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171.
Several 2-heteroaryl-, 2-heteroarylcarbonylmethyl-, 2-arylcarbonylmethyl, and 2-arylethyl derivatives of S-dihydro(alkyloxy)benzyloxypyrimidines have been synthesized and the anti-HIV activities of these compounds were tested in C8166 cell and against RT enzyme. It was found that some of these compounds showed good activity against HIV-1 (EC 50 = 0.014–0.8 μM) with low toxicity (CC 50 value of 222–564 μM) and high selectivity (SI value of 278–37743). The structure-activity relationships (SAR) of these compounds have also been discussed. First two authors contributed equally to this work Correspondence: Yan-Ping He, Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming 650091, People’s Republic of China; Yong-Tang Zheng, Laboratory of Molecular Immunopharmacology, Key Laboratory of Animal Models and Human Disease Mechanisms, Chinese Academy of Sciences, Kunming Institute of Zoology, Kunming, Yunnan 650223, People’s Republic of China.  相似文献   
172.
As a famous traditional Chinese formula, Danshen Decoction has the potential to relieve the pain of pulmonary arterial hypertension patients, however, the functional components remain unknown. Herein, we reported a method to screen the functional components in Danshen Decoction targeting endothelin receptor A, an accepted target for the treatment of the disease. The receptor was functionalized on the macroporous silica gel through an epidermal growth factor receptor fusion tag and its covalent inhibitor. Using the affinity gel as the stationary phase, the bioactive compound was identified as salvianolic acid B by mass spectrometry. The binding kinetic parameter (dissociation rate constants kd) of salvianolic acid B with the receptor was determined via peak profiling. Using the specific ligands of the receptor as probes, the binding configuration prediction of salvianolic acid B with the receptor was performed by molecular dynamics simulation. Our results indicated that salvianolic acid B is a potential bioactive compound in Danshen Decoction targeting the receptor. This work showed that receptor chromatography in combination with molecular dynamics simulation is applicable to predicting the binding kinetics and configuration of a ligand to a receptor, providing crucial insight for the rational design of drugs that recognize functional proteins.  相似文献   
173.
In this article, we construct three new holomorphic vertex operator algebras of central charge 24 using the \({\mathbb{Z}_{2}}\)-orbifold construction associated to inner automorphisms. Their weight one subspaces have the Lie algebra structures D7,3A3,1G2,1, E7,3A5,1, and \({A_{8,3}A_{2,1}^2}\). In addition, we discuss the constructions of holomorphic vertex operator algebras with Lie algebras A5,6C2,3A1,2 and \({D_{6,5}A_{1,1}^2}\) from holomorphic vertex operator algebras with Lie algebras C5,3G2,2A1,1 and \({A_{4,5}^2}\), respectively.  相似文献   
174.
A facile approach was exploited for fast preparation of polymer-based monoliths in UV-transparent fused-silica capillaries via “one-pot” photo-initiated thiol-acrylate polymerization reaction of dipentaerythritolpenta-/hexaacrylate (DPEPA) and 1-octadecanethiol (ODT) in the presence of porogenic solvents (1-butanol and ethylene glycol). Due to relative insensitivity of oxygen inhibition in thiol-ene free-radical polymerization, the polymerization could be performed within 5 min. The effects of composition of prepolymerization solution on the morphology and permeability of poly(ODT-co-DPEPA) monoliths were investigated in detail by adjusting the content of monomer and binary porogen ratio. The physical properties of poly(ODT-co-DPEPA) monoliths were characterized by Fourier transform infrared spectroscopy (FT-IR), mercury intrusion porosimetry (MIP) and nitrogen adsorption/desorption measurement. The evaluation of chromatographic performance was carried out by capillary liquid chromatography (cLC). The results indicated that the poly(ODT-co-DPEPA) monolith was homogeneous and permeable, and also possessed a typical reversed-phase retention mechanism in cLC with high efficiency (∼75,000 N m−1) for separation of alkylbenzenes. Eventually, the further separation of tryptic digest of proteins by cLC tandem mass spectrometry (cLC-MS/MS) demonstrated its potential in the analysis of biological samples.  相似文献   
175.
In the present paper, we generalize the linear canonical transform (LCT) to quaternion‐valued signals, known as the quaternionic LCT (QLCT). Using the properties of the LCT, we establish an uncertainty principle for the two‐sided QLCT. This uncertainty principle prescribes a lower bound on the product of the effective widths of quaternion‐valued signals in the spatial and frequency domains. It is shown that only a Gaussian quaternionic signal minimizes the uncertainty. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
176.
张克声  朱明  唐文勇  欧卫华  蒋学勤 《物理学报》2016,65(13):134302-134302
振动弛豫时间是可激发气体分子内外自由度能量转移速率的宏观体现,它决定了声吸收谱峰值点对应的弛豫频率.本文给出了等温、绝热定压和绝热定容三种不同热力学过程下振动弛豫时间的相互关系;基于Petculescu和Lueptow[2005 Phys.Rev.Lett.94 238301]的弛豫过程合成算法,推导了单一压强下两频点声测量值的弛豫时间重建算法.该算法可应用于等温、绝热定压、绝热定容弛豫时间和弛豫频率的重建测量,并避免了弛豫时间传统声测量方法需要不断改变气体腔体压强的问题.仿真结果表明,对于室温下CO_2,CH_4,Cl_2,N_2和O_2组成的多种气体,重建的弛豫时间和弛豫频率与实验数据相符.  相似文献   
177.
In this study, we compared the wetting and electrowetting properties of a planar parylene (poly(p-xylylene)) film to those of a nanostructured parylene film. To generate the nanostructured film, we used an aligned array of multiwalled carbon nanotubes as a template; a thin coating of parylene was deposited on the nanotube template to generate a parylene film with a nanoscale roughness structure. Static contact angle measurements indicated a very significant increase in the water contact angle from approximately 73 degrees for planar parylene to approximately 110 degrees for the nanotemplated parylene. In addition, we performed electrowetting experiments to dynamically tune the contact angle by application of electric potential. Interestingly, the flat parylene film showed contact angle saturation at an applied voltage of approximately 40 V, while the nanotemplated parylene film did not experience saturation in the contact angle response even for voltages up to 80 V. These results show that engineering a nanoscale roughness structure to a polymer film results in significant changes to the wetting and electrowetting properties of the polymer.  相似文献   
178.
毛细管电泳涂层柱技术的进展   总被引:8,自引:0,他引:8  
康经武  陆豪杰  欧庆瑜 《色谱》1998,16(1):26-29
毛细管电泳涂层柱是解决蛋白质在毛细管壁吸附的最有效的方法。较为系统地综述了毛细管电泳涂层柱的几种制作方法,指出了毛细管电泳涂层柱(包括毛细管电色谱柱)的发展趋势,39篇。  相似文献   
179.
毛细管离子电泳   总被引:7,自引:1,他引:6  
宋立国  欧庆瑜  俞惟乐 《色谱》1996,14(2):98-101
Capillary ion electrophoresis (CIE) was reviewed with 72 references. It is firstly compared with ion chromatography(IC). Then detection method, separation and analysis methods of anions and cations were guidelined. Determination of ions in various samples was also reviewed.  相似文献   
180.
从1970年以来,不少学者对场效应敏感器件(简称ISFET)做了研究[1-4],本文作者利用二-(二异辛基苯基磷酸)钙为电活性物质研制成Ca2+-ISFET,并测定了器件的各项性能参数。  相似文献   
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