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Yinfeng Yang Yan Li Yanqiu Pan Jinghui Wang Feng Lin Chao Wang Shuwei Zhang Ling Yang 《International journal of molecular sciences》2016,17(1)
As a chronic disorder, insomnia affects approximately 10% of the population at some time during their lives, and its treatment is often challenging. Since the antagonists of the H1 receptor, a protein prevalent in human central nervous system, have been proven as effective therapeutic agents for treating insomnia, the H1 receptor is quite possibly a promising target for developing potent anti-insomnia drugs. For the purpose of understanding the structural actors affecting the antagonism potency, presently a theoretical research of molecular interactions between 129 molecules and the H1 receptor is performed through three-dimensional quantitative structure-activity relationship (3D-QSAR) techniques. The ligand-based comparative molecular similarity indices analysis (CoMSIA) model (Q2 = 0.525, R2ncv = 0.891, R2pred = 0.807) has good quality for predicting the bioactivities of new chemicals. The cross-validated result suggests that the developed models have excellent internal and external predictability and consistency. The obtained contour maps were appraised for affinity trends for the investigated compounds, which provides significantly useful information in the rational drug design of novel anti-insomnia agents. Molecular docking was also performed to investigate the mode of interaction between the ligand and the active site of the receptor. Furthermore, as a supplementary tool to study the docking conformation of the antagonists in the H1 receptor binding pocket, molecular dynamics simulation was also applied, providing insights into the changes in the structure. All of the models and the derived information would, we hope, be of help for developing novel potent histamine H1 receptor antagonists, as well as exploring the H1-antihistamines interaction mechanism. 相似文献
989.
正1存在的问题我公司SCD1000熟料输送链斗机自投产以来,一直存在头轮齿块松动的问题。齿块松动会造成齿块与链条啮合不到位,加剧齿块和链条磨损,如不及时处理,可能会导致齿块断裂,链条跑偏甚至脱落等严重设备事故。故每次停机检修,均需安排人员对 相似文献
990.
Abstract In this paper, a novel detuning index is first proposed for indicating the proper timing required to correct the rotor time constant of indirect rotor flux oriented controlled single‐cage induction motor drives. This index can faithfully reflect the influence of rotor resistance changes as well as rotor flux changes. It also reduces greatly the number of rotor time constant estimations in practical applications. The theoretical basis of the index and the physical meaning are described in the paper in detail. Based on the proposed index, an on‐line rotor time constant estimator is also proposed to make corrections. Only existing available quantities of the closed loop controller are used for calculating the estimated rotor time constant accurately. Both simulation and experimental results verify the effectiveness of the proposed rotor flux orientation technique. It is seen that the proposed rotor flux orientation technique is suitable for practical applications. 相似文献