factors (forest clear-cutting and thinning, fertilization, exogenous aluminum salts and atmospheric deposition, adding biocides, and switch of forest land use) in forest soils. It was believed that CH4 consumption rate by forest soil was limited by diffusion and sensitive to changes in water status and temperature of soil. CH4 oxidation was also particularly sensitive to soil C/N, Ambient CO2, CH4 and N2O concentrations, tree species and forest fire. In most cases, anthropogenic disturbances will decrease atmospheric CH4 oxidation, thus resulting in the elevating of atmos-pheric CH4. Finally, the author pointed out that our knowledge of atmospheric CH4 oxidation (consumption) in forest soil was insufficient. In order to evaluate the contribution of forest soils to atmospheric CH4 oxidation and the role of forest played in the process of global environmental change, and to forecast the trends of global warming exactly, more researchers need to studies further on CH4 oxidation in various forest soils of different areas. 展开更多
关键词 atmospheric methane oxidation Global warming Forest soil SINK
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Atmospheric nitrous oxide observations above the oceanic surface during the first Chinese Arctic Research Expedition 被引量:3
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作者 朱仁斌 孙立广 +1 位作者 谢周清 赵俊琳 《Chinese Journal of Polar Science》 2003年第2期138-148,共11页
339 gas samples above oceanic surface were collected on the cruise of 'Xuelong' expeditionary ship and nitrous oxide concentrations were analyzed in the laboratory. Results showed that Atmospheric average N2O ... 339 gas samples above oceanic surface were collected on the cruise of 'Xuelong' expeditionary ship and nitrous oxide concentrations were analyzed in the laboratory. Results showed that Atmospheric average N2O concentration was 309 ±3. 8nL/L above the surface of northern Pacific and Arctic ocean. N2O concentrations were significantly different on the northbound and southbound track in the range of the same latitude, 308.0 ±3.5 nL/L from Shanghai harbor to the Arctic and 311.9 ±2.5 nL/L from the Arctic to Shanghai harbor. N2O concentration had a greater changing magnitude on the mid- and high-latitude oceanic surface of northern Pacific Ocean than in the other latitudinal ranges. The correlation between the concentrations of the compositions in the aerosol samples and atmospheric N2 O showed that continental sources had a great contribution on atmospheric N2 O concentration above the oceanic surface. Atmospheric N2O concentration significantly increased when the expeditionary ship approached Shanghai harbor. The average N2O concentrations were 315.1 ±2.5 nL/L, 307.2±1.4 nL/L and 306.2 ±0.7 nL/L, respectively, at Shanghai harbor, at ice stations and at floating ices. The distribution of N2O concentrations was related with air pressure and temperature above the mid- and high-latitude Pacific Ocean. 展开更多
关键词 Arctic Ocean Northern Pacific Ocean Nitrous oxide Atmosphere.
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A Study on Catalysis by Ferrospinels for Preventing Atmospheric Pollution from Carbon Monoxide 被引量:2
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作者 Chennampilly Ummer Aniz Thengumthanam Damodaran Radhakrishnan Nair 《Open Journal of Physical Chemistry》 2011年第3期124-130,共7页
Ferrospinel catalyst samples containing Nickel, Cobalt and Copper have been synthesized by room temperature co-precipitation route and have been found to be effective for the oxidative removal of carbon monoxide from ... Ferrospinel catalyst samples containing Nickel, Cobalt and Copper have been synthesized by room temperature co-precipitation route and have been found to be effective for the oxidative removal of carbon monoxide from automobile exhaust gases even at relatively lower temperatures (cold-start). These catalyst materials have been characterized by modern physico-chemical techniques such as XRD, TG, BET-BJH and SEM etc. Nitrogen adsorption studies shows the samples are mesoporous in nature with pore diameter of 5 - 10 nm. The catalytic efficiencies of these materials of having various compositions have been tested in a series of temperature programmed oxidation reactions involving carbon monoxide and the results discussed. 展开更多
关键词 CATALYSIS Ferrospinels MESOPOROUS atmospheric POLLUTION Carbon MONoxIDE oxIDATION
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Photooxidation of Methacrolein in Fe(III)-Oxalate Aqueous System and Its Atmospheric Implication 被引量:1
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作者 Yu WANG Jie ZHAO +3 位作者 Huihui LIU Yuan LI Wenbo DONG Yanlin WU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第7期1252-1263,共12页
Iron and oxalic acids are widely distributed in the atmosphere and easily form ferric oxalate complex(Fe(III)-Ox).The tropospheric aqueous-phase could provide a medium to enable the photo-Fenton reaction with Fe(III)-... Iron and oxalic acids are widely distributed in the atmosphere and easily form ferric oxalate complex(Fe(III)-Ox).The tropospheric aqueous-phase could provide a medium to enable the photo-Fenton reaction with Fe(III)-Ox under solar irradiation.Although the photolysis mechanisms of Fe(III)-Ox have been investigated extensively,information about the oxidation of volatile organic compounds(VOC),specifically the potential for Secondary Organic Aerosol(SOA)formation in the Fe(III)-Ox system,is lacking.In this study,a ubiquitous VOC methacrolein(MACR)is chosen as a model VOC,and the oxidation of MACR with Fe(III)-Ox is investigated under typical atmospheric water conditions.The effects of oxalate concentration,Fe(III)concentration,MACR concentration,and pH on the oxidation of MACR are studied in detail.Results show that the oxidation rate of MACR greatly accelerates in the presence of oxalate when compared with only Fe(III).The oxidation rate of MACR also accelerates with increasing concentration of oxalate.The effect of Fe(III)is found to be more complicated.The oxidation rate of MACR first increases and then decreases with increasing Fe(III)concentration.The oxidation rate of MACR increases monotonically with decreasing pH in the common atmospheric water pH range or with decreasing MACR concentration.The production of ferrous and hydrogen peroxide,pH,and aqueous absorbance are monitored throughout the reaction process.The quenching experiments verify that·OH and O_(2)^(+)are both responsible for the oxidation of MACR.MACR is found to rapidly oxidize into small organic acids with higher boiling points and oligomers with higher molecular weight,which contributes to the yield of SOA.These results suggest that Fe(III)-Ox plays an important role in atmospheric oxidation. 展开更多
关键词 Fe(III)-ox OH radical atmospheric oxidation SOA METHACROLEIN
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Atmospheric-Pressure DBD Cold Plasma for Preparation of High Active Au/P25 Catalysts for Low-Temperature CO Oxidation 被引量:3
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作者 底兰波 詹志彬 +2 位作者 张秀玲 亓滨 徐伟杰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第5期544-548,共5页
Cold plasma generated by dielectric barrier discharge (DBD) at atmospheric pressure was adopted for preparation of commercial TiO2 Degussa P25 supported Au catalysts (Au/P25- P) with the assistance of the depositi... Cold plasma generated by dielectric barrier discharge (DBD) at atmospheric pressure was adopted for preparation of commercial TiO2 Degussa P25 supported Au catalysts (Au/P25- P) with the assistance of the deposition-precipitation procedure. The influences of the plasma reduction time and calcination on the performance of the Au/P25-P catalysts were investigated. CO oxidation was performed to investigate the catalytic activity of the Au/P25 catalysts. The results show that DBD cold plasma for the fabrication of Au/P25-P catalysts is a fast process, and Au/P25-P (4 min) exhibited the highest CO oxidation activity due to the complete reduction of Au compounds and less consumption of oxygen vacancies. In order to form more oxygen vacancies active species, Au/P25-P was calcined to obtain Au/P25-PC catalysts. Interestingly, Au/P25- PC exhibited the highest activity for CO oxidation among the Au/P25 samples. The results of transmission electron microscopy (TEM) indicated that the smaller size and high distribution of Au nanoparticles are the mean reasons for a high performance of Au/P25-PC. Atmospheric- pressure DBD cold plasma was proved to be of great efficiency in preparing high performance supported Au catalysts. 展开更多
关键词 atmospheric-pressure cold plasma dielectric barrier discharge (DBD) Au TiO2 CO oxidation
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Fabrication and electrochemical performance of solid oxide fuel cell components by atmospheric and suspension plasma spray 被引量:3
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作者 夏卫生 杨云珍 +1 位作者 张海鸥 王桂兰 《中国有色金属学会会刊:英文版》 EI CSCD 2009年第6期1539-1544,共6页
The theory of functionally graded material(FGM)was applied in the fabrication process of PEN(Positive-Electrolyte-Negative),the core component of solid oxide fuel cell(SOFC).To enhance its electrochemical performance,... The theory of functionally graded material(FGM)was applied in the fabrication process of PEN(Positive-Electrolyte-Negative),the core component of solid oxide fuel cell(SOFC).To enhance its electrochemical performance,the functionally graded PEN of planar SOFC was prepared by atmospheric plasma spray(APS).The cross-sectional SEM micrograph and element energy spectrum of the resultant PEN were analyzed.Its interface resistance was also compared with that without the graded layers to investigate the electrochemical performance enhanced by the functionally graded layers.Moreover,a new process, suspension plasma spray(SPS)was applied to preparing the SOFC electrolyte.Higher densification of the coating by SPS,1.61%,is observed,which is helpful to effectively improve its electrical conductivity.The grain size of the electrolyte coating fabricated by SPS is also smaller than that by APS,which is more favourable to obtain the dense electrolyte coatings.To sum up,all mentioned above can prove that the hybrid process of APS and SPS could be a better approach to fabricate the PEN of SOFC stacks,in which APS is for porous electrodes and SPS for dense electrolyte. 展开更多
关键词 固体氧化物燃料电池 大气等离子喷涂 电化学性能 电池组件 功能梯度材料 功能梯度层 悬浮 制备
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Fabrication and performance of atmospheric plasma sprayed solid oxide fuel cells with liquid antimony anodes
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作者 Yidong Jiang Wenfei Mo +2 位作者 Tianyu Cao Yixiang Shi Ningsheng Cai 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第3期360-367,共8页
A solid oxide fuel cell(SOFC)with a liquid antimony anode(LAA)is a potential energy conversion technology for the use of impurity-containing fuels.Atmospheric plasma spraying(APS)technology has become a promising LAAS... A solid oxide fuel cell(SOFC)with a liquid antimony anode(LAA)is a potential energy conversion technology for the use of impurity-containing fuels.Atmospheric plasma spraying(APS)technology has become a promising LAASOFC preparation method because of its economy and convenience.In this paper,button SOFCs with different cathode materials and ratios of pore former were prepared by the APS method and were operated at 750C.The effect of the cathode structure on the electrochemical performance of the LAA-SOFCs was analyzed,and an optimized spraying method for LAA-SOFCs was developed.A tubular LAA-SOFC was prepared using the APS method based on the optimized spraying method,and a peak power of 2.5 W was reached.The tubular cell was also measured at a constant current of 2 A for 20 h and was fed with a sulfur-containing fuel to demonstrate its impurity resistance and electrode stability. 展开更多
关键词 Solid oxide fuel cells Liquid antimony anodes atmospheric plasma spraying Pore former
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常压法硝酸装置的优化改造
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作者 黎志敏 龚赵峰 《化工生产与技术》 CAS 2024年第1期30-32,38,I0004,共5页
以杭州龙山化工的常压法硝酸装置为例,该装置在运行中出现尾气环保达标排放困难和产品结构不合理等问题。通过采取硝酸生产工艺优化和新增尾气处理装置等改造,调整了硝酸和亚硝酸钠产品结构,可减少亚硝酸钠产量2 kt/a,同时增加硝酸(质... 以杭州龙山化工的常压法硝酸装置为例,该装置在运行中出现尾气环保达标排放困难和产品结构不合理等问题。通过采取硝酸生产工艺优化和新增尾气处理装置等改造,调整了硝酸和亚硝酸钠产品结构,可减少亚硝酸钠产量2 kt/a,同时增加硝酸(质量分数为40%)产量4 kt/a;尾气中氮氧化物质量浓度<300 mg/m^(3),解决了尾气达标排放问题。该方法可为同行业类似的常压法硝酸装置改造提供借鉴经验。 展开更多
关键词 常压法硝酸装置 氮氧化物 尾气处理 氨催化还原
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日粮中添加白藜芦醇对不同部位牛肉抗氧化性能的影响 被引量:1
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作者 崔莹 李继强 +5 位作者 罗欣 朱立贤 杨啸吟 郝剑刚 张一敏 梁荣蓉 《食品与发酵工业》 CAS CSCD 北大核心 2024年第16期68-76,共9页
为研究肉牛日粮中添加白藜芦醇对血清抗氧化性能及高氧气调包装牛肉抗氧化性能的影响,选用12头杂交牛(西门塔尔牛×鲁西黄牛),随机分为全混合日粮(对照组)和补充白藜芦醇[5 g/(头·d),白藜芦醇组]饲喂120 d。检测饲养60 d和120 ... 为研究肉牛日粮中添加白藜芦醇对血清抗氧化性能及高氧气调包装牛肉抗氧化性能的影响,选用12头杂交牛(西门塔尔牛×鲁西黄牛),随机分为全混合日粮(对照组)和补充白藜芦醇[5 g/(头·d),白藜芦醇组]饲喂120 d。检测饲养60 d和120 d时血清抗氧化能力和宰后45 min不同部位肌肉中抗氧化酶活性、mRNA和蛋白表达的差异,并分析不同部位牛肉高氧气调包装贮藏期间脂质和蛋白质氧化程度的变化。研究发现,与对照组相比,日粮中添加白藜芦醇显著增强了血清和肌肉中的抗氧化酶活性(P<0.05),增加了Nrf2及其下游靶基因的表达(P<0.05),降低了高氧气调包装牛肉在贮藏期间的脂质和蛋白质氧化程度(P<0.05)。因此,日粮中添加白藜芦醇提高了不同部位牛肉的抗氧化性能,可以作为一种有效的方法来缓解牛肉贮藏流通期间的氧化缺陷。 展开更多
关键词 白藜芦醇 牛肉 抗氧化性能 高氧气调包装 氧化
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CO优先氧化反应MnCu/Ce催化剂的制备及性能 被引量:2
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作者 武嘉欣 韩蛟 +7 位作者 李学 邢月 张财顺 刘道胜 侯晓宁 刘雅杰 张磊 高志贤 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第4期565-576,共12页
采用共浸渍法制备较低Cu含量的MnCu/Ce催化剂,通过XRD、BET、H_(2)-TPR、XPS和CO_(2)-TPD等表征手段对催化剂进行表征,考察催化剂焙烧温度对催化剂结构、性质及其在含有CO_(2)的富氢气氛下对CO优先氧化性能的影响。结果表明,MnCu/Ce催... 采用共浸渍法制备较低Cu含量的MnCu/Ce催化剂,通过XRD、BET、H_(2)-TPR、XPS和CO_(2)-TPD等表征手段对催化剂进行表征,考察催化剂焙烧温度对催化剂结构、性质及其在含有CO_(2)的富氢气氛下对CO优先氧化性能的影响。结果表明,MnCu/Ce催化剂均有Cu/Mn-O-Ce固溶体形成,其中,在焙烧温度600℃制备的催化剂中,Mn与Cu、Ce之间相互作用较强,形成较多三元氧化物固溶体,氧空位/Ce^(3+)含量高,具备良好的CO-Prox活性。此外,对反应条件的考察发现,添加不同分压Ar对催化剂的CO-Prox活性影响较小,气体空速和氧过量系数对催化剂活性影响较大,且反应原料气中CO_(2)的存在对CO-Prox反应有负面影响。氧过量系数为1.2、空速范围为20266-30400 mL/(g·h)时,CO转化率最高,达到94.7%。 展开更多
关键词 低含量铜 焙烧温度 氧化铈 CO_(2)/H_(2)气氛 反应条件
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基于Nrf2靶点及线粒体质量控制系统研究姜三七挥发油对内皮细胞损伤的保护作用 被引量:1
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作者 王羽 刘新燕 徐勤 《沈阳药科大学学报》 CAS CSCD 2024年第8期1047-1054,共8页
目的研究核因子E2相关因子2(nuclear E2-related factor 2,Nrf2)靶点及线粒体质量控制系统调控姜三七挥发油(essential oil from Stahlianthus involucratus rhizomes,EOSIR)对人脐静脉内皮细胞(human umbilical vein endothelial cells... 目的研究核因子E2相关因子2(nuclear E2-related factor 2,Nrf2)靶点及线粒体质量控制系统调控姜三七挥发油(essential oil from Stahlianthus involucratus rhizomes,EOSIR)对人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs)损伤的保护作用机制。方法用氧化低密度脂蛋白(oxidized low-density lipoprotein,ox-LDL)诱导HUVECs建立细胞损伤模型,siRNA转染沉默Nrf2因子的表达,将培养好的细胞分为对照组、模型组、EOSIR组、转染组、转染阴性对照组,利用蛋白质印迹法(Western-blot)及定量即时聚合酶链锁反应(quantitative real time polymerase chain reaction,qRT-PCR)检测Nrf2及其下游因子的蛋白及mRNA的表达;Griess法检测一氧化氮含量;酶联免疫法(enzyme-linked immunosorbent assay,ELISA)分析人内皮素(endothelin 1,ET-1)、人前列环素(prostacyclin,PGI2)的含量;线粒体质量检测实验中将细胞分为空白组、ox-LDL诱导组、低剂量EOSIR组、中剂量EOSIR组、高剂量EOSIR组、阿司匹林阳性对照组,透射电镜观察HUVECs线粒体形态;Western-blot检测线粒体融合蛋白1(mitofusin 1,Mfn1)、线粒体融合蛋白2(mitofusin 1,Mfn2)、线粒体动力相关蛋白(dynamin-related protein 1,Drp1)、线粒体内膜融合蛋白(optic atrophy 1,Opa1)、线粒体转录因子A(mitochondrial transcription factor A,TFAM)、过氧化物酶体增殖物激活受体γ辅激活因子1α(peroxisome proliferatoractivated receptorγcoactivator-1α,PGC-1α)及轻链3A/B蛋白(LC3A/B)、泛素结合蛋白(p62)表达。结果EOSIR组的Nrf2及其下游因子的表达水平、NO、PGI2的含量较模型组均显著升高,ET-1水平较模型组相比显著降低,转染沉默Nrf2后,EOSIR对上述指标的改善作用被抑制;透射电镜观察线粒体形态,EOSIR干预组自噬小体数量较模型组明显减少,线粒体形态恢复正常,同时,EOSIR组显著改善了ox-LDL引起的线粒体相关蛋白表达的变化(P<0.05)。结论EOSIR可能通过激活Nrf2靶点及调控线粒体质量控制系统发挥对ox-LDL诱导的内皮细胞损伤的保护作用,延缓动脉粥样硬化的进程。 展开更多
关键词 动脉粥样硬化 氧化应激 氧化低密度脂蛋白 Nrf2信号通路 线粒体
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Ox-LDL诱导血管内皮细胞表达LOX-1 被引量:16
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作者 朱惠莲 唐志红 +3 位作者 刘静 迟东升 王庆 凌文华 《中山大学学报(医学科学版)》 CAS CSCD 北大核心 2005年第6期612-616,共5页
【目的】探讨血凝素样氧化低密度脂蛋白受体1(LOX-1)作为氧化低密度脂蛋白(ox-LDL)的特异性受体在摄取ox-LDL后对人脐静脉血管内皮细胞(HUVECs)表达LOX-1的影响以及LOX-1在ox-LDL诱导其自身表达中所起的作用。【方法】用天然低密度脂蛋... 【目的】探讨血凝素样氧化低密度脂蛋白受体1(LOX-1)作为氧化低密度脂蛋白(ox-LDL)的特异性受体在摄取ox-LDL后对人脐静脉血管内皮细胞(HUVECs)表达LOX-1的影响以及LOX-1在ox-LDL诱导其自身表达中所起的作用。【方法】用天然低密度脂蛋白(n-LDL)、LOX-1的受体阻断剂聚肌苷酸[pdy(Ⅰ)]250μg/mL和爱兰苔胶(carrageenan)以及不同质量浓度的ox-LDL(0,10,20,50,100μg/mL)与HUVECs作用于不同的时间(0,6,12,24,36h),用Realtime RT-PCR测定LOX-1 mRNA的表达水平,用Western blot测定LOX-1蛋白表达水平,并比较加入LOX-1阻断剂前后LOX-1表达的变化。【结果】在HUVECs中加入不同质量浓度的ox-LDL(0,10,20,50,100μg/mL),各组剂量的ox-LDL都可以增加LOX-1 mRNA和蛋白的表达(P<0.01),在10~50μg/mL的剂量范围内有明显的剂量-效应关系。但n-LDL对LOX-1的表达元影响。随着ox-LDL与HUVECs作用时间的延长,LOX-1 mRNA和蛋白的表达显著升高(P<0.01),在6~24h内呈明显的时间-效应关系(P<0.01)。HUVECs预先与250μg/mL的poly(Ⅰ)或carrageenan作用2h,然后再加入50μg/mL的ox-LDL作用24h。poly(Ⅰ)和carrageenan都可以显著抑制ox-LDL诱导的LOX-1 mRNA和蛋白的表达(P<0.01)。【结论】Ox-LDL可以诱导HUVECs LOX-1的表达,该诱导作用可被LOX-1的阻断剂部分拮抗。表明LOX-1不仅特异性地结合ox-LDL,而且介导ox-LDL对LOX-1表达的上调作用。 展开更多
关键词 氧化低密度脂蛋白 血管内皮细胞 血凝素样氧化低密度脂蛋白受体1
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沉默VCAM-1基因降低ox-LDL诱导的HUVECs氧化损伤和凋亡 被引量:6
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作者 刘刚 郭山岭 +1 位作者 胡永寸 刘慧 《基础医学与临床》 CSCD 2019年第10期1423-1426,共4页
目的探讨血管细胞黏附分子-1(VCAM-1)对氧化低密度脂蛋白(ox-LDL)诱导的人脐静脉内皮细胞(HUVECs)氧化损伤及凋亡的影响。方法将体外培养的HUVECs随机分为对照组、ox-LDL组(加入100μg/mL ox-LDL培养24 h)、siRNA-NC组和siRNA-VCAM-1干... 目的探讨血管细胞黏附分子-1(VCAM-1)对氧化低密度脂蛋白(ox-LDL)诱导的人脐静脉内皮细胞(HUVECs)氧化损伤及凋亡的影响。方法将体外培养的HUVECs随机分为对照组、ox-LDL组(加入100μg/mL ox-LDL培养24 h)、siRNA-NC组和siRNA-VCAM-1干预组。在Lipofectamine 2000介导下将siRNA-NC或siRNA-VCAM-1转染HUVECs。Western blot检测VCAM-1蛋白水平,MTT法检测细胞活性,流式细胞计量术检测细胞凋亡率和活性氧(ROS)活性,试剂盒检测丙二醛(MDA)和超氧化物歧化酶(SOD)水平。结果VCAM-1在ox-LDL诱导的HUVECs表达量上调(P<0.05);siRNA-VCAM-1显著降低在ox-LDL诱导的HUVECs VCAM-1蛋白水平(P<0.05);下调VCAM-1能够增加细胞活性(P<0.05),降低凋亡率和ROS及MDA水平(P<0.05),升高SOD活性(P<0.05)。结论下调VCAM-1可增加HUVECs活性、降低凋亡及抑制氧化应激反应。 展开更多
关键词 血管细胞黏附分子-1 氧化性低密度脂蛋白 人脐静脉内皮细胞 氧化应激
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MiR-590-5p对ox-LDL诱导血管内皮细胞凋亡以及LOX-1表达的影响 被引量:8
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作者 秦冰 肖波 +1 位作者 姜婷 杨欢 《中南大学学报(医学版)》 CAS CSCD 北大核心 2012年第7期675-681,共7页
目的:研究miR-590.5p对氧化低密度脂蛋白(ox-LDL)诱导人脐静脉内皮细胞(HUVECs)凋亡过程中血凝素样氧化低密度脂蛋白受体1(LOX-1)表达的调节作用,观察miR-590.5p对HUVECs凋亡的影响。方法:HUVECs经ox-LDL(50/ag/mL)作用... 目的:研究miR-590.5p对氧化低密度脂蛋白(ox-LDL)诱导人脐静脉内皮细胞(HUVECs)凋亡过程中血凝素样氧化低密度脂蛋白受体1(LOX-1)表达的调节作用,观察miR-590.5p对HUVECs凋亡的影响。方法:HUVECs经ox-LDL(50/ag/mL)作用不同时间(0-48h)。AnnexinV-FITC/PI双染流式细胞仪(FCM)检测细胞凋亡率,实时荧光定量PCR(RT-qPCR)检测miR-590-Sp的表达变化。HUVECs转染miR-590-Sp模拟物(miR-590-5pmimics)后ox-LDL继续作用48h-RT-qPCR和Western印迹分别检测LOX.1mRNA和蛋白的表达情况。FCM检测HUVECs凋亡率的变化。结果:随ox-LDL作用时间的延长,HUVECs凋亡率逐渐升高,miR-590-5p表达逐渐下调。miR-590-5p模拟物转染后可以降低LOX.1mRNA和蛋白的表达,并抑制ox-LDL诱导的HUVECs凋亡。结论:miR-590-5p可抑制ox-LDL诱导的HUVECs凋亡,其机制可能与下调LOX-1基因表达有关。 展开更多
关键词 miR-590-5p 氧化低密度脂蛋白 人脐静脉内皮细胞 凋亡 血凝素样氧化低密度脂蛋白受体1 动脉粥样硬化
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ox-LDL检测在糖尿病肾病患者中的价值 被引量:3
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作者 许红兰 万美燕 +1 位作者 夏平 邹作君 《实用临床医药杂志》 CAS 2015年第3期47-49,56,共4页
目的探讨ox-LDL检测在2型糖尿病肾病患者中的价值。方法将90例糖尿病肾病患者分为正常蛋白尿组、微量蛋白尿组和大量蛋白尿组。另选取20例健康者作为正常对照组。检测血ox-LDL浓度、尿微量白蛋白、尿8-OHd G、N-乙酰?β?氨基葡萄糖苷酶(... 目的探讨ox-LDL检测在2型糖尿病肾病患者中的价值。方法将90例糖尿病肾病患者分为正常蛋白尿组、微量蛋白尿组和大量蛋白尿组。另选取20例健康者作为正常对照组。检测血ox-LDL浓度、尿微量白蛋白、尿8-OHd G、N-乙酰?β?氨基葡萄糖苷酶(NAG)等指标。结果糖尿病组血ox-LDL水平显著高于正常对照组(P<0.01);大量蛋白尿组的血oxLDL水平明显高于微量蛋白尿组及正常蛋白尿组(P<0.01)。糖尿病肾病患者血ox-LDL水平与总胆固醇、低密度脂蛋白、甘油三酯及脉压差呈正相关,与BMI及HDL-C呈负相关。ox-LDL水平与尿微量白蛋白、尿8-OHd G、NAG、α2-MG、FDP呈显著正相关。结论糖尿病肾病患者随着蛋白尿的增多其脂质的氧化应激水平增强,且脂质氧化应激作为重要因素参与糖尿病肾病的发生与发展。 展开更多
关键词 糖尿病肾病 氧化应激 ox-LDL 尿8-OHd G
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光丝诱导大气等离子体化学反应生成的一氧化氮测量
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作者 张梦 汪露萍 +3 位作者 黄倩 邱选兵 李传亮 邓伦华 《量子电子学报》 CAS CSCD 北大核心 2024年第2期207-214,共8页
大气等离子体会诱导化学反应,一氧化氮(NO)是大气化学反应的主要产物之一,对其大气浓度的准确测量有助于揭示其大气化学反应机理并优化大气等离子体应用。在静态密闭反应池中,利用脉冲宽度35 fs、工作波长800 nm的脉冲激光生成光丝等离... 大气等离子体会诱导化学反应,一氧化氮(NO)是大气化学反应的主要产物之一,对其大气浓度的准确测量有助于揭示其大气化学反应机理并优化大气等离子体应用。在静态密闭反应池中,利用脉冲宽度35 fs、工作波长800 nm的脉冲激光生成光丝等离子体并诱导大气化学反应,进而采用中红外激光吸收光谱技术,实时测量了NO浓度随空气气压、反应时间的变化。在不同气压下,NO浓度随反应时间的增加而增加直至保持稳定,但NO达到稳定浓度所需要的反应时间随空气气压增加而延长。受到三体复合反应的影响,NO的累积体积比浓度从低气压时的400×10^(-6)以上减小到常压时(一个大气压)的120×10^(-6)左右。 展开更多
关键词 光谱学 超短脉冲激光 大气化学反应 一氧化氮 中红外光谱
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