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排序方式: 共有2696条查询结果,搜索用时 15 毫秒
61.
Electrocatalysts: Guided Evolution of Bulk Metallic Glass Nanostructures: A Platform for Designing 3D Electrocatalytic Surfaces (Adv. Mater. 10/2016) 下载免费PDF全文
Gustavo Doubek Ryan C. Sekol Jinyang Li Won‐Hee Ryu Forrest S. Gittleson Siamak Nejati Eric Moy Candy Reid Marcelo Carmo Marcelo Linardi Punnathat Bordeenithikasem Emily Kinser Yanhui Liu Xiao Tong Chinedum O. Osuji Jan Schroers Sundeep Mukherjee André D. Taylor 《Advanced materials (Deerfield Beach, Fla.)》2016,28(10):1902-1902
62.
The effect of small dose of topiroxostat on serum uric acid in patients receiving hemodialysis 下载免费PDF全文
Yume Nagaoka Yoshiko Tanaka Hiroshi Yoshimoto Rie Suzuki Kakei Ryu Mio Ueda Minako Akiyama Miho Nagai Yoshitaka Miyaoka Eiichiro Kanda Shinnichi Iwai Michio Nagaoka Yoshihiko Kanno 《Hemodialysis international. International Symposium on Home Hemodialysis》2018,22(3):388-393
Introduction : Topiroxostat, a recently developed xanthine oxidase inhibitor, is expected to have fewer adverse effects than allopurinol because it has different mechanism of action from alloprinol. However, its dosage, usage and safety have not been established in patients with impaired renal function or those undergoing dialysis at the development since no studies was conducted in these patients. Methods : Cross over clinical trial using 3 months of allopurinol and topiroxostat on 27 maintain Japanese HD patients were carried out. The effects on oxidative stress status of both drugs were also evaluated by measuring oxidation reduction potential. Findings : Twenty‐five of twenty‐seven patients completed study. The mean serum uric acid levels in the topiroxostat‐treated arm was significantly lower than it in the allopurinol‐treated arm time‐dependently (P < 0.0001). Corrected oxidative stress ratio defined as biological antioxidant potential/diacron reactive oxygen metabolites was significantly increased in topiroxostat‐arm (*P = 0.0035), but not in allopurinol‐arm (P = 0.1429). No significant difference was seen in diacron reactive oxygen metabolites, biological antioxidant potential, static oxidation‐reduction potential, and capacity oxidation‐reduction potential between pre and post treatment of both drugs. Discussion : It is suggested that a low dose of topiroxostat decreased serum uric acid sufficiently to maintain it below 7.0 mg/dL in patients receiving hemodialysis. 相似文献
63.
Statistics is essential to design experiments and interpret experimental results. Inappropriate use of the statistical analysis, however, often leads to a wrong conclusion. This concept article revisits basic concepts of statistics and provides a brief guideline of applying the statistical analysis for scientific research from designing experiments to analyzing and presenting the data. 相似文献
64.
65.
S. S. Cho B. S. Chun C. H. Won B. S. Lee H. K. Kim B. J. Song M. Ryu 《Advanced Performance Materials》1996,3(1):29-42
The Al-12Si-5Fe-3Cu-1Mg(wt%) alloy was rapidly solidified by centrifugal atomization. The microstructural characteristics of rapidly solidified powder and the microstructure changes with heat treatment were investigated in terms and related to powder size. The microstructures of the powder consisted of dendritic -Al, eutectic phase, Cu-rich phase, and needle-like intermetallic compounds. These phases were much finer than that of ingot cast structure and the size decreased with increasing cooling rate. The X-ray diffraction of the atomized powders revealed the presence of non-equilibrium 3-(AlFeSi) intermetallic phase. This phase appeared to transform to an equilibrium -(AlFeSi) phase by heating at temperatures above 470°C. The extruded rod which was hot extruded at 360°C with an extrusion ratio of 40:1 also revealed the presence of the -(AIFeSi) intermetallic phase. Using DSC, the exothermic peak due to precipitation from the supersaturated -Al matrix was observed in the range of 200–250°C during continuous heating of atomized powder, and the size of the peaks increased with decreasing powder size. 相似文献
66.
J Iida AM Meijne JR Knutson LT Furcht JB McCarthy 《Canadian Metallurgical Quarterly》1996,7(3):155-162
Genes that encode enzymes that convert inactive "prodrugs" into anticancer metabolites may be therapeutically useful against brain tumors. Unlike other genes tested to date in brain tumor models, the Escherichia coli gpt gene is unique in that it not only sensitizes cells to the prodrug 6-thioxanthine (6TX) but also encodes resistance to a different regimen (mycophenolic acid, xanthine, and hypoxanthine), thus providing a means to select for gpt-positive cells. In the present study, rat C6 glioma cells were infected with a retrovirus vector that transduces this gene. A clonal line (C6GPT-7) was derived that exhibited significant 6TX susceptibility in vitro with an ID50 of 2.5 mumol/L, whereas 50% growth inhibition of parental C6 cells was not achieved at concentrations tested (up to 50 mumol/L). This line also exhibited significant sensitivity to 6-thioguanine (6TG), with an ID50 of 0.05 mumol/L, whereas 50% growth inhibition of parental C6 cells was achieved at 0.5 mumol/L. In a "bystander" assay, C6GPT-7 tumor cells efficiently transferred 6TX sensitivity to C6 cells at ratios as low as 1:9 (C6GPT-7:C6). This in vitro bystander effect was abrogated when C6GPT-7 and C6 cells were separated by a microporous membrane, suggesting that it was not mediated by highly diffusible metabolites. In vivo both 6TX and 6TG significantly inhibited the growth of subcutaneously transplanted C6GPT-7 cells but not that of C6 cells in athymic mice. In an intracerebral model, both 6TX and 6TG exhibited significant antiproliferative effects against tumors formed by C6GPT-7 cells. These findings provide a basis for exploring further gene therapy strategies based on in vivo transfer of the E coli gpt gene to provide chemosensitivity against 6TX and 6TG. 相似文献
67.
Dong-Pyoung Sheen Tae-geun Son Dae-Kwang Myung Cheolho Ryu Sang Hun Lee Kunwoo Lee Tae Jung Yeo 《Computer aided design》2010,42(8):720-730
A simplified geometric model with lower dimensionality, such as a mid-surface model, is often preferred over a detailed solid model for the analysis process, if the analysis results are not seriously impacted. In order to derive a mid-surface model from a thin-walled solid model, in this paper, we propose a novel approach called the solid deflation method. In this method, a solid model is assumed to be created by using air to inflate a shell that comprises the surface of the solid model. First, the model is simplified by the removal of any detailed features whose absence would not alter its overall shape. Next, the solid model itself can be converted into a degenerate solid model with zero thickness. Finally, a surface model is generated by splitting large faces paired in the thinned solid model, selecting one face per pair for creating a sheet model, and sewing the selected faces. Using this method, a more practical and usable mid-surface model can be very efficiently generated from a solid model because it can circumvent not only the tedious trimming and extension processes of the medial axis transformation method but also the time-consuming patch joining process of the mid-surface abstraction approach. 相似文献
68.
Jihoon Yeo Jejun Ryu Bong-Kee Lee Euihyeon Byeon Tai Hun Kwon Dong Sung Kim 《Microsystem Technologies》2010,16(8-9):1425-1430
Various types of polymer surfaces with a nanolens array, which has an entrant shape with a low aspect ratio, were fabricated and the wettability of the fabricated surfaces was evaluated in both theoretical and experimental ways. The nanolens array was replicated on three different polymer surfaces of polydimethylsiloxane (PDMS), cyclic olefin copolymer (COC), and polymethylmethacrylate (PMMA) by means of replica molding and hot embossing with a nanodimpled aluminum mold that was manufactured by a chemical oxidation process. From the theoretical and experimental evaluations of the wettability it was found that the measured contact angles were very similar with the theoretically estimated ones and also the hydrophilicity and hydrophobicity of the hydrophilic PMMA and hydrophobic PDMS, respectively, surfaces were reinforced by the nanolens array within the Wenzel wetting state. 相似文献
69.
Sang‐Hee Ko Park Min‐Ki Ryu Sung‐Min Yoon Shinhyuk Yang Chi‐Sun Hwang Jae‐Hong Jeon 《Journal of the Society for Information Display》2010,18(10):779-788
Abstract— The stability of oxide TFTs has been the main focus of this research and is probably the most crucial requirement for the successful application to flat‐panel displays. Although the high Fermi level of oxide semiconductors makes TFTs basically stable under electrical stress, the device reliability under diverse variations of electrical stress is affected by materials such as active semiconductors and gate insulators, processes for the formation of back/front channels and passivation layers, and device configurations among other things. How these factors affect the device reliability have been investigated and a review of the stability is presented. In addition, several categories of the light instability of oxide TFTs is presented and the origin is discussed. 相似文献
70.
Tae-Il Suh Eui-Jin Kim Bum-Jik Lee Jon-Ha Ryu Sung-Eun Lee 《International Journal of Control, Automation and Systems》2010,8(2):454-461
This article describes the performance comparison of several tracking filters from the viewpoint of gun fire control. It is common that filter performance can be represented by the RMSE of the current state. However, for the design of a gun fire control system, the performance of the tracking filter in terms of prediction is more important since the current state proceeds with a designed dynamic model to a certain future which is used for the final gun order. It is shown that the predicted results amplify the current state RMSE and can be a good measure. 相似文献