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61.
Anna Castro Carles Codony Ramon Eritja 《Nucleosides, nucleotides & nucleic acids》2013,32(12):2189-2197
Abstract A hybridoma against the nucleoside m6A has been obtained from mouse spleen. This hybridoma was named H65 and it secretes monoclonal antibodies anti-m6A. The competition assays showed that the monoclonal antibody was highly specific for m6A nucleoside. 相似文献
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Anna Maria Aviñó Adrian Mayordomo Ruth Espuny Montse Bach Ramon Eritja 《Nucleosides, nucleotides & nucleic acids》2013,32(7):1613-1617
Abstract The preparation of N2, N2-dimethylguanosine is described. The use of the 2-(p-nitrophenyl)ethyl group instead of the benzyl protecting group for the O6 position of the guanine ring resulted in better yields and shorter protocols. 相似文献
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Beatriz G. de la Torre Anna Maria Aviñó Mónica Escarceller Miriam Royo Fernando Albericio Ramon Eritja 《Nucleosides, nucleotides & nucleic acids》2013,32(9):993-1005
Abstract The preparation of a base-labile (Dnpe) protected derivative of 6-mercaptohexanol is described. The use of the phosphoramidite derivative of this compound improves both yields and the time needed for the preparation of oligonucleotides containing a thiol group at the 5′-end. 相似文献
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Jana Selent Agnieszka A. Kaczor Ramon Guixà-González Pau Carrió Manuel Pastor Cristian Obiol-Pardo 《Journal of molecular modeling》2013,19(4):1507-1514
Survivin, the smallest inhibitor of apoptosis protein (IAP), is a valid target for cancer research. It mediates both the apoptosis pathway and the cell cycle and has been proposed to form a complex with the cyclin-dependent kinase protein CDK4. The resulting complex transports CDK4 from the cytosol to the nucleus, where CDK4 participates in cell division. Survivin has been recognized as a node protein that interacts with several partners; disruption of the formed complexes can lead to new anticancer compounds. We propose a rational model of the survivin/CDK4 complex that fulfills the experimental evidence and that can be used for structure-based design of inhibitors modifying its interface recognition. In particular, the suggested complex involves the alpha helical domain of survivin and resembles the mode of binding of survivin in the survivin/borealin X-ray structure. The proposed model has been obtained by combining protein–protein docking, fractal-based shape complementarity, electrostatics studies and extensive molecular dynamics simulations. Figure
Proposed model of the survivin/CDK4 complex with a close view of the best model refined through molecular dynamics simulations 相似文献
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It is well-known that word frequencies arrange themselves according to Zipf''s law. However, little is known about the dependency of the parameters of the law and the complexity of a communication system. Many models of the evolution of language assume that the exponent of the law remains constant as the complexity of a communication systems increases. Using longitudinal studies of child language, we analysed the word rank distribution for the speech of children and adults participating in conversations. The adults typically included family members (e.g., parents) or the investigators conducting the research. Our analysis of the evolution of Zipf''s law yields two main unexpected results. First, in children the exponent of the law tends to decrease over time while this tendency is weaker in adults, thus suggesting this is not a mere mirror effect of adult speech. Second, although the exponent of the law is more stable in adults, their exponents fall below 1 which is the typical value of the exponent assumed in both children and adults. Our analysis also shows a tendency of the mean length of utterances (MLU), a simple estimate of syntactic complexity, to increase as the exponent decreases. The parallel evolution of the exponent and a simple indicator of syntactic complexity (MLU) supports the hypothesis that the exponent of Zipf''s law and linguistic complexity are inter-related. The assumption that Zipf''s law for word ranks is a power-law with a constant exponent of one in both adults and children needs to be revised. 相似文献
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