1. Clinical Surgical Research Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
2. Division of Gastrointestinal Surgery and Endoscopy, Department of Surgery, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
3. Division of Pediatrics Surgery, Department of Surgery, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
4. Department of Biochemistry, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
5. Department of Obstetrics and Gynecology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand