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991.
Y. Komai H. Sato N. Hiraiwa Y. Sawaishi 《Cellular and molecular life sciences : CMLS》1971,27(8):881-882
Zusammenfassung Wasserlösliche, proteolipide Proteine wurden von der weissen Hirnsubstanz durch Isolierungsmethoden vonTenenbaum undFolch
2 gewonnen. Ohne Lyophilisation ergab die Disk-Elektrophorese bei pH 8.3 zwei Banden.
The authors express their appreciation to Dr.K. Ueki, Dr.Y. Takahashi, Dr.Y. Takemoto and Dr.T. Kotoku. 相似文献
The authors express their appreciation to Dr.K. Ueki, Dr.Y. Takahashi, Dr.Y. Takemoto and Dr.T. Kotoku. 相似文献
992.
When we see motion, our perception of how one image feature moves depends on the behaviour of other features nearby. In particular, the Gestaltists proposed the law of shared common fate, in which features tend to be perceived as moving together, that is, coherently. Recent psychophysical findings, such as the cooperativity of the motion system and motion capture, support this law. Computationally, coherence is a sensible assumption, because if two features are close then they probably belong to the same object and thus tend to move together. Moreover, the measurement of local motion may be inaccurate and so the integration of motion information over large areas may help to improve the performance. Present theories of visual motion, however, do not account fully for these coherent motion percepts. We propose here a theory that does account for these phenomena and also provides a solution to the aperture problem, where the local information in the image flow is insufficient to specify the motion uniquely. 相似文献
993.
Résumé Nous décrivons des inclusions cristallines observées dans l'élytre extracellulaire des glandes venimeuses deLoxosceles reclusa. 相似文献
994.
995.
A new experimental model of glucocorticoid-induced tubular cyst formation has been developed in metanephric organ culture. The addition of cortisol (1.4 X 10(-5) M) to chemically defined serum-free culture medium produces cystic changes during in vitro nephrogenesis . The model isolates the role of glucocorticoids in experimental cyst formation. 相似文献
996.
Kato Y. Fusetani N. Matsunaga S. Hashimoto K. 《Cellular and molecular life sciences : CMLS》1986,42(11-12):1299-1300
Cellular and Molecular Life Sciences - Two novel furanosesterterpenes, okinonellins A (1) and B (2), have been isolated from the spongeSpongionella sp. Both compounds inhibit cell division of... 相似文献
997.
998.
Cellular and Molecular Life Sciences - 相似文献
999.
Identification of the V factor needed for synthesis of the iron-molybdenum cofactor of nitrogenase as homocitrate 总被引:5,自引:0,他引:5
T R Hoover A D Robertson R L Cerny R N Hayes J Imperial V K Shah P W Ludden 《Nature》1987,329(6142):855-857
Nitrogenase catalyses the ATP-dependent reduction of N2 to NH3, and is composed of two proteins, dinitrogenase (MoFe protein or component I) and dinitrogenase reductase (Fe protein or component II). Dinitrogenase contains a unique prosthetic group (iron-molybdenum cofactor, FeMoco) comprised of Fe, Mo and S, which has been proposed as the site of N2 reduction. Biochemical and genetic studies of Nif- (nitrogen fixation) mutants of Klebsiella pneumoniae which are defective in nitrogen fixation, have shown that the nifB, nifQ, nifN, nifE and nifV genes are required for the biosynthesis of FeMo-co. Recently, a system for in vitro synthesis of FeMoco was described. The assay requires at least the nifB, nifN and nifE gene products, and a low-molecular-weight factor (V factor) produced in the presence of the nifV gene product. We have used this system to study FeMoco biosynthesis. We report here the isolation of V factor and identify it as homocitric acid ([R]2-hydroxy-1,2,4-butanetricarboxylic acid). 相似文献
1000.
Cholera toxin genes: nucleotide sequence, deletion analysis and vaccine development 总被引:25,自引:0,他引:25
Nucleotide sequence and deletion analysis have been used to identify the regulatory and coding sequences comprising the cholera toxin operon (ctx). Incorporation of defined in vitro-generated ctx deletion mutations into Vibrio cholerae by in vivo genetic recombination produced strains which have practical value in cholera vaccine development. 相似文献