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61.
The frog transgenesis technique ultimately promises to make mutagenesis possible through random insertion of plasmid DNA into the genome. This study was undertaken to evaluate whether a gene trap approach combined with transgenesis would be appropriate for performing insertional mutagenesis in Xenopus embryos. Firstly, we confirmed that the transgenic technique results in stable integration into the genome and that transmission through the germline occurs in the expected Mendelian fashion. Secondly, we developed several gene trap vectors, using the green fluorescent protein (GFP) as a marker. Using these vectors, we trapped several genes in Xenopus laevis that are expressed in a spatially restricted manner, including expression in the epiphysis, the olfactory bulb and placodes, the eyes, ear, brain, muscles, tail and intestine. Finally, we cloned one of the trapped genes using 5' rapid amplification of cDNA ends polymerase chain reaction (RACE PCR). These results suggest that the transgenic technique combined with a gene trap approach might provide a powerful method for generating mutations in endogenous genes in Xenopus. 相似文献
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Arán VJ Ochoa C Boiani L Buccino P Cerecetto H Gerpe A González M Montero D Nogal JJ Gómez-Barrio A Azqueta A López de Ceráin A Piro OE Castellano EE 《Bioorganic & medicinal chemistry》2005,13(9):3197-3207
A series of new 3-alkoxy- or 3-hydroxy-1-[omega-(dialkylamino)alkyl]-5-nitroindazoles have been synthesized and their trichomonacidal, antichagasic and antineoplastic properties studied. Five derivatives (5, 6, 8, 9 and 17) showed remarkable trichomonacidal activity against Trichomonas vaginalis at 10 microg/mL concentration. Three compounds (8, 10, 11) exhibited interesting antichagasic activity and these same compounds moderate antineoplastic activity against TK-10 and HT-29 cell lines. Unspecific cytotoxicity against macrophages has also been evaluated and only compounds 9, 10 and 11 resulted cytotoxic at the higher dose evaluated (100 microg/mL), loosing cytotoxicity at lower doses. QSAR studies have been carried out. X-ray crystallographic study of compound 8 has been performed. 相似文献
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Isolation of a yeast gene, SRH1, that encodes a homologue of the 54K subunit of mammalian signal recognition particle 总被引:12,自引:0,他引:12
A 1.7 kilobase HindIII fragment of Saccharomyces cerevisiae DNA was cloned by cross-hybridization with the Escherichia coli secY gene. The complete nucleotide sequence of the 2.6 kb fragment of the yeast genomic DNA containing the cross-hybridizing HindIII fragment was determined. The sequence showed no apparent similarity with that of the E. coli secY gene with the exception of a completely matched sequence of 21 bp, but it contained a 1,623 nucleotide open reading frame coding for a protein of 541 amino acids with a calculated Mr of 59,600. The N-terminal portion of 303 residues of the predicted sequence was homologous to the cytosolic domain of the alpha-subunit of the signal recognition particle receptor (SR alpha), including consensus sequence elements for a GTP binding site, whereas the C-terminal portion of 238 residues had an unusual methionine-rich domain containing several repetitive sequences. An mRNA of 2.0 kb was detected on Northern blotting analysis. The predicted sequence was 48% identical with the reported sequences of the 54K subunit of the mammalian signal recognition particle (SRP54) (Romisch K. et al. (1989) Nature 340, 478-483; Bernstein, H.D. et al. (1989) Nature 340, 482-486). We designated this gene as SRH1 (SRP54 homologue). Gene disruption experiments showed that the SRH1 gene product is essential for cell growth. 相似文献
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Roberto Fraile Ana Isabel Calvo Amaya Castro Delia Fernández-González Eduardo García-Ortega 《Aerobiologia》2006,22(1):35-45
Long-range transport of gases and aerosols depends on vertical and horizontal air shifts: studies on atmospheric transport
have to be based on the meteorological conditions of the environment. The aim of this paper is to review the physical principles
on which meteorological models are based, and to make an exhaustive inventory of the main models used for the prognosis and
diagnosis of air masses and a list of the long-range transport models associated to them. URL addresses are provided for all
of these models to allow the reader to check their usefulness. A practical application is included with reference to trajectories
followed by air masses that reach the Iberian Peninsula at various altitudes, depending on the synoptic meteorological situation.
Further examples describe air masses entering Europe with desert dust from Africa. This dust may eventually develop into freezing
nuclei and form hailstones in summer storms. 相似文献
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Fibroblast growth factor (FGF) signalling has been implicated during several phases of early embryogenesis, including the patterning of the embryonic axes, the induction and/or maintenance of several cell lineages and the coordination of morphogenetic movements. Here, we summarise our current understanding of the regulation and roles of FGF signalling during early vertebrate development. 相似文献
70.
Wang Jiaqiu Fang Runxin Wu Hao Xiang Yuqiao Mendieta Jessica Benitez Paritala Phani Kumari Fan Zhenya Anbananthan Haveena Amaya Catano Jorge Alberto Raffel Owen Christopher Li Zhiyong 《Biomechanics and modeling in mechanobiology》2023,22(2):729-738
Biomechanics and Modeling in Mechanobiology - It remains unknown that the degree of bias in computational fluid dynamics results without considering coronary cyclic bending. This study aims to... 相似文献