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排序方式: 共有1421条查询结果,搜索用时 62 毫秒
21.
BACKGROUND: We determined the types and distribution of glycosaminoglycans (GAGs) and collagens, in anterior capsular opacification after endocapsular phacoemulsification and aspiration (ECPEA) and intraocular lens implantation. METHODS: Opacified anterior capsules were removed from human eyes after ECPEA. Immunohistochemical staining was performed to determine GAGs with monoclonal antibodies to chondroitin, chondroitin-4-sulfate (C4S), chondroitin-6-sulfate (C6S), dermatan sulfate (DS), and keratan sulfate (KS); collagens with monoclonal antibodies to types I, II, and III collagens; and cellular characteristics with monoclonal antibodies to vimentin, desmin, alpha-smooth muscle actin, and cytokeratin. Decorin mRNA and type I collagen mRNA were detected by in situ hybridization. RESULTS: In the capsules, the C6S, DS, KS, and types I and III collagens were similar to the chemical components found at the adhesion site of the anterior and posterior capsules after extracapsular cataract extraction, and cellular components contained vimentin, desmin, alpha-smooth muscle actin, cytokeratin, decorin mRNA, and type I collagen mRNA. CONCLUSIONS: The GAGs and collagens in opacified anterior capsule after ECPEA were similar to those found during wound healing, although KS is present in normal anterior segment tissue during development and only in the cornea postnatally. These chemical components may be produced by myofibroblast-like cells presumably transformed from lens epithelial cells. 相似文献
22.
Various liquid polybutadiene derivatives were examined as modifiers to improve the brittleness of phenolic resins. Amidated polybutadienes obtained from a maleinated polybutadiene and ammonia had the highest curing tendency when they were reacted with resole under mild conditions. The cured resins were homogeneous and the brittleness of the phenolic resins was remarkably improved. Crosslinking efficiency was closely related to the succinamic acid group of the amidated polybutadiene. Thermal behavior of the succinamic acid group was also related to the effects of curing temperature and curing time on crosslinking. From these observations, cross-condensation between the succinamic acid group of an amidated polybutadiene and resole seemed to have occurred to a great extent than the self-condensation of resole itself and oxidative crosslinking of the amidated polybutadiene. 相似文献
23.
In this article, a new control scheme named repetitive control is proposed for a class of nonlinear systems described by x(t) = Ax(t) + Bu(t) + n(x(t)) and y(t) = Cx(t), in which the controlled variables follow periodic reference commands. The stability condition is derived by applying the passivity theorem. We show how to apply the repetitive control scheme to the trajectory control of a manipulator. A simple repetitive control scheme is developed for the trajectory control of a manipulator by using nonlinear compensation and feedbacks of position and velocity signals. Experimental results for a three link manipulator verify that the proposed repetitive control reduces the tracking error to a very low level. 相似文献
24.
A reduced order model predictive control (MPC) is discussed for constrained discrete‐time linear systems. By employing a decomposition method for finite‐horizon linear systems, an MPC law is obtained from a reduced order optimization problem. The decomposition enables us to construct pairs of initial state and control sequence which have large influence on system responses, and it also characterizes the standard LQ control. The MPC law is obtained based on a combination of the LQ control and dominant input sequences over the prediction horizon. The proposed MPC method is illustrated with numerical examples. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
25.
Taxonomy for protective ability of rust layer using its composition formed on weathering steel bridge 总被引:2,自引:0,他引:2
For a quantitative evaluation of the protectiveness of a rust layer formed on a weathering steel bridge, the relationship between the corrosion rate of the bridge and the composition of the rust layers formed on the girders was first investigated. These corrosion rates were clearly classified by the protective ability index (PAI) of α/γ∗ and (β + s)/γ∗, where α, γ∗, β and s are the mass ratio of crystalline α-FeOOH, the total of γ-FeOOH, β-FeOOH and the spinel-type iron oxide (mainly Fe3O4), β-FeOOH and spinel-type iron oxide, analyzed by XRD, respectively. The inequality of the former index α/γ∗ > 1 expressed the protectiveness criterion of the rust layer, while that of the latter index, (β + s)/γ∗< 0.5 or > 0.5, classified the corrosion rate of the non-protective rust layer. The PAI is useful for a quantitative evaluation of the protectiveness of a rust layer formed on a weathering steel bridge and is an important item for the corrosion assessment of the bridge. 相似文献
26.
Dr. Daisuke Okuno Dr. Noriho Sakamoto Dr. Mohammed S. O. Tagod Yoshiko Akiyama Dr. Sakiko Moriyama Dr. Takuto Miyamura Dr. Atsuko Hara Dr. Takashi Kido Dr. Hiroshi Ishimoto Prof. Yuji Ishimatsu Prof. Takashi Tanaka Prof. Jun Ishihara Prof. Kohsuke Takeda Prof. Yoshimasa Tanaka Prof. Hiroshi Mukae 《ChemMedChem》2021,16(16):2515-2523
Heat shock protein 47 (HSP47), a collagen-specific molecular chaperone, is causally related to fibrotic diseases, including idiopathic pulmonary fibrosis. The identification of Compounds that interfere with the HSP47-collagen interaction is essential for the development of relevant therapeutics. Herein, we prepared human HSP47 as a soluble fusion protein expressed in E. coli and established an assay system for HSP47 inhibitor screening. We screened a natural and synthetic Compound library established at Nagasaki University. Among 1023 Compounds, 13 exhibited inhibitory activity against human HSP47, of which three inhibited its function in a dose-dependent manner. Epigallocatechin-3-O-gallate, one of these three Compounds, is a typical polyphenol Compound derived from tea leaves. Structurally related Compounds were synthesized and examined for their activity, revealing a hydroxyl group at A-ring position 5 as important for its activity. The present findings provide valuable insight for the development of natural product-derived therapeutics for fibrotic diseases, including idiopathic pulmonary fibrosis. 相似文献
27.
Hydrothermal reactions of fumed silica with lime at 80°C were studied at starting Ca/Si of 0.8–2.0 and water/solid ratio of 20 by weight under periods of reaction time from 10 to 100 days.In the early ages of reaction, CSH having weak and diffuse basal reflections between 10–15Å was formed. On prolonging the reaction, CSH from the starting Ca/Si of 1.2–1.5 crystallised to jennite, and that from the starting Ca/Si of 0.9 to 14Å tobermorite.Lattice parameters were determined on the well crystalline jennite obtained by the reaction for 100 days at the starting Ca/Si of 1.4; i.e. ao 10.59, bo 7.21, co 10.82Å, α 99.60°, β 97.78°, γ 109.85°. Its crystals were lath-like elongated parallel to b with (001) cleavage.It was confirmed that the synthetic jennite was converted to meta-jennite by losing a part of its water on heating in air at 90°C. At higher temperatures it became poorly crystalline, and then crystallised to β-CaSiO3 and β-Ca2SiO4 at 800°C. 相似文献
28.
Gas absorption into laminar falling films of power-law liquids was studied theoretically and experimentally. The convective-diffusion equation was solved by the method of separation of variables and the analytical solution for the average Sherwood number was obtained as a function of the Graetz number and the power-law index of the liquid. Experiments were carried out on the absorption of pure carbon dioxide, hydrogen and helium into aqueous kaolin slurries by using a long wetted-wall column and the average absorption rates were measured as a function of the mass flow rate of the liquid. The experimental results were in good agreement with the theoretical predictions. 相似文献
29.
Kenton O’Hara Gerardo Gonzalez Graeme Penney Abigail Sellen Robert Corish Helena Mentis Andreas Varnavas Antonio Criminisi Mark Rouncefield Neville Dastur Tom Carrell 《Computer Supported Cooperative Work (CSCW)》2014,23(3):299-337
While surgical practices are increasingly reliant on a range of digital imaging technologies, the ability for clinicians to interact and manipulate these digital representations in the operating theatre using traditional touch based interaction devices is constrained by the need to maintain sterility. To overcome these concerns with sterility, a number of researchers are have been developing ways of enabling interaction in the operating theatre using touchless interaction techniques such as gesture and voice to allow clinicians control of the systems. While there have been important technical strides in the area, there has been little in the way of understanding the use of these touchless systems in practice. With this in mind we present a touchless system developed for use during vascular surgery. We deployed the system in the endovascular suite of a large hospital for use in the context of real procedures. We present findings from a study of the system in use focusing on how, with touchless interaction, the visual resources were embedded and made meaningful in the collaborative practices of surgery. In particular we discuss the importance of direct and dynamic control of the images by the clinicians in the context of talk and in the context of other artefact use as well as the work performed by members of the clinical team to make themselves sensable by the system. We discuss the broader implications of these findings for how we think about the design, evaluation and use of these systems. 相似文献
30.
Yoshiro Funakoshi Masaki Yamamoto Yoshihiko Matsumura Hiromu Komeda 《Powder Technology》1980,27(1):13-21
Necessary conditions were studied for the optimum operation of agglomeration granulation. The mechanisms that would realize these conditions were investigated by several experiments.On the basis of the results obtained, a novel granulating system involving a surface wetness control mechanism has been developed.The present paper describes the mixing and dispersing characteristics of the coating vessel, the detection method for wetness control, the particular spraying units, and the operating conditions thereof, together with the characteristics of this newly developed powder coating granulation system.This system has been shown to provide an easy and reproducible granulating technique even when products below 1 mm in size are required. 相似文献