1. Department of Oral Medicine and Center for Salivary Gland Diseases of Peking University School and Hospital of Stomatology, Beijing, P.R. China
2. Department of Physiology and Pathophysiology, Peking University Health Science Center, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, and Beijing Key Laboratory of Cardiovascular Receptors Research, Beijing, P.R. China
3. Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, P.R. China
4. Department of Dentistry, Santa Cecília University, Santos, Brazil