Category B - full version without watermark 1024x576 (check terms and conditions at www.teledesign.de) The embed version with watermark is free of charge. - Description: So called blood thinners lead to an increased bleeding tendency. Aspirin for instance restrains platelets from clumping -- while this helps to prevent thrombosis it also leads to delayed wound closure. Marcumar has also an anticoagulatory effect. It inhibits the coagulation factors that are necessary to stabilize clotting of the platelets.