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排序方式: 共有238条查询结果,搜索用时 15 毫秒
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Abachi S Baringer P Bylsma BG DeBonte R Koltick D Loeffler FJ Low EH McIlwain RL Miller DH Ng CR Rangan LK Shibata EI Derrick M Gan KK Kooijman P Loos JS Musgrave B Price LE Repond J Sugano K Weiss JM Wood DE Blockus D Brabson B Brom J Jung C Ogren H Rust DR Akerlof C Chapman J Errede D Kesten P Meyer DI Nitz D Seidl AA Thun R Willutzky M Cork B 《Physical review letters》1986,57(16):1990-1993
3.
Julliane Diniz Yoneda Magaly Giro Albuquerque Ktia Zaccur Leal Peter R. Seidl Ralph A. Wheeler Scott E. Boesch Ricardo Bicca de Alencastro Maria Cecília B.V. de Souza Vitor F. Ferreira 《Journal of Molecular Structure》2006,778(1-3):97-103
Conformational analysis of nucleosides may have direct applications to the structure–activity relationship (SAR) studies and in the design of new drug candidates. Although conformational analysis may be accessed in many different ways, in this work it was performed using molecular dynamics (MD) simulation in order to study the dynamic behavior of a nucleoside derivative of 1,4-dihydro-4-oxoquinoline-3-carboxylic acid, synthesized by our group as a potential antiviral agent. The MD simulation was carried out during 10 ns in vacuum and in a box of water at two different temperatures (i.e., 300 and 600 K) using the AMBER force field. The in vacuum MD simulation results are in agreement with the crystallographic structure and with the DFT calculations of the nucleoside, revealing the anti conformer as the more stable one. The simulation in water, however, shows that both conformers may exist at 300 K, the temperature of the in vivo and in vitro assays, revealing that both the syn and anti conformers should be considered in a MD simulation study of the inhibitor–enzyme complex. Simulations are also in agreement with the NOE experiment, which shows that the anti conformer is the preferential one in DMSO-d6 solution at 298 K. 相似文献
4.
The development of a competitive solid-phase immunoassay for digoxin making use of the acridinium chemiluminescence system is described. Two different instrumental approaches are compared. One is based on a continuous flow system using a peristaltic flow injection analysis pump; the other uses a new sequential injection technique. In both systems a flow cell, consisting of transparent PTFE tubing packed with immobilized antibodies, acts as an immunoreactor. The entire assay, including both the immunoreaction and the chemiluminescence reaction, takes place in this immunoreactor cell. Compared with the flow injection technique, the sequential injection mode showed higher precision, ranging from 2.16 to 5.5% RSD depending on concentration. The total assay time, including regeneration, is less than 8 min with the sequential injection technique. The detection limit for both techniques is in the low femtomole range. 相似文献
5.
Feichtinger Gustav Hartl Richard F. Kort Peter M. Seidl Andrea Wrzaczek Stefan 《Journal of Optimization Theory and Applications》2022,194(3):878-895
Journal of Optimization Theory and Applications - This paper considers a capital accumulation game where the installation costs of investments are lowered by the firm’s own capital stock... 相似文献
6.
Beltrami I Bylsma BG DeBonte R Gan KK Koltick D Loeffler FJ Low EH McIlwain RL Miller DH Ng CR Ong PP Rangan LK Shibata EI Wilson RJ Derrick M Fernandez E Fries R Hyman L Kooijman P Loos JS Musgrave B Price LE Schlereth J Sugano K Weiss JM Wood DE Baranko G Baringer P Blockus D Brabson B Forden GE Gray SW Jung C Neal H Ogren H Rust DR Valdata-Nappi M Akerlof C Bonvicini G Chapman J Errede D Harnew N Kesten P Kooijman S Meyer DI Nitz D Rubin D Seidl AA Thun R Trinko T Willutzky W Cork B Keller L 《Physical review letters》1985,54(16):1775-1778
7.
R. Friary J. H. Schwerdt V. Seidl F. J. Villani 《Journal of heterocyclic chemistry》1990,27(2):189-193
Arylmethylimidazolines and (3-chlorophenyl)methyl-1,4,5,6-tetrahydropyrimidine amidated 2-chloro-3-pyridinecarbonyl chloride, and potassium t-butoxide cyclized the products to linearly fused, tricyclic imidazo-and pyrimido[1,2-g][1,6]naphthyridinones. Condensation of ethyl 2-chloro-3-pyridinecarboxylate with 2-(phenylmethyl)imidazoline in the presence of sodium methoxide directly formed the isomeric, angularly fused 8,9-dihydro-6-phenylimidazo[1,2-a ] [1,8]naphthyridin-5(7H-one. 相似文献
8.
M. Seidl M. E. Spina M. Brack 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1991,19(4):101-103
We report on semiclassical density variational calculations for spherical alkali metal clusters in the jellium model. We derive liquid-drop model expansions for total energy, ionisation potential and electron affinity and test the coefficients numerically for clusters with up toN=105 atoms. From the limitN→∞, we obtain excellent agreement with surface tensions and work functions evaluated for an infinite plane metal surface. 相似文献
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10.
To initiate the high-pressure polymerization of ethylene, oxygen is used together with organic peroxides in a number of tubular reactor processes. Since molecular oxygen is capable of promoting or inhibiting radical polymerization, depending on the reaction conditions chosen, controlled experiments were carried out to clarify these aspects of high pressure ethylene polymerization. In continuous polymerization tests carried out at 1700 bar and temperatures between 110 and 320°C, conversions were determined with tert-amyl perneodecanoate and di-tert-butyl peroxide initiation in the presence of various quantities of oxygen. Batch tests using a photo-initiator together with oxygen were also carried out. A comparison with polymerizations under conditions of careful elimination of oxygen shows no effect on the peroxide-initiated polymerization up to temperatures of 160 to 170°C. Although oxygen is an initiator at higher temperatures, the conversions obtained from the simultaneous addition of controlled quantities of oxygen and organic peroxides is lower than that obtained by adding together the conversions from the separate polymerizations. 相似文献