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971.
972.
Cultivation ofAspergillus niger 97A in baffled flasks on a shaker brings about metabolic changes demonstrated in increased citric acid biosynthesis, morphological
changes and alterations in the mycelial cell wall. 相似文献
973.
K. Lívanský 《Folia microbiologica》1982,27(6):455-459
The buffering capacity of solutions of KH2PO4 and NaHCO3 increases with their concentration, the behaviour being describable by mathematical expressions. Solutions of KH2PO4 prepared from tap water exhibit a buffering capacity higher by an order of magnitude than those prepared from distilled water.
However, there is no difference between the buffering capacities of solutions of NaHCO3 prepared from tap and distilled water. Urea and NH4NO3 have almost no effect on the buffering capacities of sol utions. 相似文献
974.
975.
Dagmar Jičínská Eduard Brabec Marcel Rejmánek Jan Jeník Joří Haager Josef Holub Věroslav Samek Hana Rambousková Josef Holub Marie Naděžda Končalová Robert Neuhäusl Josev Kyncl František Krahuleo Jaroslav Dobrý Blanka Úlehlová Jiří Úlehla Eliška Rybníčková Kamil Rybníček 《Folia Geobotanica》1982,17(4):431-448
976.
977.
Neuro-2a cells incubated for 1 hour with 0.1 mM vanadate showed an increase in cell membrane permeability. This effect is dose dependent, e.g. with 0.01 mM, 0.1 mM and 1 mM vanadate, there was {20, 30 and 40% increase. In contrast, no alteration in permeability was observed in HEp-2 cells under the same conditions.Ethanol (3%, 1 h incubation) also enhanced membrane permeability. The increase was also greater with Neuro-2a cells ({80%) than with HEp-2 cells (~30%). When the cells were incubated with ethanol plus vanadate (0.1 mM), there was a marked potentiation ({200%) in cell membrane permeability in Neuro-2a cells, and again a lesser increase in permeability ({50%) with HEp-2 cells.These results seem to be due to a preferential effect of vanadate on passive permeability of Neuro-2a cells because parallel measurements demonstrate equal inhibition of (Na+K) ATPase with both Neuro-2a and HEp-2 cells. 相似文献
978.
979.
A. Delibes C. Otero F. García-Olmedo F. Dosba 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1981,60(1):5-10
Summary The distribution of three biochemical markers, U-1, CM-4 and Aphv-a, -b, among wheat-Aegilops addition lines carrying Mv chromosomes from Aegilops ventricosa (genomes DvMv) has been investigated. Addition lines which had been previously grouped together on the basis of common non-biochemical characters carried marker U-1, a protein component from the 2M urea extract. The added chromosome, in the appropriate genetic background, seems to confer a high level of resistance to the eyespot disease, caused by the fungus Cercosporella herpotrichoides. The other two markers were concomitantly associated with another similarly formed group of addition lines. Both CM-4, a protein component from the chloroform:methanol extract, and Aphv-a, -b, alkaline phosphate isozymes, have been previously shown to be associated with homoeologous chromosome group 4, which suggests that the added chromosome in the second group of addition lines is 4Mv. 相似文献
980.
The incorporation of radioactive phosphate into phosphatidylinositol was stimulated by epinephrine in hamster fat cells. This action was inhibited by alpha-adrenergic antagonists in the potency order: Prazosin?phentolamine>yohimbine. Methoxamine, but not clonidine, was able to mimic the effect of epinephrine. These data indicate that the phosphatidylinositol effect in fat cells is due to activation of alpha1 adrenoceptors. On the other hand, the accumulation of cyclic AMP due to epinephrine was potentiated by alpha-adrenergic antagonists in the potency order phentolamine>yohimbine ?prazosin, in hamster fat cells. Clonidine significantly decreased the accumulation of cyclic AMP due to isoproterenol or ACTH in hamster fat cells, suggesting that the alpha-adrenergic modulation of cyclic AMP levels in hamster fat cells is mediated by alpha2 adrenoceptors. Radioligand binding studies with plasma membranes from hamster adipocytes demonstrated the presence of both alpha1 and alpha2 adrenoceptors but about 90% of the binding sites were alpha2. These data support the hypothesis that alpha2 effects of catecholamines are due to inhibition of adenylate cyclase while the increases in phosphatidylinositol turnover that seem to be involved in the mobilization of calcium are linked exclusively to alpha1 adrenoceptor activation. 相似文献