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11.
I Martínez de Mara?ón N Chaudanson N Joly P Gervais 《Biotechnology and bioengineering》1999,65(2):176-181
Thermal resistance of Saccharomyces cerevisiae was found to be drastically dependent on the kinetics of heat perturbation. Yeasts were found to be more resistant to a plateau of 1 h at 50 degrees C after a slope of temperature increase (slow and linear temperature increments) than after a shock (sudden temperature change). Thermotolerance was mainly acquired between 40-50 degrees C during a heat slope, i.e., above the maximal temperature of growth. The death of the yeasts subjected to a heat shock might be related to the loss of membrane integrity: intracellular contents extrusion, i.e., membrane permeabilization, was found to precede cell death. However, the permeabilization did not precede cell death during a heat slope and, therefore, membrane permeabilization was a consequence rather than a cause of cell death. During a slow temperature increase, yeasts which remain viable may have time to adapt their plasma membrane and thus maintain membrane integrity. 相似文献
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cand. phil. Franz Matouschek 《Plant Systematics and Evolution》1894,44(5):177-178
Ohne Zusammenfassung 相似文献
14.
Acta Biotheoretica - Author continues the publication which appeared in the Acta Biotheoretica I, p. 113–132, regarding his results obtained in course of research work on superior... 相似文献
15.
Franz Frimmel 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1937,9(6-7):173-177
Ohne Zusammenfassung 相似文献
16.
Franz M. Wuketits 《Biology & philosophy》1986,1(2):191-206
Recently, biologist and philosophers have been much attracted by an evolutionary view of knowledge, so-called evolutionary epistemology. Developing this insight, the present paper argues that our cognitive abilities are the outcome of organic evolution, and that, conversely, evolution itself may be described as a cognition process. Furthermore, it is argued that the key to an adequate evolutionary epistemology lies in a system-theoretical approach to evolution which grows from, but goes beyond, Darwin's theory of natural selection. 相似文献
17.
Ulrike Rosenfellner Franz Zehetner Martin H. Gerzabek 《Soil & Sediment Contamination》2009,18(6):685-687
Data from eight published studies were combined to show that the influence of traffic density on Pb contents in roadside soils increases with proximity to the road. 相似文献
18.
A Soler C García del Río L García-Torres F Vargas A Martín-Andrés C Osorio 《Revista Espanola de Fisiología》1985,41(1):107-116
The effects of changes in arterial pressure and in circulating volume on Plasma Renin Activity (PRA) in the intact rat were compared by two experimental procedures. Gradual volume depletion was induced by intraperitoneal injection of a hyperoncotic polyethyleneglycol solution (PEG) in absence of acute changes in Systolic Arterial Pressure (SAP). SAP was measured in the conscious state by the tail cuff technique. Plasma Protein Concentration (PPC) and Hematocrit (Hct) increases after PEG injection were compared as the index for measuring the Plasma Volume Reduction (PVR). PRA showed a significant (p less than 0.001) linear relationship with PPC, suggesting a direct dependence of renin secretion on volume depletion. Acute changes in the circulating volume were induced by controlled hemorrhages of 5.0, 10.0, 15.0 and 20.0 ml of blood/kg body weight. The increase in PRA showed a significant relationship with the changes in circulating volume, but it did not show any dependence on the changes in Mean Arterial Pressure (MAP). Our results suggest that, in the intact and conscious rat, renin secretion responds to the information from the cardiopulmonary volume receptors rather than to that from the high pressure receptors. 相似文献
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The histologic properties of pleural adipose organs were studied in 14 newborns. These organs contain milky spots, in which lymphocytes, macrophages and plurivacuolated fat cells are present. The milky spots have a mesothelial covering, persist to the age of 9 months and seem to act as defence devices and a site of fluid exchange. 相似文献