In the first, they studied the blood-forming stem cells of mice manufactured to have single mutations that produce them especially prone to accumulating additional genetic mistakes. In each of the three various kinds of mutant mice they studied, the stem cells seemed to behave normally also to produce new bloodstream cells. However, the entire truth came out when they had taken blood-forming stem cells from the three types of mice and utilized those cells to repopulate the bone marrow of irradiated mice.Attempts to reduce the risk of bleeding by reducing the strength of warfarin therapy have resulted in decreased efficacy without much less bleeding.4,5 If warfarin is discontinued, the chance of recurrent venous thromboembolism is 6 to 10 percent per year in patients without reversible risk elements.6-9 Furthermore, such patients are at increased risk for arterial thrombotic events, such as for example myocardial infarction, stroke, and vascular death,1,10,11 and the rate of the events can also be reduced with anticoagulation therapy.12 Apixaban can be an oral factor Xa inhibitor that is administered in fixed dosages without the need for laboratory monitoring.