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Synthesis and antitumor activities of novel 1,4-substituted phthalazine derivatives 被引量:2
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作者 Shu Lan Zhang Ya Jing Liu Yan Fang Zhao Qiu Ting Guo Ping Gong 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第9期1071-1074,共4页
A series of 1,4-substituted phthalazine derivatives were designed and synthesized.All the prepared compounds were screened for their cytotoxic activities against A549.HT-29 and MDA-MB-231 cell lines in vitro.Among the... A series of 1,4-substituted phthalazine derivatives were designed and synthesized.All the prepared compounds were screened for their cytotoxic activities against A549.HT-29 and MDA-MB-231 cell lines in vitro.Among them,compounds 7a-7h showed excellent selectivity for MDA-MB-231 cell line with IC50 values from 1 nmol/L to 0.92μmol/L.A preliminary SAR study of these derivatives was performed. 展开更多
关键词 1 4-substituted phthalazine SYNTHESIS CYTOTOXICITY
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Facile access to chiral 4-substituted chromanes through Rh-catalyzed asymmetric hydrogenation
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作者 Lin Tao Qingyang Zhao +1 位作者 Xumu Zhang Xiu-Qin Dong 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第7期1859-1862,共4页
Rh/ZhaoPhos-catalyzed asymmetric hydroge nation of a series of(E)-2-(chro man-4-ylidene)acetates was successfully developed to prepare various chiral 4-substituted chromanes with high yields and excellent enantioselec... Rh/ZhaoPhos-catalyzed asymmetric hydroge nation of a series of(E)-2-(chro man-4-ylidene)acetates was successfully developed to prepare various chiral 4-substituted chromanes with high yields and excellent enantioselectivities(up to 99%yield,98%ee).Moreover,the gram-scale hydrogenation could be performed well in the presence of 0.02 mol%catalyst loading(TON=5000),the hydrogenation product was easily converted to access other important compounds,which demonstrated the synthetic utility of this asymmetric catalytic methodology. 展开更多
关键词 Chiral 4-substituted chromanes Asymmetric hydrogenation Excellent enantioselectivity Gram-scale synthesis Bisphosphine-thiourea ligand
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Synthesis of 3 or 4-Substituted Pyridine-2, 6-Dicarboxylic Acid Derivatives
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作者 尹显洪 杨满芽 +2 位作者 史华红 陈小明 古练权 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期395-395,共1页
关键词 CDA Synthesis of 3 or 4-substituted Pyridine-2 DPA Dicarboxylic Acid Derivatives
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SYNTHESIS OF 4-SUBSTITUTED (OR 4-SPIRO) 3-OXABICYCLO[3.1.0]HEXAN-2-ONE
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作者 Jie You XUE, Shi Xiong TANG, Ai Bin SUN, Fan WU, Li Xin QIAO, Yu Rong CAO, Xiao Lan WANG Department of Chemistry, Nankai University, Tianjin 300071 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第11期837-838,共2页
Cyclopropanedicarboxylic anhydride can be converted to 4-substituted (or 4-spiro-)3-oxabicyclo[3.1.0]hexan-2-one by addition of Grignard (or α,ω-di-Crignard) reagents in ether or tetrahydrofuran solution.
关键词 OXABICYCLO[3.1.0]HEXAN-2-ONE SYNTHESIS OF 4-substituted OR 4-SPIRO
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Stereoselective Synthesis of 2-Chloro-4-Substituted-phenyl-5,5-Dimethyl-1,3,2-Dioxaphosphorinan-2-(Thi)ones 被引量:1
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作者 Rui Lian SHAO Guang Fu YANG +1 位作者 Wei Shi MIAO Min Hua YANG(National Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin, 300071) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第10期855-858,共4页
The stereoselective synthesis of 2-chloro-4-substituted-phenyl-5,5-dimethyl-1,3,2-dioxaphosphorinan-2-(thi)ones is described. Only single trans-isomers were obtained when 1-substituted-phenyl-2,2-dimethyl-1,3-propaned... The stereoselective synthesis of 2-chloro-4-substituted-phenyl-5,5-dimethyl-1,3,2-dioxaphosphorinan-2-(thi)ones is described. Only single trans-isomers were obtained when 1-substituted-phenyl-2,2-dimethyl-1,3-propanediols (1) reacted with POCl3. But the stereoselectivity of cyclization reaction between (1) and PSCl3 depended greatly upon the reaction condition. The configurational assignments and the ratio of cis-/trans- diastereoisomers of the products were performed on the basis of (HNMR)-H-1, (PNMR)-P-31 and IR spectra and confirmed by X-ray diffraction analyses. 展开更多
关键词 HNMR Cl Stereoselective Synthesis of 2-Chloro-4-substituted-phenyl-5 5-Dimethyl-1 3 2-Dioxaphosphorinan-2 Thi)ones
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SYNTHESES AND SUBSTITUENT EFFECTS ON 4-^(13)C-NMR OF BIOACTIVE 4-SUBSTITUTED-2,6,7-TRIOXA-1-PHOSPHABICYCLO[2.2.2]OCTANE-1-OXIDES
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作者 Wen Xiang HU Liu Hong YUN Institute of Pharmacology and Toxicology,Academy of Military Medical Sciences,Beijing 100850 Ji Sheng CHEN Hua Tang XU Shui Sheng JIA Xuan Long XU Beijing Institute of Pharmaceutical Chemistry,No.401,Po Box 1044,Beijing 102205 Cheng Ye YUAN Shu Sen LI Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,Shanghai 200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第12期959-962,共4页
Ten 4-substituted bicyclic phosphates were synthesized and their ^(13)C-NMR were also determined.A good relationship was observed between 4-^(13)C chemical shift and Taft σ_X induc- tive paramenters.Substituent effec... Ten 4-substituted bicyclic phosphates were synthesized and their ^(13)C-NMR were also determined.A good relationship was observed between 4-^(13)C chemical shift and Taft σ_X induc- tive paramenters.Substituent effects on ~3J_(P-C) coupling constant were studied. 展开更多
关键词 NMR SYNTHESES AND SUBSTITUENT EFFECTS ON 4 C-NMR OF BIOACTIVE 4-substituted-2 6 7-TRIOXA-1-PHOSPHABICYCLO[2.2.2]OCTANE-1-OXIDES
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Syntheses,Structures and Luminescent Properties of Cd(Ⅱ)/Zn(Ⅱ) Coordination Polymers Based on the Flexible 4-Substituted Bis(1,2,4-triazole) Ligand 被引量:3
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作者 彭艳芬 刘天宝 吴秋艳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第7期1156-1163,共8页
Two new cadmium(II) and zinc(II) coordination polymers, {[Cd(btre)0.5- (mip)(H2O)2]·H2O}n (1) and [Zn(btre)(mip)]n (2), were synthesized at room temperature condition and characterized by IR spe... Two new cadmium(II) and zinc(II) coordination polymers, {[Cd(btre)0.5- (mip)(H2O)2]·H2O}n (1) and [Zn(btre)(mip)]n (2), were synthesized at room temperature condition and characterized by IR spectra, elemental analyses, single-crystal and powder X-ray diffractions (btre = 1,2-bis(1,2,4-triazol-4-yl)ethane, H2mip = 5-methyl-1,3-benzenedicarboxylic acid). Complex 1 belongs to the triclinic system, P space group, with a = 8.9830(6), b = 10.0579(6), c = 10.2479(9) , α = 98.837(6), β = 115.975(8), γ = 106.370(6)°, V = 756.30(11) 3 and Z = 2; complex 2 crystallizes in monoclinic, space group P21/c, with a = 7.0332(3), b = 14.9947(7), c = 15.9689(7) ?, β = 97.1170(10)°, V = 1671.12(13) ?3 and Z = 4. Compounds 1 and 2 based on the same N/O-donor ligands show different structures. The one-dimensional chains of 1 are further linked by hydrogen bonding and π-π interactions to yield a three-dimensional supramolecular structure. The two-dimensional (6,3) networks of 2 are further extended into a 3D framework via π-π interactions. Thermal stabilities and luminescence of 1 and 2 were investigated. 展开更多
关键词 1 2-bis(1 2 4-triazol-4-yl)ethane 2D (6 3) network luminescence coordination polymer
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Synthesis and anti-TMV activity of novel N-(3-alkyl-1H-pyrazol-4-yl)-3-alkyl-4-substituted-1H-pyrazole-5-carboxamides 被引量:3
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作者 Da Qiang Zhang Gao Fei Xu +3 位作者 Zhi Jin Fan Dao Quan Wang Xin Ling Yang De Kai Yuan 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第6期669-672,共4页
In order to investigate the biological activity of novel bis-pyrazole compounds, a series of N-(3-alkyl-5-(N-methylcarbamyl)- 1H-pyrazol-4-yl)-3-alkyl-4-substituted-lH-pyrazole-5-carboxamides were designed and syn... In order to investigate the biological activity of novel bis-pyrazole compounds, a series of N-(3-alkyl-5-(N-methylcarbamyl)- 1H-pyrazol-4-yl)-3-alkyl-4-substituted-lH-pyrazole-5-carboxamides were designed and synthesized with ethyl 3-alkyl-lH-pyr- azole-5-carboxylate 1 as starting materials. N-Methyl-3-alkyl-4-amino-lH-pyrazole-5-carboxamides 6 were obtained from 1 via 5 steps. 3-Alkyl-4-substitued-lH-pyrazole-5-carboxyl chlorides 4a, 4b, lla, llb, llc or 12 were also obtained from 1 via several steps. Target compounds 7a-Tg were obtained after the reaction of 6 with the above 1H-pyrazole-5-carboxyl chlorides. Preliminary bioassay showed some compounds possessing good inactivation effect against TMV (tobacco mosaic virus). Compound 7a showed higher activity superior to ningnanmycin at a concentration of 5.0 × 10^-4 g/mE and equal activity at 1.0 × 10^-4 g/mE; 7b and 7c showed equal activity to virazole both at concentrations of 5.0 × 10^-4 g/mE and 1.0 × 10^-4 g/mL. 展开更多
关键词 Bis-pyrazole compounds 3-Alkyl-4-amino-lH-pyrazole-5-carboxamides 3-Alkyl-lH-pyrazole-5-carboxyl chlorides Inactivationeffect TMV
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Efficient synthesis of 4-substituted pyrazole via microwave-promoted Suzuki cross-coupling reaction 被引量:1
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作者 Hua Cheng Qiong-You Wu +1 位作者 Fan Han Guang-Fu Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第5期705-709,共5页
Pyrazoles and their derivatives are important heterocycles found in nature and present in numerous bioactive compounds.In contrast to 3 or 5-aryl pyrazole,the preparation of 4-aryl pyrazole is fairly rare.Utilizing mi... Pyrazoles and their derivatives are important heterocycles found in nature and present in numerous bioactive compounds.In contrast to 3 or 5-aryl pyrazole,the preparation of 4-aryl pyrazole is fairly rare.Utilizing microwave irradiation,the synthesis of 4-substituted-arylpyrazole via Suzuki cross-coupling has been developed with a wide range of substrates.The remarkable advantages of this method are mild reaction conditions,simple operation,high yield,and short reaction time.Product structures were identified by MS 1H NMR 13C NMR,and elemental analysis. 展开更多
关键词 4-Aryl pyrazoles Suzuki cross-coupling reactions 4-Iodo-1-methyl-1H-pyrazole Microwave irradiation
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Syntheses, Crystal Structures, and Fluorescence Properties of Two 2D→2D Coordination Polymers Based on the Flexible 4-Substituted Bis(1,2,4-triazole) Ligand 被引量:1
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作者 PENG Yanfen LIU Tianbao WU Qiuyan 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2019年第1期8-14,共7页
Two new 2 D → 2 D zinc(II) coordination polymers, [Zn(btre)0.5(nbdc)(H2 O)]n(1) and {[Zn(btre)0.5(Me Oip)(H2 O)2]·H2 O}n(2)(btre = 1,2-bis(1,2,4-triazol-4-yl)ethane, nbdc=3-nitro-1, 2-benzenedicarboxylate, Me Oi... Two new 2 D → 2 D zinc(II) coordination polymers, [Zn(btre)0.5(nbdc)(H2 O)]n(1) and {[Zn(btre)0.5(Me Oip)(H2 O)2]·H2 O}n(2)(btre = 1,2-bis(1,2,4-triazol-4-yl)ethane, nbdc=3-nitro-1, 2-benzenedicarboxylate, Me Oip=4-methoxybenzene-1, 3-dicarboxylate) were synthesized at room temperature condition and characterized by IR spectra, elemental analyses, single-crystal and powder X-ray diffractions. Three sets of equivalent 2 D(6, 3) networks parallel polycatenated with each other to give a 2 D → 2 D network in 1 and 2. There are strong π-π interactions and hydrogen bonding interactions between adjacent parallel polycatenated 2 D(6, 3) network in 1. Only hydrogen bonding interactions exist in 2. Thermal stabilities and luminescence of 1 and 2 were investigated. 展开更多
关键词 3-fold INTERPENETRATION 1 2-bis(1 2 4-triazol-4-yl)ethane 2D(6 3)network luminescence
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Stabilizing the solid-solution sodium storage in Cr-substituted Na_(3)V_(2)(PO_(4))_(3) cathode for aqueous sodium-ion batteries with long-term stability 被引量:1
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作者 Qinyan Jian Tinghong Gao +4 位作者 Wensheng Yang Xinhai Wang Lishan He Jiarui Liu Yunjun Ruan 《Journal of Energy Chemistry》 2025年第6期797-805,I0016,共10页
Aqueous sodium-ion batteries(ASIBs) offer significant advantages for energy storage on a large scale,attributed to their economical cost,secure operatio n,and eco-friend ly natu re.Among the leading cathode materials ... Aqueous sodium-ion batteries(ASIBs) offer significant advantages for energy storage on a large scale,attributed to their economical cost,secure operatio n,and eco-friend ly natu re.Among the leading cathode materials for ASIBs,Na_(3)V_(2)(PO_(4))_(3)(NVP) exhibits excellent structural stability and a high Na+diffusion coefficient,making it a promising option.However,the high solubility of vanadium-based materials in aqueous electrolytes engenders suboptimal cycling stability for Na_(3)V_(2)(PO_(4))_(3),constraining its application in ASIBs.Herein,the Cr-substituted Na_(3)V_(1.3)Cr_(0.7)(PO_(4))3@C(NV_(1.3)Cr_(0.7)P) cathode material was synthesized via a simple sol-gel method.It is found that Cr substitution reduces the cell parameters of NV_(1.3)Cr_(0.7)P,effectively reinforcing the crystal structure.Furthermore,NV_(1.3)Cr_(0.7)P alters the Na^(+)insertion/extraction mechanism,transforming the typical two-phase reaction between Na_(1)V_(2)(PO_(4))_(3)and Na_(3)V_(2)(PO_(4))3into continuous solid-solution reactions with stable intermediates.The Cr substitution diminishes the sodium-ion diffusion energy barrier in NV_(1.3)Cr_(0.7)P,leading to smoother Na+insertion and extraction processes.Consequently,NV_(1.3)Cr_(0.7)P exhibits impressive cycling stability,retaining 74.8% of its capacity after 5,000 cycles at a current density of 5 A g^(-1),along with an outstanding rate performance of 79,2% at 10 A g^(-1).This work elucidates the stable Na^(+)insertion/extraction processes in Cr-substituted NV_(1.3)Cr_(0.7)P,offering insights into the application of vanadium-based materials in aqueous sodium-ion batteries. 展开更多
关键词 Na_(3)V_(2)(PO_(4))_(3) Cr substitution Insertion/extraction mechanism Long-term cycling stability Aqueous sodium-ion battery
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Decomposition of a β-O-4 lignin model compound over solid Cs-substituted polyoxometalates in anhydrous ethanol: acidity or redox property dependence? 被引量:1
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作者 吴学众 焦文千 +4 位作者 李秉正 黎演明 张亚红 王全瑞 唐颐 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第7期1216-1228,共13页
Production o f aromatics from lignin has attracted much attention. Because of the coexistence of C-O and C-C bonds and their complex combinations in the lignin macromolecular network, a plausible roadmap for de... Production o f aromatics from lignin has attracted much attention. Because of the coexistence of C-O and C-C bonds and their complex combinations in the lignin macromolecular network, a plausible roadmap for developing a lignin catalytic decomposition process could be developed by exploring the transformation mechanisms of various model compounds. Herein, decomposition of a lignin model compound, 2-phenoxyacetophenone (2-PAP), was investigated over several ce-sium-exchanged polyoxometalate (Cs-POM) catalysts. Decomposition of 2-PAP can follow two dif-ferent mechanisms: an active hydrogen transfer mechanism or an oxonium cation mechanism. The mechanism for most reactions depends on the competition between the acidity and redox proper-ties of the catalysts. The catalysts of POMs perform the following functions: promoting active hy-drogen liberated from ethanol and causing formation of and then temporarily stabilizing oxonium cations from 2-PAP. The use of Cs-PMo, which with strong redox ability, enhances hydrogen libera-tion and promotes liberated hydrogen transfer to the reaction intermediates. As a consequence, complete conversion of 2-PAP (〉99%) with excellent selectivities to the desired products (98.6% for phenol and 91.1% for acetophenone) can be achieved. 展开更多
关键词 Lignin model compound β-O-4 ether bond POLYOXOMETALATE Hydrogen transfer mechanism Oxonium cation mechanism Anhydrous ethanol
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防晒剂4-甲基苄亚基樟脑的安全评价及其监管情况
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作者 塔娜 朵慧 +3 位作者 张凤兰 余振喜 李波 苏哲 《日用化学工业(中英文)》 北大核心 2026年第2期245-251,共7页
文章旨在系统梳理4-甲基苄亚基樟脑的相关研究数据,对该成分作为化妆品防晒剂的安全性进行全面评估,为其在我国的使用和监管提供科学依据。通过文献调研,从理化特性、市场应用情况、人体吸收代谢机制以及安全性等多个维度对该物质展开... 文章旨在系统梳理4-甲基苄亚基樟脑的相关研究数据,对该成分作为化妆品防晒剂的安全性进行全面评估,为其在我国的使用和监管提供科学依据。通过文献调研,从理化特性、市场应用情况、人体吸收代谢机制以及安全性等多个维度对该物质展开研究。同时,回顾欧盟消费者安全科学委员会近二十年的评估历程与态度,对欧盟、美国、加拿大、澳大利亚、日本、东盟等国家(地区)的监管现状进行总结分析。经研究发现,体内实验数据表明4-甲基苄亚基樟脑对甲状腺系统可能存在一定影响,且有相关证据显示其具有潜在的内分泌干扰特性。尽管4-甲基苄亚基樟脑在国内化妆品市场中的使用频率呈现下降趋势,但相较于欧盟市场,其使用仍较为广泛,存在一定安全风险。因此,建议监管部门对该成分的安全性进行重新评估,并在此基础上为其制定科学合理的使用限量,保障公众用妆安全。 展开更多
关键词 4-甲基苄亚基樟脑 防晒剂 安全评价 监管
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基于TLR-4/MyD88/NF-κB信号通路探究温针灸干预膝骨关节炎的作用机制
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作者 王树东 董宝强 +5 位作者 盛泽伟 胡哲 于冬冬 王列 丁学峰 薛亚楠 《中华中医药学刊》 北大核心 2026年第2期24-27,I0008-I0012,共9页
目的基于Toll样受体-4(Toll-like receptors 4,TLR-4)/髓样分化因子88(Myeloid differentiation factor 88,MyD88)/核转录因子-κB(Nuclear transcription factor-kappa B,NF-κB)信号通路观察温针灸对膝骨关节炎(Knee osteoarthritis,K... 目的基于Toll样受体-4(Toll-like receptors 4,TLR-4)/髓样分化因子88(Myeloid differentiation factor 88,MyD88)/核转录因子-κB(Nuclear transcription factor-kappa B,NF-κB)信号通路观察温针灸对膝骨关节炎(Knee osteoarthritis,KOA)家兔模型的调控作用,探讨温针灸治疗膝骨关节炎的作用机制。方法健康大耳白兔40只,随机分为空白组、模型组、温针灸组、西药组,每组10只,以改良Hulth法建立膝骨关节炎模型,经4周干预后,随机处死两只,病理检查出现关节软骨表面不平整、炎性细胞浸润等改变即表明造模成功。采用HE染色法观察家兔膝关节形态学变化并进行光镜软骨检测评价标准(Mankin score,Mankin’s)评分;采用免疫组化法观察家兔膝关节软骨组织TLR-4、MyD88、NF-κB的表达,并进行半定量分析;采用酶联免疫吸附(Enzyme-linked immunosorbent assay,ELISA)法检测家兔血清中白细胞介素-6(Interleukin-6,IL-6)、白细胞介素-1β(Interleukin-1β,IL-1β)、肿瘤坏死因子-α(Tumor necrosis factor-α,TNF-α)的含量;采用Wes全自动蛋白质印迹定量分析系统检测软骨组织TLR-4、MyD88、NF-κB的蛋白表达水平。结果HE染色可见空白组家兔膝关节软骨组织平整,无任何病理变化。模型组软骨组织表面粗糙,软骨细胞呈簇状堆积或减少。温针灸组以及西药组软骨组织表面欠平整,少量裂隙,伴有少量炎性细胞浸润。与空白组相比,模型组血清中IL-6、IL-1β、TNF-α含量显著升高(P<0.05),与模型组相比,温针灸组和西药组血清中IL-6、IL-1β、TNF-α含量显著下降(P<0.05);与空白组相比,模型组软骨组织TLR-4、MyD88、NF-κB蛋白表达显著升高(P<0.05),与模型组相比,温针灸组和西药组软骨组织TLR-4、MyD88、NF-κB蛋白表达显著下降(P<0.05),且温针灸组效果更为显著。结论温针灸可以通过抑制TLR-4/MyD88/NF-κB信号通路被激活,减少下游IL-6、IL-1β、TNF-α的含量以缓解炎症反应,延缓病程进展,达到治疗KOA的目的,并能够对软骨组织起到一定程度的修复作用。 展开更多
关键词 膝骨关节炎 温针灸 炎症反应 TLR-4 MYD88 NF-ΚB
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视黄醇结合蛋白4荧光免疫层析检测技术的建立与应用研究
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作者 郑登滋 叶青 +3 位作者 张珠平 鄢雪梨 林菊珊 黄仁杰 《中国免疫学杂志》 北大核心 2026年第1期186-190,共5页
目的:建立血清视黄醇结合蛋白4(RBP4)的荧光免疫层析快速检测方法,并将其用于心血管疾病诊断研究。方法:采用双抗体夹心原理制备荧光免疫层析试纸条,系统评价线性范围、精密度、准确度、灵敏度、特异性。检测分析48例高血压样本、29例... 目的:建立血清视黄醇结合蛋白4(RBP4)的荧光免疫层析快速检测方法,并将其用于心血管疾病诊断研究。方法:采用双抗体夹心原理制备荧光免疫层析试纸条,系统评价线性范围、精密度、准确度、灵敏度、特异性。检测分析48例高血压样本、29例脑梗死样本及20例健康样本血清RBP4水平与心血管疾病相关性,并评估其诊断效能。结果:该方法对血清中RBP4的线性范围37.5~600 ng/mL,批内变异系数均<12%,批间变异系数均<13%,平均回收率95.6%,灵敏度为0.44 ng/mL,与含胆红素、甘油三酯和血红蛋白的干扰样本无明显交叉反应。相关性分析显示高血压和脑梗死患者血清RBP4水平高于健康对照,血清RBP4水平与高血压和脑梗死具有良好的相关性。ROC曲线分析显示,血清RBP4水平从健康人群中鉴别诊断高血压和脑梗死的AUC分别为0.914和0.850,提示血清RBP4水平诊断高血压的效能优于脑梗死。结论:建立了定量检测RBP4的荧光免疫层析法,有望为心血管疾病中高血压和脑梗死的早期筛查提供一种便捷的检测手段。 展开更多
关键词 视黄醇结合蛋白4 荧光免疫层析 心血管疾病
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种子休眠基因Sdr4的生物信息学分析与分子标记开发和应用
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作者 黄奇娜 姜鸿瑞 +3 位作者 杨婕 于坤宇 杨长登 梁燕 《中国水稻科学》 北大核心 2026年第1期61-71,共11页
【目的】水稻收获前穗发芽严重制约产量与品质形成,该性状主要受种子休眠基因调控。解析种子休眠分子机制对改良水稻穗萌抗性具有重要理论价值与育种意义。【方法】综合运用生物信息学分析、分子标记开发及标记辅助选择技术,系统解析种... 【目的】水稻收获前穗发芽严重制约产量与品质形成,该性状主要受种子休眠基因调控。解析种子休眠分子机制对改良水稻穗萌抗性具有重要理论价值与育种意义。【方法】综合运用生物信息学分析、分子标记开发及标记辅助选择技术,系统解析种子休眠基因Sdr4(Seed dormancy 4)的生物学功能,探究其分子标记在多基因型种质改良中的应用潜力。【结果】Sdr4启动子区含TATA-box等核心元件及ABA响应元件等多种顺式作用元件,其编码蛋白为低稳定性疏水蛋白(101~150氨基酸区段磷酸化修饰占比25.93%),三级结构以α-螺旋(15.50%)、β-折叠(15.50%)和无规则卷曲(66.37%)为主。3K单倍型数据库与AlphaFold分析表明Sdr4基因具有6种功能性突变的单倍型,且在强休眠种质Kasalath与弱休眠种质日本晴(Nipponbare)的Sdr4氨基酸序列存在多个位点差异。系统发育分析显示Sdr4在非洲栽培稻(Oryza glaberrima)与沼生菰(Zizania palustris)中具有高度保守性。通过Kasalath与日本晴的Sdr4等位变异,开发了Sdr4-KF/KR与Sdr4-PF/PR两对功能标记,可精准区分种子休眠强度。基于25个水稻品种的分子检测筛选出休眠性显著差异的种质,并利用上述标记成功创制了强休眠型中组18改良系。【结论】Sdr4通过调控种子休眠深度影响水稻穗萌抗性。分子标记筛选表明20个主栽品种均呈种子弱休眠表型,利用Sdr4特异性标记选育的K17与K88新品系具有显著穗萌抗性。本研究为Sdr4功能解析及水稻抗穗萌分子育种提供了理论支撑与技术储备。 展开更多
关键词 穗发芽 Sdr4 水稻 生物信息学 分子标记辅助选择
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仿木年轮结构Si_(3)N_(4)/Ni和316配副在海洋环境中的摩擦磨损性能研究
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作者 陈威 王朝 +4 位作者 周奥 李耶童 赵文卓 张建军 杨勇强 《陕西科技大学学报》 北大核心 2026年第1期152-160,共9页
本论文系统研究了仿木年轮Si_(3)N_(4)/Ni复合材料在海水中的摩擦磨损性能.在本研究中,利用热压烧结工艺制备仿木年轮的Si_(3)N_(4)/Ni复合材料,采用端面磨损试验机研究Si_(3)N_(4)/Ni复合材料与316不锈钢配副在人工海水环境中的摩擦磨... 本论文系统研究了仿木年轮Si_(3)N_(4)/Ni复合材料在海水中的摩擦磨损性能.在本研究中,利用热压烧结工艺制备仿木年轮的Si_(3)N_(4)/Ni复合材料,采用端面磨损试验机研究Si_(3)N_(4)/Ni复合材料与316不锈钢配副在人工海水环境中的摩擦磨损性能,利用扫描电子显微镜(SEM)观察与分析摩擦副表面的磨损形貌,采用EDS能谱仪和拉曼光谱来定性分析磨损面的表面元素与物质分布.结果表明,随着滑动速度增大,纯氮化硅和Si_(3)N_(4)/Ni复合材料与316不锈钢配副的摩擦系数均有所增大,在相同速度下,Si_(3)N_(4)/Ni复合材料与316配副表现出较好的摩擦磨损性能.当滑动速度为100 r/min时,Si_(3)N_(4)/Ni-316摩擦副表现出最优的摩擦学性能,摩擦系数为0.45,复合材料销磨损率为1.503×10^(-6)mm^(3)/Nm,金属盘磨损率为1.03×10^(-4)mm^(3)/Nm.Si_(3)N_(4)/Ni复合材料表现出相对较好的摩擦学性能,这主要归因于在复合材料摩擦表面发生了摩擦化学反应,生成硅胶(SiO_(2))和Ni_(2)SiO_(4)等物质,起到了减摩与润滑作用. 展开更多
关键词 Si_(3)N_(4)复合陶瓷 海水环境 摩擦磨损
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ACTN4、FOXQ1与子宫颈癌患者临床病理特征的关系及在预后评估的应用价值
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作者 马会 舒丽莎 +3 位作者 孙丽佳 殷晓霞 杨博 陈辛未 《中国妇产科临床杂志》 北大核心 2026年第1期11-14,共4页
目的探讨α-辅肌动蛋白4(ACTN4)、叉头框转录因子Q1(FOXQ1)与子宫颈癌患者临床病理特征及预后的关系。方法回顾性分析2017年1月至2020年1月在河北北方学院附属第一医院接受治疗的100例子宫颈癌患者的临床资料,采集其癌组织及经病理证实... 目的探讨α-辅肌动蛋白4(ACTN4)、叉头框转录因子Q1(FOXQ1)与子宫颈癌患者临床病理特征及预后的关系。方法回顾性分析2017年1月至2020年1月在河北北方学院附属第一医院接受治疗的100例子宫颈癌患者的临床资料,采集其癌组织及经病理证实无癌浸润的癌旁组织。采用免疫组化检测蛋白表达,分析其与临床病理参数的相关性;通过Kaplan-Meier、Cox回归及受试者工作特征曲线(ROC)评估两指标对患者预后的预测价值。结果ACTN4和FOXQ1在癌组织中的表达均上调(均P<0.05)。ACTN4与FOXQ1高表达组5年总生存率较低(均P<0.05),且与FIGO分期晚、低分化、深浸润及淋巴结转移独立相关(均P<0.05)。两者联合预测5年生存的AUC为0.905,灵敏度92.35%,特异度86.70%。结论ACTN4和FOXQ1高表达与子宫颈癌不良预后密切相关,可作为独立预后标志物,联合检测有助于提升预后评估效能。 展开更多
关键词 α-辅肌动蛋白4 叉头框转录因子Q1 子宫颈癌 病理特征 预后
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高良姜素调节TLR4/MD2信号通路对脑出血大鼠神经炎症的影响
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作者 曾理 张作军 +1 位作者 雷雨广 崔冬玲 《中国免疫学杂志》 北大核心 2026年第2期290-295,共6页
目的:探讨高良姜素(Gal)调节Toll样受体4(TLR4)/髓样分化蛋白-2(MD2)信号通路对脑出血大鼠神经炎症的影响。方法:SD大鼠随机分为正常组、脑出血组、Gal低剂量(Gal-L)组、Gal中剂量(Gal-M)组、Gal高剂量(Gal-H)组、Gal-H+TLR4激活剂(RS09... 目的:探讨高良姜素(Gal)调节Toll样受体4(TLR4)/髓样分化蛋白-2(MD2)信号通路对脑出血大鼠神经炎症的影响。方法:SD大鼠随机分为正常组、脑出血组、Gal低剂量(Gal-L)组、Gal中剂量(Gal-M)组、Gal高剂量(Gal-H)组、Gal-H+TLR4激活剂(RS09)组,每组18只。除正常组外,其他组大鼠均构建脑出血模型。造模成功后给药,1次/d,持续2周。检测大鼠神经功能损伤评分和脑含水量;HE染色检测血肿周围脑组织病理变化;免疫荧光染色检测血肿周围脑组织Iba-1和iNOS、Iba-1和CD206共表达情况;ELISA检测血肿周围脑组织IL-10、精氨酸酶1(Arg-1)、TNF-α、IL-1β水平;Western blot检测血肿周围脑组织TLR4、MD2蛋白。结果:与正常组相比,脑出血组脑组织细胞结构异常,表现为水肿、坏死等,可见大量炎症细胞浸润,神经功能损伤评分、脑含水量、Iba-1+iNOS共阳性小胶质细胞数量、TNF-α、IL-1β水平、TLR4、MD2蛋白水平升高,Iba-1+CD206共阳性小胶质细胞数量、IL-10、Arg-1水平降低(P<0.05);与脑出血组相比,Gal-L组、Gal-M组、Gal-H组细胞水肿、坏死及炎症细胞浸润现象有所缓解,神经功能损伤评分、脑含水量、Iba-1+iNOS共阳性小胶质细胞数量、TNF-α、IL-1β水平、TLR4、MD2蛋白水平降低,Iba-1+CD206共阳性小胶质细胞数量、IL-10、Arg-1水平升高(P<0.05);与Gal-H组相比,Gal-H+RS09组细胞水肿、坏死及炎症细胞浸润现象严重,神经功能损伤评分、脑含水量、Iba-1+iNOS共阳性小胶质细胞数量、TNF-α、IL-1β水平、TLR4、MD2蛋白水平升高,Iba-1+CD206共阳性小胶质细胞数量、IL-10、Arg-1水平降低(P<0.05)。结论:Gal改善脑出血大鼠神经炎症的机制可能与抑制TLR4/MD2信号通路有关。 展开更多
关键词 高良姜素 Toll样受体4/髓样分化蛋白-2信号通路 脑出血 神经炎症 小胶质细胞
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