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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
E Legius H Cuppens H Dierick K Van Zandt R Dom JP Fryns G Evers-Kiebooms M Decruyenaere K Demyttenaere P Marynen 《Canadian Metallurgical Quarterly》1994,2(1):44-50
Pantoprazole is a specific inhibitor of the H+/K(+)-ATPase of the gastric parietal cell. The dose-dependency of a range of pantoprazole pharmacokinetic characteristics was studied. Twelve healthy male subjects were given 10, 20, 40 and 80 mg pantoprazole intravenously according to a randomized, single blind, 4-period change-over scheme. The area under the concentration vs time curve (AUC) and the maximum serum concentration (Cmax) showed a linear increase in line with the dose. Apparent volume of distribution (Vd area), clearance (Cl) and terminal half-life (t1/2) were independent of the dose. The dose-independent elimination of pantoprazole was attributed to the lack of interaction of the drug with cytochrome P450. In clinical practice, a good predictable response, as well as a low potential for interaction with other drugs might be expected. 相似文献
992.
This paper highlights the role of the faculty member in recruiting students currently enrolled in B.S. programs in engineering and the sciences into full-time pursuit of a graduate-level engineering degree. The faculty member is demonstrated to be in a unique position to influence such students, providing strong counterforces to a confluence of attitudes and pressures experienced during the B.S. experience which effectively create a barrier to full-time engineering graduate study. We analyze this barrier via the method of force field analysis, and demonstrate that effective recruitment into full-time graduate study must be based on a four-fold strategy of education, expectations, improved B.S. experience and better control of the B.S. environment. Approaches to implement these strategies are discussed. 相似文献
993.
The article deals with the problem of oscillations of laminated plates with large deflection. It analyzes the fields of application of the refined theory of shear for its solution.Translated from Problemy Prochnosti, No. 8, pp. 47–52, August, 1993. 相似文献
994.
In a review of 328 cases the combination of laparoscopic cholecystectomy with specific use of endoscopic retrograde cholangiography (pre- and postoperatively) proved to be a riskless, secure and time-saving procedure. In our opinion this is a minimal invasive method of treatment for patients with cholecysto-/choledocholithiasis. 相似文献
995.
G. J. CokkinidesD. L. Karabalis 《Advances in Engineering Software》1994,21(3):191-200
The intense computational requirements of a time domain solution of 3-D elastodynamic problems based on the boundary element method (BEM) have limited its implementation to main frame computers. In this work a simplified 3-D direct time domain BEM is described along with a 3-D interactive animated graphics code custom made to accompany the above BEM analysis. The simplifications introduced make its use efficient and accurate even in a microcomputer environment. Representative numerical results from the dynamic interaction of a rigid square machine foundation with an elastic half space are presented. 相似文献
996.
The effect of FEF carbon black as filler on the thermal capacity c, diffusivity a, and thermal conductivity λ, of styrene butadiene rubber (SBR) composites in the temperature range 300–420 K was studied. The filler strongly increases the thermal diffusivity, whilst strongly decreasing the thermal capacity and the thermal conductivity (except at high FEF content ≥80 phr). The influence of the filler on the thermoelastic behaviour of the same composites was also investigated. It was found that the thermoelastic temperature change (ΔT) increased with carbon black concentration as well as the entropy change per unit extension. 相似文献
997.
Samples that are thick with respect to the measuring apparatus can pose problems in the measurement of directional-hemispherical transmittance. Due to the lateral displacement of light that these samples induce, traditional small-beam techniques are often no longer applicable. Broad-area irradiation offers a solution to these problems, but, in practice, imperfections in the extent and the uniformity of the irradiation can create errors. This paper reports measurement of the “detector-integrated inscattering function”, which describes the lateral displacement of light, for a number of thick samples over a range of incidence angles. This function is used to determine the minimum area that must be irradiated for an accurate broad-area irradiation transmittance measurement. The errors caused by transverse non-uniformities in the irradiance distributions produced by a state-of-the-art broad-area irradiation spectrophotometer are also reported. Errors caused by transverse irradiation non-uniformities are estimated, and transmittance measurements made with small-area and broad-area irradiation are compared. It is shown that in most cases small-area irradiation transmittance measurements underestimate the transmittance of thick samples due to outscattering, and that broad-area irradiation measurements using state-of-the-art irradiation optics can contain large errors of up to 20%, due to irradiance non-uniformities, particularly at large angles of incidence. 相似文献
998.
999.
An experimental study of sand-water flow in a horizontal pipeline has been conducted for the regime in which a stationary deposit was present. The particle diameter ranged between 0.2 mm and 0.01 mm and the particles were not flocculated. Axial pressure gradients and delivered concentrations were measured as functions of mean velocity and in-situ concentration.
A three layer model was found to be useful to predict the pipeline behavior at all but the lowest velocities. The Meyer-Peter sediment transport equation was satisfactory for very low velocities with the larger particles. 相似文献
A three layer model was found to be useful to predict the pipeline behavior at all but the lowest velocities. The Meyer-Peter sediment transport equation was satisfactory for very low velocities with the larger particles. 相似文献
1000.