1 Division of Respiratory Diseases, Department of Internal Medicine, Jikei University School of Medicine, 3-19-18 Nishishimbashi, Minatoku, Tokyo, Japan. Electronic address: hirohara@jikei.ac.jp.
2 Division of Respiratory Diseases, Department of Internal Medicine, Jikei University School of Medicine, 3-19-18 Nishishimbashi, Minatoku, Tokyo, Japan.
3 Department of Surgery, Jikei University School of Medicine, Japan.