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Johnson PR, Burgess JK, Ge Q, Poniris M, Boustany S, Twigg SM, Black JL.Johnson PR, et al. Among authors: twigg sm.Am J Respir Crit Care Med. 2006 Jan 1;173(1):32-41. doi: 10.1164/rccm.200406-703OC. Epub 2005 Sep 22.Am J Respir Crit Care Med. 2006.PMID: 16179645