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1.
Cdk1 is sufficient to drive the mammalian cell cycle 总被引:1,自引:0,他引:1
Santamaría D Barrière C Cerqueira A Hunt S Tardy C Newton K Cáceres JF Dubus P Malumbres M Barbacid M 《Nature》2007,448(7155):811-815
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Julie Patenaude Michele D’Elia Claudine Hamelin Jacques Bernier 《Cellular and molecular life sciences : CMLS》2010,67(8):1315-1329
Burn injury causes an immunosuppression associated with suppressed adaptive immune function. Dendritic cells (DCs) are APCs
for which signaling via their Toll-like receptors (TLRs) induces their maturation and activation, which is essential for the
adaptive immune response. In this study, we examined if burn injury alters the TLR activity of splenic DCs. After injury,
we noticed that DC functions were impaired, characterized by a suppressed capacity to prime naive T cells when triggering
the TLR4 signaling cascade using specific ligands (LPS or rHSP60). The observed perturbations on LPS-primed DCs isolated from
burned mice exhibited significantly diminished IL-12p40 production and enhanced IL-10 secretion-associated impairment in mitogen-activated
protein kinase activation. Interestingly, we observed a decrease of TLR4/MD-2 expression on the CD8α+ DC subset that persisted following LPS stimulation. The altered TLR4 expression on LPS-stimulated CD8α+ DCs was associated with reduced capacity to produce IL-12 after stimulation. Our results suggested that TLR4 reactivity on
DCs, especially CD8α+ DCs, is disturbed after burn injury. 相似文献
3.
XIEZhihong YANGYi PINGShuzheng CHENMing ZHANGwei LUWei XUYuquan LIUHongjuan WANGGuoying E.Claudine LINMin 《科学通报(英文版)》2005,50(2):190-192
Pseudomonas stutzeri AI501 (formerly Alcaligenes faecalis A1501), which was isolated from rice paddies in South China in 1980, can colonize tightly on rhizoplane of the host plants or invade the roots of plants for growth and nitrogen fixation. But A1501 can fix nitrogen only under the micro-aerobic and nitrogen-free conditions. The oxygen concentration and the availability of fixed nitrogen are therefore important factors in the regulation of nitrogenase biosynthesis of associative nitrogen-fixing bacteria. 相似文献
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Fulchignoni M Ferri F Angrilli F Ball AJ Bar-Nun A Barucci MA Bettanini C Bianchini G Borucki W Colombatti G Coradini M Coustenis A Debei S Falkner P Fanti G Flamini E Gaborit V Grard R Hamelin M Harri AM Hathi B Jernej I Leese MR Lehto A Lion Stoppato PF López-Moreno JJ Mäkinen T McDonnell JA McKay CP Molina-Cuberos G Neubauer FM Pirronello V Rodrigo R Saggin B Schwingenschuh K Seiff A Simões F Svedhem H Tokano T Towner MC Trautner R Withers P Zarnecki JC 《Nature》2005,438(7069):785-791
On the basis of previous ground-based and fly-by information, we knew that Titan's atmosphere was mainly nitrogen, with some methane, but its temperature and pressure profiles were poorly constrained because of uncertainties in the detailed composition. The extent of atmospheric electricity ('lightning') was also hitherto unknown. Here we report the temperature and density profiles, as determined by the Huygens Atmospheric Structure Instrument (HASI), from an altitude of 1,400 km down to the surface. In the upper part of the atmosphere, the temperature and density were both higher than expected. There is a lower ionospheric layer between 140 km and 40 km, with electrical conductivity peaking near 60 km. We may also have seen the signature of lightning. At the surface, the temperature was 93.65 +/- 0.25 K, and the pressure was 1,467 +/- 1 hPa. 相似文献
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Summary The main constituent of bone salts, which has a Ca/P ratio of 2,26, contains 10 calcium per 6 phosphorus, plus half an atom of calcium which properties are important to be known. This half atom has the same behaviour as the other calcium atoms in so far as the radioisotope is concerned. 相似文献
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Deschamps P Durand N Bard E Hamelin B Camoin G Thomas AL Henderson GM Okuno J Yokoyama Y 《Nature》2012,483(7391):559-564
Past sea-level records provide invaluable information about the response of ice sheets to climate forcing. Some such records suggest that the last deglaciation was punctuated by a dramatic period of sea-level rise, of about 20?metres, in less than 500?years. Controversy about the amplitude and timing of this meltwater pulse (MWP-1A) has, however, led to uncertainty about the source of the melt water and its temporal and causal relationships with the abrupt climate changes of the deglaciation. Here we show that MWP-1A started no earlier than 14,650 years ago and ended before 14,310 years ago, making it coeval with the B?lling warming. Our results, based on corals drilled offshore from Tahiti during Integrated Ocean Drilling Project Expedition 310, reveal that the increase in sea level at Tahiti was between 12 and 22 metres, with a most probable value between 14 and 18 metres, establishing a significant meltwater contribution from the Southern Hemisphere. This implies that the rate of eustatic sea-level rise exceeded 40 millimetres per year during MWP-1A. 相似文献
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Fractionation of total RNA prepared from intersterile wild type strains of Ascobolus immersus revealed the existence of differences at the 4S and 5S levels which may be related to the polymorphism of these species or sub-species, bearing the same name and coasting along in nature. 相似文献