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Detection of serum TNF-α,IFN-γ,IL-6 and IL-8 in patients with hepatitis B 被引量:55
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作者 WANG Jing Yan, WANG Xue Lian and LIU Pei 《World Journal of Gastroenterology》 SCIE CAS CSCD 1999年第1期43-45,共3页
AIM To assess the possible roles of cytokines (TNF α, IFN γ, IL 6 and IL 8) in liver damage of hepatitis B. METHODS The serum TNF α, IFN γ, IL 6 and IL 8 were detected by ELISA in 66 patients with hepat... AIM To assess the possible roles of cytokines (TNF α, IFN γ, IL 6 and IL 8) in liver damage of hepatitis B. METHODS The serum TNF α, IFN γ, IL 6 and IL 8 were detected by ELISA in 66 patients with hepatitis B and 20 healthy blood donors. RESULTS TNF α and IL 6 in all types of clinical hepatitis B were significantly higher than those in healthy blood donors ( P <0 05); meanwhile the levels of TNF α, IFN γ, IL 6 and IL 8 in the patients with fulminant hepatitis B were much higher than those in the patients with acute hepatitis B ( P <0 05); the level of TNF α was positively correlated with the levels of IFN γ, Il 6 and IL 8 in all types of hepatitis B ( r IFN =0 24, r IL 6 =0 35, r IL 8 =0 44) and the TNF α, IFN γ, IL 6 and IL 8 were positively correlated with serum bilirubin ( P <0 05). Dynamic changes of these cytokines were observed in the course of acute and fulminant hepatitis. The level of IFN γ peaked in the initial period of acute hepatitis and early stage of hepatic coma in fulminant hepatitis; TNF α, IL 6 and IL 8 increased with exacerbation, and reached a peak when the liver damage was most serious, then decreased when patient conditions were improved. CONCLUSION The increased cytokines were related to the inflammation of liver cells and multiple factors may play certain roles in liver damage. 展开更多
关键词 HEPATITIS B TNF α IFN γ IL 6 IL 8
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有机碲氧化物催化合成α,β-不饱和酮和2,4-二烯酮 被引量:32
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作者 钟琦 陆荣健 《应用化学》 CAS CSCD 北大核心 1990年第3期89-92,共4页
α,β-不饱和酮是重要的有机合成中间体,常用醇钠或氢氧化钠作催化剂由醛酮缩合合成,这时常由于强碱而发生副反应。Cava曾报道双对-甲氧苯基氧化碲(BMPTO)对醇醛缩合有一定催化作用。本文以BMPTO为催化剂,通过Claisen-Schmidt反应合成... α,β-不饱和酮是重要的有机合成中间体,常用醇钠或氢氧化钠作催化剂由醛酮缩合合成,这时常由于强碱而发生副反应。Cava曾报道双对-甲氧苯基氧化碲(BMPTO)对醇醛缩合有一定催化作用。本文以BMPTO为催化剂,通过Claisen-Schmidt反应合成了一系列α,β-不饱和酮和2,4-二烯酮。所得产物及其结构表征结果列于表1。 展开更多
关键词 二烯酮 不饱和酮 BMPTO催化
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Mir-217通过 Sirt1/HIF-1α信号通路介导高糖诱导的大鼠肾小球系膜细胞炎症反应及纤维化 被引量:41
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作者 邵滢 吕川 +2 位作者 吴灿 周月宏 王秋月 《中华内分泌代谢杂志》 CAS CSCD 北大核心 2016年第7期556-563,共8页
目的探讨MicroRNA-217(Mir-217)、沉默信息调节因子1(Sirt1)及低氧诱导因子1α(HIF-1α)在高糖诱导大鼠肾小球系膜细胞( RMCs)炎症反应及纤维化中的作用。方法以Sirt1激活剂白藜芦醇预处理体外高糖培养的RMCs或转染Sirt1小干扰... 目的探讨MicroRNA-217(Mir-217)、沉默信息调节因子1(Sirt1)及低氧诱导因子1α(HIF-1α)在高糖诱导大鼠肾小球系膜细胞( RMCs)炎症反应及纤维化中的作用。方法以Sirt1激活剂白藜芦醇预处理体外高糖培养的RMCs或转染Sirt1小干扰RNA( siRNA)、HIF-1αsiRNA及Mir-217抑制物。采用实时定量PCR检测Mir-217、Sirt1 mRNA、HIF-1αmRNA的表达,Western印迹检测Sirt1、HIF-1α、结缔组织生长因子(CTGF)、内皮素1、纤连蛋白(FN)的表达,酶联免疫吸附法检测转化生长因子-β1(TGF-β1)、血管内皮生长因子( VEGF)的表达。结果高糖促进RMCs中Mir-217、HIF-1α、CTGF、ET-1、FN、TGF-β1及VEGF的表达(均P&lt;0.01),下调Sirt1表达(P&lt;0.01)。 Mir-217基因沉默或25μmol/L白藜芦醇预处理可逆转高糖刺激的HIF-1α、CTGF、内皮素1、FN、TGF-β1及VEGF表达(均P&lt;0.01)。结论在高糖培养的RMCs中,Mir-217通过调节Sirt1/HIF-1α通路促进炎症反应及纤维化,为Sirt1在糖尿病肾病中发挥保护作用的机制提供新的理论依据。 展开更多
关键词 MicroRNA MicroRNA-217 沉默信息调节因子1 低氧诱导因子1 α 糖尿病肾病
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面向敏感值的个性化隐私保护 被引量:40
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作者 韩建民 于娟 +1 位作者 虞慧群 贾泂 《电子学报》 EI CAS CSCD 北大核心 2010年第7期1723-1728,共6页
现有隐私保护匿名模型不能实现敏感值的个性化保护,为此,论文提出完全(α,k)-匿名模型,该模型通过设置等价类中敏感值的出现频率来实现敏感值的个性化保护.论文还提出(,αk)-聚类算法来实现各种(α,k)-匿名模型.实验表明:完全(,αk)-匿... 现有隐私保护匿名模型不能实现敏感值的个性化保护,为此,论文提出完全(α,k)-匿名模型,该模型通过设置等价类中敏感值的出现频率来实现敏感值的个性化保护.论文还提出(,αk)-聚类算法来实现各种(α,k)-匿名模型.实验表明:完全(,αk)-匿名模型能够以与其它(,αk)-匿名模型近似的信息损失量和时间代价,获得更好的隐私保护. 展开更多
关键词 (α k)-匿名模型 K-匿名 l-多样性 同质性攻击 背景知识攻击
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Electro-acupuncture regulates the cholinergic anti-inflammatory pathway in a rat model of chronic obstructive pulmonary disease 被引量:39
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作者 Xin-fang Zhang Shui-ying Xiang +5 位作者 Wen-ye Geng Wen-juan Cong Jing Lu Chuan-wei Jiang Kun Wang Zi-bing Liu 《Journal of Integrative Medicine》 CAS CSCD 2018年第6期418-426,共9页
Objective: Acupuncture has a definite therapeutic effect on chronic obstructive pulmonary disease (COPD), and the cholinergic anti-inflammatory pathway (CAP) has been shown to be involved in regula- tion of infla... Objective: Acupuncture has a definite therapeutic effect on chronic obstructive pulmonary disease (COPD), and the cholinergic anti-inflammatory pathway (CAP) has been shown to be involved in regula- tion of inflammation. In this study, we investigated whether electro-acupuncture (EA) affects the CAP in COPD,Methods: Sprague-Dawley rats were induced into COPD through exposure to cigarette smoke combined with lipopolysaccharide. EA treatment was applied at Zusanli (ST36) and Feishu (BL13) points for 30 min/d for 7 d. Seventy-two rats were randomly divided into six study groups, including normal, normal + EA, normal + α-bungarotoxin (α-BGT) (the antagonist of the nicotinic acetylcholine receptor α7 subunit (α7nAChR)) + EA, COPD, COPD + EA, and COPD + α-BGT + EA. Lung function, pathology and vagus nerve discharge were tested. The levels of acetylcholine (ACh), acetylcholinesterase (ACHE), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-ct) in bronchoalveolar lavage fluid (BALF) and lung tissue were measured by enzyme-linked immunosorbent assay. The mRNA and protein expression and immunoreac- tivity of α7nAChR and its postreceptor inflammation signal pathway, including janus kinase 2 (JAK2), sig- nal transducers and activators of transcription 3 (STAT3), nuclear factor-KB (NF-KB), were observed by quantitative reverse transcription-polymerase chain reaction, Western blot and immunohistochemistry. Results: Compared with normal rats, there were a significant decline in lung function and discharge of the vagus nerve (P 〈 0.01), a marked sign of lung inflammation and an increase of ACh, ACHE, IL-6 and TNF-α level in BALF or lung tissue (P 〈 0.05, P 〈 0.01 ) and higher expression of 0t7nAChR, JAK2, STAT3 and NF-αB (P 〈 0.05, P 〈 0.01) in the COPD rats. In rats receiving EA, the lung function and vagal discharge were enhanced (P 〈 0.01 ), lung inflammation was improved and the levels of ACh, ACHE, IL- 展开更多
关键词 Chronic obstructive pulmonary disease ELECTRO-ACUPUNCTURE α -Bungaratoxin Cholinergic anti-inflammatory pathway Vagus nerve
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α-Al_2O_3的晶体结构与价电子结构 被引量:25
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作者 谭训彦 王昕 +3 位作者 尹衍升 刘英才 张金升 孟繁琴 《中国有色金属学报》 EI CAS CSCD 北大核心 2002年第z1期18-23,共6页
对α Al2 O3 的晶体结构进行了详细的讨论 ,通过各种立体插图 ,对比分析了α Al2 O3 的菱面体晶胞和六方晶胞 ,并对每种晶胞中各种原子的排列位置进行了深入分析 ,确定了某一具体位置的O2 -或Al3 + 与其它离子之间的主要键距 ,最后根据... 对α Al2 O3 的晶体结构进行了详细的讨论 ,通过各种立体插图 ,对比分析了α Al2 O3 的菱面体晶胞和六方晶胞 ,并对每种晶胞中各种原子的排列位置进行了深入分析 ,确定了某一具体位置的O2 -或Al3 + 与其它离子之间的主要键距 ,最后根据“固体与分子经验电子理论 (EET)”计算出了α Al2 O3 晶体的价电子结构 ,并以图示的方式把主要的键及键距标示在图中 ,使能直观地看到α Al2 O3 晶体中最强键及次强键等在晶体中的方位 ,便于分析α Al2 O3 的结构与性能的相互关系。 展开更多
关键词 α -Al2O3 晶体结构 价电子结构
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Synergistic effect of a novel oxymatrine-baicalin combination against hepatitis B virus replication, a smooth muscle actin expression and typeⅠcollagen synthesis in vitro 被引量:33
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作者 Yang Cheng Jian Ping +2 位作者 Huai-Dong Xu Hai-Jun Fu Zhao-Hui Zhou 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第32期5153-5159,共7页
AIM: To study the effect of oxymatrine-baicalin combination (OB) against HBV replication in 2.2.15 cells and α smooth muscle actin ( α SMA) expression, type I, collagen synthesis in HSC-T6 cells. METHODS: The ... AIM: To study the effect of oxymatrine-baicalin combination (OB) against HBV replication in 2.2.15 cells and α smooth muscle actin ( α SMA) expression, type I, collagen synthesis in HSC-T6 cells. METHODS: The 2.2.15 cells and HSC-T6 cells were cultured and treated respectively. HBsAg and HBeAg in the culture supernatants were detected by ELISA and HBV DNA levels were determined by fluorescence quantitative PCR. Total RNA was extracted from HSC-T6 cells and reverse transcribed into cDNA. The cDNAs were amplified by PCR and the quantities were expressed in proportion to β actin. The total cellular proteins extracted from HSC-T6 cells were separated by electrophoresis. Resolved proteins were electrophoretically transferred to nitrocellulose membrane. Protein bands were revealed and the quantities were corrected by β actin. RESULTS: In the 2.2.15 cell culture system, the inhibitory rate against secretion of HBsAg and HBeAg in the OB group was significantly stronger than that in the oxymatrine group (HBsAg, P = 0.043; HBeAg, P = 0.026; respectively); HBV DNA level in the OB group was significantly lower than that in the oxymatrine group (P = 0.041). In HSC-T6 cells the mRNA and protein expression levels of α SMA in the OB group were significantly lower as compared with those in the oxymatrine group (mRNA, P = 0.013; protein, P = 0.042; respectively); The mRNA and protein expression levels of type I collagen in the OB group were significantly lower as compared with those in the oxymatrine group (mRNA, P 〈 0.01; protein, P 〈 0.01; respectively).CONCLUSION: OB combination has a better effect against HBV replication in 2.2.15 cells and is more effective against α SMA expression and type I collagen synthesis in HSC-T6 cells than oxymatrine in vitro. 展开更多
关键词 2.2.15 cells HSC-T6 cells OXYMATRINE BAICALIN Hepatitis B virus α smooth muscle actin TypeI collagen
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铕镧苯甲酸α,α′-联吡啶配合物的合成及性质研究 被引量:14
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作者 赵永亮 赵凤英 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2002年第6期987-989,共3页
在乙醇介质中合成了以Eu3+ 和La3+ 为中心体、苯甲酸和α ,α′ 联吡啶为配体的混合稀土配合物。测定了配合物的组成、研究了其紫外光谱和红外光谱。结果表明 ,配合物的组成为EuxLa1 -x(Dipy)L3·H2 O ,苯甲酸和α ,α′ 联吡啶的... 在乙醇介质中合成了以Eu3+ 和La3+ 为中心体、苯甲酸和α ,α′ 联吡啶为配体的混合稀土配合物。测定了配合物的组成、研究了其紫外光谱和红外光谱。结果表明 ,配合物的组成为EuxLa1 -x(Dipy)L3·H2 O ,苯甲酸和α ,α′ 联吡啶的紫外吸收峰在配合物中分别位移了 2~ 9nm ;苯甲酸根羧基的反对称伸缩振动和对称伸缩振动在配合物中向低波数移动 ,而α ,α′ 联吡啶的CN振动则向高波数移动。这些事实表明 ,苯甲酸和α ,α′ 联吡啶与稀土离子配位。荧光测试表明 ,用不发光的镧离子取代该系列配合物中部分铕离子 ,在一定范围内 ,可以提高三价铕的特征荧光发射强度。这一结果也表明 ,在该系列配合物中 ,不仅配体可以将吸收的能量传递给发光的铕离子 ,使其发光 ,而且不发光的镧配合物也可将其吸收的能量通过分子内能量传递给铕离子 ,增强铕的发光强度。 展开更多
关键词 配合物 合成 性质 苯甲酸 α α′-联吡啶 稀土 发光性能
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葛根素、丹参注射液、川芎嗪对MCAO大鼠血浆6-keto-PGF_(1α)、TXB_2、NO、ET的影响 被引量:16
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作者 王世军 姬广臣 +3 位作者 毛海燕 史仁华 张栋 王红海 《中药药理与临床》 CAS CSCD 1999年第4期22-24,共3页
目的:研究iv 葛根素、川芎嗪 、丹参 注射液对大脑中动 脉结扎( M C A O) 后大鼠血 浆6keto P G F1α、 T X B2 、 N O、 E T 的影响。方法:大鼠结扎大脑中动脉造成实验性脑缺血,iv 上述药物 14 ... 目的:研究iv 葛根素、川芎嗪 、丹参 注射液对大脑中动 脉结扎( M C A O) 后大鼠血 浆6keto P G F1α、 T X B2 、 N O、 E T 的影响。方法:大鼠结扎大脑中动脉造成实验性脑缺血,iv 上述药物 14 天,应用 放免法及 硝酸酶还原法测定上述指标。结果:iv 葛 根素(50 m g/ kg) 、丹参注射液(15g/kg) 、川芎嗪(20 m g/kg) 均可增加 M C A O 后6keto P G F1α与 T X B2 比例,降低血浆 E T 的含量,葛根素还可明显降低血浆 N O 的浓度。结论: 上述药物 调节脑血流量改善微循环作用,主要与其对6keto P G F1α、 T X B2 、 N O、 E T 的调节有关 。 展开更多
关键词 脑缺血 葛根素 川芎嗪丹参注射液 脑血管病 大脑中动脉阻断 6-keto-PGF1 α RZB2 NO ET
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慢性肝病肿瘤坏死因子α水平及其与发病机制的关系 被引量:30
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作者 袁爱力 罗元辉 +1 位作者 刘思德 赖卓胜 《中华内科杂志》 CAS CSCD 北大核心 1994年第10期672-674,共3页
检测外周血肿瘤坏死因子α(TNTα)水平,显示21例慢性迂延性肝炎(CPH)、42例慢性活动性肝炎(CAH)、106例肝硬化(LC)及110例原发性肝癌(PHC)之TNFα均显著高于正常对照(P<0.01)。慢性肝炎... 检测外周血肿瘤坏死因子α(TNTα)水平,显示21例慢性迂延性肝炎(CPH)、42例慢性活动性肝炎(CAH)、106例肝硬化(LC)及110例原发性肝癌(PHC)之TNFα均显著高于正常对照(P<0.01)。慢性肝炎中ALT升高及胆红素>100μmol/L者其TNFα水平显著上升。乙型肝炎病毒(HBV)合并丙型肝炎病毒(HCV)/丁型肝炎病毒(HDV)感染时TNFα水平亦显著高于单纯HBV感染。PHC患者TNFα水平与甲胎蛋白(AFP)浓度无相关性。提示TNFα参与肝脏的活动性病变过程。 展开更多
关键词 肝疾病 肿瘤坏死因子 α 病理
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Heterotrimeric G protein α subunit is involved in rice brassinosteroid response 被引量:29
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作者 Lei Wang Yun-Yuan Xu +3 位作者 Qi-Bin Ma Dan Li Zhi-Hong Xu Kang Chong 《Cell Research》 SCIE CAS CSCD 2006年第12期916-922,共7页
Heterotrimeric G proteins are known to function as messengers in numerous signal transduction pathways.The nullmutation of RGA(rice heterotrimeric G protein α subunit),which encodes the α subunit of heterotrimeric G... Heterotrimeric G proteins are known to function as messengers in numerous signal transduction pathways.The nullmutation of RGA(rice heterotrimeric G protein α subunit),which encodes the α subunit of heterotrimeric G proteinin rice,causes severe dwarfism and reduced responsiveness to gibberellic acid in rice.However,less is known aboutheterotrimeric G protein in brassinosteroid(BR)signaling,one of the well-understood phytohormone pathways.In thepresent study,we used root elongation inhibition assay,lamina inclination assay and coleoptile elongation analysis todemonstrated reduced sensitivity of dl mutant plants(caused by the null mutation of RGA)to 24-epibrassinolide(24-epiBL),which belongs to brassinosteroids and plays a wide variety of roles in plant growth and development.Moreover,RGA transcript level was decreased in 24-epiBL-treated seedlings in a dose-dependent manner.Our results show thatRGA is involved in rice brassinosteroid response,which may be beneficial to elucidate the molecular mechanisms of Gprotein signaling and provide a novel perspective to understand BR signaling in higher plants. 展开更多
关键词 heterotrimeric G protein α subunit dl mutant BR signaling RICE
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Alcohol,inflammation,and gut-liver-brain interactions in tissue damage and disease development 被引量:26
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作者 H Joe Wang Samir Zakhari M Katherine Jung 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第11期1304-1313,共10页
Chronic inflammation is often associated with alcoholrelated medical conditions. The key inducer of such inflammation, and also the best understood, is gut microflora-derived lipopolysaccharide (LPS). Alcohol can sign... Chronic inflammation is often associated with alcoholrelated medical conditions. The key inducer of such inflammation, and also the best understood, is gut microflora-derived lipopolysaccharide (LPS). Alcohol can significantly increase the translocation of LPS from the gut. In healthy individuals, the adverse effects of LPS are kept in check by the actions and interactions of multiple organs. The liver plays a central role in detoxifying LPS and producing a balanced cytokine milieu. The central nervous system contributes to anti-inflammatory regulation through neuroimmunoendocrine actions. Chronic alcohol use impairs not only gut and liver functions, but also multi-organ interactions, leading to persistent systemic inflammation and ultimately, to organ damage. The study of these interactions may provide potential new targets for therapeutic intervention. 展开更多
关键词 Chronic alcohol use Chronic inflammation Li- popolysaccharides Pro-inflammatory and anti-inflammatory cytokines Kupffer cells MONOCYTES Tumor necrosis factor α INTERLEUKIN-10 NEUROENDOCRINE Hypothalamo-pituitary-adrenal axis GLUCOCORTICOID
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有机锡氧簇合物在有机合成中的催化作用 被引量:18
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作者 吕妍 谢庆兰 《合成化学》 CAS CSCD 2001年第6期474-482,共9页
综述了以四烃基二锡氧烷 为代表的有机锡氧簇合物作为催化剂在酯交换、酯化、羰基缩醛保护和脱保护以及开环聚合等有机反应中的催化作用。化合物 的 Sn-O环具有独特的二聚层状结构 ,使其在有机合成中体现出特殊的催化活性。本文就相... 综述了以四烃基二锡氧烷 为代表的有机锡氧簇合物作为催化剂在酯交换、酯化、羰基缩醛保护和脱保护以及开环聚合等有机反应中的催化作用。化合物 的 Sn-O环具有独特的二聚层状结构 ,使其在有机合成中体现出特殊的催化活性。本文就相关反应和反应机理进行了综述。参考文献 2 展开更多
关键词 有机锡氧簇合物 四烃基二锡氧烷 催化剂 反应机理 有机合成 酯交换反应 酯化反应 α β-不饱和羰基 缩醛保护
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Changes in HIF-1α, VEGF, NGF and BDNF Levels in Cerebrospinal Fluid and TheirRelationship with Cognitive Impairment in Patients with Cerebral Infarction 被引量:24
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作者 柯贤军 章军建 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2013年第3期433-437,共5页
Summary: This study was carried out to investigate the role of intrinsic neuroprotective mechanisms in the occurrence and development of vascular cognitive impairment (VCI) with the goal of providing a target for t... Summary: This study was carried out to investigate the role of intrinsic neuroprotective mechanisms in the occurrence and development of vascular cognitive impairment (VCI) with the goal of providing a target for the treatment and prevention of VCI. Inpatients with proven cerebral infarction on cranial computed tomography (CT) were recruited as the ischemic cerebrovascular diseases (ICVD) group, and the patients with mixed stroke were excluded. In ICVD group, 12 patients were diagnosed as having VCI and served as VCI group. Inpatients undergoing surgical operation in our hospital were enrolled as control group. Double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) was employed to detect the levels of hypoxia-inducible factor 1-alpha (HIF-1α), vascular endothelial growth factor (VEGF), nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) in the cerebrospinal fluid of patients with ICVD. Associations between the levels of these factors and the Mini-Mental State Examination (MMSE) score were evaluated. In ICVD and VCI groups, the levels of HIF-1α and NGF in the cerebrospinal fluid were markedly lower than those in control group (P=-0.037 and P=0.000; P=0.023 and P=-0.005). In ICVD and VCI groups, the MMSE score was negatively related to VEGF level in the cerebrospinal fluid (r=-0.327, P=0.021; r=-0.585, P=0.046). In VCI group, HIF-1α level was correlated with NGF level (r=0.589, P=0.044). HIF-1α and NGF are involved in ischemic and hy- poxic cerebral injury. The HIF signaling pathway plays an important role in intrinsic neuroprotection. Upregulation and maintenance of HIF-1α and NGF expression may attenuate VCI. Changes in VEGF levels are related to the occurrence and development of cognitive impairment. 展开更多
关键词 ischemic cerebrovascular diseases vascular cognitive impairment cerebrospinal fluid hy- poxia inducible factor- 1 α
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室温硫化泡沫硅橡胶的研究 被引量:22
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作者 潘大海 刘梅 《有机硅材料》 CAS 2004年第3期10-12,共3页
以α ω -二羟基聚二甲基硅氧烷 (1 0 7硅橡胶 )、含氢硅油、沉淀法白炭黑为主要原料 ,制成了适合于灌封的双组分室温硫化 (RTV - 2 )泡沫硅橡胶。讨论了 1 0 7硅橡胶粘度、含氢硅油和铂催化剂用量对RTV - 2泡沫硅橡胶发泡性能、硫化性... 以α ω -二羟基聚二甲基硅氧烷 (1 0 7硅橡胶 )、含氢硅油、沉淀法白炭黑为主要原料 ,制成了适合于灌封的双组分室温硫化 (RTV - 2 )泡沫硅橡胶。讨论了 1 0 7硅橡胶粘度、含氢硅油和铂催化剂用量对RTV - 2泡沫硅橡胶发泡性能、硫化性能及阻燃性能的影响。结果表明 ,随着 1 0 7硅橡胶粘度、含氢硅油和催化剂用量的增加 ,泡沫的发泡系数增大 ,泡孔尺寸逐渐减小 ,泡孔的闭孔率增加 ,泡孔的分布趋于均匀细密、硬度降低、弹性增加 ;当 1 0 7硅橡胶粘度为 3~ 5Pa·s、含氢硅油和铂催化剂的用量分别为 3份和 5~ 8份时 ,泡沫硅橡胶的发泡系数为 2 5~ 3 0 。 展开更多
关键词 室温硫化 泡沫硅橡胶 铂催化剂 α ω-二羟基聚二甲基硅氧烷 含氢硅油
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肿瘤坏死因子α介导动脉粥样硬化发生机制的研究进展 被引量:24
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作者 周平 罗云 +3 位作者 邢娜 卢珊 孙桂波 孙晓波 《世界中医药》 CAS 2015年第8期1163-1168,共6页
动脉粥样硬化作为一种复杂的炎症性疾病,已严重威胁人类健康。肿瘤坏死因子α是一种多效性的细胞因子,可通过多种信号通路介导炎症反应。大量研究表明,肿瘤坏死因子α能够诱导血管内皮细胞、血管平滑肌细胞的损伤,诱导单核细胞的迁移并... 动脉粥样硬化作为一种复杂的炎症性疾病,已严重威胁人类健康。肿瘤坏死因子α是一种多效性的细胞因子,可通过多种信号通路介导炎症反应。大量研究表明,肿瘤坏死因子α能够诱导血管内皮细胞、血管平滑肌细胞的损伤,诱导单核细胞的迁移并与内皮细胞黏附以及泡沫细胞的形成,同时还能影响斑块的稳定性,深度参与动脉粥样硬化的形成和发展。文章就近年来肿瘤坏死因子α介导动脉粥样硬化发生机制的研究予以综述。 展开更多
关键词 肿瘤坏死因子 α 动脉粥样硬化 发生机制
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α,α-二乙酰基二硫缩烯酮和芳醛的缩合反应研究 被引量:10
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作者 艾林 刘群 +1 位作者 李晓芳 王芒 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2003年第7期1222-1224,共3页
在碱性条件下 ,α,α-二乙酰基二硫缩烯酮和芳醛的缩合反应受烷硫基的影响 .α,α-二乙酰基二苄硫缩烯酮 1和芳醛 3缩合生成单面缩合脱乙酰基产物α-肉桂酰基二苄硫缩烯酮 4 ;α,α-二乙酰基环二硫缩烯酮 2和芳醛 3缩合生成双面缩合产物... 在碱性条件下 ,α,α-二乙酰基二硫缩烯酮和芳醛的缩合反应受烷硫基的影响 .α,α-二乙酰基二苄硫缩烯酮 1和芳醛 3缩合生成单面缩合脱乙酰基产物α-肉桂酰基二苄硫缩烯酮 4 ;α,α-二乙酰基环二硫缩烯酮 2和芳醛 3缩合生成双面缩合产物α,α-二肉桂酰基环二硫缩烯酮 5 . 展开更多
关键词 α α-二乙酰基二硫缩烯酮 芳醛 缩合反应 α-羟基二硫缩烯酮
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A refinement about estimation of expansion coefficients for normalized biholomorphic mappings 被引量:20
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作者 LIU Taishun LIU Xiaosong 《Science China Mathematics》 SCIE 2005年第7期865-879,共15页
A refining estimation of homogeneous expansion for / is discussed, where f belongs to a subclass of all normalized biholomorphic mappings defined on the unit polydisk in Cn or the unit ball in complex Banach spaces, a... A refining estimation of homogeneous expansion for / is discussed, where f belongs to a subclass of all normalized biholomorphic mappings defined on the unit polydisk in Cn or the unit ball in complex Banach spaces, and x = 0 is a zero of order k+1 of f(x)-x. Moreover, an estimation of homogeneous expansion for subordinate mappings defined on the unit ball in complex Banach spaces is also given. 展开更多
关键词 de Branges theorem refining estimation of homogeneous expansion almost starlike mapping of order a starlike mapping of order a subordinate mapping.
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有氧运动抑制心力衰竭大鼠心脏脂质沉积:AMPK-PPARα信号通路的作用 被引量:20
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作者 赛庆彬 马延超 朱荣 《中国运动医学杂志》 CAS CSCD 北大核心 2012年第12期1081-1086,1108,共7页
目的:观察8周有氧运动对心力衰竭大鼠心脏脂质沉积和心功能的影响,探讨AMP激活的蛋白激酶(AMPK)—过氧化物酶体增殖物激活受体α(PPARα)信号通路在其中的作用机制。方法:结扎大鼠冠状动脉建立心梗后心衰模型,术后4周随机分为假手术安静... 目的:观察8周有氧运动对心力衰竭大鼠心脏脂质沉积和心功能的影响,探讨AMP激活的蛋白激酶(AMPK)—过氧化物酶体增殖物激活受体α(PPARα)信号通路在其中的作用机制。方法:结扎大鼠冠状动脉建立心梗后心衰模型,术后4周随机分为假手术安静组(Sham组)、心梗安静组(MI-Sed组)和心梗运动组(MI-Ex组)。MI-Ex组进行为期8周的跑台运动,Sham组和MI-Sed组保持安静状态。实验结束后,左心室导管法测定血流动力学参数包括左心室收缩期压力(LVSP)、左心室舒张末期压力(LVEDP)、左心室压力最大上升速率(+dp/dtmax)和左室压力最大下降速率(-dp/dtmax);比色法测定心肌和血浆游离脂肪酸(FFA)水平;氧化酶法测定心肌甘油三酯含量;实时荧光定量PCR检测心肌PPARα和肉碱棕榈酰转移酶-1(CPT-1)mRNA水平;Western blot法检测心肌总AMPKα、磷酸化的AMPKα(p-AMPKα)、PPARα和CPT-1蛋白表达水平。结果:与Sham组比较,MI-Sed组LVSP、±dp/dtmax显著性下降(均为P<0.01),LVEDP则显著性升高(P<0.01);血浆FFA、心肌FFA和甘油三酯水平升高(均为P<0.01);心肌PPARα和CPT-1 mRNA及蛋白显著降低(均为P<0.01),p-AMPKα蛋白显著升高(P<0.05)。与MI-Sed组比较,MI-Ex组LVSP、±dp/dtmax显著性升高(均为P<0.01),LVEDP则显著性下降(P<0.01);血浆FFA、心肌FFA和甘油三酯水平显著降低(均为P<0.01);心肌PPARα和CPT-1 mRNA和蛋白以及p-AMPKα蛋白水平均显著性升高(均为P<0.01)。结论:长期有氧运动活化AMPK-PPARα信号通路,上调CPT-1表达,促进心肌对FFA的氧化利用,从而减轻HF后心脏脂质过度沉积、改善脂毒性心脏异常并提高心功能。 展开更多
关键词 有氧运动 心力衰竭 脂质沉积 AMP激活的蛋白激酶 过氧化物酶体增殖物激活受体 α 肉碱棕榈酰转移酶-1
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研磨法合成α,β-不饱和酮 被引量:14
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作者 王书香 李记太 王振华 《有机化学》 SCIE CAS CSCD 北大核心 2004年第4期447-449,354,共4页
将苯乙酮、芳香醛与KF Al2 O3 置于研钵中 ,在无溶剂条件下 ,室温研磨 5min后放置一定时间 ,得到收率 94%~ 98%的α ,β 不饱和酮 .该法反应条件温和 ,操作简便 ,KF Al2 O3
关键词 芳香醛 苯乙酮 α Β-不饱和酮 合成 研磨
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