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991.
992.
Purification and Characterization of an Antibacterial Peptide from Rana Temporaria Chensinensis Skin 总被引:1,自引:0,他引:1
GOU Xiao jun LI Xiang hui DING Tian bing WANG Yong ting CHEN Huai yong HUANG Cheng fang DONG Qing chu LI Qing shan * 《高等学校化学研究》1999,(4)
IntroductionInadditiontothehighlyspecificcell-mediatedimmunesystem,vertebratesandotherorganismshaveadefensesystemmadeupofdistinctgroupsofbroad-spectrumantibacterialpeptides[1—3].Antibacterialpeptidescanbeclassifiedintotwogroupsbasedonhavingdisul-fide… 相似文献
993.
1 INTRODUCTIONCopper( ) displays a wide diversity in its structural chemistry,the copper co-ordination number ranging from two to four.Procedures to synthesize copper( )complexes are of greatinterestbecause of the diversity of products resulting from al-mostthe same methodology.Ithaslong been accepted thatcopper( ) complexesarediamagnetic and provide no optical absorption bands( no d- d transition isencountered) for a copper( ) ion with a d10 configuration and no electron spin reso-n… 相似文献
994.
Fu She HAN Jian Qiang QU Xin ZHANG Meng Xian DING Lian Xun GAO* PCLCC State Key Laboratory of Polymer Physics Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 《中国化学快报》2000,11(12)
Previously, we have reported a novel type of polyimides prepared from 3,3(-dioxo-1,1((3H,3(H)spirobi[isobenzofuran]-5,6,5(,6(-dianhydride 1a and a variety of diamines1. Considering that a spiral compound is planar asymmetry2, we recently studied the resolution of 1, and thereof, synthesized the optically active polyimides. To our knowledge, optically active polyimides containing a planar asymmetric monomers have not been reported thus far. Cinchonidine and cinchonine base were proved to be an… 相似文献
995.
Numerical study of fast ion behavior in the presence of magnetic islands and toroidal field ripple in the EAST tokamak 下载免费PDF全文
A peculiar first orbit loss type was found apart from the normal ones when we use ORBIT code to simulate fast ion orbits in the EAST tokamak. Fast ion orbits were studied in the presence of toroidal field (TF) ripple and magnetohydro- dynamic (MHD) perturbations. We analyzed the properties of the drifted orbits in detail and compared their differences, finding that the combined effects of ripple and magnetic islands are much greater than the effects of either one of them alone. Then we investigated the orbitdeviations as a function of pitch angle in different radial positions. The modeling results demonstrate that the loss of trapped particles is mainly caused by the ripple, while MHD'perturbation mainly plays an important role in the passing particles. Furthermore we modeled the loss rate using different equilibriums. Results prove that a higher beta can indeed improve the confinement of fast ions, while a little change in the q profile can make the topologies of magnetic islands become quite different and results in quite different total particle losses. 相似文献
996.
997.
2-芳基乙酸及乙酸酯具有显著的生物生理活性[1],是合成异黄酮[2]、异喹啉[3]衍生物的重要原料.苯乙腈水解法、苯乙酰胺水解法都曾用于芳基乙酸的合成[4].二羰基化合物的直接芳基化是合成该类化合物的最直接有效的方法.这些方法一般需要过渡金属催化剂的催化和配体的参与[5]. 相似文献
998.
Yu ZHAO * Yuan Ling KU Shoei Sheng LEE* Laboratory of Phytochemistry Kunming Institute of Botany Chinese Academy of Sciences Kunming School of Pharmacy College of Medicine National Taiwan University Taipei 《中国化学快报》2000,11(12)
One of the strategies of bettering Alzheimer's Disease is focused on cholinergic compound based on the cholinergic hypothesis1. An important approach to cholinergic augmentation is administration of cholinesterase inhibitors such as Huperzine A2. Territrem B is a potent AChE inhibitor (IC50 47 nM, H. Zea AchE)3, and its inhibitory mechanism is totally different with the known AChE inhibitors4. In the last report we have described three routes of synthesizing Territrem B analogues, whic… 相似文献
999.
溶质迁移研究已成为水文地质等领域的一个重要研究课题。综述了溶质迁移研究进展,重点介绍了溶质迁移在地下水污染与防治、土壤盐碱化防治、海水入侵和咸水入侵防治等方面的研究现状,并指出应进一步研究的问题。 相似文献
1000.
HUO Rui SHI Yi XU Jun-jie YAN Fei Lü Shao-wu SU Jia-ming DUAN Yu-jing FAN Jia NING Bo CONG Deng-li YAN Gang-lin* LUO Gui-min WEI Jing-yan * . College of Pharmaceutical Science . Key Laboratory for Molecular Enzymology Engineering of the Ministry of Education . College of Life Science Jilin University Changchun P. R. China 《高等学校化学研究》2009,25(2)
Reactive oxygen species(ROS) plays a key role in human heart diseases.Glutathione peroxidase(GPX) functions as an antioxidant as it catalyzes the reduction of hydroperoxide.In order to investigate the antioxidant effect of human selenium-containing single-chain Fv(Se-scFv-B3),a new mimic of GPX,a model system of hydrogen peroxide(H2O2)-induced rat cardiac myocyte damage was established.The cardiac myocyte damage was characterized in terms of cell viability,lipid peroxidation,cell membrane integrity,and intracellular H2O2 level.The Se-scFv-B3 significantly reduced H2O2-induced cell damage as shown by the increase of cell viability,the decline of malondialdehyde(MDA) production,lactate dehydrogenase(LDH) release,and intracellular H2O2 level.So Se-scFvB3 may have a great potential in the treatment of human heart diseases induced by ROS. 相似文献