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51.
辣根过氧化物酶对心肌线粒体过氧化损伤的保护作用 总被引:1,自引:0,他引:1
以黄嘌呤氧化酶/次黄嘌呤自由基诱生系统建立了稳定的离体心肌线粒体的损伤模型,并应用此模型研究辣根过氧化物酶对心肌线粒体自由基氧化损伤的保护作用,结果表明,辣根过氧化物酶能抑制心肌线粒体中氧自由基的形成,降低膜脂的过氧水平,保护了线粒体膜酶活性,有效地防止自由基对线粒体结构和功能的损伤。 相似文献
52.
Removal of Endotoxin from Human Serum Albumin Solutions by Hydrophobic and Cationic Charged Membrane 总被引:1,自引:0,他引:1
Removal of end6toxin from medicine injection is very important, becauseendotoxin withpotential biological activity causes pyrogenic and shock reactions in' mammals-'on...intravenous injection even as law as "an6gram amounts. Endotoxin, a constituent ofpotential contaminant of physiological fluids and aqueous solutions 'and very stable atextreme temperature and PH values. For removing endotoxin from solutions ofbiomolecules, such as HSA, adsorption techniques are usedl.' Many methods forendot… 相似文献
53.
L. -M. Yuan R. -N. Fu S. -H. Gui X. -T. Xie R. -J. Dai X. -X. Chen Q. -H. Xu 《Chromatographia》1997,46(5-6):291-294
Summary The gas chromatographic separation of xylene isomers using special mixed stationary phases consisting of heptakis(2.3.6-tri-O-pentyl)-β-CD-AgNO3, heptakis (2.3.6-tri-O-pentyl)-β-CD-TINO3 or bentone-34-AgNO3 is investigated. The first two have positive synergistic effects for the separation of m, and p-xylene isomers, but negative
synergistic effects for the m, and oisomers. The separation effects depend on temperature, mixing ratio and how mixing is
accomplished. 相似文献
54.
反相液相色谱用球形共聚物柱填料 总被引:2,自引:0,他引:2
采用新颖聚合工艺制备用于反相高效液相色谱柱填料的乙基苯乙烯-二乙烯苯球形共聚物,不需使用备有高速搅拌的混匀器和特殊的筛析设备,聚合物粒径的95%在3~7μm之间,测算了渗透性、柱效和峰不对称性等柱参数,并通过分离实例说明该填料对胺类、酚类和芳烃类具有优良分离性能。 相似文献
55.
Wang Y Deng K Gui L Tang Y Zhou J Cai L Qiu J Ren D 《Journal of colloid and interface science》1999,213(1):270-272
Nanoscopic particles of oxovanadium phthalocyanine (VOPc, phase-II) with different particle sizes are prepared by aggregation of VOPc molecules in the presence of surfactants for the first time. A size effect in the region of nanoscale was observed in the UV-visible spectra. The photoconductivity of the nanoscopic VOPc is much higher than that of bulk VOPc. Copyright 1999 Academic Press. 相似文献
56.
苯基荧光酮荧光分光光度法测定痕量锗的研究 总被引:10,自引:0,他引:10
锗具有增血、抗炎症、抗衰老等多种医疗功能 ,因此 ,越来越受到人们的关注。荧光光度法测定微量锗已有报道[1~ 4] 。用苯基荧光酮荧光度法测定锗未见报道。本文利用苯基荧光酮与锗在醋酸 醋酸钠缓冲溶液中络合物形成速度快的优势 ,使其先在缓冲溶液中显色 ,然后在 0 .3mol LHCl介质中测定其荧光强度 ,用于粉煤灰中痕量锗的测定 ,得到满意结果。1 实验部分1 1 仪器与试剂RF - 5 4 0荧光分光光度计 (日本岛津 )。锗标准溶液 ( 1g L) :称取 0 .1 0 0 0g纯锗粉于 5 0ml小烧杯中 ,加入 5mlNaOH ,再加入几滴 30 %H2 O2… 相似文献
57.
Chang Xiu Han Ji Li Ren Xue Jiao Tang Bao Gui Zhang 《中国化学快报》2007,18(10):1285-1288
A new ternary Fe-based alloy catalyst FeCuP applied to decompose PH_3 was prepared with low-cost material by chemical reduction deposition method.The properties of it were characterized by XRD,ICP and SEM.Its catalytic activity on the decomposition of PH_3 and the decomposition conditions were studied.FeCuP alloy exhibits high thermal stabilities and high catalytic activity.Using it as catalyst,the decomposition temperature of phosphine decreases from over 800℃to 400-500℃.The decomposition rate of phosphine achieved 100%. 相似文献
58.
A facile approach to chiral dihydroquinazolinone derivatives has been described via biomimetic asymmetric reduction of quinazolinones with chiral and regenerable NAD(P)H models. The utility of this method was demonstrated by a concise synthesis of the bromodomain protein divalent inhibitor. 相似文献
59.
Zhen‐Yu Li Ping Chen Hong‐Gui Xu Shu‐Ying Peng Yi‐Ming Yang Zhong‐Zhen Zhao Yue‐Wei Guo 《Helvetica chimica acta》2007,90(7):1353-1359
Five new polycyclic Daphniphyllum alkaloids, macropodumines F ( 1 ) and G ( 2 ), 17‐oxoyuzurimine ( 3 ), and macropodumines H ( 4 ) and I ( 5 ), were isolated from the leaves of D. macropodum Miq ., collected in Sichuan Province, China. The structures and relative configurations of the new compounds – as well as of four known, related alkaloids – were elucidated on the basis of in‐depth spectroscopic and mass‐spectrometric analyses, by chemical derivatization, and by comparison of spectroscopic data with those of known compounds. 相似文献
60.
The present paper employed density function theory to investigate two reaction pathways for isomerization of enol ester proposed by Yang(path a) and the present authors(path a), respectively. The base catalytic effects of solvent triethylamine on these two reactions were also evaluated. It is demonstrated that path B is more preferable than path a due to low barrier height for the rate-determining step. 相似文献