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961.
Mary Mitchell Moore 《The Journal of general physiology》1927,8(6):509-518
1. When Cerianthus membranaceus is illuminated upon one side, the animal turns its anterior portion toward the source of light. The number of degrees through which the animal turns is proportional to the logarithm of the intensity of the light. 2. A light intensity of between 250 m.c. and 15,000 m.c. is necessary to cause retraction of the animal. 3. The part of the spectrum which is most effective in causing heliotropic bending of Cerianthus lies between µµ 510 and µµ 570. 相似文献
962.
D. A. Mitchell 《BMJ (Clinical research ed.)》1930,1(3603):144-146
963.
964.
General formulæ are derived for the orientation of phototropic organisms in a field illuminated by two point-sources of light in the same horizontal plane. It is shown that formulæ previously found may all be derived as special cases of these general equations. 相似文献
965.
966.
Mitchell Innes Dick 《BMJ (Clinical research ed.)》1914,1(2781):856-858
967.
968.
969.
M Nakane J Mitchell U F?rstermann F Murad 《Biochemical and biophysical research communications》1991,180(3):1396-1402
Nitric oxide synthase purified from rat brain, which is Ca2+ and calmodulin dependent, was phosphorylated by calcium calmodulin-dependent protein kinase II as well as protein kinase C. Phosphorylation by calcium calmodulin-dependent protein kinase II resulted in a marked decrease in enzyme activity (33% of control) without changing the co-factor requirements, whereas a moderate increase in enzyme activity (140% of control) was observed after phosphorylation by protein kinase C. These findings indicate that brain nitric oxide synthase activity may be regulated not only by Ca2+/calmodulin and several co-factors, but also by phosphorylation. 相似文献
970.
The activating or inhibiting actions of a variety of anion species and of oligomycin, aurovertin and Dio-9 on the ATPase of a sonic particle preparation of rat liver mitochondria have been characterized by measurements of the relevantV
max,K
i
andK
m
values.The normalV
max was increased by a factor near 7 by the anions: dichromate, chromate, pyrophosphate, orthophosphate, orthoarsenate and sulphate. The fully activating concentration varied from about 2 mM for dichromate to 150 mM for sulphate. The increase inV
max was accompanied by a time-dependent decrease in (K
i)ADP, but there was no change in (K
m)ATP. The increase inV
max by the activating anions was abolished by aurovertin; but in presence of oligomycin, the lowV
max was increased by the activating anions by the same factor as theV
max in absence of oligomycin.Certain anions, notably azide, decreasedV
max, but did not affect (K
i)ADP or (K
m)ATP. The decrease inV
max by azide and oligomycin were approximately additive. Even at high concentration, Dio-9 was without detectable effect on the ATPase, but it had a gramicidinlike effect on the intact mitochondria.The specificity of the ATPase for ATP relative to GTP was found to be attributable to the high value of (V
max)ATP compared with (V
max)GTP. The values of (K
m)ATP and (K
m)GTP were virtually the same.Some rationalization of these and other supporting observations is attempted in terms of present knowledge of the constitution of the ATPase complex. 相似文献