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994-1002; discussion 1003-4(November 2007)4950<m:linebreak></m:linebreak>GR: R01-HL080644/HL/NHLBI NIH HHS/United States; GR: R37-AI032475/AI/NIAID NIH HHS/United States; JID: 7910653; CON: Am J Epidemiol. 2007 Nov 1;166(9):985-93. PMID: 17875580; 2007/09/17 aheadofprint; ppublish;.