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131.
Identification of Ss protein as murine C4. 总被引:14,自引:0,他引:14
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J. L. Scaro C. Miranda M. A. Carrera B. Martin I. Torrejon 《Cellular and molecular life sciences : CMLS》1984,40(4):348-350
Summary Removal of 15% of blood volume in the mouse increases erythropoiesis by a factor of 2.2 when measured 12 h after bleeding. Exposure of normal mice to 40% reduced barometric pressure for the same period of time increases erythropoiesis only by a factor of 1.6. The response to hypoxia takes place in the presence of a 40% reduction of oxygen consumption and tissue-venous Po
2, changes which are concomitant with a 5-fold increase in plasma erythropoietin activity. The larger response in anemic animals on the other hand occurs without any detectable change in these parameters. These results cast serious doubts about the interpretation of the quantitative homeostatic control of erythropoiesis based solely on the action of erythropoietin.Acknowledgments. This work was supported by a grant from the Consejo Nacional de Investigaciones Científicas y Técnicas de la República Argentina. We thank Isabel Zingariello for excellent technical assistance. 相似文献
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Nandkumar S. Shah L. E. Fox S. P. Martin 《Cellular and molecular life sciences : CMLS》1966,22(10):648-649
Zusammenfassung Bei den tuberkulösen Meerschweinchen wurde in der Niere eine erhöhte Aktivität der Glukose-6-Phosphatase beobachtet. Isoniazid hat die erhöhte Aktivität des Enzyms nicht erniedrigt, wenn es tuberkulösen Tieren vom 8. bis zum 38. Tage nach der Infektion oral verabreicht wurde. Es wird angenommen, dass die erhöhte Aktivität Ausdruck der Adaptionsfähigkeit von Glukose-6-Phosphatase ist.
Galesburg State Research Hospital, Galesburg, Illinois, USA. 相似文献
Galesburg State Research Hospital, Galesburg, Illinois, USA. 相似文献
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Martin Niss 《Archive for History of Exact Sciences》2005,59(3):267-318
I chart the considerable changes in the status and conception of the Lenz-Ising model from 1920 to 1950 in terms of three phases: In the early 1920s, Lenz and Ising introduced the model in the field of ferromagnetism. Based on an exact derivation, Ising concluded that it is incapable of displaying ferromagnetic behavior, a result he erroneously extended to three dimensions. In the next phase, Lenz and Isings contemporaries rejected the model as a representation of ferromagnetic materials because of its conflict with the new quantum mechanics. In the third phase, from the early 1930s to the early 1940s, the model was revived as a model of cooperative phenomena. I provide more detail on this history than the earlier accounts of Brush (1967) and Hoddeson, Schubert, Heims, and Baym (1992) and question some of their conclusions. Moreover, my account differs from these in its focus on the development of the model in its capacity as a model. It examines three aspects of this development: (1) the attitudes on the degree of physical realism of the Lenz-Ising model in its representation of physical phenomena; (2) the various reasons for studying and using it; and (3) the effect of the change in its theoretical basis during the transition from the old to the new quantum mechanics. A major theme of my study is that even though the Lenz-Ising model is not fully realistic, it is more useful than more realistic models because of its mathematical tractability. I argue that this point of view, important for the modern conception of the model, is novel and that its emergence, while perhaps not a consequence of its study, is coincident with the third phase of its development. 相似文献