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Responses of leukocyte, blood glucose and coagulation system in calves were investigated to injection with Escherichia coli endotoxin. Severe leukopenia and hyperglycemia following transient hypoglycemia were noted within 24 hours after injection. In the coagulation system, a definite decrease in platelet count, prolongation of prothrombin time and activated partial thromboplastin time were observed. Fibrinogen, soluble fibrin monomer complex and clotting time, however, varied. 相似文献
43.
DNA polymerase associated with nuclear membrane of calf thymus 总被引:2,自引:0,他引:2
S Yoshida M J Modak K Yagi 《Biochemical and biophysical research communications》1971,43(6):1408-1414
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Tetsuya Tosa Tadashi Sato Takao Mori Yuhsi Matuo Ichiro Chibata 《Biotechnology and bioengineering》1973,15(1):69-84
Various methods were tried for the immobilization of aspartase, and the preparation having the highest activity was obtained when partially purified aspartase from Escherichia coli was entrapped into polyacrylamide gel Iattice. Enzymatic properties of the immobilized aspartase were investigated and compared with those of the native aspartase. With regard to optimum pH, temperature, concentration of Mn++, kinetic constants and heat stability, no marked difference was observed between the native and immobilized aspartases. By employing an enzyme column packed with the immobilized aspartase, conditions for continuous production of L -aspartic acid from ammonium fumarate were investigated. When a solution of 1M ammonium fumarate (pH 8.5, containing 1mM MnCl2) was passed through the aspartase column at the flow rate of SV = 0.08 at 37°C, the highest rate of reaction was attained. From the column effluents, L-aspartic acid was obtained in a good yield. 相似文献
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The physiological changes in green bananas (cv. Sin-zun), which are very sensitive to chilling injury, were studied during and after exposure to low temperatures (4±1°C, 6±0.5°C) for various periods. While the fruits injured by chilling did not fail to produce CO2 and ethylene, the pattern of both CO2- and ethylene production in these chilled fruits (9 and 15 days at 6°C) after transfer to 20°C was not normal. The contents of acetaldehyde and ethanol in chilled fruits, both in peels and pulps, increased with the advance of chilling, injury. There was an accumulation of α-keto acids in the peels of chilled fruits. Only half the conversion of 14C (fed as succinic acid-1, 4-14C) to citric acid and isocitric acid was observed in chilled tissues as compared with healthy ones; the activity of citrate synthase in banana peels appears therefore to be inhibited by chilling injury. A histological study of the tissues showed that the browning substances (polyphenols) present in chilled fruits accumulate around the vascular tissues. 相似文献
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