1Department of Occupational and Environmental Medicine, College of Medicine, Dong-A University, Korea. gyjung@daunet.donga.ac.kr
2Department of Occupational and Environmental Medicine, College of Medicine, Pusan Paik Hospital, In-Je University, Korea.
3Masan Samsung Hospital, Korea.
4Koshin Hospital, Korea.
5University of Ulsan, Korea. JFIF d d Ducky d qhttp://ns.adobe.com/xap/1.0/