1. Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul, Korea.
2. Division of Endocrinology and Metabolism, Department of Internal Medicine, Yantai Affiliated Hospital of Binzhou Medical University, Yantai, China.
3. Division of Endocrinology and Endocrine Research Institute, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
4. Division of Endocrinology and Metabolism, Department of Internal Medicine, Dongguk University Ilsan Hospital, Dongguk University College of Medicine, Goyang, Korea.
5. Division of Endocrinology and Metabolism, Department of Internal Medicine, Ajou University School of Medicine, Suwon, Korea.