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Inherited susceptibility to lung cancer may be associated with the T790M drug resistance mutation in EGFR 总被引:9,自引:0,他引:9
Bell DW Gore I Okimoto RA Godin-Heymann N Sordella R Mulloy R Sharma SV Brannigan BW Mohapatra G Settleman J Haber DA 《Nature genetics》2005,37(12):1315-1316
Somatic activating mutations in EGFR identify a subset of non-small cell lung cancer that respond to tyrosine kinase inhibitors. Acquisition of drug resistance is linked to a specific secondary somatic mutation, EGFR T790M. Here we describe a family with multiple cases of non-small cell lung cancer associated with germline transmission of this mutation. Four of six tumors analyzed showed a secondary somatic activating EGFR mutation, arising in cis with the germline EGFR mutation T790M. These observations implicate altered EGFR signaling in genetic susceptibility to lung cancer. 相似文献
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Klironomos JN Allen MF Rillig MC Piotrowski J Makvandi-Nejad S Wolfe BE Powell JR 《Nature》2005,433(7026):621-624
Attempts to understand the ecological effect of increasing atmospheric CO2 concentration, [CO2], usually involve exposing today's ecosystems to expected future [CO2] levels. However, a major assumption of these approaches has not been tested--that exposing ecosystems to a single-step increase in [CO2] will yield similar responses to those of a gradual increase over several decades. We tested this assumption on a mycorrhizal fungal community over a period of six years. [CO2] was either increased abruptly, as is typical of most [CO2] experiments, or more gradually over 21 generations. The two approaches resulted in different structural and functional community responses to increased [CO2]. Some fungi were sensitive to the carbon pulse of the abrupt [CO2] treatment. This resulted in an immediate decline in fungal species richness and a significant change in mycorrhizal functioning. The magnitude of changes in fungal diversity and functioning in response to gradually increasing [CO2] was smaller, and not significantly different to those with ambient [CO2]. Our results suggest that studies may overestimate some community responses to increasing [CO2] because biota may be sensitive to ecosystem changes that occur as a result of abrupt increases. 相似文献
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Jeff Dooley 《Systemic Practice and Action Research》1993,6(4):359-381
An examination of Piaget's conception of the source, nature, development, and use of knowledge reveals that his model for the genetic development of human knowledge is cybernetic and self-organizing. Moreover, Piaget presents a model of cognition which is a reflection and extension of autopoietic biological organization; both cognitive and organic systems are seen to exhibit organizational closure and structural plasticity. An action-based intervention method, modeling embedded learning structures as cybernetic, autopoietic systems, may provide insight toward clarifying some theoretical and methodological problems of critical systems thinking. 相似文献
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