Submitted on: 20 November 2009.
Revised on: 10 December 2009.
Accepted on: 20 January 2010.
___________________COPD-Journal of Chronic Obstructive Pulmonary Disease
http://reply.papertrans.cn/1/66/6505/6505-32.png
Submitted on: 02 April 2016.
Revised on: 12 June 2016.
Accepted on: 02 August 2016.
___________________COPD-Journal of Chronic Obstructive Pulmonary Disease
Submitted on: 19 May 2013.
Revised on: 02 August 2013.
Accepted on: 08 September 2013.
___________________COPD-Journal of Chronic Obstructive Pulmonary Disease
http://reply.papertrans.cn/1/66/6505/6505-35.png
Submitted on: 07 January 2016.
Revised on: 09 April 2016.
Accepted on: 26 May 2016.
___________________COPD-Journal of Chronic Obstructive Pulmonary Disease