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排序方式： 共有8847条查询结果，搜索用时 31 毫秒
991.
Richard C. Nairn M.D. Ph.D. F.R.C.Path. F.R.C.P.A. F.R.A.C.P. F.R.S.E. Jennifer M. Rolland B.Sc. Ph.D. 《Endeavour》1981,5(4):167-171
Fluorescent dyes can be used as cell probes which bind, according to their chemical structure, to particular subcellular regions of lymphocytes. Because of their sensitivity to variations in the local molecular environment, expressed by changes in fluorescence emission, they provide a means of studying the early events of lymphocyte activation to antigens and mitogens. The technology also yields a rapid assay of lymphocyte activation and thus new diagnostic tests of cell-mediated immunity, for example to organ transplants and to cancer. 相似文献
992.
993.
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This paper establishes a clear procedure for the variational problem solution via the Walsh functions.technique. First the Walsh functions are introduced and their properties briefly summarized. Then an operational matrix is derived for integration use. The variational problems are solved by means of the direct method using the Walsh series. An illustrative example and a practical application to a heat conduction problem are included. 相似文献
995.
996.
Heat transfer in laminar tube flow with convective boundary conditions and axial heat conduction in the fluid is solved exactly. The effects of the external Biot numbers and the axial conduction in fluid on the temperature distribution and the local Nusselt number are determined for both the upstream and the downstream regions. In order to illustrate the effects of velocity profile, the results for the slug flow and the parabolic velocity profiles are plotted simultaneously. The heat transfer characteristics of the flow are found to be rather sensitive to the Péclét number, the external Biot numbers and the velocity profile in the thermal entrance region. 相似文献
997.
998.
F.M. Reza 《Journal of The Franklin Institute》1981,312(5):335-343
Dissipative operators appear in abundance in the study of dynamical systems. In the classical circuit theory they are presented as Positive Real Functions. The coefficients of the Taylor expansion of PRF (driving-point impedance or admittance) must satisfy certain derived inequalities. A method is suggested for obtaining restrictions of the derivative of Positive Real Functions (Dissipative Operators). 相似文献
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1000.