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Platelet factor 3 availability in bleeder swine 总被引:1,自引:0,他引:1
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Hilary E. Kahn 《American anthropologist》1998,100(1):230-231
Tlie Two Milpas of Chan Kom:. Study of Socioeconomic and Political Transformations in. Maya Community. Alicia Re Cruz. Albany: State University of New York Press, 1996. 203 pp. 相似文献
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In vivo developmental modifications of the expression of genes encoding muscle-specific enzymes in rat 总被引:2,自引:0,他引:2
F Schweighoffer P Maire D Tuil S Gautron D Daegelen L Bachner A Kahn 《The Journal of biological chemistry》1986,261(22):10271-10276
cDNA clones for rat muscle-type creatine kinase and glycogen phosphorylase and aldolase A were isolated from a rat muscle cDNA library. An additional clone recognizing an unidentified 2.7-kilobase pair mRNA species was also isolated. These cDNA clones were used as probes to investigate the expression of the corresponding mRNAs during muscle development. Two aldolase A mRNA species were detected, one of 1650 bases expressed in non-muscle tissues, fetal muscle, and adult slow-twitch muscle, the other of 1550 bases was highly specific of adult fast-twitch skeletal muscle differentiation. These aldolase A mRNAs were shown by primer extension to differ by their 5' ends. The accumulation of muscle-type phosphorylase and creatine kinase and muscle-specific aldolase A mRNA accumulation during muscle development seems to be a coordinate process occurring progressively from the 17th day of intrauterine life up to the 30th day after birth. In contrast, the 2.7-kilobase pair RNA species is maximally expressed at the 1st week after birth as is the neonatal form of myosin heavy chain mRNA. 相似文献
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This paper describes experimental tests of the hypothesis that bacteriorhodopsin (BR) can fold by the association of independently stable transmembrane helices. Peptides containing the first and second helical segments of BR were chemically synthesized. These two peptides and the complementary five-helix fragment of BR were reconstituted in three separate populations of native-lipid vesicles which were then mixed and fused to allow the fragments to interact. After addition of retinal, absorption spectroscopy of the reconstituted BR and X-ray diffraction of two-dimensional crystals of this material showed that the native structure of BR was regenerated. The first two helices of BR can therefore be considered as independent folding domains, and covalent connections in the loops connecting the helices to each other and to the rest of the molecule are not essential for the appropriate association of the helices. 相似文献