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141.
Zusammenfassung Nachweis audiosensibilisierter Anfälle beim HamsterMesocricetus auratus nach Konditionierung auf akustischen Reiz.
Supported in part by grant No. EC 00447-01 from the PHS. We thank Mrs.Barbara Beagle for technical assistance. 相似文献
Supported in part by grant No. EC 00447-01 from the PHS. We thank Mrs.Barbara Beagle for technical assistance. 相似文献
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143.
Dissociation of vertical and horizontal components of activity in rats treated with lithium chloride
F. N. Johnson 《Cellular and molecular life sciences : CMLS》1972,28(5):533-535
Résumé La chlorure de lithium, administré aux rats. a affaibli leur activité verticale, sans porter atteinte à leur activité horizontale. Ces résultats sont compatibles avec l'hypothèse selon laquelle le lithium affaiblit les réponses des animaux aux stimulations. 相似文献
144.
A. S. Weltman A. M. Sackler V. Pandhi L. Johnson 《Cellular and molecular life sciences : CMLS》1976,32(3):357-359
Summary Effects of single doses of 50 and 100 mg/kg of TMA given i.p. were noted in male albino mice after 40 min and 2 1/2 h. Locomotor activity was significantly altered and biochemical tests indicated stimulatory effects on adrenocortical and adrenomedullary functions due to TMA. 相似文献
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Dale M. Johnson 《Archive for History of Exact Sciences》1977,17(3):261-295
This paper treats Bernard Bolzano's (1781–1848) investigations into a fundamental problem of geometry: the problem of adequately defining the concepts of line (or curve), surface, solid, and continuum.
Bolzano's interest in this problem spanned most of his creative lifetime. In this paper a full discussion is given of the philosophical and mathematical motivation of Bolzano's problem as well as his two solutions to the problem. Bolzano's work on this part of geometry is relevant to the history of modern mathematics, because it forms a prelude to the more recent development of topological dimension theory. 相似文献
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Large-scale features of ocean circulation, such as deep water formation in the northern North Atlantic Ocean, are known to regulate the long-term physical uptake of CO2 from the atmosphere by moving CO2-laden surface waters into the deep ocean. But the importance of CO2 uptake into water masses that ventilate shallower ocean depths, such as subtropical mode waters of the subtropical gyres, are poorly quantified. Here we report that, between 1988 and 2001, dissolved CO2 concentrations in subtropical mode waters of the North Atlantic have increased at a rate twice that expected from these waters keeping in equilibrium with increasing atmospheric CO2. This accounts for an extra 0.4-2.8 Pg C (1 Pg = 10(15) g) over this period (that is, about 0.03-0.24 Pg C yr(-1)), equivalent to 3-10% of the current net annual ocean uptake of CO2 (ref. 3). We suggest that the lack of strong winter mixing events, to greater than 300 m in depth, in recent decades is responsible for this accumulation, which would otherwise disturb the mode water layer and liberate accumulated CO2 back to the atmosphere. However, future climate variability (which influences subtropical mode water formation) and changes in the North Atlantic Oscillation (leading to a return of deep winter mixing events) may reduce CO2 accumulation in subtropical mode waters. We therefore conclude that, although CO2 uptake by subtropical mode waters in the North Atlantic--and possibly elsewhere--does not always represent a long-term CO2 sink, the phenomenon is likely to contribute substantially to interannual variability in oceanic CO2 uptake. 相似文献