1Cuidelines for the management of mild hypertension Memorandum from a world health organization/international society of hypertension meeting guidelines subcommittee of the WHO/ISH mild hypertension liaison committee.Hypertension,1993,22(3):392~403.
2Tsuji H,Venditti FJ Jr,Manders ES,et al.Reduced heart rate variabhity and moerality risk in an elderly cohoet.The Framingham heart study.Circulation,1994,90(2):878~883.