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951.
ZHAO Hai-feng WU Lei LU Ming HU Yu-lin HAN Xiao LI Zheng-qiang . Key Laboratory for Molecular Enzymology & Engineering Ministry of Education Jilin University Changchun P. R. China . Medical 《高等学校化学研究》2011,(3):450-454
Lipid-bound [VHb(406)] and lipid-free [VHb(402)] wide type Vitreoscilla hemoglobin were separated from E. coli BL21(DE3). The RZ is 3.30 for [VHb(406)] and 3.15 for [VHb(402)], respectively. VHb(406) shows a characteristic absorption band at 626 nm, while VHb(402) shows one at 644 nm, and it has more α-helix than VHb(402). Data of Raman spectra experiment shows under the excitation wavelength 488 nm, υ4 vibration of both VHb(402) and VHb(406) had a pure and strong signal at 1375 cm-1, which proves that iron... 相似文献
952.
研究了桂枝和桂皮醛对环丙沙星在小鼠体内分布的影响,并基于此探讨了桂枝作为引药使用的作用机制.实验中将小鼠分为三组,分别灌胃生理盐水、桂枝(50gkg-1)和桂皮醛(0.25mLkg-1),然后对三组小鼠尾静脉注射环丙沙星(20mgkg-1),并以荧光法测定不同时间点小鼠体内各组织中环丙沙星的浓度.结果显示桂枝、桂皮醛均促进了环丙沙星在四肢的分布,桂枝与桂皮醛组相对于生理盐水组可将环丙沙星在四肢的含量提高约40%~200%,证实了桂枝引药到达肢节的作用.桂枝与桂皮醛组对环丙沙星分布情况的影响没有显著性差异,说明桂皮醛很可能是发挥桂枝引药作用的主要物质. 相似文献
953.
研究了5种α,α‘-二氧代烯酮环二硫代缩酮类化合物的碳基、碳碳双键、碳硫等一些特征红外光谱,尤其着重研究了共轭体系下的各种特征谱带随化学结构而变化的规律。 相似文献
954.
ZHAO Xiao-ping JIN Ye-cheng ZENG Xing ZHANG Bo-li ZHANG Yu-feng .Tianjin State Key Laboratory of Modern Chinese Medicine Tianjin University of Traditional Chinese Medicine Tianjin P.R.China .College of Preclinical Medicine Zhejiang Chinese Medical University Hangzhou .College of Pharmaceutical Sciences Zhejiang University Hangzhou 《高等学校化学研究》2011,(4):562-565
In order to identify the potential nephrotoxic compounds in traditional Chinese medicine Lithospermum erythrorhizon,it was separated into serial fractions according to their polarities.An in vitro method was utilized to determine the nephrotoxicity of these fractions with the help of fluorescence image analysis.As a result,the primary fraction A05 and its secondary fractions C06 C09 and C12 C14 were found to have significant toxicity to LLC-PK1 cell line,as determined by the survive rate less than 20% after... 相似文献
955.
JIANG ZhiLiang LI JiShun WEN GuiQing LIU QingYe & LIANG AiHui School of Environment Resources Guangxi Normal University Guilin China College of Chemistry Bioengineering Guilin University of Technology China 《中国科学:化学》2010,(5)
The resonance scattering spectral technique has been established using the synchronous scanning technique on spectrofluorometry.Because of its advantages of simplicity,rapidity and sensitivity,it has been widely applied to analyses of proteins,nucleic acids and inorganic ions.This paper summarizes the application of immunonanogold and aptamer modified nanogold(AptAu) catalytic resonance scattering spectral technique in combination with the work of our group,citing 53 references. 相似文献
956.
We provide estimates on the degree of C l GV determinacy ( G is one of Mather’s groups R or K ) of function germs which are defined on analytic variety V and satisfies a non-degeneracy condition with respect to some Newton polyhedron. The result gives an explicit order such that the C l geometrical structure of a function germ is preserved after higher order perturbations, which generalizes the result on C l G triviality of function germs given by M.A.S.Ruas. 相似文献
957.
Yiwei Zhang Yuming Zhou Lihui Wan Mengwei Xue Yongzheng Duan Xuan Liu .School of Chemistry Chemical Engineering Southeast University Nanjing Jiangsu China .Biochemical Environmental Engineering College Nanjing Xiaozhuang University Nanjing 《天然气化学杂志》2011,20(6):639-646
Catalytic dehydrogenation of isobutane has recently received considerable attention because of the increasing demand for isobutene.In this study,the synergistic effect between Sn and K on PtSnK/γ-Al2O3 catalysts has been investigated by changing the content of Sn.It was found that with the presence of potassium,suitable addition of Sn could not only increase the metal dispersion,but also reduce the catalyst acidity.In these cases,the synergistic effect could also strengthen the interactions between the metal and support,which resulted in an increase in both catalytic activity and stability.In our experiments,Pt-0.6SnK/Al catalyst exhibited the lowest deactivation rate (12.4%) and showed a selectivity to isobutene higher than 94% at the isobutane conversion of about 45.3% after running the reaction for 6 h.However,with the excessive loading of Sn,surface property of active sites and the interactions between metal and support were changed.As a result,the initial optimal ratio between the metallic function and acid function would be destroyed,which was disadvantageous to the reaction. 相似文献
958.
HU Fang ZHANG Chun-hua ZHANG Song MING Xing CHEN Gang WEI Ying-jin WANG Chun-zhong . School of Materials Science Engineering Shenyang University of Technology Shenyang P. R. China . College of Physics State Key Laboratory of Superhard Materials Jilin University Changchun . College of Physical Science Technology Huanggang Normal University Huanggang 《高等学校化学研究》2011,(3):528-530
1 Introduction Low-dimensional nanostructures, such as nanorods, nanowires, and nanotubes, have received much attention for their superior optical, electrical, catalytic and magnetic properties. 相似文献
959.
Chuan Fu College of Architecture North China University of Technology Beijing China 《Acta Mechanica Sinica》2011,27(5):817-822
The sealed,tuned liquid column gas damper (TLCGD) with gas-spring effect extends the frequency range of application and efficiently increases the modal structural damping.Active tuned liquid column gas damper (ATLCGD) is developed for the vibration control of plane asymmetric buildings subjected to earthquake excitation,improving the performance of the passive control scheme.The active behaviour is obtained by adjusting the pressure at the end of the liquid column using a pressurised reservoir.The classical linear quadratic regulator (LQR) design is presented as a straightforward approach to optimal control.Numerical simulations indicate a significant vibration reduction of plane asymmetric buildings by active control within the strong motion of the dynamic response. 相似文献
960.
WANG Cui ZHANG Quan ZHANG XiaoFeng LIU Jing & LIU WeiPing College of Biological Environmental Engineering Zhejiang University of Technology Hangzhou China Key Laboratory of Environmental Remediation Ecosystem Health Ministry of Education College of Environmental Resource Sciences Zhejiang University Hangzhou China 《中国科学:化学》2010,(5)
Synthetic pyrethroids(SPs) ,a family of chiral insecticides consisting of multiple stereoismers,have been regarded as estrogenic endocrine-disrupting chemicals(EDCs) .In this study,we applied the yeast two-hybrid and molecular docking(MD) assay to assess the enantioselective estrogenic activities of three commonly used SPs,bifenthrin(cis-BF) ,permethrin(PM) and fenvalerate(Fen) .The β-galactosidase analyses indicated that all of the testing pyrethroids displayed significant(p<0.05) enantioselectivity.The re... 相似文献