2Benotti J R, Dalen J E. The natural history of pulmonary embolism[J]. Clin Chest Med.1984,5(3) ,405-407.
3Guidelines on diagnosis and management of acute pulmonary embolism task forle on pulmonary embolism, eruopean society cardiology[J]. Eur Heart J, 2000,21(16) : 1301-1306.