A greater knowledge of the basic molecular mechanisms which regulate platelet function, coagulation, the fibrinolytic system and their interaction with the vessel wall has allowed a better understanding of the numerous aspects involved in the pathogenesis of thrombosis and the regulation of hemostasis. Thrombosis represents today one of the causes of death in the Western hemisphere. Arterial thrombosis may lead to myocardial infarction, cerebral and peripheral vascular diseases. Venous thrombosis, on the other hand, is a complication of heart disease, surgery, extensive trauma, several...