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131.
Iodination of the exposed Tyr-25 in the coat protein decreases the fluorescence intensity of the filamentous phage Pf1 to less than 3% of its original fluorescence. If one assumes that the total residual fluorescence originates from the non-iodinated, buried Tyr-40, one can estimate the distance between Tyr-40 and the DNA bases in Pf1 to be less than 7 A, making use of the Foerster law for fluorescence energy transfer. The result is consistent with the idea that Tyr-40-DNA interaction is responsible for the unusually large axial base separation in Pf1-DNA. 相似文献
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J. P. van der Walt 《Antonie van Leeuwenhoek》1967,33(1):97-99
The yeast species previously described asPichia robertsii v. d. Walt has been transferred to the new genusWingea. The diagnosis for the genus is given. 相似文献
134.
Preferential expression of cellular retinoic acid binding protein in a subpopulation of neural cells in the developing mouse embryo 总被引:2,自引:0,他引:2
Marie-Josée Vaessen Erika Kootwijk Dirk Bootsma Ad Geurts van Kessel Christine Mummery John Hilkens 《Differentiation; research in biological diversity》1989,40(2):99-105
The cellular retinoic acid binding protein is thought to be involved in the retinoic-acid-mediated signal transduction pathway. We have isolated the mouse cellular retinoic acid binding protein cDNA from an embryonal-carcinoma-derived cell line by using differential cDNA cloning strategies. In situ hybridization on sections of mouse embryos of various developmental stages indicated that the cellular retinoic acid binding protein gene, which we localized on mouse chromosome 9, is preferentially expressed in a subpopulation of neurectodermal cells. This restricted expression pattern suggests an important role for cellular retinoic acid binding protein in murine neurogenesis. 相似文献
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Evidence from eleven samples indicates that the mean IQ of third world immigrants in the Netherlands is lower than the Dutch mean by approximately one standard deviation for Surinamese and Antillians, and by approximately one and a half standard deviations for Turks and Moroccans. Since IQ tests provide the best prediction of success in school and organizations, it could be that the immigrants' lower mean IQ is an important factor in their low status on the Dutch labour market. The IQs of second-generation immigrants are rising. 相似文献