1Zhong N,Wang C,Yao W. Prevalence of chronic obstructive pulmonary discas(c) in China:a large,population-based survey[J].American Journal of Respiratory and Critical Care Medicine,2007,(8):753-760.doi:10.1164/rccm.200612-1749OC.
2GOLD Executive Committee. Global strategy for the diagnosis,management,and prevention of chronic obstructive pulmonary disease (Revised 2011)[OL].http://www.goldcopd.com,2012.
3Hogg JC,Chu F,Utokaparch S. The nature of small-airway obstruction in chronic obstructive pulmonary disease[J].New England Journal of Medicine,2004.2645-2653.doi:10.1056/NEJMoa032158.
4Ley-Zaporozhan J,Kauczor HU. Imaging of airways:chronic obstructive puhmonary disease[J].Radiologic Clinics of North America,2009,(2):331-342.doi:10.1016/j.rcl.2008.11.012.
5Fain SB,Panth SR,Evans MD. Early emphysematous changes in asymptomatic smokers:detection with 3He MR imaging[J].Radiology,2006.875-883.doi:10.1148/radiol.2393050111.
6Swanney MP,Ruppel G,Enright PL. Using the lower limit of normal for the FEVI/FVC ratio reduces the misclassification of airway obstruction[J].Thorax,2008.1046-1051.doi:10.1136/thx.2008.098483.
7Stanojevic S,Wade A,Stocks J. Reference ranges for spiromctry across all ages:a new approach[J].American Journal of Respiratory and Critical Care Medicine,2008.253-260.
8Enright P,Brusasco V. Counterpoint:should we abandon FEV1/FVC 《 0.70 to detect airway obstruction[J].Yes Chest,2010.1040-1042.
9Mohamed Hoesein FA,Zanen P,Lammers JW. Lower limit of normal or FEVI/FVC 《 0.70 in diagnosing COPD:an evidencebased review[J].Respiratory Medicine,2011.907-915.
10Agusti A,Calverley PM,Celli B. Characterisation of COPD heterogeneity in the ECLIPSE cohort[J].Respiratory Research,2010.122.