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51.
R. Nageswara Rao R. Mastan Vali Bondigalla Ramachandra Pawan K. Maurya 《Biomedical chromatography : BMC》2011,25(11):1201-1207
The use of blood spot collection cards is a simple way to obtain specimens for therapeutic drug monitoring, assessing adherence to medications and preventing toxicity in a clinical setting. A high‐throughput liquid chromatography–electrospray ionization mass spectrometric (LC‐ESI‐MS) method for determination of rifaximin on dried blood spots (DBS) was developed and validated. It involves solvent extraction of a punch of DBS followed by reversed‐phase LC on a monolithic column consisting of a silica rod with bimodal pore structure and detection by ESI‐MS. Rifampicin was used as an internal standard (IS). The run time was within 5.0 min with a very low back‐pressure at a flow rate of 0.5 mL/min. The assay was linear from 0.1 to 10 ng/mL. The mean recovery was 98.42%. The developed method is very simple, rapid and useful for clinical applications. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
52.
In a model experiment wave packets (forerunners) have been detected for the first time in the flow regions preceding the fronts of streamwise structures in a swept wing boundary layer. The characteristics of the wave packets and the generating streamwise structures and the dynamics of their downstream development are investigated. It is shown that the forerunners can transform into turbulent spots thus leading to laminar-turbulent transition. Certain components of the forerunners are compared with a periodic instability wave. 相似文献
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Polycomb Polycomb repressive complex 2 (PRC2) plays a key role in silencing epigenetic gene through trimethylation of lysine 27 on histone 3 (H3K27). Dysregulations of PRC2 caused by overexpression and mutations of the core subunits of PRC2 have been implicated in many cancers. The core subunits EZH1/2 are histone-lysine N-methyltransferases that function as the enzymatic component of PRC2. While the core subunit EED is a scaffolding protein to support EZH1/2 and binds JARID2K116me3/H3K27me3 to enhance the enzymatic activity of PRC2 through allosteric activation. Recently, several small molecules that compete with JARI2K116me3 and H3K27me3 have been reported. These molecules selectively bind to the JARID2K116me3/H3K27me3-binding pocket of EED, thereby preventing the allosteric regulation of PRC2. These first-in-class PRC2 inhibitors show robust suppression in DLBCL cell lines, demonstrating anticancer drugs that target the EED subunit of PRC2 are viable. In this study, we used the recently developed MM/GBSA_IE and the alanine scanning method to analyze the hot spots in EED/inhibitor interactions. The analysis of these hot and warm spots helps us to understand the fundamental differences between inhibitors. Our results give a quantitative explanation on why the binding affinities of EED/A-395 interactions are stronger than that of EED/EED226 while their binding modes are similar and provide valuable insights for rational design of novel EED inhibitors. 相似文献
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正Cloud computing is a novel computing paradigm that utilizes remote cloud resources to achieve a high-performance computation.Cloud provides infrastructure,platform and software as different on-demand services.China has made remarkable progress in cloudbased products and operating system technology.The government,enterprises and research institutions are all active in the development of cloud computing-related projects.Despite the progress,many important problems 相似文献
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通过使用三张编码全息片和三种滤光片,用白光将彩色正片的红、绿、兰三色信息记录在一张或两张全息片上。用单色激光同时再现出记录的三种颜色信息的光强分布,并将它们记录在同一张全息片上作成彩色全息图。本方法的显著优点是消除了影响彩色全息图质量的激光斑纹及提高了彩色全息图制作中的光功率利用率。 相似文献
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近邻型风景旅游集镇规划的若干问题剖析 总被引:3,自引:0,他引:3
建设风景区旅游集镇既可以保护风景区的旅游资源,又可以促进集镇发展.根据风景区与旅游集镇的空间关系,对旅游集镇进行了类型上的划分.并以近邻型旅游集镇为研究对象,提出了编制近邻型旅游集镇规划所需解决的人口规模、功能布局、集镇特色和规划弹性4个关键问题;最后以西天目山风景区旅游集镇(白鹤)总体规划为例,阐述了解决上述问题的方法和手段. 相似文献
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Artem B. Mamonov Mohammad Moghadasi Hanieh Mirzaei Shahrooz Zarbafian Laurie E. Grove Tanggis Bohnuud Pirooz Vakili Ioannis Ch. Paschalidis Sandor Vajda Dima Kozakov 《Journal of computational chemistry》2016,37(11):961-970
The fast Fourier transform (FFT) sampling algorithm has been used with success in application to protein‐protein docking and for protein mapping, the latter docking a variety of small organic molecules for the identification of binding hot spots on the target protein. Here we explore the local rather than global usage of the FFT sampling approach in docking applications. If the global FFT based search yields a near‐native cluster of docked structures for a protein complex, then focused resampling of the cluster generally leads to a substantial increase in the number of conformations close to the native structure. In protein mapping, focused resampling of the selected hot spot regions generally reveals further hot spots that, while not as strong as the primary hot spots, also contribute to ligand binding. The detection of additional ligand binding regions is shown by the improved overlap between hot spots and bound ligands. © 2016 Wiley Periodicals, Inc. 相似文献
60.
The experimental observation of a two-dimensional self-organized square lattice pattern in a planar surface barrier discharge is reported. The discharge was operated near atmospheric pressure in helium gas. The transition from irregular plasma spot pattern to a square lattice pattern is achieved by reducing the discharge driving frequency. On increasing the driving frequency the regular lattice pattern is destroyed and again transforms to an irregular plasma spot pattern. Dielectric degradation and powder formation is also observed after discharge process. Spatio-temporal behavior of observed plasma pattern is presented. 相似文献