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具有三活性物种的离子型活性聚合反应的动力学模型
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作者 颜德岳 叶鹏 《中国科学(B辑)》 CSCD 北大核心 1998年第5期415-420,共6页
离子型活性聚合反应体系一般具有 3种活性物种 ,即结合紧密的离子对 ,被溶剂化的疏松离子对及自由离子 .所有这些物种都能进行链增长反应 ,并且松离子对同时与紧离子对和自由离子处于热力学平衡状态 .以具有三活性物种的阴离子型聚合反... 离子型活性聚合反应体系一般具有 3种活性物种 ,即结合紧密的离子对 ,被溶剂化的疏松离子对及自由离子 .所有这些物种都能进行链增长反应 ,并且松离子对同时与紧离子对和自由离子处于热力学平衡状态 .以具有三活性物种的阴离子型聚合反应体系为例 ,对聚合产物的各种分子参数 ,例如数均与重均聚合度及多分散指数进行了理论推导 .数值计算结果表明 ,虽然 3种共存物种的反应活性很不相同 。 展开更多
关键词 活性聚合反应 动力学 三态机理 物种 离子型
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活性自由基聚合反应与多种结构聚合物的制备
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作者 姚宁 《河北化工》 2001年第4期9-11,共3页
介绍了原子转移自由基聚合反应这一新型的活性自由基聚合方式 ,并综述了利用这种聚合方法制备的多种结构的聚合物 ,包括嵌段共聚物、交替共聚物、接枝共聚物、星形聚合物、超支化聚合物。
关键词 活性自由基聚合反应 原子转移自由基聚合反应 嵌段共聚物 制备
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原子转移自由基聚合反应制备多种结构的聚合物 被引量:1
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作者 袁金磊 姚宁 《河北师范大学学报(自然科学版)》 CAS 2001年第4期496-500,共5页
介绍了原子转移自由基聚合反应这一新型的活性自由基聚合方式 ;综述了利用这种聚合方法制备的多种结构的聚合物 ,包括嵌段共聚物、交替共聚物、接枝共聚物、星形聚合物、超支化聚合物。
关键词 活性自由基聚合反应 原子转移自由基聚合反应 嵌段共聚物 交替共聚物 接枝共聚物
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活性自由基聚合的新进展——原子转移自由基聚合 被引量:1
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作者 谭英杰 梁玉蓉 《山西化工》 2004年第1期11-15,共5页
活性自由基聚合是目前高分子科学中最为活跃的研究领域之一 ,原子转移自由基聚合 (ATRP)反应是实现活性聚合的一种颇为有效的途径 ,也是高分子化学领域的最新研究进展之一。 ATRP的独特之处在于使用了卤代烷作引发剂 ,并用过渡金属催化... 活性自由基聚合是目前高分子科学中最为活跃的研究领域之一 ,原子转移自由基聚合 (ATRP)反应是实现活性聚合的一种颇为有效的途径 ,也是高分子化学领域的最新研究进展之一。 ATRP的独特之处在于使用了卤代烷作引发剂 ,并用过渡金属催化剂或退化转移的方式 ,有效地抑制了自由基双基终止的反应。 ATRP可以同时适用于非极性和极性单体 ,可以制备多种结构形式的、结构清晰的高分子化合物。可实现众多单体的活性 /可控自由基聚合。介绍了 ATRP的研究进展 ,包括 ATRP反应的特点、聚合反应机理、应用、研究现状及前景展望。 展开更多
关键词 活性聚合反应 原子转移聚合反应 自由基双基终止 进展 特点 机理 应用 前景
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以NaNO_2/FeSO_4·7H_2O控制苯乙烯活性自由基聚合的研究
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作者 许淼清 颜明发 +4 位作者 黄剑莹 林强 林明华 陈一虹 邹友思 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第2期242-245,共4页
研究了NaNO2/FeSO4·7H2O存在下苯乙烯的活性自由基聚合.发现亚硝酸钠与硫酸亚铁反应生成的 NO能够与AIBN裂解的自由基,生成氧氮自由基,且能控制苯乙烯的自由基聚合.当 AIBN/NaNO2/FeSO4 ·7H2O的摩尔比为1/2.5/2.5时,得到分子... 研究了NaNO2/FeSO4·7H2O存在下苯乙烯的活性自由基聚合.发现亚硝酸钠与硫酸亚铁反应生成的 NO能够与AIBN裂解的自由基,生成氧氮自由基,且能控制苯乙烯的自由基聚合.当 AIBN/NaNO2/FeSO4 ·7H2O的摩尔比为1/2.5/2.5时,得到分子量分布较窄,分子量在5万以下可控的聚合物,实测分子量与理论分子量相近.聚合过程中转化率随反应时间增长而增高,分子量随转化率增高而增大,具有典型活性自由基聚合的特征.经纯化后的聚苯乙烯可作为大分子引发剂,引发新加入单体的聚合,证明是活的高分子. 展开更多
关键词 活性自由基聚合反应 亚硝酸钠 硫酸亚铁 稳定自由基 添加剂 聚合方法
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原子转移自由基聚合的研究进展 被引量:4
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作者 夏攀登 耿兵 +3 位作者 路翠苹 徐安厚 初善壮 张书香 《河南化工》 CAS 2005年第4期5-8,共4页
概述了原子转移自由基聚合(ATRP)反应的机理、引发剂的组成、催化体系、适用单体、聚合温度、反应介质的近期研究进展;介绍了ATRP作为一种新材料合成技术的产业化前景及其存在的问题。
关键词 活性自由基聚合反应(CRP) 原子转移自由基聚合(ATRP) 分子设计 产业化
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原子转移自由基聚合反应及其进展 被引量:12
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作者 袁金颖 楼旭东 潘才元 《化学通报》 CAS CSCD 北大核心 2000年第3期10-16,共7页
活性自由基聚合是目前高分子科学中最为活跃的研究领域之一,原子转移自由基聚合反应是实现活性聚合的一种颇为有效的途径,可实现众多单体的活性可控自由基聚合。此文综述有关原子转移自由基聚合反应及其最新进展。
关键词 活性聚合反应 原子转移 自由基聚合反应
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离子液体在高分子合成中的应用 被引量:2
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作者 周艳青 伍家卫 +2 位作者 唐蓉萍 陈淑芬 索陇宁 《化工技术与开发》 CAS 2014年第5期29-30,共2页
离子液体是一类新型的"软"功能材料或介质,具有优良的可设计性。它作为一种绿色溶剂,具有很多独特的物理化学性能。本文介绍了离子液体在自由基聚合反应、活性聚合反应、电化学聚合等高分子合成反应方面的应用。
关键词 离子液体 高分子合成 自由基聚合反应 活性聚合反应 电化学聚合
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新型环状聚(ε-己内酯-co-γ-三乙基硅氧基-ε-己内酯)的合成
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作者 刘超 杨长臻 +4 位作者 李微雪 张勇林 姚军善 雷良才 李海英 《应用化学》 CAS CSCD 北大核心 2014年第10期1135-1142,共8页
设计合成了具有精确分子结构的聚合物对深入了解其结构与性能之间的关系起着至关重要的作用。研究了一种合成带有三乙基硅氧侧基的环状无规共聚酯的新方法。功能性单体γ-三乙基硅氧基-ε-己内酯(γ-Et3SiOεCL)和ε-己内酯(ε-CL)在环... 设计合成了具有精确分子结构的聚合物对深入了解其结构与性能之间的关系起着至关重要的作用。研究了一种合成带有三乙基硅氧侧基的环状无规共聚酯的新方法。功能性单体γ-三乙基硅氧基-ε-己内酯(γ-Et3SiOεCL)和ε-己内酯(ε-CL)在环状引发剂2,2-二丁基-2-锡-1,3-二氧环庚烷(DSDOP)的作用下,进行活性开环聚合反应以制备活性环状无规共聚酯(LCP(εCLcoγEt3SiOεCL))前体,当单体完全转化后,以该活性环状前体作为大分子引发剂,引发反应性单体α-(1-丙烯酰氧乙基)-ε-己内酯(αAEεCL)进行嵌段聚合反应,合成了在活性中心附近带有不饱和双键的功能性环状嵌段共聚酯,即活性环状聚(ε-己内酯-co-γ-三乙基硅氧基-ε-己内酯)-b-(α-(1-丙烯酰氧乙基)-ε-己内酯)。最后该活性环状嵌段共聚酯在紫外光照射下,反应性单体结构单元中的双键发生分子内交联反应,从而制得稳定的不含有机锡的新型环状无规共聚酯cP(εCLcoγEt3SiOεCL)(Mn,NMR=28500)。采用SEC、1H NMR以及DSC等技术手段对聚合物的结构和性能进行表征。该方法的突出特点是能够高效地合成带有功能性侧基的高相对分子质量的环状无规共聚酯。 展开更多
关键词 活性开环聚合反应 环状无规共聚酯 环状聚(γ-三乙基硅氧基-ε-己内酯) 分子内交联反应 环状聚ε-己内酯
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聚甲基丙基二烯丙基氯化铵的合成及表征 被引量:2
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作者 张秀娟 贾旭 +1 位作者 张跃军 陶贤平 《精细化工》 EI CAS CSCD 北大核心 2019年第3期429-436,共8页
以甲基丙基二烯丙基氯化铵(MPDAAC)为单体、2,2'-偶氮二异丁基脒二盐酸盐(V50)为引发剂,通过水溶液聚合法制备了聚甲基丙基二烯丙基氯化铵(PMPDAAC)。在单因素实验基础上,以产物特征黏度值为考察指标,采用响应分析法中的Box-Behnke... 以甲基丙基二烯丙基氯化铵(MPDAAC)为单体、2,2'-偶氮二异丁基脒二盐酸盐(V50)为引发剂,通过水溶液聚合法制备了聚甲基丙基二烯丙基氯化铵(PMPDAAC)。在单因素实验基础上,以产物特征黏度值为考察指标,采用响应分析法中的Box-Behnken模型对PMPDAAC的制备工艺进行了优化。得到最优条件为:三步升温温度分别为56.1、61.2、80.2℃,w(MPDAAC)=71.03%、w(V50)=2.50%和w(Na4EDTA)=0.0074%。得到PMPDAAC的特征黏度值平均为1.17 dL/g,单体转化率为92.05%。采用FTIR、NMR和GPC-MALLS对其产物进行了结构表征及相对分子量测定,测得Mw最高为2.658×10~5,多分散指数d(M_w/M_n)=1.358。研究表明,取代基丙基引入所带来的空间位阻和可能的溶剂效应是影响二烯丙基季铵盐聚合反应活性的主要因素。 展开更多
关键词 甲基丙基二烯丙基氯化铵 均聚反应 工艺优化 响应曲面 特征黏度 聚合反应活性 表面活性
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(-)-Epigallocatechin-3-gallate inhibits VEGF expression induced by IL-6 via Stat3 in gastric cancer 被引量:21
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作者 Bao-He Zhu Hua-Yun Chen +5 位作者 Wen-Hua Zhan Cheng-You Wang Shi-Rong Cai Zhao Wang Chang-Hua Zhang Yu-Long He 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第18期2315-2325,共11页
AIM: To demonstrate that (-)-Epigallocatechin-3-gallate (EGCG) inhibits vascular endothelial growth factor (VEGF) expression and angiogenesis induced by interleukin-6 (IL-6) via suppressing signal transducer and activ... AIM: To demonstrate that (-)-Epigallocatechin-3-gallate (EGCG) inhibits vascular endothelial growth factor (VEGF) expression and angiogenesis induced by interleukin-6 (IL-6) via suppressing signal transducer and activator of transcription 3 (Stat3) activity in gastric cancer. METHODS: Human gastric cancer (AGS) cells were treated with IL-6 (50 ng/mL) and EGCG at different concentrations. VEGF, total Stat3 and activated Stat3 protein levels in the cell lyses were examined by Western blotting, VEGF protein level in the conditionedmedium was measured by enzyme-linked immunosorbent assay, and the level of VEGF mRNA was evaluated by reverse transcription polymerase chain reaction (RTPCR). Stat3 nuclear translocation was determined by Western blotting with nuclear extract, and Stat3-DNA binding activity was examined with Chromatin immunoprecipitation (ChIP) assay. IL-6 induced endothelial cell proliferation was measured with 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazoliumbromide assay, in vitro angiogenesis was determined with endothelial cell tube formation assay in Matrigel, and IL-6-induced angiogenesis in vitro was measured with Matrigel plug assay. RESULTS: There was a basal expression and secretion of VEGF in AGS cells. After stimulation with IL-6, VEGF expression was apparently up-regulated and a 2.4-fold increase was observed. VEGF secretion in the conditioned medium was also increased by 2.8 folds. When treated with EGCG, VEGF expression and secretion were dose-dependently decreased. IL-6 also increased VEGF mRNA expression by 3.1 folds. EGCG treatment suppressed VEGF mRNA expression in a dose-dependent manner. EGCG dose-dependently inhibited Stat3 activation induced by IL-6, but did not change the total Stat3 expression. When treated with EGCG or AG490, VEGF expressions were reduced to the level or an even lower level in the tumor cells not stimulated with IL-6. However, PD98059 and LY294002 did not change VEGF expression induced by IL-6. EGCG inhibited Stat3 nucleus translocation, and Stat3-DNA binding activity was also markedly decreased by EGCG. Furthermore, EGCG inhibited IL-6 induced vascular endothelial cell proliferation and tube formation in vitro and angiogenesis in vitro . CONCLUSION: EGCG inhibits IL-6-induced VEGF expression and angiogenesis via suppressing Stat3 activity in gastric cancer, which has provided a novel mechanistic insight into the anti-angiogenic activity of EGCG. 展开更多
关键词 Epigallocatechin-3-gallate Vascular endothelial growth factor Signal transducer and activator of transcription 3 ANGIOGENESIS Gastric cancer
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Monte Carlo Simulation of Propylene Polymerization (Ⅰ) Effects of Impurity on Propylene Polymerization 被引量:8
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作者 罗正鸿 曹志凯 苏耀堂 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第2期194-199,共6页
A comprehensive mechanism for propylene polymerization was proposed by considering the effects of main impurities in the material on propylene polymerization. According to the proposed mechanism, Monte Carlo simulatio... A comprehensive mechanism for propylene polymerization was proposed by considering the effects of main impurities in the material on propylene polymerization. According to the proposed mechanism, Monte Carlo simulation was employed to investigate the polymerization kinetics in order to determine the effects of the main impurities on the polymerization. Significant influences of the main impurities on the rate, number-average degree and controlling capability of hydrogen of the polymerization were analyzed. 展开更多
关键词 Monte Carlo simulation active impurity propylene polymerization kinetics
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Effects of octreotide on glucose transporter type 2expression in obese rat small intestine 被引量:4
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作者 Na Wei Rui Liu +4 位作者 Yan Ou Xian Li Ou Qiang Wei Guo Cheng-Wei Tang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第39期4434-4439,共6页
AIM: TO investigate the effects of the somatostatin analogue, octreotide, on maltose and sucrase activities and expression of glucose transporter type 2 (GLUT2) in obese rat intestinal mucosa. METHODS: We divided ... AIM: TO investigate the effects of the somatostatin analogue, octreotide, on maltose and sucrase activities and expression of glucose transporter type 2 (GLUT2) in obese rat intestinal mucosa. METHODS: We divided 49 Sprague-Dawley rats into a group of 31 high fat diet-induced obese rats and a group of 18 normal controls. The obese rats were separated into an octreotide treated group 9f 16 rats and an obese group of 15. The intervention (:jroup was injected with octreotide at 40 ±g/kg body weight every 12 h for 8 d. Rat body weight was measured weekly to calculate Lee's index. After euthanization, maltase and sucrase activities in the small intestine were measured by activity assays, and the fasting plasma glucose level was measured. The expression of GLUT2 in small intestinal mucosa was analyzed by immunohistochemistry, reverse transcriptase polymerase chain reaction and Western blotting assays. RESULTS: Body weight, Lee's index, fasting plasma glucose level, maltase activity in small intestinal mucosa, mucosa and apical GLUT2, GLUT2 mRNA and protein expression levels were all significantly higher in the obese group than in the normal control group (605.61 ± 141.00 vs 378.54 ±111.75, 337.61 ± 10.82 vs 318.73 ± 20.10, 8.60± 1.38 vs 7.33 ± 0.70, 156.01 ± 58.81 vs 50.43 ± 30.49, 390 744.2± 62 469.21 vs 170 546.50 ± 50 646.14, 26 740.18 ±3809.60 vs 354.98± 57.19, 0.26± 0.11 vs 0.07± 0.02, and 2.08 ± 0.59 vs 1.27 ± 0.38, respectively, all P 〈 0.01). Sucrase activity did not differ between the two groups. Octreotide intervention significantly decreased the body weight and fasting plasma glucose level of obese rats (508.27 ± 94.39 vs 605.61 ± 141.00, 7.58 ± 1.51 vs 8.60±1.38, respectively, all P 〈 0.05). The intestinal mucosa and apical GLUT2, expression of GLUT2 mRNA and protein were also significantly lower in the octreotide intervention group than in the obese group (269 975.2 ± 53 730.94 vs 390 744.2 ± 62 469.21, 3758.06 ± 364.51 vs 26 740.18 ± 3809.60, 0.08 ± 0.02 vs 0.26 ±0.11, and 1.31 ± 0.27 vs 2.08 ±0.59, respectively, all P 〈 0.01). CONCLUSION: High fat dietinduced obesity is associated with elevated intestinal maltase activity, GLUT2 expression, and permanent apical GLUT2 in the small intestinal mucosa of rats. Octreotide can inhibit these effects. 展开更多
关键词 Glucose transporter type 2 High fat diet MALTASE OBESITY OCTREOTIDE RAT Small intestinal absorption
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由高效双键易位闭环反应合成环状聚ε-己内酯 被引量:3
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作者 陈磊燕 徐博林 +1 位作者 李蒙 李海英 《高分子学报》 SCIE CAS CSCD 北大核心 2012年第7期743-748,共6页
研究了合成环状大分子的一种新方法,即借助活性开环聚合反应和高效双键易位闭环反应(RCMR)合成环状聚ε-己内酯.首先,ε-己内酯在环状引发剂2,2-二丁基-2-锡-1,3-二氧环庚烷(DSDOP)的作用下,进行活性开环聚合反应,获得双羟基封端的聚ε... 研究了合成环状大分子的一种新方法,即借助活性开环聚合反应和高效双键易位闭环反应(RCMR)合成环状聚ε-己内酯.首先,ε-己内酯在环状引发剂2,2-二丁基-2-锡-1,3-二氧环庚烷(DSDOP)的作用下,进行活性开环聚合反应,获得双羟基封端的聚ε-己内酯(PCLOH);然后,在对甲苯磺酸、1,3-二环己基碳二亚胺(DCC)和4-二甲氨基吡啶(DMAP)的作用下,将PCLOH与3-丁烯酸反应转化为双烯丙基封端的聚ε-己内酯(allylPCL);在Grubbs催化剂(Cl2(Cy3)2Ru CHPh)的作用下,将allylPCL经RCMR环化成环状聚ε-己内酯,并采用SEC,NMR,TGA以及DSC等技术对聚合物的结构和热力学性能进行了表征,SEC和黏度表征结果显示环状聚ε-己内酯具有较小的动态力学体积,TGA和DSC表征结果显示环状聚ε-己内酯的热分解温度较其线型前体高13℃,环化的结果使其熔点和结晶度下降.结果表明allylPCL在较稀(2.5×10-5mol/L)体系中,借助Grubbs催化剂进行的RCMR分子内环化反应效率高,环化产物无需进一步分离提纯. 展开更多
关键词 环状聚ε-己内酯 活性开环聚合反应 双键易位闭环反应
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新型功能性环状聚(ε-己内酯-co-α-氯代-ε-己内酯)的合成 被引量:1
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作者 高超 刘超 +3 位作者 姚军善 张勇林 雷良才 李海英 《高分子学报》 SCIE CAS CSCD 北大核心 2013年第11期1459-1466,共8页
借助活性开环聚合反应和紫外光辐照下的分子内交联反应合成新型功能性环状聚(ε-己内酯-co-α-氯代-ε-己内酯)(cP(εCLcoαClεCL)).首先,利用Baeyer-Villiger氧化法将α-氯代环己酮在间氯过氧苯甲酸(mCPBA)的作用下制得功能性单体α-... 借助活性开环聚合反应和紫外光辐照下的分子内交联反应合成新型功能性环状聚(ε-己内酯-co-α-氯代-ε-己内酯)(cP(εCLcoαClεCL)).首先,利用Baeyer-Villiger氧化法将α-氯代环己酮在间氯过氧苯甲酸(mCPBA)的作用下制得功能性单体α-氯代-ε-己内酯(αClεCL).然后,功能性单体αClεCL和ε-己内酯(εCL)在环状引发剂2,2-二丁基-2-锡-1,3-二氧环庚烷(DSDOP)的作用下,进行活性开环聚合反应获得活性环状无规共聚酯(LCP(εCLcoαClεCL))前体,该前体的分子量可以通过改变单体与引发剂的摩尔配比来控制.当单体完全转化后,该活性环状前体再引发反应性单体α-(1-丙烯酰氧乙基)-ε-己内酯(αAEεCL)进行嵌段聚合反应,合成了在活性中心附近带有不饱和双键的功能性环状共聚酯,即活性环状聚(ε-己内酯-co-α-氯代-ε-己内酯)-b-(α-(1-丙烯酰氧乙基)-ε-己内酯).最后该活性环状共聚酯在紫外光辐照下,反应性单体单元中的双键发生分子内交联反应,制得稳定的不含有机锡的新型功能性环状无规共聚酯cP-(εCLcoαClεCL)(M n,NMR=32400).采用SEC,NMR以及DSC等技术对聚合物的结构和性能进行表征,SEC和黏度表征结果显示新型功能性cP(εCLcoαClεCL)与分子量相同的线型共聚酯相比具有较小的动态力学体积,DSC表征结果显示共聚酯环化的结果使其熔点和结晶度下降.该方法的突出特点是能够高效地合成具有高分子量的环状聚合物. 展开更多
关键词 活性开环聚合反应 功能性环状无规共聚酯 环状聚(ε-己内酯-co-α-氯代-ε-己内酯) 分子内交联反应
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Effect of berberine on activity and mRNA expression of N-acetyl transferase in human lung cancer cell line A549 被引量:6
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作者 Shengyan Xi Kunhan Chuang +3 位作者 Kwangming Fang Yimin Lee Jinggung Chung Yaochen Chuang 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2014年第3期302-308,共7页
OBJECTIVE: To study the effects of berberine on ac- tivity and mRNA expression of N-acetyltransferase in human lung cancer cell line A549. METHODS: N-acetyltransferase antibodies wereprepared. The human lung cancer ... OBJECTIVE: To study the effects of berberine on ac- tivity and mRNA expression of N-acetyltransferase in human lung cancer cell line A549. METHODS: N-acetyltransferase antibodies wereprepared. The human lung cancer A549 cells were cultivated randomly in the wells of culture plate, and divided into the control group, and berberine 0.0008, 0.008, 0.08, 0.8 and 1.6 mM treatment groups, with 3 wells for each group. 24 h later, A549 cells in each group were collected respectively, the content of N-acetyltransferase was detected by Flow cytometry, and the mRNA expression of N-acetyltransferase was observed by reverse tran- scription polymerase chain reaction. RESULTS The N-acetyltransferase content in hu- man lung cancer A549 cells decreased with the in- creasing of berberine concentration, significantly lower than that in the control group (P〈O.05 or P〈 0.001); and the mRNA expression of N-acetyltrans- ferase also decreased with the increasing of berber- ine concentration, significantly lower in Huanglian- su treatment groups (P〈0.O01). CONCLUSION: Berberine can inhibit the activity of N-acetyltransferase in human lung cancer cell line A549, and shows negative correlations of dose and time in a certain extent. The inhibited gene expres- sion of N-acetyltransferase in human lung cancer A549 cell may probably represent one of the mech- anisms for its antineoplastic effect. 展开更多
关键词 BERBERINE ACETYLTRANSFERASES Cell line tumor NEOPLASMS
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Synthesis and photoactivity of pH-responsive amphiphilic block polymer photosensitizer bonded zinc phthalocyanine 被引量:1
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作者 Lü WangYang SUN ChunMei +4 位作者 LU Qin LI Nan WU DeZhou YAO YuYuan CHEN WenXing 《Science China Chemistry》 SCIE EI CAS 2012年第6期1108-1114,共7页
A zinc tetraaminophthalocyanine derivative, zinc tetra(methacryloyl moiety)aminophthalocyanine (MeZnAPc) (with a double bond) was synthesized by the reaction between zinc tetraaminophthalocyanine (ZnTAPc) and methacry... A zinc tetraaminophthalocyanine derivative, zinc tetra(methacryloyl moiety)aminophthalocyanine (MeZnAPc) (with a double bond) was synthesized by the reaction between zinc tetraaminophthalocyanine (ZnTAPc) and methacryloyl chloride. Atom transfer radical polymerization (ATRP) was employed as the polymerization technique to obtain a novel pH-responsive poly- meric photosensitizer (PEGIlo-b-P(DPA,rco-MeZnAPcm)) by copolymerizing of methoxypolyethylene glycols (MPEG) (as reducing agent), 2-(isopropylamino)ethyl methacrylate (DPA) and MeZnAPc. This photosensitizer was characterized by UV-vis spectroscopy, FTIR, ~H NMR, etc. The results indicated that the photosensitizer presented the well pH-responsive be- havior around the pH range 6.0-6.5 and the high photoactivity to 1,3-diphenylisobenzofuran (DPBF). The result of photoca- talysis oxidation of L-tryptophan (L-Try) suggested that zinc phthalocyanine could present high photoactivity due to its disper- sivity at pH 5.5 without formation of micelles, and its photoactivity decreased dramatically at pH 7.4 due to wrapping ZnTAPc into the micelles. Therefore, the novel pH-responsive polymeric photosensitizer has better application prospects in the field of photodynamic therapy. 展开更多
关键词 atom transfer radical polymerization PH-SENSITIVE zinc phthalocyanine polymer photosensitizer PHOTOACTIVITY
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Pingwei capsules improve gastrointestinal motility in rats with functional dyspepsia 被引量:3
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作者 Liang Qiankun Mao Lanfang +6 位作者 Du Xiaojuan Li Yunxia Yan Yuan Liang Jingjing Liu Junhong Wang Longde Li Hongfang 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2018年第1期43-53,共11页
OBJECTIVE: To investigate the mechanism of Ping-wei capsules(PWC) in improving gastrointestinal m otility in rats with functional dyspepsia(FD).METHODS: We established an FD model by stimu-lating semi-starvation rats ... OBJECTIVE: To investigate the mechanism of Ping-wei capsules(PWC) in improving gastrointestinal m otility in rats with functional dyspepsia(FD).METHODS: We established an FD model by stimu-lating semi-starvation rats via tail damping, provo-cation, and forced exercise fatigue. The FD model group was further divided into five groups accord-ing to the treatment received: normal saline, dom-peridone, low-dose PWC, mid-dose PWC, or highdose PWC. The effect of PWC on FD was evaluated by measuring gastrointestinal motility. Changes in leptin and cholecystokinin(CCK) were detected through enzyme-linked immunosorbent assay, re-verse transcription-polymerase chain reaction, and immunohistochemistry.RESULTS: PWC significantly increased gastrointesti-nal m otility in FD rats. Furthermore, PWC signifi-cantly increased CCK m RNA and protein concentra-tions in the duodenum and antrum, decreased leptin protein concentrations in the duodenum, an-trum, and hypothalamus, and decreased CCK pro-tein concentration in the hypothalamus.CONCLUSION: PWC improves gastrointestinal mo-tor function in FD rats by decreasing the leptin con-centration in serum and the brain-gut axis, and by increasing the CCK concentration in gastrointesti-nal tissue. Our findings help to elucidate the mech-anism of FD and provide further insight into the pharmacokinetics of PWC. 展开更多
关键词 Pingwei capsule DYSPEPSIA Gastroin- testinal motility Brain-gut peptide Brain-gut axis
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Antiviral activity of Jinchai capsule against influenza virus 被引量:5
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作者 Juying Zhong Xiaolan Cui +2 位作者 Yujing Shi Yingjie Gao Hongxin Cao 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第2期200-204,共5页
OBJECTIVE:To evaluate the effect on influenza virus of Jinchai,a capsule made of Traditional Chinese Medicine.METHODS:Madin-darby canine kidney(MDCK) cells were infected with the FM1 strain of influenza virus A(subtyp... OBJECTIVE:To evaluate the effect on influenza virus of Jinchai,a capsule made of Traditional Chinese Medicine.METHODS:Madin-darby canine kidney(MDCK) cells were infected with the FM1 strain of influenza virus A(subtype H1N1) in vitro.They were used to explore how Jinchai affected cell adsorption,cell membrane fusion,transcription and replication of the influenza virus.Hemagglutinin(HA) protein,intracellular pH,and influenza virus protein acid(PA) polymerase subunit were detected with confocal microscopy and real-time fluorescent quantitative polymerase chain reaction.RESULTS:Jinchai significantly reduced the expression of HA and PA polymerase subunit mRNA in infected MDCK cells.Jinchai also significantly decreased intracellular pH in infected cells.CONCLUSIONS:Jinchai had strong anti-influenza activity against the influenza virus.It weakened the ability of the influenza virus to adsorb to cell wall and fuse with cell membranes in the early infection stage,and inhibited the transcription and replication of the virus. 展开更多
关键词 Antiviral agents Influenza A virus Jin-chai capsule
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