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251.
S Masumura M Hashimoto Y Hashimoto T Sato I Kihara Y Watanabe 《European journal of applied physiology and occupational physiology》1982,48(2):157-161
Activities of glycolytic enzymes in the aorta were investigated in female Wistar rats. There were two groups of rats; one served as the control (sedentary rats), while the other group was forced to run on a treadmill for 10 weeks. In the control animals, the activities of hexokinase, phosphofructokinase and aldolase were relatively lower than those of the other glycolytic enzymes (phosphoglucose isomerase, lactate dehydrogenase and pyruvate kinase). After exercise, the activity of phosphofructokinase increased by 15%, whereas the other enzymatic activities were much the same as in the controls. Within the limits of the experiments, the increased percentage of phosphofructokinase was statistically significant (p less than 0.05). Since phosphofructokinase is a putative rate limiting enzyme, this enzymatic activation may indicate that glycolytic activity in the rat aorta is enhanced during and after running exercise. 相似文献
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Interactions of luciferases isolated from Vibrio fischeri 6 and Escherichia coli JM109(pF3) (bearing cloned V. fischeri luxAB genes) with FMN reductase isolated from E. coli JM109 were studied. FMN reductase formed a stable complex with luciferase, suggesting similar properties of the FMN reductases in the taxonomically close families Vibrionaceae and Enterobacteriaceae. 相似文献
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The localization of lipid globules was studied in the adrenal glands from 35 fetuses and 10 adult humans by histochemistry. The fetal adrenal showed the presence of numerous lipid globules in the zona glomerulosa, whereas in the adult the lipid globules were mainly found in the zona fasciculata. These lipid globules were confirmed as cholesterol in the fetal adrenals. 相似文献
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Seed germination of Melaleuca ericifolia (swamp paperbark) is delayed by submergence in water but the final percentage germination after removing seeds from water is unaffected; some seeds will germinate and the cotyledons emerge whilst submerged. Germination is totally inhibited at salinities of 14% and a population which naturally occurs adjacent to coastal saltmarsh was inhibited more by salinities of 6–12% than two other populations from freshwater habitats. Seedling growth may be increased by water-logging conditions and the degree of response differs for different seed sources. Inundation stimulates root growth and new roots are thick and aerenchymatous. Root systems in the field run horizontally and are shallow, apparently being restricted by clay at depth. All populations studied showed a similar seedling growth-response to salinity treatments; growth declined at salinities ≤ 13% and was severely restricted at 21%, although no seedlings died after 48 days’exposure to the latter treatment. 相似文献