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Engelen MP, Orozco-Levi M, Deutz NE, Barreiro E, Hernández N, Wouters EF, Gea J, Schols AM.Engelen MP, et al.Eur Respir J. 2004 Apr;23(4):545-51. doi: 10.1183/09031936.04.00022204.Eur Respir J. 2004.PMID: 15083752Free article.