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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
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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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Oscillatory flow reactor facilitates fast photochemical Wolff rearrangement toward synthesis ofα-substituted amides in flow
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作者 Huashan Huang Jingze Chen +3 位作者 Luyun Zhang Hong Yan Siqi Li Fen-Er Chen 《Chinese Chemical Letters》 2025年第2期361-365,共5页
A visible light-promoted fast photochemical Wolff rearrangement was developed toward synthesis ofα-substituted amides in continuous flow with the use of a photochemical oscillatory flow reactor(POFR).The control expe... A visible light-promoted fast photochemical Wolff rearrangement was developed toward synthesis ofα-substituted amides in continuous flow with the use of a photochemical oscillatory flow reactor(POFR).The control experiment indicates that a fast process of the Wolff rearrangement(<40 s)is involved.Notably,this protocol does not require excess use of any reactants,and the resultingα-substituted amides could be isolated by recrystallization in good to excellent yields. 展开更多
关键词 Flow photochemistry Oscillatory flow reactor Wolff rearrangement KETENE α-substituted amides
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基于Nrf2/GPX4通路调控铁死亡探讨黄连解毒汤对动脉粥样硬化小鼠的影响 被引量:8
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作者 龚兆会 高黎 +6 位作者 翟惠奇 余锦紫 褚庆民 罗川晋 卿立金 吴伟 李荣 《中国实验方剂学杂志》 北大核心 2025年第3期22-28,共7页
目的:研究黄连解毒汤通过改善铁死亡治疗动脉粥样硬化(AS)小鼠的作用机制。方法:取SPF级C57BL/6J小鼠10只为正常组,另取载脂蛋白E敲除(ApoE^(-/-))小鼠50只随机分为5组,分别为模型组、黄连解毒汤低、中、高剂量组和阿托伐他汀组(ATV组)... 目的:研究黄连解毒汤通过改善铁死亡治疗动脉粥样硬化(AS)小鼠的作用机制。方法:取SPF级C57BL/6J小鼠10只为正常组,另取载脂蛋白E敲除(ApoE^(-/-))小鼠50只随机分为5组,分别为模型组、黄连解毒汤低、中、高剂量组和阿托伐他汀组(ATV组)。ApoE^(-/-)小鼠采用高脂饲料喂食8周构建AS模型,并在第9周开始分别予生理盐水,黄连解毒汤低、中、高剂量(3.9、7.8、15.6 g·kg^(-1)·d^(-1))和阿托伐他汀钙片(0.01 g·kg^(-1)·d^(-1))灌胃,共给药8周。采用大体油红O染色和马松(Masson)染色观察小鼠主动脉斑块的形成情况,自动生化分析仪测定血脂四项总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)水平,透射电镜观察主动脉线粒体结构,酶联免疫吸附测定法(ELISA)检测血清中超氧化物歧化酶(SOD)水平,微板法检测血清中还原型谷胱甘肽(GSH)含量,TBA法检测血清中丙二醛(MDA)含量,蛋白免疫印迹法检测小鼠主动脉核因子E_(2)相关因子2(Nrf2)/谷胱甘肽过氧化物酶4(GPX4)信号通路蛋白表达。结果:与正常组比较,模型组主动脉管腔斑块沉积,血清TC、LDL-C、TG、HDL-C、MDA含量显著升高(P<0.01),血清SOD、GSH和主动脉Nrf2、溶质载体家族7成员11(SLC7A11)、GPX4的表达水平均显著降低(P<0.01),主动脉线粒体碎裂、空泡化、体积萎缩,线粒体内嵴减少或者呈现松散、紊乱的形态。与模型组比较,黄连解毒汤低、中、高剂量组和ATV组主动脉管腔斑块沉积明显减少,小鼠血清TC、LDL-C、TG和MDA含量明显降低(P<0.05,P<0.01),血清SOD、GSH水平和主动脉Nrf2、SLC7A11、GPX4的表达水平升高(P<0.05,P<0.01),主动脉线粒体空泡化症状减轻,嵴数量增多且排序整齐。结论:黄连解毒汤能减轻AS小鼠主动脉管腔斑块沉积,降低血脂和MDA表达,升高SOD和GSH表达,改善铁死亡病理改变,其作用机制与Nrf2/GPX4信号通路有关。 展开更多
关键词 黄连解毒汤 动脉粥样硬化 铁死亡 核因子E_(2)相关因子2(Nrf2)/谷胱甘肽过氧化物酶4(GPX4)信号通路
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基于TLR4 NF-κB通路-神经相关因子探究依达拉奉对急性脑梗死患者炎症反应与神经损伤的保护机制 被引量:6
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作者 李莉 姜雪 +1 位作者 姜荣格 李恳 《中国实用神经疾病杂志》 2025年第1期47-52,共6页
目的基于Toll样受体4(TLR4)核因子-κB(NF-κB)通路-神经相关因子探究依达拉奉对急性脑梗死(ACI)患者炎症反应与神经损伤的保护机制。方法选取2020-07—2023-07保定市第一中心医院收治的110例ACI患者,以随机数字表法分为观察组、对照组,... 目的基于Toll样受体4(TLR4)核因子-κB(NF-κB)通路-神经相关因子探究依达拉奉对急性脑梗死(ACI)患者炎症反应与神经损伤的保护机制。方法选取2020-07—2023-07保定市第一中心医院收治的110例ACI患者,以随机数字表法分为观察组、对照组,各55例,对照组给予阿替普酶溶栓,观察组给予阿替普酶溶栓联合依达拉奉治疗。比较2组疗效、神经功能[美国国立卫生研究院卒中量表(NIHSS)评分、改良Rankin评分]、TLR4 NF-κB通路指标(TLR4、NF-κB)、神经损伤相关因子[神经元特异性烯醇化酶(NSE)、中枢神经特异性蛋白(S-100β)、脑源性神经营养因子(BDNF)]、TLR4 NF-κB通路相关炎症因子[白介素-1β(IL-1β)、超敏C反应蛋白(hs-CRP)、肿瘤坏死因子(TNF-α)、五聚素3(PTX3)、脂蛋白相关磷脂酶A2(Lp-PLA2)]。结果观察组总有效率96.36%,高于对照组的83.64%(P<0.05)。治疗1、2周观察组NIHSS评分、改良Rankin评分均低于对照组(P<0.05),观察组TLR4、NF-κB均低于对照组(P<0.05)。相较于治疗前,2组治疗1、2周后S-100β、NSE水平明显下降,BDNF水平明显升高,观察组S-100β、NSE水平均低于对照组,BDNF水平高于对照组(P<0.05)。相较于治疗前,2组治疗1、2周后IL-1β、hs-CRP、TNF-α、PTX3、Lp-PLA2水平均明显下降,观察组IL-1β、hs-CRP、TNF-α、PTX3、Lp-PLA2水平均低于对照组(P<0.05)。结论依达拉奉对ACI患者的疗效显著,有利于缓解炎症反应,改善神经损伤,其保护机制可能与TLR4 NF-κB通路调控神经损伤、炎症反应相关因子有关。 展开更多
关键词 急性脑梗死 TOLL样受体4 核因子-ΚB 依达拉奉 TLR4 NF-κB通路
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磁性纳米ZnFe_(2)O_(4)/Ag_(3)PO_(4)复合材料的合成及光催化降解性能 被引量:2
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作者 颜秀花 房娟 唐兰勤 《环境科学学报》 北大核心 2025年第1期135-142,共8页
磁性纳米复合材料作为一种具有回收再利用特性的新型催化剂,在环境科学领域受到了广泛的关注.本研究用水热法合成了磁性纳米ZnFe_(2)O_(4)/Ag_(3)PO_(4)复合材料.X射线衍射(XRD)、紫外-可见漫反射光谱(UV-vis DRS)和扫描电子显微镜(SEM... 磁性纳米复合材料作为一种具有回收再利用特性的新型催化剂,在环境科学领域受到了广泛的关注.本研究用水热法合成了磁性纳米ZnFe_(2)O_(4)/Ag_(3)PO_(4)复合材料.X射线衍射(XRD)、紫外-可见漫反射光谱(UV-vis DRS)和扫描电子显微镜(SEM)对合成的纳米复合材料进行了表征.同时,研究了ZnFe_(2)O_(4)/Ag_(3)PO_(4)复合材料在可见光下降解亚甲基蓝的催化性能.光催化降解结果表明,复合材料对亚甲基蓝的降解能力受ZnFe_(2)O_(4)与Ag_(3)PO_(4)的物质的量的比影响较大,当ZnFe_(2)O_(4)与Ag_(3)PO_(4)的物质的量的比为0.1∶1时,所得复合材料的光催化活性最高.与纯Ag_(3)PO_(4)相比,ZnFe_(2)O_(4)/Ag_(3)PO_(4)具有优异的结构稳定性和循环利用性能.循环4次后,ZnFe_(2)O_(4)/Ag_(3)PO_(4)的回收率为93.1%,光照60 min对亚甲基蓝的降解率为54.5%,回收率下降了5.1%,亚甲基蓝降解率下降了8.1%,而纯的Ag_(3)PO_(4)样品经过4次循环使用后,回收率下降了50.2%,亚甲基蓝的降解率下降了28.7%,说明ZnFe_(2)O_(4)的加入,提高了复合材料的稳定性和磁回收特性.自由基捕获实验表明空穴(h^(+))和超氧自由基(·O_(2)^(-))是亚甲基蓝降解反应中的主要活性物质. 展开更多
关键词 ZnFe_(2)O_(4)/Ag_(3)PO_(4)复合材料 光催化降解 稳定性 磁性
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莪术抗抑郁有效成分筛选及其调控Nrf2/GPX4/GSH通路的作用机制 被引量:2
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作者 宋永贵 段德林 +7 位作者 赖美茜子 刘亚丽 艾志福 朱根华 徐焕华 郑琴 杨明 苏丹 《中国实验方剂学杂志》 北大核心 2025年第6期211-221,共11页
目的:对莪术抗抑郁有效成分进行筛选、评价,并从抗氧化角度探索其调控核因子E2相关因子2(Nrf2)/谷胱甘肽(GSH)过氧化物酶4(GPX4)/GSH通路的作用机制。方法:采用1,1-二苯基-2-三硝基苯肼(DPPH)、2,2'-联氮-二(3-乙基-苯并噻唑-6-磺酸... 目的:对莪术抗抑郁有效成分进行筛选、评价,并从抗氧化角度探索其调控核因子E2相关因子2(Nrf2)/谷胱甘肽(GSH)过氧化物酶4(GPX4)/GSH通路的作用机制。方法:采用1,1-二苯基-2-三硝基苯肼(DPPH)、2,2'-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(ABTS)自由基清除实验检测包括莪术醇、莪术酮、莪术二酮、莪术烯、莪术烯醇、莪术双环烯酮、去氢莪术二酮、异莪术烯醇、莪术呋喃二烯酮、莪术呋喃二烯、蓬莪术环氧酮在内的莪术11种特征成分的体外抗氧化活性。通过慢性不可预知应激(CUMS)建立果蝇抑郁模型,将W1118野生型黑腹雄性果蝇随机分为空白组、模型组、莪术醇组、莪术酮组、莪术二酮组、莪术烯组、莪术烯醇组、莪术双环烯酮组、去氢莪术二酮组、异莪术烯醇组、莪术呋喃二烯酮组、莪术呋喃二烯组、蓬莪术环氧酮组和氟西汀组(10μmol·L^(-1)),其中,莪术11种特征成分给药组剂量均为0.1 g·L^(-1),空白组和模型组给予等体积的溶媒。采用糖水偏好实验、攀爬实验、强迫游泳实验,评价果蝇抑郁行为学指标,采用液相色谱-质谱法评价果蝇大脑中5-羟色胺(5-HT)和多巴胺(DA)的水平,并采用熵权法综合评价确定莪术抗抑郁有效成分。此外,将7周龄C57BL/6J小鼠随机分为空白组,模型组,莪术烯低、高剂量组(0.5、1 mg·kg^(-1))和氟西汀组(10 mg·kg^(-1)),采用CUMS建立抑郁小鼠模型,结合行为学确认最佳活性成分莪术烯的抗抑郁效果。流式细胞术检测小鼠海马中活性氧(ROS)的含量;酶联免疫吸附测定法(ELISA)检测三磷酸腺苷(ATP)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、GSH含量的影响;透射电镜观察莪术烯对海马组织线粒体超微结构的影响;蛋白免疫印迹法(Western blot)测定莪术烯对Nrf2蛋白水平的影响,并采用Nrf2抑制剂ML385验证其抗抑郁作用与调控Nrf2的关系;实时荧光定量聚合酶链式反应(Real-time PCR)检测莪术烯对GPX mRNA表达水平的影响。结果:体外抗氧化结果显示,具有六并五呋喃骨架的莪术烯和莪术酮清除自由基能力最为显著;熵权法综合评价结果显示,莪术烯是最具潜力的活性成分。与空白组比较,模型组小鼠糖水偏好系数和进入旷场中心次数显著下降(P<0.01),强迫游泳和悬尾实验的不动时间显著增加(P<0.01);海马组织中ROS含量显著升高(P<0.01),ATP含量显著下降(P<0.01);线粒体嵴紊乱,内膜空泡化,破坏严重;Nrf2蛋白表达水平明显下降(P<0.05),抗氧化酶SOD、CAT和GSH含量明显下降(P<0.05,P<0.01),GPX家族中GPX1、GPX4、GPX7基因表达水平显著下降(P<0.01)。与模型组比较,莪术烯高剂量组小鼠糖水偏好系数和进入旷场中心次数明显增加(P<0.05),游泳和悬尾不动时间明显减少(P<0.05,P<0.01);ROS含量显著下降(P<0.01),ATP含量明显增加(P<0.05);线粒体损伤减轻;Nrf2蛋白表达水平明显增加(P<0.05),Nrf2抑制剂ML385可逆转莪术烯对CUMS小鼠抑郁行为的改善作用;GSH含量显著增加(P<0.01),SOD和CAT含量无显著性差异;GPX4基因表达水平明显增加(P<0.05),而其他GPX家族基因差异均为统计学意义。结论:莪术烯为莪术中具有抗抑郁活性的最佳成分,其可能通过调控Nrf2,及其下游GPX4/GSH通路,而非CAT或SOD途径,改善线粒体功能障碍,发挥抗抑郁作用。 展开更多
关键词 莪术 抑郁症 药效评价 作用机制 氧化应激 核因子E2相关因子2(Nrf2)/谷胱甘肽过氧化物酶4(GPX4)/谷胱甘肽(GSH)通路
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ANGPTL4 TSP-1及CyPA与脑卒中后癫痫患者认知功能的关系 被引量:1
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作者 高灵利 方建 +2 位作者 李晓晖 李延红 耿智凡 《中国实用神经疾病杂志》 2025年第1期63-67,共5页
目的探讨血管生成素样蛋白4(ANGPTL4)、凝血酶敏感蛋白-1(TSP-1)、亲环素A(CyPA与脑卒中后癫痫患者认知功能的关系。方法选取2021-01—2022-12河南大学第一附属医院神经内科收治的100例脑卒中后癫痫病例进行观察,按简易精神状态量表(MM... 目的探讨血管生成素样蛋白4(ANGPTL4)、凝血酶敏感蛋白-1(TSP-1)、亲环素A(CyPA与脑卒中后癫痫患者认知功能的关系。方法选取2021-01—2022-12河南大学第一附属医院神经内科收治的100例脑卒中后癫痫病例进行观察,按简易精神状态量表(MMSE)划分认知障碍标准将患者分为认知障碍组(50例)和认知正常组(50例),应用酶联免疫吸附试验(ELISA)检测2组患者的血清ANGPTL4、TSP-1、CyPA水平,MMSE量表测评2组患者的认知功能。结果与认知正常组比较,认知障碍组患者MMSE评分降低,ANGPTL4、TSP-1、CyPA水平升高(P<0.05);与轻度认知障碍患者比较,中度认知障碍患者血清ANGPTL4、TSP-1、CyPA水平升高(P<0.05);与中度认知障碍患者比较,重度认知障碍患者血清ANGPTL4、TSP-1、CyPA水平升高(P<0.05)。在脑卒中后癫痫患者中,血清ANGPTL4、TSP-1、Cy PA与MMSE评分各维度均呈负相关(P<0.05)。结论脑卒中后癫痫会降低MMSE评分,提高患者血清ANGPTL4、TSP-1、CyPA水平。ANGPTL4、TSP-1、CyPA水平越高,患者认知功能障碍越严重。 展开更多
关键词 脑卒中后癫痫 血管生成素样蛋白4 凝血酶敏感蛋白-1 亲环素A 认知功能
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亚麻新品种龙油麻4号的选育及栽培技术 被引量:3
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作者 宋喜霞 吴广文 +7 位作者 康庆华 袁红梅 姜卫东 姚丹丹 姚玉波 唐立郦 刘丹丹 杨洌 《中国麻业科学》 2025年第1期14-17,共4页
龙油麻4号是黑龙江省农业科学院经济作物研究所2009年以内亚6号为母本,陇亚8号为父本组配杂交09065,通过系统选择培育出的丰产性好、含油率高、抗旱性强的亚麻新品种。于2023年2月通过农业农村部非主要农作物品种登记,适宜在我国黑龙江... 龙油麻4号是黑龙江省农业科学院经济作物研究所2009年以内亚6号为母本,陇亚8号为父本组配杂交09065,通过系统选择培育出的丰产性好、含油率高、抗旱性强的亚麻新品种。于2023年2月通过农业农村部非主要农作物品种登记,适宜在我国黑龙江省亚麻主产区种植。文章主要介绍了龙油麻4号的选育过程、特征特性、产量情况及栽培技术要点,旨在为该品种的大面积推广提供技术支持和帮助。 展开更多
关键词 亚麻 新品种 龙油麻4 选育 栽培技术
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独活寄生汤对老年膝骨关节炎血清TLR4/NF-κB信号通路的影响 被引量:5
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作者 薛英 田永祥 +1 位作者 刘峰瑞 郝耀 《中华中医药学刊》 北大核心 2025年第4期201-205,共5页
目的观察独活寄生汤用于老年膝骨关节炎疗效及其对Toll样受体4(TLR4)/核转录因子κB(NF-κB)信号通路的影响。方法将118例老年膝骨关节炎患者按照随机数字表法分为观察组和对照组,各59例。对照组患者给予盐酸氨基葡萄糖片治疗,观察组在... 目的观察独活寄生汤用于老年膝骨关节炎疗效及其对Toll样受体4(TLR4)/核转录因子κB(NF-κB)信号通路的影响。方法将118例老年膝骨关节炎患者按照随机数字表法分为观察组和对照组,各59例。对照组患者给予盐酸氨基葡萄糖片治疗,观察组在对照组基础上联合独活寄生汤治疗,4周为1个疗程,共治疗2个疗程。比较两组临床疗效,比较两组治疗前后中医证候积分、西安大略和麦克马斯特大学骨关节炎指数(WOMAC)量表评分及视觉模拟量表(VAS)评分,观察两组治疗前后血清白细胞介素-6(IL-6)、基质金属蛋白酶-1(MMP-1)、骨钙素(BGP)、I型前胶原羧基末端肽β降解产物(β-CTX)、I型前胶原羧基末端肽(PICP)水平及TLR4、NF-κB蛋白表达。结果治疗后观察组总有效率96.61%(57/59)高于对照组的83.05%(49/59),差异有统计学意义(P<0.05);治疗后两组各项中医证候积分较治疗前降低,并且观察组均低于对照组(P<0.05);治疗后,两组WOMAC评分及VAS评分较治疗前降低,并且观察组低于对照组(P<0.05);治疗后两组IL-6、MMP-1及TLR4、NF-κB蛋白水平较治疗前降低,并且观察组均低于对照组(P<0.05);治疗后,两组血清BGP、PICP水平较治疗前升高,并且观察组高于对照组,两组血清β-CTX水平较治疗前降低,并且观察组低于对照组(P<0.05)。结论独活寄生汤用于老年膝骨关节炎患者有利于提高临床疗效,减轻疼痛、乏力等症状,并改善关节功能,其作用机制可能与改善骨代谢指标、通过TLR4/NF-κB信号通路抑制炎症因子水平、减轻软骨损伤等因素有关。 展开更多
关键词 膝骨关节炎 独活寄生汤 TOLL样受体4 核转录因子ΚB 炎症因子
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栀子苷调节TLR4/MyD88/NF-κB信号通路缓解膝骨关节炎大鼠的炎症反应 被引量:3
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作者 张健 颜运涛 +4 位作者 王响 焦永伟 李锡 杨琦 任伟亮 《中药药理与临床》 北大核心 2025年第5期22-27,共6页
目的:探究栀子苷对大鼠膝骨关节炎(knee osteoarthritis, KOA)的影响及其潜在机制。方法:建立碘乙酸钠诱导的大鼠KOA模型,并随机分为:正常对照组、模型对照组、栀子苷30、60、120 mg/kg组和阳性对照双氯芬酸6 mg/kg组。采用苏木精-伊红(... 目的:探究栀子苷对大鼠膝骨关节炎(knee osteoarthritis, KOA)的影响及其潜在机制。方法:建立碘乙酸钠诱导的大鼠KOA模型,并随机分为:正常对照组、模型对照组、栀子苷30、60、120 mg/kg组和阳性对照双氯芬酸6 mg/kg组。采用苏木精-伊红(HE)和番红O-固绿(SO/FG)染色观察软骨组织病理变化,并使用Mankin评分原则进行定量评分;应用透射电镜术(TEM)观察软骨组织的超微结构;使用ELISA试剂盒检测血清中基质金属蛋白酶-13(MMP-13)、白细胞介素-1β(IL-1β)、IL-6、肿瘤坏死因子-α(TNF-α)、丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GPx)和过氧化氢酶(CAT)的含量或活力;采用定量逆转录PCR(RT-qPCR)检测软骨组织Toll样受体4(Tlr4)、髓样分化因子88(Myd88)和核转录因子κB(Nfκb)mRNA表达;以Western blot检测TLR4/MyD88/NFκB通路相关蛋白表达。结果:与正常对照组比较,模型对照组出现明显的软骨组织破坏、关节炎症和氧化应激反应血清中炎症因子含量升高,软骨组织Tlr4、Myd88、Nfkb的mRNA和蛋白表达显著上调(P<0.01);与模型对照组相比,栀子苷60、120 mg/kg组软骨破坏和其他病变显著改善,血清中MMP13、IL-1β、TNF-α和IL-6的含量明显降低,氧化应激反应被明显抑制,软骨组织Tlr4、Myd88、Nfkb的mRNA和蛋白表达明显下调(P<0.05或P<0.01)。结论:栀子苷通过调节TLR4/MyD88/NFκB信号通路降低炎症细胞因子释放和氧化应激水平,保护KOA大鼠的关节软骨免受损伤。 展开更多
关键词 栀子苷 膝骨关节炎 软骨损伤 氧化应激 炎症反应 Toll样受体4 髓样分化因子88 核转录因子ΚB
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