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Changes of plasma D(-) -lactate, diamine oxidase and endotoxin in patients with liver cirrhosis 被引量:31
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作者 Peng Ruan, Zuo-Jiong Gong and Quan-Rong Zhang Wuhan, China Department of Infectious Diseases, Renmin Hospital Wuhan University Medical College, Wuhan 430060 , China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2004年第1期58-61,共4页
BACKGROUND: Plasma D(-)-lactate and diamine oxidase (DAO) can reflect patients' intestinal mucosal condition. We evaluated the changes of plasma D (-)-lactate, DAO and endotoxin activities and their significance i... BACKGROUND: Plasma D(-)-lactate and diamine oxidase (DAO) can reflect patients' intestinal mucosal condition. We evaluated the changes of plasma D (-)-lactate, DAO and endotoxin activities and their significance in patients with liver cirrhosis. METHODS: Fifty liver cirrhosis patients were enrolled into experimental group and 30 healthy people into control group. The plasma levels of D(-)-lactate, DAO and endo- toxin were detected spectrophotographically. RESULTS: The level of D(-)-lactate was significantly high- er in the experimental group than that in the control group (P<0.01). Significant differences of D (-)-lactate levels were observed in Child-Pugh subgroups of the experimen- tal group (P <0. 01). The level of DAO was significantly higher in the experimental group than that in the control group (P <0.01), but the level of DAO in Child-Pugh sub- group C was significantly lower than that in Child-Pugh subgroup B (P<0.01). The level of endotoxin was signifi- cantly increased in the experimental group except Child Pugh subgroup A (P<0.01). The plasma levels of D(-) lactate, DAO and endotoxin were positively correlated with each other (P<0.01). CONCLUSIONS: The data suggest that both plasma D(-) lactate and DAO activity are sensitive markers for early diagnosis of gut failure and endotoxemia in patients with liver cirrhosis. The impairment of intestinal barrier func- tion may be one of the critical reasons for deterioration of liver cirrhosis. 展开更多
关键词 liver cirrhosis D(-)-lactate diamine oxidase ENDOTOXIN intestinal permeability gut failure
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聚脲的合成与应用 被引量:29
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作者 浦鸿汀 刘泰 +1 位作者 杨正龙 袁俊杰 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2008年第7期1-5,共5页
聚脲主要通过二异氰酸酯和二胺或二异氰酸酯和水反应聚合得到,聚合方式主要有直接聚合、溶液聚合、乳液聚合、气相沉积聚合等。文中综述了聚脲较新的研究进展,讨论了反应注塑与喷涂聚脲弹性体、聚脲微胶囊、聚脲气相沉积聚合等应用,并... 聚脲主要通过二异氰酸酯和二胺或二异氰酸酯和水反应聚合得到,聚合方式主要有直接聚合、溶液聚合、乳液聚合、气相沉积聚合等。文中综述了聚脲较新的研究进展,讨论了反应注塑与喷涂聚脲弹性体、聚脲微胶囊、聚脲气相沉积聚合等应用,并展望了聚脲的研究和应用前景。 展开更多
关键词 聚脲 二异氰酸酯 二胺
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新型大环席夫碱化合物的合成及其抗菌活性研究 被引量:28
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作者 袁泽利 胡庆红 +2 位作者 吴庆 张铭钦 朱必学 《有机化学》 SCIE CAS CSCD 北大核心 2009年第2期279-282,共4页
利用Ca2+,Ba2+离子作为模板离子,由2,4-二羟基-5-乙酰苯乙酮与烷基二胺[即1,3-丙二胺,1,4-丁二胺,1,6-己二胺]反应,分别合成了系列新型席夫碱大环化合物Ln(n=3,4,6).对合成得到的新型大环席夫碱化合物采用元素分析,1HNMR,IR,紫外-可见... 利用Ca2+,Ba2+离子作为模板离子,由2,4-二羟基-5-乙酰苯乙酮与烷基二胺[即1,3-丙二胺,1,4-丁二胺,1,6-己二胺]反应,分别合成了系列新型席夫碱大环化合物Ln(n=3,4,6).对合成得到的新型大环席夫碱化合物采用元素分析,1HNMR,IR,紫外-可见光谱和MS等进行组成和结构表征,体外抗菌活性也被试验. 展开更多
关键词 烷基二胺 模板合成法 席夫碱 抗菌活性
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血清二胺氧化酶测定的临床应用进展 被引量:29
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作者 侯玥 宫平 +1 位作者 杨羽 于源华 《中国实验诊断学》 2015年第11期1985-1986,F0003,共3页
二胺氧化酶(diamine oxidase;DAO,E.C.1.4.3.6)是存在于哺乳动物小肠的黏膜或纤毛上皮细胞中催化二胺的细胞内酶,它可通过调节细胞内的离子平衡、影响传导通路、促进细胞修复,对肠黏膜具有保护作用[1]。小肠黏膜屏障功能衰竭时或肠黏... 二胺氧化酶(diamine oxidase;DAO,E.C.1.4.3.6)是存在于哺乳动物小肠的黏膜或纤毛上皮细胞中催化二胺的细胞内酶,它可通过调节细胞内的离子平衡、影响传导通路、促进细胞修复,对肠黏膜具有保护作用[1]。小肠黏膜屏障功能衰竭时或肠黏膜细胞坏死时血清DOA升高,因此,血液中的DOA活性可反映肠道损伤状态[2,3]。 展开更多
关键词 血清二胺氧化酶 小肠黏膜 慢性荨麻疹 多器官功能障碍 纤毛上皮细胞 先兆流产 细胞内酶 diamine 屏障功能 细胞修复
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Functional changes of intestinal mucosal barrier insurgically critical patients 被引量:25
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作者 Yuan-yuanGuo Mu-linLiu +2 位作者 Xian-di He Cong-qiao Jiang Rui-lin Liu 《World Journal of Emergency Medicine》 SCIE CAS 2010年第3期205-208,共4页
BACKGROUND: The gut is capable of inducing multiple organ dysfunction syndrome (MODS). In the diagnosis and treatment of critical ill patients, doctors should pay particular attention to the protection or recovery ... BACKGROUND: The gut is capable of inducing multiple organ dysfunction syndrome (MODS). In the diagnosis and treatment of critical ill patients, doctors should pay particular attention to the protection or recovery of intestinal barrier function. However, no reliable diagnostic criteria are available clinically. This study aimed to assess the changes of intestinal mucosal barrier function in surgically critical ill patients as well as their signi? cance.METHODS: Thirty-eight surgically critical ill patients were enrolled as a study group (APACHE II〉8 scores), and 15 non-critical ill patients without intestinal dysfunction were selected as a control group (APACHE II〈6). General information, symptoms, physical signs, and APACHE II scores of the patients were recorded. The patients in the study group were subdivided into an intestinal dysfunction group (n=26) and a non-intestinal dysfunction group (n=12). Three ml venous blood was collected from the control group on admission and the same volume of plasma was collected from the study group both on admission and in the period of recovery. The plasma concentrations of endotoxin, diamine oxidase (DAO), D-lactate, and intestinal fatty-acid binding protein (iFABP) were detected respectively. The data collected were analyzed by the SPSS 17.0 software for Windows. RESULTS: The levels of variables were significantly higher in the study group than in the control group (P〈0.01). They were higher in the intestinal dysfunction group than in the non-intestinal dysfunction group (DAO P〈0.05, endotoxin, D-lactate, iFABP P〈0.01). In the non-intestinal dysfunction group compared with the control group, the level of endotoxin was not significant (P〉0.05), but the levels of DAO, D-lactate and iFABP were statistically significant (P〈0.05). The levels of variables in acute stage were higher than those in recovery stage (P〈0.01).The death group showed higher levels of variables than the survival group (endotoxin a 展开更多
关键词 Intestinal mucosal barrier ENDOTOXIN diamine oxidase D-LACTATE Intestinal fatty-acid binding protein
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Soluble intercellular adhesion molecule-1,D-lactate and diamine oxidase in patients with inflammatory bowel disease 被引量:23
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作者 Wei-Bing Song Yong-Hui Lv +6 位作者 Zhen-Shu Zhang Ya-Nan Li Li-Ping Xiao Xin-Pei Yu Yuan-Yuan Wang Hong-Li Ji Li Ma 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第31期3916-3919,共4页
AIM: To study the levels of serum soluble intercellular adhesion molecule-1 (sICAM-1), plasma D-lactate and diamine oxidase (DAO) in patients with inflammatory bowel disease (IBD), and the potential clinical si... AIM: To study the levels of serum soluble intercellular adhesion molecule-1 (sICAM-1), plasma D-lactate and diamine oxidase (DAO) in patients with inflammatory bowel disease (IBD), and the potential clinical significance. METHODS: Sixty-nine patients with IBD and 30 healthy controls were included in this study. The concentration of sICAM-1 was detected with enzyme-linked immunosorbent assay, the level of D-lactate and DAO was measured by spectroscopic analysis, and the number of white blood cells (WBC) was determined by routine procedure. RESULTS: The levels of sICAM-I, DAO, and WBC in IBD patients were significantly higher than those in the control group (P 〈 0,01), sICAM-I in IBD patients was found to be closely related to the levels of DAO and D-lactate (212.94 ± 69.89 vs 6.35 ± 2.35, P = 0.000), DAO 212.94 ± 69.89 vs 8.65 ± 3.54, P = 0.000) and WBC (212.94 ± 69.89 vs 7.40 ± 2.61, P = 0.000), but no significant difference was observed between patients with ulcerative colitis and patients with Crohn's disease. The post-treatment levels of sICAM-I, D-lactate and WBC were significantly lower than before treatment (sICAM-I 206.57 ± 79.21 vs 146.21 ± 64.43, P = 0.000), (D-lactate 1.46 ± 0.94 vs 0.52± 0.32, P = 0.000) and (WBC 7.24 ± 0.2.33 vs 5.21 ± 3.21, P = 0.000). CONCLUSION: sICAM-1, D-lactate and DAO are closely related to the specific conditions of IBD, and thus could be used as a major diagnostic index. 展开更多
关键词 Inflammatory bowel diseases Intercellular adhesion molecule-1 D-LACTATE diamine oxidase
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乙二胺和己二胺氨基功能化氧化石墨烯(英文) 被引量:15
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作者 闫家林 陈贵娇 +3 位作者 曹君 杨伟 谢邦互 杨鸣波 《新型炭材料》 SCIE EI CAS CSCD 北大核心 2012年第5期370-376,共7页
采用了一种通过采用乙二胺和己二胺接枝改性制备氨基功能化石墨烯的高效、经济的方法。结果表明,该方法可对氧化石墨烯进行有效的氨基化,且官能化程度较高,每9~10个碳原子中就有一个参与氨基化反应;随着二元胺烷基链长度的增长,氨基功... 采用了一种通过采用乙二胺和己二胺接枝改性制备氨基功能化石墨烯的高效、经济的方法。结果表明,该方法可对氧化石墨烯进行有效的氨基化,且官能化程度较高,每9~10个碳原子中就有一个参与氨基化反应;随着二元胺烷基链长度的增长,氨基功能化氧化石墨烯的的热稳定性得到明显提高,但在N,N-二甲基甲酰胺溶剂中的分散性却会变差。 展开更多
关键词 石墨烯 氧化石墨烯 氨基功能化 二元胺
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N-(2-氰基乙基)丁胺的合成研究 被引量:15
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作者 陈朝阳 钟宏 《化学工程师》 CAS 2002年第5期12-14,共3页
以甲苯和异丙醇的混合溶液作溶剂 ,正丁胺与丙烯腈反应合成N - (2 -氰基乙基 )丁胺 ;研究了溶剂种类和用量 ,原料配比 ,反应温度及时间对正丁胺转化率、N - (2 -氰基乙基 )丁胺选择性、单程总收率的影响 ;最佳工艺条件为 :溶剂为混合溶... 以甲苯和异丙醇的混合溶液作溶剂 ,正丁胺与丙烯腈反应合成N - (2 -氰基乙基 )丁胺 ;研究了溶剂种类和用量 ,原料配比 ,反应温度及时间对正丁胺转化率、N - (2 -氰基乙基 )丁胺选择性、单程总收率的影响 ;最佳工艺条件为 :溶剂为混合溶剂 [m(甲苯 ) :m(异丙醇 ) =2 0 ],m(溶剂 ) :m(正丁胺 ) =4 0~5 0 ,n(丙烯腈 ) :n(丙烯腈 ) :n(正丁胺 ) =1 0 ,反应温度为 5 0~ 6 0℃ ,丙烯腈滴加时间 4 5min ,保温反应时间90min ;单程总收率可达 84 3% ,产品纯度可达 98 0 %以上。 展开更多
关键词 N-(2-氰基乙基)丁胺 合成 研究 β-正丁胺基丙腈 氰乙基化反应 二胺 多胺
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三种新型二胺的合成研究 被引量:9
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作者 吉保明 陈花婷 《化学研究与应用》 CAS CSCD 1999年第6期673-675,共3页
This paper reports the reduction of 1,3-bis(2-nitro phenoxy)-2-propanol,1,3-bis(nitrophenoxy)-2-propanol and 1,3-bis(4-nitrophenoxy)-2-propanol to the corresponding diamine by the NH 2NH 2·H 2O-FeCl 3·6H 2O-... This paper reports the reduction of 1,3-bis(2-nitro phenoxy)-2-propanol,1,3-bis(nitrophenoxy)-2-propanol and 1,3-bis(4-nitrophenoxy)-2-propanol to the corresponding diamine by the NH 2NH 2·H 2O-FeCl 3·6H 2O-C system.All these diamine compounds were identified by elemental analysis,IR spectra, 1HNMR and MS. 展开更多
关键词 二硝基化合物 二胺 还原 合成
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聚酰亚胺的发展动向,机遇和对策 被引量:11
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作者 贺飞峰 《上海化工》 CAS 2004年第8期28-31,共4页
介绍了聚酰亚胺的发展历史以及它的应用,并归纳了国外发展的动向和研究方向;对国内聚酰亚胺领域的现状和与国外的差距进行了分析,就此提出了相应的对策,抓住当前的机遇,来加快我国聚酰亚胺的发展。
关键词 聚酰亚胺 二酐 二胺 应用 品种 质量 中国
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双马/二元胺/环氧体系的组成对性能的影响 被引量:8
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作者 王汝敏 《高分子材料科学与工程》 EI CAS CSCD 北大核心 1997年第3期73-78,共6页
以普通的4,4′-二氨基二苯甲烷双马来酰亚胺为基础,用二元胺和环氧树脂进行改性。着重研究了不同结构的二元胺和环氧树脂及其用量对改性双马树脂及复合材料性能的影响。结果表明,DDS改性体系的耐热性优于DDE改性体系,但其... 以普通的4,4′-二氨基二苯甲烷双马来酰亚胺为基础,用二元胺和环氧树脂进行改性。着重研究了不同结构的二元胺和环氧树脂及其用量对改性双马树脂及复合材料性能的影响。结果表明,DDS改性体系的耐热性优于DDE改性体系,但其预聚物丙酮溶解性差于DDE预聚物。BMI/二元胺摩尔比高的改性树脂耐热性高,但韧性低,丙酮溶解性差。不同结构的环氧改性双马树脂耐热性相差不大,但环氧的结构对双马改性环氧树脂的耐热性、韧性影响较大。环氧用量增加,工艺性改善,但耐热性下降。20%~30%环氧改性的双马树脂仍具有较高的耐热性,热变形温度高于280℃,150℃、200℃、250℃下复合材料的弯曲和剪切强度保持率较高。 展开更多
关键词 双马来酰亚胺 二元胺 环氧树脂 结构与性能
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氨基化多壁碳纳米管的制备及其在复合材料中的应用 被引量:10
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作者 王国建 祖梅 邱军 《新型炭材料》 SCIE EI CAS CSCD 北大核心 2011年第2期89-97,共9页
采用不同链长的乙二胺(EDA)、己二胺(HMDA)和癸二胺(DMDA)对多壁碳纳米管(MW CNTs)进行了修饰。利用红外光谱、拉曼光谱、透射电镜及X射线光电子能谱对二元胺修饰的MW CNTs的化学结构进行了表征。结果表明:二元胺可以有效地修饰MW CNTs... 采用不同链长的乙二胺(EDA)、己二胺(HMDA)和癸二胺(DMDA)对多壁碳纳米管(MW CNTs)进行了修饰。利用红外光谱、拉曼光谱、透射电镜及X射线光电子能谱对二元胺修饰的MW CNTs的化学结构进行了表征。结果表明:二元胺可以有效地修饰MW CNTs。经胺化修饰后,MW CNTs-EDA、MW CNTs-HMDA、MW CNTs-DMDA表面的N元素含量可分别达到3.52%、4.18%和2.88%,表明在相同的氨化条件下,己二胺的接枝率最高。进一步采用紫外-可见吸收光谱及全能稳定性分析仪对不同链长的二元胺修饰的氨基化MW CNTs在有机溶剂中的分散性进行了半定量的表征。结果显示:氨基化修饰有效改善了碳纳米管在极性溶剂中的分散稳定性,其中己二胺修饰的MW CNTs在乙醇中的分散稳定性最好。将MW CNTs-HMDA引入到传统的炭纤维/环氧树脂复合材料体系中,复合材料的冲击性能及弯曲性能均有较大提高。 展开更多
关键词 碳纳米管 二元胺 化学修饰 分散稳定性 复合材料
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Possible relationship between intestinal barrier function and formation of pigment gallstones in hamsters 被引量:8
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作者 Fan, Ying Wu, Shuo-Dong +2 位作者 Sun, Lei Fu, Bei-Bei Su, Yang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2008年第5期529-532,共4页
BACKGROUND: The presence of bacteria in bile is an important factor in the formation of pigment gallstones. The bile of healthy people is sterile and bacteria in the biliary system come from endogenous infection from ... BACKGROUND: The presence of bacteria in bile is an important factor in the formation of pigment gallstones. The bile of healthy people is sterile and bacteria in the biliary system come from endogenous infection from the gut. Yet, the route of bacterial translocation into the bile duct is still unclear. Theoretically, two routes exist: one is through the intestinal barrier and the other is by direct reflux from the sphincter of Oddi. This study was undertaken to explore the relationship between the effectiveness of intestinal barrier and the formation of pigment gallstones in hamsters. METHODS: Thirty-two hamsters were divided into an experimental and a control group, with 16 hamsters in each group. A low protein and high cellulose diet was given for 6 weeks to induce the formation of pigment gallstones in the experimental group (PS) and a normal diet was given to the control group (CON). Morphological changes, changes in the levels of serum endotoxin and diamine oxidase, and changes in the numbers of B lymphocytes, plasma cells and secretory immunoglobin A (sIgA) in the intestinal mucosa were assessed after 6 weeks. RESULTS: Four hamsters died during lithogenesis and body weight decreased in the PS group. Pigment gallstones were found in 11 hamsters at the end of the experiment, giving a lithogenesis rate of 91.67%. The serum endotoxin level before and after gallstone formation in the PS group was 0.2960 +/- 0.1734 U/ml and 8.2964 +/- 4.6268 U/ml, respectively (P<0.05). The blood diamine oxidase level before and after gallstone formation in the PS group was 2.6333 +/- 0.8037 U/ml and 3.3642 +/- 0.9545 U/ml, respectively (P<0.05). The numbers of B lymphocytes, plasma cells and sIgA in the intestinal mucosa in the PS group were 71.56 +/- 2.89, 68.65 +/- 2.09 and 27.56 +/- 1.07, respectively, and were significantly decreased compared with the corresponding values in the CON group (94.25 +/- 3.69, 93.47 +/- 3.98 and 42.57 +/- 1.96, respectively, P<0.05). CONCLUSIONS: A low protein and high cellulose diet can markedl 展开更多
关键词 ENDOTOXINS diamine oxidase B lymphocytes plasma cells secretory immunoglobin A
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Controversies about the use of serological markers indiagnosis of in flammatory bowel disease 被引量:8
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作者 Xie, Qin Gan, Hua-Tian 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第2期279-280,共2页
The serological markers are increasingly used in diagnosis of inflammatory bowel disease(IBD).D-lactate and diamine oxidase are new indicators that can be used to reveal the damage to intestinal mucosa and permeabilit... The serological markers are increasingly used in diagnosis of inflammatory bowel disease(IBD).D-lactate and diamine oxidase are new indicators that can be used to reveal the damage to intestinal mucosa and permeability alteration in IBD.Although the two biological markers seem more sensitive,recent clinical trials and animal experiments have shown controversies about the use of them in diagnosis of IBD.Therefore, these markers should be interpreted cautiously and further prospective studies are needed to establish their clinical role in diagnosis of IBD. 展开更多
关键词 Inflammatory bowel diseases D-LACTATE diamine oxidase Intestinal permeability DIAGNOSIS
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铝硅酸盐矿物捕收剂的设计研究 被引量:9
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作者 彭兰 曹学锋 杜平 《广西民族学院学报(自然科学版)》 CAS 2005年第2期90-93,共4页
铝硅酸盐矿物是层状硅酸盐矿物,破碎后晶体端面荷电是表面原子的选择性吸附和解离而成,并随pH变化而变化,其层面荷电为金属离子的晶格取代造成,荷永久负电荷,不随溶液pH值变化而改变.阳离子捕收剂是铝硅酸盐矿物捕收剂的设计首选.多胺... 铝硅酸盐矿物是层状硅酸盐矿物,破碎后晶体端面荷电是表面原子的选择性吸附和解离而成,并随pH变化而变化,其层面荷电为金属离子的晶格取代造成,荷永久负电荷,不随溶液pH值变化而改变.阳离子捕收剂是铝硅酸盐矿物捕收剂的设计首选.多胺类药剂与十二胺相比增加了吸附活性点,浮选性能得到改善.有关参数的计算结果说明多胺类药剂是比十二胺更佳的铝硅酸盐矿物捕收剂.浮选试验也证实这一结论. 展开更多
关键词 铝硅酸盐 反浮选 荷电原理 阳离子捕收剂 多胺
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高级脂肪胺及其衍生物的应用前景 被引量:10
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作者 刘志勤 王亚光 连工宝 《精细与专用化学品》 CAS 2007年第22期4-7,16,共5页
简要介绍高级脂肪胺的种类、合成路线及性能。重点综述了高级脂肪伯胺和叔胺的应用,主要是在制备阳离子表面活性剂、非离子表面活性剂和两性表面活性剂等方面的应用;同时概述了仲胺、二胺、多胺及其衍生物的应用。最后对高级脂肪胺及其... 简要介绍高级脂肪胺的种类、合成路线及性能。重点综述了高级脂肪伯胺和叔胺的应用,主要是在制备阳离子表面活性剂、非离子表面活性剂和两性表面活性剂等方面的应用;同时概述了仲胺、二胺、多胺及其衍生物的应用。最后对高级脂肪胺及其衍生物的发展提出了几点建议。 展开更多
关键词 高级脂肪胺 伯胺 仲胺 叔胺 二胺
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双马来酰亚胺树脂增韧改性研究进展 被引量:9
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作者 张思 张扬 张宝艳 《科技导报》 CAS CSCD 北大核心 2016年第8期31-34,共4页
综述了双马来酰亚胺树脂的基本性能,分析了增韧改性的意义。目前双马来酰亚胺树脂增韧改性的主要方法包括与烯丙基化合物共聚、二元胺增韧、环氧树脂增韧、热塑性树脂增韧、氰酸酯增韧、合成新型双马来酰亚胺树脂单体、橡胶增韧改性、... 综述了双马来酰亚胺树脂的基本性能,分析了增韧改性的意义。目前双马来酰亚胺树脂增韧改性的主要方法包括与烯丙基化合物共聚、二元胺增韧、环氧树脂增韧、热塑性树脂增韧、氰酸酯增韧、合成新型双马来酰亚胺树脂单体、橡胶增韧改性、无机填料增韧改性、液晶增韧改性、纳米材料增韧改性及柔性材料增韧改性等。双马来酰亚胺树脂增韧改性的机理包括加成反应、Diels-Alder反应、齐聚反应、Michael加成反应、共聚反应、裂纹钉锚机制及半互穿网络机制等。论述了国内外对于双马来酰亚胺树脂增韧改性的研究现状,探讨了该方向的研究趋势。 展开更多
关键词 双马来酰亚胺树脂 增韧方法 增韧机理 二元胺 环氧树脂
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Stoichiometry and Stability Constant Values for Copper (II) Chelates with Ethylene Diamine in Deep Eutectic Solvents (DES) (Ethaline) Solutions
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作者 Khalid El Ttaib Abdolhadi Benhmid Rifat Hasan Omar 《Open Journal of Applied Sciences》 2024年第9期2592-2609,共18页
In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements ha... In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements have been applied for establishing, the stoichiometry and whenever possible, the stability constants of the chelates formed. The method of continuous variations was necessary to determine first whether, the metal ion and the ligand ethylene diamine form one or more than one chelate, when more than one chelate formed, the results obtained depend on the wavelength and for meaningful conclusions the wavelengths were carefully selected. The empirical formulae of the chelates were further substantiated by the molar ratio method. The effect of time and temperature on the formation and stability of these chelates in solution is also studied. The stability constants, K1 and K2 for the copper (II) chelates were calculated, though reliable, and are comparable to literature values. 展开更多
关键词 CU(II) Ethylene diamine (en) Deep Eutectic Solvents Job’s Method Ionic Liquids and Stability Constant
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Soluble Fiber Improves Management of Diarrhea in Elderly Patients Receiving Enteral Nutrition 被引量:6
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作者 Yoshiaki Kato Makoto Nakao +2 位作者 Motoh Iwasa Shizuo Hasegawa Kiyofumi Yamada 《Food and Nutrition Sciences》 2012年第11期1547-1552,共6页
Dietary fiber is a non-digestible carbohydrate providing beneficial effects for bowel health. The aim of this study was to evaluate the clinical effects of fiber supplementation in enteral feeding on elderly patients ... Dietary fiber is a non-digestible carbohydrate providing beneficial effects for bowel health. The aim of this study was to evaluate the clinical effects of fiber supplementation in enteral feeding on elderly patients suffering from diarrhea. This study was conducted in 15 patients (7 men and 8 women, 79.0 ± 7.5 years) who had loose stools or diarrhea during enteral nutrition. The enteral formula was supplemented with soluble dietary fiber (5.2 g/day) for 3 weeks, which was then discontinued for 1 week to confirm its effects. The effects of soluble dietary fiber on stool frequency, the Bristol Stool Form Scale (which is designed to measure stool consistency), plasma diamine oxidase (DAO) activity, and concentrations of plasma short-chain fatty acids (SCFA) were evaluated. After supplementation with soluble dietary fiber, there were no significant differences in stool frequency but there was a significant improvement in stool consistency (P < 0.05). Furthermore, ingestion of soluble dietary fiber resulted in increased plasma DAO activity and significantly increased levels of plasma SCFA (P < 0.05). Supplementation with soluble dietary fiber may be beneficial for improving stool consistency in patients suffering from diarrhea during enteral nutrition. A further controlled trial is warranted to examine the preventive effects of soluble dietary fiber in patients suffering from diarrhea. 展开更多
关键词 ENTERAL Nutrition Soluble Dietary Fiber DIARRHEA PLASMA Short-Chain FATTY Acids PLASMA diamine OXIDASE Elderly Patients
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Effects of cardiopulmonary bypass on tight junction protein expressions in intestinal mucosa of rats 被引量:8
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作者 Ying-Jie Sun Wei-Min Chen +2 位作者 Tie-Zheng Zhang Hui-Juan Cao Jin Zhou 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第38期5868-5875,共8页
AIM: To investigate the tight junction protein expressions of intestinal mucosa in an experimental model of cardiopulmonary bypass (CPB) in rats. METHODS: Thirty anesthetized rats were randomly divided into two gr... AIM: To investigate the tight junction protein expressions of intestinal mucosa in an experimental model of cardiopulmonary bypass (CPB) in rats. METHODS: Thirty anesthetized rats were randomly divided into two groups: Group S (n = 10) served as sham operation and group C (n = 20) served as CPB which underwent CPB for 1 h. Expression of occludin and zonula occludens-1 (ZO-1) were determined by Western blotting and immunotochemistry, respectively. Plasma levels of diamine oxidase (DAO) and d-lactate were determined using an enzymatic spectrophotometry. RESULTS: Immunohistochemical localization of occludin and ZO-1 showed disruption of the tight junctions in enterocytes lining villi at the end of CPB and 2 h after CPB. The intensities of the occludin and ZO-i at the end of CPB were lower than those of control group (76.4% ± 22.5% vs 96.5% ± 28.5% and 62.4% ± 10.1% vs 85.5% ±25.6%, P 〈 0.05) and were further lower at 2 h after CPB (50.5% ± 10.5% and 45.3% ± 9.5%, P 〈 0.05). Plasma d-lactate and DAO levels increased significantly (8.688 ± 0.704 vs 5.745 ± 0.364 and 0.898 ± 0.062 vs 0.562 ± 0.035, P 〈 0.05) at the end of CPB compared with control group and were significantly higher at 2 h after CPB than those at the end of CPB (9.377 ± 0.769 and 1.038 ± 0.252, P 〈 0.05). There were significant negative correlations between occludin or ZO-1 expression and DAO (r^2 = 0.5629,r^2 = 0.5424, P 〈 0.05) or d-lactate levels (r^2 = 0.6512,r^2 = 0.7073, P 〈 0.05) both at the end of CPB and 2 h after CPB. CONCLUSION: CPB markedly down-regulates the expression of occludin and ZO-1 proteins in intestinal mucosa of rats. The close correlation between expression of tight junctions (TJs) and plasma levels of DAO or d-lactate supports the hypothesis that intestinal permeability increases during and after CPB because of decreases in the expressions of TJs. 展开更多
关键词 Cardiopulmonary bypass OCCLUDIN ZO-1 Tight junction diamine oxidase D-LACTATE
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