1. Department of Respiration, Hengdian Wenrong's Hospital, Dongyang, Zhejiang 322118, P.R. China
2. Department of Urology, Dong Yang Red Cross Hospital, Jinhua, Zhejiang 322100, P.R. China
3. Department of Respiration, Dongyang People's Hospital, Jinhua, Zhejiang 322100, P.R. China
4. Cor Pulmonale Research Laboratory, Wenzhou Medical University, Wenzhou, Zhejiang 325035, P.R. China