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991.
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W J Koopman M H Gillis J R David 《Journal of immunology (Baltimore, Md. : 1950)》1973,110(6):1609-1614
995.
996.
Comparison of the three basic scattering functions of myoglobin in solution with those from the known structure in crystalline state 总被引:2,自引:0,他引:2
H B Stuhrmann 《Journal of molecular biology》1973,77(3):363-369
X-ray small-angle scattering of myoglobin in aqueous solutions enhances the probability that the structure of myoglobin is conserved on passing to the dissolved state. The agreement of measured and calculated results could be extended up to which roughly corresponds to 5 Å resolution. 相似文献
997.
The lipid composition of swimming spores, cysts and five hour germlings was established. Spores utilized triglycerides first, then phospholipids. Upon encystment all glycolipid components decreased, while in germlings the phospholipids, monoglycerides and sterol esters exhibited a marked increase. 相似文献
998.
H. Uehleke 《Mutation research》1974,25(2):159-167
An overview on aspects of kinetics and properties of reactive drug metabolites in relation to mutagenesis. 相似文献
999.
R B Reisberg 《Life sciences》1974,14(10):1965-1973
Choline acetyltransferase activity in homogenates, or in partially purified extracts of rat brain cerebra, was increased by 11–37% in the presence of ethanol when incubated at 38°C with [14C] acetyl-CoA, choline chloride and alcohol concentrations of 0.17M to 1.02M. In preincubation experiments with enzyme preparations and ethanol, inactivation of the enzyme by the alcohol, which occurs at incubation times longer than 20 minutes, could be at least partially prevented by the addition of certain components of the incubation mixture to the preincubation mixture. 相似文献
1000.
This study was conducted to determine if amplitudes of rat corticol steady potential (SP) response to an auditory stimulus could be altered by operant conditioning procedures using food reinforcement. The negative SP responses to the 5-sec tone alone diminished with repeated presentation of the stimulus. When food reinforcement was given immediately following the tone, SP response amplitudes increased and stabilized after 4–5 sessions. Thereafter, the animals were required to increase or decrease the amplitudes of response in order to obtain reinforcement. Two of three rats required to increase amplitudes were successful and three of four rats required to decrease amplitudes were successful. It is concluded that changes in cortical SP responses can be operantly conditioned. 相似文献