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101.
According to FDA regulations, a combination drug is not efficacious unless each component contributes to the claimed effects. For a univariate endpoint, this implies that the combination at specific doses must be superior to each of its components at the same doses. More demanding is the property of synergy, in which the effect of the combination must be superior to the effect expected based on those of its components. If it is equal to those effects, it is additive, and if it is inferior, it is antagonistic. We give regions in the combination dose plane where these concepts are well defined. If the effect of the combination is greater than the greatest effect achievable by any of its components it is therapeutically synergistic. A combination can be antagonistic, yet its components can still contribute to the claimed effects. If it is additive, synergistic or therapeutically synergistic, its components must contribute to the claimed effects. We relate these concepts and provide designs and sequential procedures for determining whether a combination is therapeutically synergistic, synergistic, additive, antagonistic and contributing or antagonistic and non-contributing. 相似文献
102.
一类动态大系统的协调控制模型 总被引:12,自引:0,他引:12
讨论了一类离散动态大系统的协调控制问题,提出了相应的模型辨识方法及自适应协调控制算法。通过仿真实例,说明效果是良好的。 相似文献
103.
Zinc sulphide thin film electroluminescent devices doped with Mn or Tb have been produced on p-type Si substrates using a process in which doped zinc oxide films are deposited by a sol-gel drain coating method from a solution of zinc acetate containing a manganese or terbium dopant. The films are then converted to ZnS by heating them in an atmosphere containing hydrogen sulphide which replaces the oxygyn with sulphur. The composition, crystalline structure and optical properties of films have shown that complete conversion from the oxide to the sulphide takes place. The luminescent characteristics of the devices so produced have been measured as a function of the doping concentrations, film thickness, insulator thickness and driving voltage and frequency. It has been found that yellow or green luminescence can be obtained using Mn or Tb doping respectively. 相似文献
104.
粉末材料中微夹杂缺陷的超声波检验 总被引:1,自引:0,他引:1
介绍了用超声波方法检测微夹杂缺陷的一些试验结果,比较了不同频率、不同试验方法检测能力的差异,并通过解剖试验对检出缺陷的性质、尺寸作了比较。 相似文献
105.
106.
107.
唐大宏 《计算机工程与设计》1994,(2):60-64,F003,F00
依据物体透视图的人工作图法,本文提出了确定透视变换矩阵的新方法,这种方法基于一组新的参数,而每个参数与透视变换的结果有明显关系,因此便于使用,并给出了计算机作图示例。 相似文献
108.
本文介绍智能控制在回转窑配料系统中的应用情况,并阐述该控制器设计、构成、软件系统特点及现场运行效果。 相似文献
109.
110.
To investigate the pathogenicity of Aspergillus fumigatus mutants lacking putative virulence factors, we have developed a new murine model of invasive pulmonary aspergillosis based on neutropenia, the major factor predisposing patients to this infection. Mice were treated with cyclophosphamide and inoculated by the intranasal route with 5 x 10(3) conidia, a significant reduction from inoculum levels used in previous models. Evidence for the production of the extracellular alkaline protease (Alp) in lung tissue was obtained by using a fungal transformant harboring an alp::lacZ reporter gene fusion. The pathogenicities of single mutant strains lacking either Alp or the ribotoxin restrictocin and of a double mutant strain lacking both proteins were assessed in this infection model. There were no significant differences between the mutant and the wild-type strains in terms of mortality or histological-features. Inoculations with mixtures of conidia showed that the double mutant strain is slightly less virulent than the wild-type strain. We conclude that Alp and restrictocin are not important virulence determinants in pulmonary infection. 相似文献