[1] Univ Tsukuba, Mito Kyodo Gen Hosp, Mito Med Ctr, Div Resp Med, Mito, Ibaraki, Japan
[2] Mito Med Ctr, Div Resp Med, Mito, Ibaraki, Japan
[3] Mito Med Ctr, Div Thorac Surg, Mito, Ibaraki, Japan
[4] Hitachi Gen Hosp, Div Resp Med, Hitachi, Ibaraki, Japan
[5] Hitachi Gen Hosp, Div Thorac Surg, Hitachi, Ibaraki, Japan
[6] Ibarakihigashi Hosp, Div Resp Med, Tokai, Ibaraki, Japan
[7] Univ Tsukuba, Div Resp Med, Hitachinaka Med Ctr, Mito, Ibaraki, Japan
[8] Ibaraki Cent Hosp, Resp Ctr, Kasama, Ibaraki, Japan
[9] Tsuchiura Kyodo Gen Hosp, Div Resp Med, Tsuchiura, Ibaraki, Japan
[10] Tsuchiura Kyodo Gen Hosp, Div Thorac Surg, Tsuchiura, Ibaraki, Japan
[11] Univ Tsukuba, Fac Clin Med, Tsukuba, Ibaraki, Japan
[12] Tsukuba Med Ctr Hosp, Div Resp Med, Tsukuba, Ibaraki, Japan
[13] Tsukuba Med Ctr Hosp, Div Thorac Surg, Tsukuba, Ibaraki, Japan
[14] Tsukuba Kinen Hosp, Div Thorac Surg, Tsukuba, Ibaraki, Japan
[15] Kasumigaura Med Ctr, Div Resp Med, Tsuchiura, Ibaraki, Japan
[16] Tokyo Med Univ, Ibaraki Med Ctr, Div Resp Med, Ami, Ibaraki, Japan
[17] Tokyo Med Univ, Ibaraki Med Ctr, Div Thorac Surg, Ami, Ibaraki, Japan
[18] Ryugasaki Saiseikai Hosp, Div Resp Med, Ryugasaki, Japan
[19] JA Toride Med Ctr, Div Resp Med, Toride, Japan
[20] Seinan Med Ctr, Div Resp Med, Sakai, Osaka, Japan
[21] Tsukuba Gakuen Gen Hosp, Div Resp Med, Tsukuba, Ibaraki, Japan