1. Clinical Labororatory, The First Affiliated Hospital of Harbin Medical University, Harbin 150081, China
2. Department of Ophtalmology, The Second Affiliated Hospital of Harbin Medical University, Harbin 150081, China
3. Public Health School, Mudanjiang Medical College, Mudanjiang 157011, China
4. Department of Ophtalmology, Eye Hospital of Heilongjiang Province and the First Affiliated Hospital of Harbin Medical University, Harbin 150081, China
5. Department of Nutrition and Food Hygiene, Public Health School of Harbin Medical University, Harbin 150081, China