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Interaction between the Effects of Inside and Outside Na and K on Bullfrog Skin Potential 总被引:2,自引:1,他引:1
Daniel E. Leb Charles Edwards Barry D. Lindley T. Hoshiko with the technical assistance of James A. Dugan 《The Journal of general physiology》1965,49(2):309-320
The composition of the solution bathing one border of the isolated frog skin affects the response of the potential across the skin to changes in the composition of the solution bathing the opposite border. Increasing the K concentration of the inside (corium) bathing solution decreased the sensitivity of the potential to a change in outside Na concentration. Decreasing the outside Na concentration decreased the sensitivity of the potential to a change in inside K concentration. Increasing the total ionic strength of the outside bathing solution or of both bathing solutions decreased the sensitivity of the potential to a change in outside Na concentration. 相似文献
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Aiyi Liu James F. Troendle Kai F. Yu Vivian W. Yuan 《Biometrical journal. Biometrische Zeitschrift》2004,46(6):760-768
We consider estimation after a group sequential test. An estimator that is unbiased or has small bias may have substantial conditional bias (Troendle and Yu, 1999, Coburger and Wassmer, 2001). In this paper we derive the conditional maximum likelihood estimators of both the primary parameter and a secondary parameter, and investigate their properties within a conditional inference framework. The method applies to both the usual and adaptive group sequential test designs. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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James R. Troyer 《American journal of botany》1992,79(7):833-841
Historians and others have given attention to multiple independent discoveries because of their implications for the nature of scientific discovery in general. However, previously published lists of such discoveries include almost no examples from botany. That this has been a matter of oversight is shown by the presentation of 22 cases of multiple botanical discoveries, the circumstances of which are briefly described. These examples show a number of the same general characteristics as those in other fields of science. They range in importance from the broadly sweeping to the narrowly specific, and show various degrees of simultaneity. They illustrate the problems of interpretation involved in judging functional equivalence, identity of central message, and priority. The bearing of some of the examples on various theories of the cause of multiple discoveries is also discussed. It is concluded that multiple discoveries have probably occurred as frequently in botany as in other sciences, and they display the same characteristics and generate the same problems of interpretation. 相似文献
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James W. Green 《American anthropologist》2000,102(1):195-196
The Last Passage: Recovering. Death of Our Own. Donald Heinz. New York: Oxford University Press. 1999. 296 pp. 相似文献
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