期刊文献+
共找到4,934篇文章
< 1 2 247 >
每页显示 20 50 100
羚牛IFN-γ基因克隆、生物信息学分析与原核表达
1
作者 柳丽 姚宇航 +4 位作者 刘晨阳 张文涛 马俊杰 昝林森 成功 《西北农业学报》 北大核心 2025年第2期319-328,共10页
旨在研究羚牛γ干扰素(IFN-γ)基因结构与功能,为进一步增强羚牛的免疫调节能力提供理论依据。通过RT-PCR方法克隆羚牛IFN-γ基因,并运用多种生物信息学分析工具对其结构与功能进行深入研究。将IFN-γ基因序列连入原核表达载体,并转化... 旨在研究羚牛γ干扰素(IFN-γ)基因结构与功能,为进一步增强羚牛的免疫调节能力提供理论依据。通过RT-PCR方法克隆羚牛IFN-γ基因,并运用多种生物信息学分析工具对其结构与功能进行深入研究。将IFN-γ基因序列连入原核表达载体,并转化大肠杆菌诱导表达。结果显示,羚牛IFN-γcDNA序列全长501 bp,编码166个氨基酸。蛋白高级结构预测结果显示,二级结构以α螺旋为主,存在13个磷酸化修饰位点,并含有1个信号肽、1个低度复杂区、1个跨膜结构域及1个IFN-γ结构域,其中IFN-γ结构域位于胞外区。序列比对分析发现其与绵羊、山羊、家牛、水牛、人、黑猩猩、小鼠、鸡的核苷酸序列同源性分别为99.0%、98.8%、97.2%、96.2%、75.8%、75.4%、64.1%、54.1%,氨基酸序列同源性分别为99.4%、99.4%、95.8%、95.8%、62.7%、62.7%、43.9%、33.5%。系统进化树分析结果显示,羚牛与山羊、绵羊的亲缘关系最近。经SDS-PAGE和Western-blot检测发现,重组IFN-γ蛋白以可溶性形式大量表达,分子质量约为34 ku。通过密码子优化及不同浓度IPTG诱导表达等原核表达优化策略发现,密码子优化能促进重组蛋白的高效表达,且最佳诱导浓度为0.9 mmol·L^(-1)。 展开更多
关键词 羚牛 ifn 基因克隆 生物信息学分析 原核表达 IPTG诱导
下载PDF
IFN-γ、IL-2联合检测对老年发热患者结核病诊断的价值
2
作者 李倩倩 黄梦昕 +2 位作者 李家斌 郜玉峰 王保贵 《中国医学创新》 2025年第2期153-156,共4页
目的:探索结核特异性细胞因子γ干扰素(IFN-γ)、白细胞介素-2(IL-2)联合检测在老年发热患者结核病诊断中的价值。方法:回顾性分析2022年1月—2024年3月于安徽医科大学附属阜阳人民医院感染科就诊的≥60岁因反复发热住院患者127例。所... 目的:探索结核特异性细胞因子γ干扰素(IFN-γ)、白细胞介素-2(IL-2)联合检测在老年发热患者结核病诊断中的价值。方法:回顾性分析2022年1月—2024年3月于安徽医科大学附属阜阳人民医院感染科就诊的≥60岁因反复发热住院患者127例。所有患者在进行相关检查后不排除结核感染,并进行结核特异性细胞因子IFN-γ、IL-2联合检测及结核分枝杆菌DNA(TB-DNA)扩增检测。比较结核病(TB组)与非结核发热(NTB组)患者的IFN-γ、IL-2水平,并分析IFN-γ、IL-2联合检测诊断结核病的价值。结果:127例发热患者中,结核病18例,占14.2%(18/127),其中肺结核14例,肺外结核4例,非结核发热109例,以感染性发热、慢性阻塞性肺疾病急性加重、肺癌为主。TB组IFN-γ、IL-2水平均显著高于NTB组(P<0.05)。以TB-DNA为金标准,IFN-γ、IL-2联合检测的敏感度为83.3%、特异度为84.4%。受试者操作特征(ROC)曲线显示,IFN-γ、IL-2联合诊断结核病的AUC为0.940[95%CI(0.886,0.994)]。结论:结核特异性细胞因子IFN-γ、IL-2联合检测在老年发热患者结核病诊断中具有良好价值。 展开更多
关键词 老年患者 发热 Γ干扰素 白细胞介素-2 结核病
下载PDF
Anti-oxidation properties of ZrB_2 modified silicon-based multilayer coating for carbon/carbon composites at high temperatures 被引量:8
3
作者 李贺军 姚西媛 +2 位作者 张雨雷 姚栋嘉 王少龙 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第7期2094-2099,共6页
To improve the anti-oxidation ability of silicon-based coating for carbon/carbon (C/C) composites at high temperatures, a ZrB2 modified silicon-based multilayer oxidation protective coating was prepared by pack ceme... To improve the anti-oxidation ability of silicon-based coating for carbon/carbon (C/C) composites at high temperatures, a ZrB2 modified silicon-based multilayer oxidation protective coating was prepared by pack cementation. The phase composition, microstructure and oxidation resistance at 1773, 1873 and 1953 K in air were investigated. The prepared coating exhibits dense structure and good oxidation protective ability. Due to the formation of stable ZrSiO4-SiO2 compound, the coating can effectively protect C/C composites from oxidation at 1773 K for more than 550 h. The anti-oxidation performance decreases with the increase of oxidation temperature. The mass loss of coated sample is 2.44% after oxidation at 1953 K for 50 h, which is attributed to the decomposition of ZrSiO4 and the volatilization of SiO2 protection layer. 展开更多
关键词 C/C composites COATING ZRB2 anti-oxidation properties
下载PDF
Study on Anti-oxidation and Inhibitory Effect on Nonenzymatic Glycation Reaction of Fermentation Extract from Biotransformation of Ginkgo biloba L. (EGB) by Hericium erinaceus 被引量:3
4
作者 黄达明 常为众 +3 位作者 张志才 崔凤杰 肖香 钱静亚 《Agricultural Science & Technology》 CAS 2008年第2期10-13,共4页
[ Objective] In order to study the anti-oxidation and inhibitory effect on nonenzymatic glycation reaction of EGB fermentation extraction biotransformed by Hericium erinaceus. [ Method ] The free radical scavenging ab... [ Objective] In order to study the anti-oxidation and inhibitory effect on nonenzymatic glycation reaction of EGB fermentation extraction biotransformed by Hericium erinaceus. [ Method ] The free radical scavenging ability and reducing capacity of DPPH as well as inhibitory rate of nonenzymatic glycation reaction were measured targets for comparing changes of anti-oxidation and inhibitory effect on nonenzymatic glycation reaction of fermentation lyophilizer and fermentation extraction before and after EGB fermention adsorbed by AB-8 macroporous resin. The EGB fermention was biotransformed by Hericium erinaceus. [ Result ] After adsorbed by AB-8 macroporous resin, the bioactive matters were concentrated and separated. The free radical scavenging rate, reducing capacity and inhibitory rate of nonenzymatic glycation reaction were increased significantly after adsorbed by AB-8 macroporous resin. [ Conclusion] AB-8 macroporous resin could be used for preliminary concentration of EGB fermentation which was biotransformed by Hericium erinaceus. 展开更多
关键词 BIOTRANSFORMATION anti-oxidation Nonenzymatic glycation reaction
下载PDF
The Technology Research of Anti-oxidation Peptide Preparation by Alkaline Protease Hydrolyzing Wheat Germ Meal 被引量:7
5
作者 刁大鹏 黄继红 +6 位作者 冯军伟 侯银臣 惠明 游倩倩 苏雪峰 王文 杨铭乾 《Agricultural Science & Technology》 CAS 2014年第2期182-186,共5页
Wheat germ meal is the by production of oil extracting, and a great quantity of it has been wasted, thus the quantity of lost protein is great. In order to use wheat germ meal proteins adequately, wheat germ proteins ... Wheat germ meal is the by production of oil extracting, and a great quantity of it has been wasted, thus the quantity of lost protein is great. In order to use wheat germ meal proteins adequately, wheat germ proteins were hydrolyzed to anti-oxidation peptides by using alkaline protease. Through the single factor analysis and regression analysis, the optimized experiment conditions of hydrolysising wheat germ meal to wheat germ peptides were enzymatic quantity 0.8%(w/w), material to liquid ratio 1∶12.3, enzymolysis time 2.1 h. Under these conditions, the scavenging effect was 49.78%,the DH was 22% and peptides content in enzymatic hydrolysate was 1.9%(w/w).By SDS-PAGE electrophoresis,the molecular weight range of wheat germ peptides were below 10 ku and most were between 4.54 and 5.63 ku.The wheat germ proteins could be used ful y and grain resources would be saved. 展开更多
关键词 Ikaline protease Wheat germ meal anti-oxidation peptides MOLECULARWEIGHT
下载PDF
IFN-β通过STAT1诱导SARI表达抑制AML细胞增殖并促进凋亡
6
作者 林艳凤 洪小颖 +4 位作者 黄莹莹 王小花 吴玮 林东红 薛龑 《中国免疫学杂志》 CAS CSCD 北大核心 2024年第6期1137-1141,共5页
目的:探讨IFN-β诱导SARI表达对急性粒细胞性白血病(AML)细胞增殖、凋亡的作用,并筛选其潜在的调控分子。方法:qPCR、Western blot筛选SARI低表达的AML细胞作为实验细胞株;不同浓度IFN-β干预AML细胞,于不同时间采用qPCR、Western blot... 目的:探讨IFN-β诱导SARI表达对急性粒细胞性白血病(AML)细胞增殖、凋亡的作用,并筛选其潜在的调控分子。方法:qPCR、Western blot筛选SARI低表达的AML细胞作为实验细胞株;不同浓度IFN-β干预AML细胞,于不同时间采用qPCR、Western blot检测SARI表达,选取IFN-β作用的适当浓度和时间;采用RNA-Seq转录组测序及KEGG富集分析初步筛选IFN-β诱导AML细胞SARI表达的潜在调控分子;通过相应分子抑制剂联合IFN-β处理AML细胞,MTS法检测细胞增殖,流式细胞术检测细胞凋亡;明确该分子参与IFN-β诱导SARI表达对AML细胞增殖及凋亡的作用。结果:HL60和NB4细胞SARI表达相对较低,选为实验细胞株;1 ng/ml IFN-β作用12 h后AML细胞SARI表达升高且细胞增殖被抑制,凋亡增多;筛选STAT1为IFN-β诱导SARI表达的潜在调控分子;抑制STAT1后,IFN-β对AML细胞SARI表达、增殖抑制、凋亡促进的作用被明显逆转。结论:IFN-β可通过STAT1诱导AML细胞SARI表达,抑制细胞增殖,促进细胞凋亡。 展开更多
关键词 ifn SARI STAT1 AML 增殖 凋亡
下载PDF
鸭坦布苏病毒非结构蛋白亚细胞定位及其在IFN-β信号通路中的作用
7
作者 张蓉蓉 潘爱銮 +6 位作者 吴娟 方兵兵 汪最 卢琴 张腾飞 温国元 罗青平 《中国畜牧兽医》 CAS CSCD 北大核心 2024年第12期5470-5478,共9页
【目的】探究鸭坦布苏病毒(Duck Tembusu virus,DTMUV)非结构蛋白的亚细胞定位及其在β-干扰素(IFN-β)信号通路中的作用。【方法】通过RT-PCR法扩增DTMUV的7个非结构蛋白(NS1、NS2A、NS2B、NS3、NS4A、NS4B和NS5)基因,将其克隆至真核... 【目的】探究鸭坦布苏病毒(Duck Tembusu virus,DTMUV)非结构蛋白的亚细胞定位及其在β-干扰素(IFN-β)信号通路中的作用。【方法】通过RT-PCR法扩增DTMUV的7个非结构蛋白(NS1、NS2A、NS2B、NS3、NS4A、NS4B和NS5)基因,将其克隆至真核表达载体pCAGGS-HA,构建重组真核表达质粒,并分别转染至HEK-293T细胞,通过Western blotting检测蛋白表达;利用间接免疫荧光试验检测非结构蛋白的亚细胞定位情况,通过双荧光素酶报告试验研究DTMUV的非结构蛋白对鸭源IFN-β启动子活性的影响。【结果】试验成功构建DTMUV的7个非结构蛋白带HA标签的真核表达质粒。Western blotting结果显示,真核表达非结构蛋白均正常表达,NS1、NS2A、NS2B、NS3、NS4A、NS4B和NS5蛋白分子质量大小分别为38、25、14.4、68、13.9、28和100 ku。间接免疫荧光试验结果显示,7个非结构蛋白在细胞内的表达形态不一,主要定位在细胞浆中。双荧光素酶报告试验结果表明,与对照组相比,过表达NS2B和NS4B蛋白后,鸭源IFN-β启动子活性极显著降低(P<0.01)。【结论】本研究成功构建了DTMUV的7个非结构蛋白的真核表达质粒,非结构蛋白主要表达于细胞浆中,其中NS2B和NS4B蛋白具有颉颃IFN-β活性的功能。试验结果为DTMUV的免疫逃逸研究提供了一定的理论依据,并为深入探究DTMUV在宿主天然免疫信号通路中的作用机制提供了试验材料。 展开更多
关键词 鸭坦布苏病毒 非结构蛋白 亚细胞定位 ifn-β信号通路
下载PDF
结核分枝杆菌特异性IFN-γ、IL-2联合检测在肺结核与细菌性肺炎鉴别诊断中的应用
8
作者 许静 王伟 李团团 《中国感染控制杂志》 CAS CSCD 北大核心 2024年第9期1173-1177,共5页
目的评价结核分枝杆菌特异性细胞因子干扰素-γ(IFN-γ)、白细胞介素-2(IL-2)双因子联合检测在肺结核与细菌性肺炎鉴别诊断中的应用价值。方法选择阜阳市人民医院2022年1月-2023年10月呼吸科住院患者91例,明确诊断为肺结核患者45例(肺... 目的评价结核分枝杆菌特异性细胞因子干扰素-γ(IFN-γ)、白细胞介素-2(IL-2)双因子联合检测在肺结核与细菌性肺炎鉴别诊断中的应用价值。方法选择阜阳市人民医院2022年1月-2023年10月呼吸科住院患者91例,明确诊断为肺结核患者45例(肺结核组)和细菌性肺炎患者46例(肺炎组),均进行双因子联合检测,比对分析双因子联合检测与C反应蛋白(CRP)对肺结核和细菌性肺炎鉴别诊断的效果。结果使用双因子联合检测对肺结核与细菌性肺炎进行鉴别诊断,灵敏度为86.7%、特异度为84.8%,受试者工作特征曲线下面积(AUC)值为0.928(95%CI:0.870~0.986),与CRP的鉴别诊断效果相比差异有统计学意义(P<0.05)。结论结核分枝杆菌特异性细胞因子IFN-γ、IL-2联合检测在鉴别肺结核与细菌性肺炎时具有较高的应用价值,能为临床肺结核和细菌性肺炎的鉴别诊断提供依据。 展开更多
关键词 肺结核 细菌性肺炎 ifn IL-2 联合检测 鉴别诊断
下载PDF
ANTI-HYPOXIA AND ANTI-OXIDATION EFFECTS OF AMINOPHYLLINE ON HUMAN WITH ACUTE HIGH-ALTITUDE EXPOSURE 被引量:8
9
作者 Bo Yang Guang-yi Wang +3 位作者 Bin Chen Rong-bin Qin Si Lang Zha Xi Lian Chen 《Chinese Medical Sciences Journal》 CAS CSCD 2007年第1期62-65,共4页
Objective To investigate the anti-hypoxia and anti-oxidation effects of aminophylline on human with acute high- altitude exposure. Mothoda Totally 100 young male army members newly recruited from Sichuan province (4... Objective To investigate the anti-hypoxia and anti-oxidation effects of aminophylline on human with acute high- altitude exposure. Mothoda Totally 100 young male army members newly recruited from Sichuan province (400 meters above sea level) were enrolled. They were randomly divided into two groups: 50 in aminophylline group (A group) and 50 in control group ( C group). A group and C group orally took aminophylline and placebo respectively for 10 days, 7 days before entering Lhasa (3 658 meters above sea level) by air and 3 days after it. Several parameters were measured at three time points: before drug taken, 7 days after drug taken, and 3 days after ascending high altitude. These parameters included serum levels of nitric oxide (NO), superoxide dismutase (SOD), catalase (CAT), hydrogen dioxide (H2O2), lactic acid (LA), as well as arterial oxygen saturation (SO2), arterial oxygen partial pressure (PaO2), and arterial carbon dioxide partial pressure (PaCO2). Statistical analysis was conducted to compare the difference between two groups with Stata 7.0 software system. Results There were no statistical differences between groups in hypoxia and oxidation indicators before and after drug taken in plain area. Three days after ascending high altitude, the serum levels of SOD, CAT, H202, LA, PaCO2 increased in both groups, yet to a much larger degree in C group than A group (P 〈0. 01 ) ; and NO, SO2 , PaO2 decreased more markedly in C group ( P 〈 0. 05 for NO, P 〈 0. 0001 for SO2 and PaO2 ). Conclusion Aminophylline has significant anti-hypoxia and anti-oxidation effects at high altitude. 展开更多
关键词 AMINOPHYLLINE high altitude ANTI-HYPOXIA anti-oxidation
下载PDF
Preparation and Properties of Anti-oxidation Inorganic Nano-coating for Low Carbon Steel at an Elevated Temperature 被引量:3
10
作者 魏连启 叶树峰 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第4期48-52,共5页
A new kind of anti-oxidation inorganic nano-coating for the common low carbon steel was prepared. It included magnesite mineral, metallurgic dust and silicate adhesive as the main raw materials. The nano-coating could... A new kind of anti-oxidation inorganic nano-coating for the common low carbon steel was prepared. It included magnesite mineral, metallurgic dust and silicate adhesive as the main raw materials. The nano-coating could be sprayed directly onto the low carbon steel slab even though with hot surface as far as under 1000 ℃ . And at the same time, a compact thin nano-film was formed, and the film would inhibit the oxygen into the interface of the steel body and decrease the loss of weight because of oxidation. The loss was decreased by about 60% or more. The properties and mechanism of oxidation resistance of the coating were discussed through XRD, TG-DTA and SEM. The experimental results show that many reactions would happen among the companents of the coating and then many microspheres with the size of 80- 100nm generated in the system. By using the heat of the steel body, the silicate adhesive would interact with the microspheres, and the other components of the coating would be soft and sintered so that when the coating was sprayed onto the suface of the steel slab , the intact and compact film could be formed and adhesive with the steel body. Besides the special properties of anti- oxidation, the coating could prevent the volatilization of microelement in the steel such as silicate and carbon at a high temperature. So it can improve the quality and output of steel with this new kind of nano-coating. 展开更多
关键词 low carbon steel anti-oxidation nano-coating oxidation loss metallurgh dust
下载PDF
高脂肪饮食促进TLR2的表达促进3T3L1脂肪细胞分泌IFN-γ诱导胰岛素抵抗的发生及发展 被引量:1
11
作者 白继昌 谈力欣 +2 位作者 刘赞朝 杨洋 朱亚军 《河北医学》 CAS 2024年第3期405-411,共7页
目的:探讨高脂饮食诱导胰岛素抵抗的机制,以及了解高脂饮食诱导胰岛素抵抗的脂肪细胞的表型变化。方法:雄性C57 BL/6 J小鼠,给予正常饮食和高脂饮食。从正常饮食或高脂饮食喂养2周的小鼠中分离附睾脂肪组织。实时荧光定量RT-PCR检测γ-... 目的:探讨高脂饮食诱导胰岛素抵抗的机制,以及了解高脂饮食诱导胰岛素抵抗的脂肪细胞的表型变化。方法:雄性C57 BL/6 J小鼠,给予正常饮食和高脂饮食。从正常饮食或高脂饮食喂养2周的小鼠中分离附睾脂肪组织。实时荧光定量RT-PCR检测γ-干扰素(Interferonγ,IFN-γ)和toll样受体2(toll-like receptor 2,TLR2)mRNA的表达。流式细胞术来检测表达TLR2或IFN-γ的脂肪细胞的数量。苏木精-伊红染色分析胰腺组织。免疫组化分析脂肪组织中TLR2和IFN-γ的表达。FFA或Zymosan A处理3T3-L1脂肪细胞,并通过实时荧光定量RT-PCR检测IFN-γ和TLR2 mRNA的表达。结果:对脂肪细胞中基因表达谱的分析表明,高脂肪摄入诱导了IFN-γ和TLR2的表达提高。流式细胞术分析显示存在共表达TLR2和IFN-γ的脂肪细胞(TLR2/IFN-γ脂肪细胞),与皮下脂肪组织相比,高脂肪摄入增加了内脏脂肪组织中TLR2/IFN-γ脂肪细胞的数量。游离脂肪酸通过TLR2信号增加3T3-L1脂肪细胞中IFN-γ的表达。结论:TLR2/IFN-γ脂肪细胞可能通过诱导内脏脂肪组织IFN-γ的表达,参与高脂诱导的胰岛素抵抗的发生。 展开更多
关键词 TLR2 脂肪细胞 ifn 胰岛素抵抗
下载PDF
Microstructure of a Mo-Si-C-N multi-layered anti-oxidation coating on carbon/carbon composites by fused slurry 被引量:1
12
作者 LAI Zhonghong MENG Songhe +1 位作者 ZHU Jingchuan JEON Jaeho 《Rare Metals》 SCIE EI CAS CSCD 2009年第5期460-464,共5页
A Mo-Si-C-N multi-layered anti-oxidation coating was in-situ fabricated by introducing nitrogen atmosphere during the fused sintering of Mo-Si slurry pre-layer on carbon/carbon composites. The phase composition and mi... A Mo-Si-C-N multi-layered anti-oxidation coating was in-situ fabricated by introducing nitrogen atmosphere during the fused sintering of Mo-Si slurry pre-layer on carbon/carbon composites. The phase composition and microstructure of the Mo-Si-C-N coating were characterized by X-ray diffractometry, optical microscopy, scanning electron microscopy with energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. The Mo-Si-C-N coating exhibited a three-layered structure. Besides the MoSi2/Si main-layer and the SiC bonding-layer, a surface layer of about 10 μm in thickness was synthesized on the coating surface. The surface layer mainly consisted of SiC nanowires and contained some Si3N4 and Si phases. SiC nanowires of 10 to 200 nm in diameter presented a terrace and distortion structure. Transmission electron microscopy indicated that the SiC nanowires grew along the preferred 〈111〉 direction. During oxidation test, SiC nanowires transmuted into SiO2 glass, which can play an important role in improving the oxidation resistance of C/C composites. 展开更多
关键词 C/C composites COATING MICROSTRUCTURES anti-oxidation
下载PDF
Fabrication of MoSi;coatings on molybdenum and its high-temperature anti-oxidation properties 被引量:1
13
作者 Lu ZHU Peng CHEN +4 位作者 Zi-ming CAI Pei-zhong FENG Xue-qin KANG Farid AKHTAR Xiao-hong WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第3期935-946,共12页
Industrial spent MoSi_(2)-based materials were used to fabricate oxidation-resistant coatings on molybdenum via slurry painting in air. The microstructure, phase constituent and high-temperature oxidation behaviors of... Industrial spent MoSi_(2)-based materials were used to fabricate oxidation-resistant coatings on molybdenum via slurry painting in air. The microstructure, phase constituent and high-temperature oxidation behaviors of the coatings at 1500 ℃ were explored. The results show that the bonding layer is generated in the coatings after sintering,which strengthens the metallurgical combination between the coating and the substrate because of the formation of diffusion layers. Rare cracks appear in the coating using pure MoSi_(2)(PM coating) while the coating using spent MoSi_(2)(SM coating) is free of cracks due to decreased thermal expansion mismatch. After oxidation, the oxide scale of PM coating possesses large-sized pores while a relatively dense oxide scale is acquired by SM coating. Compared with PM coating, thinner glassy oxide scale with lower mass gain is obtained by SM coating, exhibiting better anti-oxidation properties at 1500 ℃. 展开更多
关键词 recycling spent MoSi2 slurry painting anti-oxidation properties molybdenum substrate
下载PDF
Preparation and Anti-oxidation Mechanism of Mullite/Yttrium Silicate Coatings on C/SiC Composites 被引量:3
14
作者 马青松 cai lihui 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第6期1284-1288,共5页
In order to enhance the oxidation resistance of C/Si C composites, mullite/yttrium silicate coatings were fabricated on C/Si C composites through dip-coating route. Al_2O_3-SiO_2 sol with high solid content was select... In order to enhance the oxidation resistance of C/Si C composites, mullite/yttrium silicate coatings were fabricated on C/Si C composites through dip-coating route. Al_2O_3-SiO_2 sol with high solid content was selected as the raw material for mullite and "silicone resin + Y_2O_3 powder" slurry was used to synthesize yttrium silicate. The microstructure and phase composition of coatings were characterized, and the investigation on oxidation resistance and anti-oxidation mechanism was emphasized. The as-fabricated coatings consisting of SiO_2-rich mullite phase and Y_2Si_2O_7 phase show high density and favorable bonding to C/Si C composites. After oxidized at 1 400 ℃ and 1 500 ℃ for 30 min in static air, the coating-containing C/Si C composites possess 91.9% and 102.4% of the original flexural strength, respectively. The desirable thermal stability of coatings and the further densification of coatings due to viscous flow of rich SiO_2 and Y-Si-Al-O glass are responsible for the excellent oxidation resistance. In addition, the coating-containing composites retain 99.0% of the original flexural strength and the coatings exhibit no cracking and desquamation after 12 times of thermal shock from 1 400 ℃ to room temperature, which are ascribed to the combination of anti-oxidation mechanism and preferable physical and chemical compatibility among C/Si C composites, mullite and Y_2Si_2O_7. The carbothermal reaction at 1 600 ℃ between free carbon in C/Si C substrate and rich SiO_2 in mullite results in severe frothing and desquamation of coatings and obvious degradation in oxidation resistance. 展开更多
关键词 anti-oxidation coatings mullite yttrium silicate C/SiC composites
下载PDF
Orthogonal Test Optimization of Extraction Technology of Total Fla-vonoids from Fruits and Leaves of Prunus mume Sieb. et Zucc. and Its in Vitro Anti-oxidation Activity 被引量:4
15
作者 Xue ZHAI Qian JIN +2 位作者 Haiyan XIANG Fenglin WANG Yuan LIU 《Medicinal Plant》 2017年第2期25-31,36,共8页
[Objectives]To optimize the extraction technology of total flavonoids component,and investigate its in vitro anti-oxidation activity.[Methods]The single factor was inspected firstly. By orthogonal experiment,the best ... [Objectives]To optimize the extraction technology of total flavonoids component,and investigate its in vitro anti-oxidation activity.[Methods]The single factor was inspected firstly. By orthogonal experiment,the best extraction conditions of total flavonoids from fruits and leaves of P. mume Sieb. et Zucc. were determined,and reducing ability of the extracted total flavonoids and its DPPH and ABTS scavenging abilities were explored. [Results] The best extraction technology conditions: solid-liquid ratio of 1∶ 50,ethanol concentration of 50%,extraction time of 2. 5 h,extraction temperature of 85 ℃,two-time extraction. By detecting DPPH and ABTS scavenging abilities of total flavonoids,the anti-oxidation activity of the total flavonoids from fruits and leaves of P. mume Sieb. et Zucc. was analyzed and evaluated. [Conclusions]Fruits and leaves of P. mume Sieb. et Zucc. had a certain in vitro anti-oxidation activity,and heat reflux extraction method of its total flavonoids had high extraction rate and simple and convenient operation,which had some practical value. 展开更多
关键词 Prunus mume Sieb. ET Zucc. FRUITS and LEAVES anti-oxidation TOTAL flavonoids Orthogonal process
下载PDF
Contrastive Study on Content and Anti-oxidation Activity of Total Saponins from Cultivated and Wild Paris Plants in Southwest China 被引量:3
16
作者 Mengjie YU Haiyan XIANG +2 位作者 Shaoshan ZHANG Zhongjie HUANG Yuan LIU 《Medicinal Plant》 2017年第1期7-11,共5页
[Objectives]To study content of total saponins from cultivated and wild Paris herbs in Southwest China,evaluate its in vitro antioxidation activity,and explore the correlation between quality of Paris herbs and produc... [Objectives]To study content of total saponins from cultivated and wild Paris herbs in Southwest China,evaluate its in vitro antioxidation activity,and explore the correlation between quality of Paris herbs and production place,variety,cultivated and wild varieties.[Methods]Colorimetric method of perchloric acid reaction was used,and content of total saponins from Paris herbs was determined by ultraviolet spectrophotometer at 406 nm. [Results]The lowest content of total saponins from cultivated and wild Paris herbs in Southwest China was0. 55%,while the maximum was 12. 24%,with obvious difference. Total saponins from Paris herbs had stronger clearance ability on free radical DPPH and stronger reduction ability on Fe^(3+),and the results showed good dose-effect relationship with concentration. Among them,S6 had the highest clearance ability on DPPH,which reached 89. 66%. In the determination of reduction ability,the absorbance of S16 reached3. 643 and was the highest,with very good reducing property. Content and anti-oxidation capacity of total saponins from Paris herbs in Southwest China did not have obvious correlation with production place,altitude and cultivation but was related to variety. [Conclusions]The quality of Paris herbs in Southwest China was unstable,and their anti-oxidation abilities were also different,and cultivation could not guarantee high quality. It should normalize cultivation,and develop planting industry of Paris herbs,which could guarantee stable supply of Paris herbs and stability and controllability of quality. 展开更多
关键词 CULTIVATED and WILD PARIS herbs UV-VISIBLE spectrophotometry Total saponins anti-oxidation
下载PDF
IFN-γ联合IL-6在菌阴性肺结核诊断中的应用分析 被引量:1
17
作者 刘轩妙 徐俊驰 +1 位作者 岳晓冬 胥萍 《标记免疫分析与临床》 CAS 2024年第3期450-455,475,共7页
目的探讨IFN-γ联合IL-6在菌阴性肺结核临床诊断中的应用及其临床意义。方法收集2021年10月21日至2023年4月27日期间在苏州大学附属传染病医院病例266例。依据肺结核诊断标准(WS288-2017),肺结核患者196例,其中男性130例,女性66例,平均... 目的探讨IFN-γ联合IL-6在菌阴性肺结核临床诊断中的应用及其临床意义。方法收集2021年10月21日至2023年4月27日期间在苏州大学附属传染病医院病例266例。依据肺结核诊断标准(WS288-2017),肺结核患者196例,其中男性130例,女性66例,平均年龄58.4±17.1岁;病灶双侧患者141例,病灶单侧患者55例;菌阳患者92例,菌阴患者104例。职业性尘肺病患者70例,其中男性69例,女性1例,平均年龄62.7±8.9岁。健康对照组20例,其中男性10例,女性10例,平均年龄58.6±6.3岁。采用流式细胞术检测血浆中细胞因子IFN-γ、IFN-α、IL-2、IL-4、IL-5、IL-6、IL-8、TNF-α、IL-10、IL-12P70、IL-1β、IL-17的表达水平,比较不同组别中这12项炎症细胞因子的差异。结果(1)活动性肺结核患者组血浆IFN-γ、IL-6水平显著高于健康对照组以及职业性尘肺病患者组(非结核性肺部疾病对照组)。(2)活动性肺结核患者中,双侧病灶肺结核患者组的血浆IL-6、IL-8水平显著高于单侧病灶肺结核患者组。(3)活动性肺结核患者中,菌阳性肺结核患者组血浆IL-6水平显著高于菌阴性肺结核患者组。(4)活动性肺结核患者中,γ-干扰素释放试验阴性患者组IFN-γ、IL-6水平显著高于健康对照组。(5)菌阴性肺结核患者中,γ-干扰素释放试验阴性患者组IFN-γ、IL-6水平显著高于健康对照组。结论IFN-γ、IL-6、IL-8可反映结核患者的炎症情况、疾病严重程度及细菌负荷,并且IFN-γ联合IL-6可以作为无病原学证据、免疫学检查结果为阴性且具有肺部影像学依据患者诊断的辅助指标,临床医师可以通过IFN-γ、IL-6的表达水平联合肺部影像学证据来为该类患者进行辅助诊断,并评估患者免疫状态,提高患者免疫力,为患者的个性化治疗提供依据。 展开更多
关键词 活动性肺结核 菌阴性肺结核 炎症细胞因子 ifn IL-6
下载PDF
FMDV 3D基因真核表达质粒的构建、表达及对Ⅰ型IFN信号通路的作用
18
作者 苗勤 吴香菊 +4 位作者 齐静 丛晓燕 李均同 王林 杜以军 《山东农业科学》 北大核心 2024年第2期144-150,共7页
本研究旨在构建口蹄疫病毒(Foot-and-mouth disease virus,FMDV)3D基因真核表达质粒,并探究其对Ⅰ型干扰素(interferon,IFN)信号通路的作用。根据GenBank序列合成3D基因并将其插入真核表达载体pXJ41构建真核表达质粒pXJ41-Myc-3D,经PCR... 本研究旨在构建口蹄疫病毒(Foot-and-mouth disease virus,FMDV)3D基因真核表达质粒,并探究其对Ⅰ型干扰素(interferon,IFN)信号通路的作用。根据GenBank序列合成3D基因并将其插入真核表达载体pXJ41构建真核表达质粒pXJ41-Myc-3D,经PCR、双酶切及测序鉴定正确后分别转染HEK-293T细胞和PK-15细胞,Western blotting及间接免疫荧光试验(indirect immunofluorescence assay,IFA)检测3D蛋白在细胞内的表达及定位。通过双荧光素酶报告基因(Luciferase)、Real-time PCR、TCID50等试验检测HEK-293T细胞中过表达3D蛋白对水疱性口炎病毒(Versicular stomatitis virus,VSV)诱导的Ⅰ型IFN信号通路的影响。结果显示,真核表达质粒pXJ41-Myc-3D构建成功;3D蛋白在HEK-293T细胞中表达,大小约为55 kDa,主要定位在细胞核中;3D蛋白抑制了VSV诱导的IFN-β启动子活性和IFN-β mRNA水平,促进了VSV的复制。本研究为深入探究3D蛋白抑制Ⅰ型IFN信号通路的作用机制奠定了基础。 展开更多
关键词 口蹄疫病毒 3D蛋白 真核表达 Ⅰ型ifn信号通路
下载PDF
Comparative study of high temperature anti-oxidation property of sputtering deposited stoichiometric and Si-rich SiC films
19
作者 Hang-Hang Wang Wen-Qi Lu +1 位作者 Jiao Zhang Jun Xu 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第4期700-705,共6页
Stoichiometric and silicon-rich(Si-rich) SiC films were deposited by microwave electron cyclotron resonance(MWECR) plasma enhanced RF magnetron sputtering method.As-deposited films were oxidized at 800℃,900 ℃,and 10... Stoichiometric and silicon-rich(Si-rich) SiC films were deposited by microwave electron cyclotron resonance(MWECR) plasma enhanced RF magnetron sputtering method.As-deposited films were oxidized at 800℃,900 ℃,and 1000 ℃in air for 60 min.The chemical composition and structure of the films were analyzed by x-ray photoelectron spectroscopy(XPS),Raman spectroscopy and Fourier transform infrared spectroscopy(FT-IR).The surface morphology of the films before and after the high temperature oxidation was measured by atomic force microscopy.The mechanical property of the films was measured by a nano-indenter.The anti-oxidation temperature of the Si-rich SiC film is 100 ℃ higher than that of the stoichiometric SiC film.The oxidation layer thickness of the Si-rich SiC film is thinner than that of the stoichiometric SiC film in depth direction.The large amount of extra silicon in the Si-rich SiC film plays an important role in the improvement of its high temperature anti-oxidation property. 展开更多
关键词 SiC anti-oxidation silicon-rich SPUTTERING
下载PDF
化疗联合免疫治疗局部晚期食管癌疗效及对Sil⁃2R、IFN⁃γ、TSGF水平的影响
20
作者 魏丹丹 方金满 +2 位作者 王明喜 王伟 汤振 《分子诊断与治疗杂志》 2024年第8期1524-1528,共5页
目的研究化疗联合免疫治疗局部晚期食管癌(LAEC)疗效及对可溶性白细胞介素⁃2受体(Sil⁃2R)、γ⁃干扰素(IFN⁃γ)及恶性肿瘤特异生长因子(TSGF)水平的影响。方法选择2021年3月至2023年7月于中国科学院合肥肿瘤医院治疗的LAEC患者106例,依... 目的研究化疗联合免疫治疗局部晚期食管癌(LAEC)疗效及对可溶性白细胞介素⁃2受体(Sil⁃2R)、γ⁃干扰素(IFN⁃γ)及恶性肿瘤特异生长因子(TSGF)水平的影响。方法选择2021年3月至2023年7月于中国科学院合肥肿瘤医院治疗的LAEC患者106例,依据随机数字表法将106例患者分为试验组(n=53)、对照组(n=53)。对照组行标准化疗,试验组行化疗联合免疫治疗。观察两组临床疗效、不良反应,比较两组治疗前后血清程序性死亡配体1(PD⁃L1)、程序性死亡受体1(PD⁃1)、Sil⁃2R、IFN⁃γ、TSGF水平。结果试验组客观缓解率(ORR)、疾病控制率(DCR)均高于对照组,差异有统计学意义(P<0.05)。两组治疗期间各不良反应分级比较差异无统计学意义(P>0.05)。治疗后,试验组血清PD⁃L1、PD⁃1及Sil⁃2R、TSGF水平均低于对照组,血清IFN⁃γ水平高于对照组,差异有统计学意义(P<0.05)。结论化疗联合免疫治疗可有效降低LAEC患者免疫检查点活性,增强机体免疫,可促进产生IFN⁃γ,抑制Sil⁃2R、TSGF生成,疗效较好,且不增加不良反应,具有一定的临床应用价值。 展开更多
关键词 化疗 免疫治疗 局部晚期食管癌 Sil⁃2R ifn⁃γ TSGF
下载PDF
上一页 1 2 247 下一页 到第
使用帮助 返回顶部