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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
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N Muto A Dota T Tanaka N Itoh M Okabe A Inada T Nakanishi K Tanaka 《Canadian Metallurgical Quarterly》1995,18(11):1576-1579
Hinokitiol, a constituent of the wood of Chamaecyparis taiwanensis, was found to induce differentiation of teratocarcinoma F9 cells. When examined by the agar-overlay method, in which expression of plasminogen activator as a differentiation marker protein was detected, this compound exhibited a dose- and time-dependent induction. Induction of differentiation by hinokitiol occurred irreversibly and required its addition for more than 12h. Among its structure-related compounds tested, tropolone and two colchicine-related compounds exerted potent activities comparable to that of hinokitiol. These findings indicate that free tropolone structure in the molecules plays an essential role in inducing differentiation of F9 cells. Hinokitiol showed a strong inhibitory effect of DNA synthesis in very early stages of culture, suggesting that this effect may be responsible for triggering differentiation of F9 cells. 相似文献
884.
J. Lee R. T. Haftka O. H. Griffin Jr. L. T. Watson M. D. Sensmeier 《Structural and Multidisciplinary Optimization》1994,8(2-3):93-100
The present study proposes a detection technique for delaminations in a laminated beam. The proposed technique optimizes the spatial distribution of harmonic excitation so as to magnify the difference in response between the delaminated and intact beam. The technique is evaluated by numerical simulation of two-layered aluminum beams. Effects of measurement and geometric noise are included in the analysis. A finite element model for a delaminated composite, based on a layer-wise laminated plate theory is used in conjunction with a step function to simulate delaminations 相似文献
885.
ADS Expert is an integrated system that (a) provides suggestions about suitable optimization algorithms for a particular structural optimization problem, (b) it offers explanations and guide lines, in the form of hypertext, that refer to the optimization strategy, optimizer and one dimensional search method, (c) it produces the required gradients for the objective function and the constraints using symbolic differentiation, (d) establishes a direct linking with ADS routines and (e) it monitors the evolution of the optimization process. The system can be used as an educational tool for structural optimization and as an efficient integrated system for small to medium size optimization problems for which the objective function and the constraints are given in the form of explicit functions of the design variables. The system is a Windows application and runs quite satisfactorily on PCs. 相似文献
886.
A Ikeda K Fujimoto I Yoshii S Matsumoto K Nishitani K Ikeda 《Canadian Metallurgical Quarterly》1993,68(4):410-421
Ever since 1974, the cadaver has been embalmed by the arterial embalming method, using pre-embalming fluid with blood clot disperser and cell conditioner for the removal of blood clots and drainage of blood, at the Department of Anatomy of the Kawasaki Medical School. According to this method, the cadavers are always very well fixed so that they can be used for not only anatomical dissection but also research for the vascular system by vasography, kinematics of the joint and other histologic examinations. In this report we have described our embalming procedure concretely and its application to research. 相似文献
887.
H. Haenel 《Molecular nutrition & food research》1993,37(3):299-299
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The geo-electrical measuring technique is frequently used for restoration purposes. However, this technique as developed in geology cannot be used without adaptations. The structure that is analysed has geometrical boundaries which influence the measurements and can lead to errors in the interpretation if they are not taken into account. This is illustrated by practical and theoretical tests. In an extensive test programme other aspects of the technique are also considered, such as the influence of electrode configuration and of moisture content. 相似文献