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131.
1IntroductionItiswelknownthatbosonrealizationapproachisveryefectivetostudytherepresentationtheoryofgroup,andthebosonrealizat...  相似文献   
132.
Theinvestigationofproteinrenaturation,orrefoldinghasbecomeaveryhotpointinbothliquidchromatography(LC)andlifesciencefields.Besidesusualdilutionanddialysismethods,manynewmethodsconcernproteinrenaturationhavebeenpresented,suchasreversemicelles1,chaperones2,polyethyleneglycol(PEG)3,surfactant4andantibodies5etc.Oneoftheauthorssuggestedhighperformancehydrophobicinter-actionchromatography(HPHIC)tobeanewtoolforproteinrenaturation6.Areviewonproteinrenaturationwithliquidchromatography(LC)wasrecentl…  相似文献   
133.
本文研究了常规苯乙烯乳液和苯乙烯细乳液在两种不同冷冻条件下,即液氮冷冻和-20℃冰箱冷冻过程中乳液体系稳定性的变化,以及γ射线辐射引发冷冻乳液中单体聚合得到的聚苯乙烯微球的形貌,并探讨了形貌形成机制.结果表明,乳液在-20℃冰箱中冷冻过程中乳液稳定性破坏,单体出现分层现象.而液氮冷冻可以保持冷冻前的乳液相态结构.γ射线辐射可以引发冻乳液中苯乙烯聚合,聚合过程中体系经历了从O/W乳液向W/O/W多重乳液的转变,最终形成粒径分布较宽,直径为1~20μm的泡孔状多孔PS微球.本工作不仅为低温聚合技术提供了新思路,也为多孔聚合物微球材料的制备提供了新方法.  相似文献   
134.
(-) Clausenamide (1) showed strong nootropic action, while its (+) antipode had no such an action. The content of CM1(2) in the metabolites of (-)1 is much higher than that of (+)11. For comparing the nootropic activity of enantiomers, (+) and (-) CM1 were synthesized. CM1 is the hydroxylated product of the N-methyl group of clausenamide. Oxidation of the C3-OH and C6-OH protected clausenamide to introduce the hydroxyl group into the methyl was tried but unsuccessful. Then de novo s…  相似文献   
135.
StudiesonHepatocyte┐TargetingMagneticResonanceImagingMacromolecularContrastMedia*FUYan-junandZHUORen-xi**(DepartmentofChemist...  相似文献   
136.
STUDY ON THE SYNTHESIS AND PHYSICOCHEMICAL PROPERTIES OF SUCROSE POLYESTER   总被引:2,自引:0,他引:2  
1. INTRODUCTIONSucrose polyester (SPE) is neither metabolized nor absorbed, it makes no caloric contribution to the diet. Excessive dietary fat intake is associated with increasing risk of obesity, high blood cholesterol, hypertension, coronary heart disease and some types of cancer. At present, fat substitutes are fashionable all over the world. SPE is a new functional fat substitute, which is similar to ordinary oils in physical and chemical properties. In a word, the research and dev…  相似文献   
137.
CA15-3 is a circulating antigen that is relatively specific for human breast tissue. CA15-3 is significantly more sensitive than carcinoembryonic antigen in the evaluation of patients with both primary and metastatic breast cancer. CA15-3 levels are often measured by using radioimmunoassay and enzyme immunoassay (EIA) in clinic. These methods are carried out manually. Tedious processes, slow reaction, poor reproducibility are their major problems. Capillary electrophoretic immunoassay …  相似文献   
138.
Hydroxyethyl starches (HES) have been used medically as plasma volume expanders. They are composed of a starch backbone and substituted hydroxyethyl groups. The backbone is ?(1,4)-glycosidic-linked anhydroglucose units, which has branches formed by ?(1,6)-glycosidic bonds. Hydroxyethylation can take place at the C-2, C-3 and C-6 sites of the glucose rings, as well as at the hydroxyl groups of the substituted hydroxyethyl groups. Variation of the position and quantity of the substituted …  相似文献   
139.
Polyaniline, especially its acid-dopping composite material, is a kind of important photoelectric material due to its potential application in many fields1~3. However, it seems to be a problem that the polymers exhibit several deficiencies, including chemical and structural imperfections as a result of mislinkage, saturated sites, molecular weight distribution, the presence of the end groups and conformation defects. All of these defects affect the device efficiency and make it difficult to …  相似文献   
140.
Introduction Gastriccancerisoneofthemostcommonlyen counteredmalignantdiseasesworldwide,especiallyin AsiaandAfrica[1].Thecombinationofoperation,chemotherapyandradiotherapyisusedfortreatinggas triccarcinoma.However,the5yearsurvivalrateof patientsofgastricca…  相似文献   
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