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931.
提出并应用改进的分形方法对硫氧还蛋白还原酶(TrxR)结构进行研究。建立了适用于TrxR的分形及数据处理方法。发现正常的TrxR的结构分维值约为1.33,氧化后结构分维值增大。提出了蛋白质结构分维值是表征蛋白质分子状态的重要特征之一的观点,并结合TrxR验证了该观点。提出了药物分子分维值应与靶酶的结构分维值相契合的观点,并结合以TrxR为靶点的药物研发实验验证了该观点。 相似文献
932.
利用原子分子反应静力学的有关原理,推导出了CN分子的合理离解极限.采用密度泛函理论的B3LYP方法和二次组态相互作用的QCISD和QCISD(T)等理论方法,在D95(d),6-311G*和6-311 G*基组下,对CN分子基态的平衡结构、离解能和谐振频率进行了优化计算,利用QCISD/6-311 G*对CN分子的基态进行了单点能量扫描,并将扫描结果用正规方程组拟合Murrell-Sorbie势能函数.由拟合得到的势能函数计算与X2∑ 态相应的光谱常数(Be、eα、ωe和ωeχe),其结果与实验符合得较好. 相似文献
933.
934.
A method of constructing restriction map by optical mapping and single molecule fluorescent microscopy is described. DNA molecules were aligned and adsorbed on a glass coverslip surface by a modified “molecular combing” technique, and then the surface-immobilized DNAs were cleaved in situ with a restriction endonuclease. Individual DNA molecules digested by the endonuclease EcoRⅠ were observable with fluorescent microscopy. Using optical mapping, a physical map of a rice bacterial artificial chromosome clone was constructed. This method will facilitate genomic mapping and tracing the dynamic process in real time at a single molecule level with fluorescence microscopy. 相似文献
935.
水溶性杯芳烃在分析化学中的应用 总被引:3,自引:0,他引:3
综述了水溶性杯芳烃在分析化学中的研究进展,主要阐述了水溶性杯芳烃在光度法、电化学、色谱分离、毛细管电泳及分子识别等方面的应用。 相似文献
936.
Self-aggregation of vapor-liquid phase transition 总被引:5,自引:0,他引:5
The concept of the molecular free path is introduced to derive a criterion distinguishing active molecules from inactive molecules in liquid phase. Based on molecular self-aggregation theory a concept of the critical aggregation concentration (CAC) of active molecules is proposed to describe the physical configuration before the formation of the nuclei in the process of vapor-liquid phase transition. All active molecules exist in the form of the monomer when the concentration of active molecules is lower than CAC, while the active molecules will generate aggregation once the concentration of the active molecules reaches CAC. However, these aggregates with the aggregation number N smaller than 5 can steadily exist in bulk phase. The other excess active molecules can only produce infinite aggregation and form a critical nucleus of vapor-liquid phase transition. Without outer perturbation the state point of CAC corresponds to the critical superheated or supercooled state in the process of vapor-liquid phase transition. With the aggregate property, the interfacial tension between the bulk phase and the tiny new phase is predicted and a correction is made for the classical nucleation rate in a quite good agreement with experimental results. 相似文献
937.
Ya-Qin?Yu Can-Zhong?LuEmail author Xiang?He Shu-Mei?Chen Quan-Zheng?Zhang Li-Jun?Chen Wen-Bin?Yang 《Journal of chemical crystallography》2004,34(12):905-909
Single crystals of a symmetrically substituted molecule, [Zn(C3N6H6)(H2O)0.5Cl2] (C3N6H6)(H2O)(1), have been obtained. The crystal structure of 1 shows the existence of novel layered type supramolecular structure constructed by dumbbell-shape coordinated Zn moleculeand one 2,4,6-triamine-s-triazine ligand. Crystallographic data for 1: monoclinic system, space group: C2/c, a = 12.2532(9), b = 13.8606(10), c = 18.3603(13) Å, = 99.7860(10), V = 3072.9(4) Å3 and Z = 8, Dc = 1.758 Mg/m3, R1 = 0.0518. The fluorescent property of 1 has also been studied. The luminescent property of 1 attributable to both ligand * transitions and electronic transfer of ZnII O transitions. 相似文献
938.
Michael?SchmittelEmail author Guido?Morbach Wolfdieter?A.?Schenk Michael?Hagel 《Journal of chemical crystallography》2005,35(5):373-379
The crystal structure of the new enediyne 3 was determined by X-ray diffraction. 3 crystallizes in the orthorhombic space group Pbca (No. 61) with a = 12.7148(9) Å, b = 7.4872(8) Å, c = 38.890(4) Å, = = = 90 and Z = 8. The three-dimensional structure is characterized by an 8-membered cyclic array linking four molecules of 3 by hydrogen bonding between phenolic and methoxy groups. Furthermore, stabilization by –-stacking and CH s interactions is present. The important cd distance (between the two terminal acetylene carbons of the enediyne) which is relevant for the Bergman cyclization, was determined to 401 pm, being in good agreement with the high cyclization barrier ( G = 147.9 kJ mol–1 at 220C) that was determined by differential scanning calorimetry (DSC). 相似文献
939.
Reexamination of our study of [Rh2(HNOCCH3)4(2H2O)] 3H2O (Ahsan, M.Q.; Bernal, I.; Bear, J.L. Inorg. Chem.
1986, 26 260) showed it to be interesting not just because the dirhodium molecule is an antineoplastic but because it contains a hexameric cluster of waters trapped in Rh–Rh lattice cavities. It may well provide an interesting model for the smallest piece of ice (Nauta, K.; Miller, R.E. Science
2000, 287, 293). 相似文献
940.
目的:研究CD305分子在类风湿关节炎滑膜中的表达。方法:通过免疫组织化学染色方法分别检测CD305分子在类风湿关节炎(Rheumatoid arthritis,RA)、骨性关节炎(Osteoarthritis,OA)和正常创伤患者滑膜中的分布规律。结果:在RA组,CD305分子在所有患者滑膜组织中均有表达。在OA组,CD305分子在部分患者滑膜组织中表达。而在正常患者中,CD305分子在大部分滑膜组织中不表达,仅在部分样本边缘处有少量表达。结论:CD305分子在RA患者滑膜组织中表达高于正常创伤患者,且主要在里衬层(lining layer)滑膜成纤维细胞(fibroblast-like synoviocytes, FLS) 上高表达。 相似文献