Yang Shuanying, Bu Lina
Department of Respiratory Medicine, the Second Hosipital Affiliated to Xi'an Jiaotong University College of Medicine, Xi'an 710004, China.
Zhongguo Fei Ai Za Zhi. 2010 May;13(5):393-5. doi: 10.3779/j.issn.1009-3419.2010.05.02.