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71.
基于分子对接和实验验证分析金银花不同溶剂提取物及主要成分抗RNA病毒蛋白酶的活性。利用TCMSP(traditional Chinese medicine systems pharmacology)构建金银花小分子配体库,采用药物分子设计模拟SYBYL 2.1.1软件分析金银花与HIV-1蛋白酶和Cathepsin L蛋白酶结合情况。通过荧光法验证金银花不同溶剂提取物(水提物、30%醇提物、60%醇提物和85%醇提物)抗HIV-1和Cathepsin L蛋白酶的活性。收集金银花22个化学成分,其中21个活性成分与HIV-1蛋白酶有较好的结合,金银花抗HIV-1蛋白酶活性强于Cathepsin L蛋白酶。金银花水提物、30%醇提物、60%醇提物和85%醇提物具有抗HIV-1的活性,IC50分别为0.14、0.015、0.05、0.121 mg/mL,其中30%醇提物具有较好的抗HIV-1的活性。金银花不同溶剂提取物未发现有强烈抑制组织蛋白酶的活性,实验结果和计算机筛选结果具有一致性。初步明确金银花抗HIV-1蛋白酶和Cathepsin L蛋白酶活性,为抗病毒药物的开... 相似文献
72.
研究了用于空间飞行器对接机构的差动式机电缓冲阻尼系统的动力学。提出了一种关于此类6自由度的串、并联复合系统的动力学分析方法。应用Lagrange分析技术推导出了系统动力学方程,给出了相应的系统约束方程,并对系统中多部位的库仑摩擦阻尼进行了处理和实例计算分析。结论表明该方法可进行差动式机电缓冲阻尼系统的动力学分析、系统刚度和阻尼特性分析以及系统功能校核分析。 相似文献
73.
Space electromagnetic docking technology,free of propellant and plume contamination,offers continuous,reversible and synchronous controllability,which is widely applied in the future routine on-orbit servicing missions.Due to the inherent nonlinearities,couplings and uncertainties of an electromagnetic force model,the dynamics and control problems of them are difficult.A new modeling approach for relative motion dynamics with intersatellite force is proposed.To resolve these control problems better,a novel nonlinear control method for soft space electromagnetic docking is proposed,which combines merits of artificial potential function method,Lyapunov theory and extended state observer.In addition,the angular momentum management problem of space electromagnetic docking and approaches of handling it by exploiting the Earth’s magnetic torque are investigated.Finally,nonlinear simulation results demonstrate the feasibility of the dynamic model and the novel nonlinear control method. 相似文献
74.
Polyoxometalate (POM) has promising antiviral activities. It shows broad-spectrum inhibiting ability, high efficiency, and low tox-icity. Experimental assays show that titanium containing polyoxotungstates have anti-influenza-virus activity. In this paper, the bind-ing mechanisms of five isomers of di-Ti-substituted polyoxotungstate, [α-1,2-PTi2W10O40]7– (α-1,2), [α-1,6-PTi2W10O40]7– (α-1,6), [α-1,5-PTi2W10O40]7– (α-1,5), [α-1,4-PTi2W10O40]7– (α-1,4) and [α-1,11-PTi2W10O40]7– (α-1,11), to five subtypes of influenza virus A neuraminidase (FluV-A NA) were investigated in the context of aqueous solution by using molecular docking and molecular dynamics studies. The results show that the isomer α-1,2 is superior to other isomers as a potential inhibitor to neuraminidase. The positively charged arginine residues around the active site of NA could be induced by negatively charged POM to adapt themselves and could form salt bridge interactions and hydrogen bond interactions with POM. The binding free energies of POM/NA complexes range from –5.36 to –8.31 kcal mol–1. The electrostatic interactions are found to be the driving force during the binding process of POM to NA. The conformational analysis shows that POM tends to bind primarily with N1 and N8 at the edge of the active pocket, which causes the conformational change of the pincers structure comprising residue 347 and loop 150. Whereas, the active pockets of N2, N9 and N4 are found to be more spacious, which allows POM to enter into the active pockets directly and anchor there firmly. This study shows that negatively charged ligand as POM could induce the reorganization of the active site of NA and highlights POM as a promising inhibitor to NA despite the ever increasing mutants of NA. 相似文献
75.
根据国家教育部《现代职业教育体系建设规划》要求,通过对建筑施工技能型人才内涵的理解,借鉴国外高等职业教育思想和培养模式,结合现代社会企业对建筑施工高端技能型人才知识结构、能力素质的需求,采取校企对接、专业与产业对接、课程内容与职业标准对接、职业资质与技能对接等方式,构建建筑施工高端技能型人才培养的新模式. 相似文献
76.
研究了一种应用于水下自重构机器人的新型水下湿式机电对接技术.采用多卡爪机械锁紧机构和充油密封方式,实现了水下可靠的机械与电气连接;利用机器人逆运动学方法实现关节的协调控制,进行对接过程末端模块的轨迹规划;利用对光电引导传感器组信号的优化来辅助水下对接;成功研制了该水下连接装置和基于该装置的水下自重构机器人样机.通过在样机上的实际应用,验证了该技术的有效性. 相似文献
77.
以SQS抑制剂CP 320473为先导物, 在60%结构相似性的基础上, 先通过AutoDock Vina软件进行分子对接, 再选取结合能量最低的新化合物进行分
子对接研究. 结果表明: zinc_8442249比先导化合物CP 320473的抑制效果更好; SQS活性位点的Lys52通过与氢键与抑制剂结合, 在抑制过程中具有重要作用. 相似文献
子对接研究. 结果表明: zinc_8442249比先导化合物CP 320473的抑制效果更好; SQS活性位点的Lys52通过与氢键与抑制剂结合, 在抑制过程中具有重要作用. 相似文献
78.
科学发展观在关于发展目的问题上,主张以生态良好为根本手段来实现人的全面发展;在人与自然之间关系问题上,坚持以践行生态正义为促进自然生态良好的根本动力;在人与人、社会之间关系问题上,强调以实现生态公平为推进社会生态良好的根本准则。可见,它即坚持以人为本,又倡导生态伦理,因而是一种实现了以人为本与生态伦理完美对接的科学理论。 相似文献
79.
Regulatory mechanisms of mitogen-activated kinase signaling 总被引:5,自引:1,他引:4
MAP kinases (MAPKs) are evolutionarily conserved regulators that mediate signal transduction and play essential roles in various
physiological processes. There are three main families of MAPKs in mammals, whose functions are regulated by activators, inactivators,
substrates and scaffolds, which together form delicate signaling cascades in response to different extracellular or intracellular
stimulation. MAPK signaling is tightly regulated so that optimal biological activities are achieved and health is maintained.
However, how the specificity of the signaling flow along each cascade is achieved is still relatively unclear. In this review,
we summarize recent advances in understanding the regulation of MAPK cascades and the roles of MAP kinases and their regulators
in development and in immune responses.
Received 11 January 2007; received after revision 31 May 2007; accepted 5 July 2007 相似文献
80.