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Host-dependent restriction of influenza B virus replication in L cells was analysed in comparison with productive infection in MDCK or 1–5C-4 cells. The synthesis and intracellular distribution of virus-specific proteins and the production of cytoplasmic ribonucleoproteins in nonpermissive L cells were similar to those in permissive MDCK cells. However, an electron microscopic study of infected L cells showed neither extracellular virions nor budding virus particles on the cell surface, in contrast to MDCK cells which produced numerous virus particles. PAGE analysis of the plasma membrane isolated from the cells demonstrated no significant difference in the composition of viral polypeptides between permissive 1-5C-4 and nonpermissive L cells. It was noted that the abortiveness of influenza B virus infection in L cells may be due to a defect in host cell function involved in the initiation of virus budding.  相似文献   
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Journal of Biomolecular NMR - Solid-state NMR spectroscopy is a powerful technique to study insoluble and non-crystalline proteins and protein complexes at atomic resolution. The development of...  相似文献   
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Melissococcus plutonius is a fastidious honeybee pathogen, and the addition of KH2PO4 to culture medium is required for its growth. Using genome sequences and a newly developed vector, we showed that mutations in genes encoding Na+/H+ antiporter and cation-transporting ATPase are involved in the potassium requirement for growth.  相似文献   
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The Saccharinae, especially sugarcane, Miscanthus and sorghum, present remarkable characteristics for bioenergy production. Biotechnology of these plants will be important for a sustainable feedstock supply. Herein, we review knowledge useful for their improvement and synergies gained by their parallel study.  相似文献   
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The second (index finger) to fourth (ring finger) digit length ratio (2D:4D) is known to be a putative marker of prenatal exposure to testosterone. It has been reported that fetal and adult testosterone may be critical for development of physical and mental traits such as cardiovascular system, reaction time, aggressiveness and masculinity. Testosterone-driven attributes are associated with success in male-to-male physical competition, which may be proxied by ability in sports. Many researchers have found that 2D:4D is sexually dimorphic and is a negative correlate of athletic performance. This study aims to investigate the associations of 2D:4D with measures of power as another possible testosterone-associated trait using ability in sumo wrestling as a proxy for male physical competitiveness. The measures of sumo performance comprised the sumo ranks and winning percentages of 142 Japanese professional sumo wrestlers. We found that sumo wrestlers with low 2D:4D had higher sumo ranks and better winning records. The significant negative associations between 2D:4D and the athletic prowess of sumo wrestlers provide further evidence of the possible link between high testosterone levels and muscle strength. The relatively small effect sizes found in this study, however, imply that 2D:4D may be a weaker predictor for sports requiring explosive power than for those requiring endurance.  相似文献   
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