thrombin blood-clotting enzyme. 3d .

thrombin alpha coagulation factor blood activated prothrombin plasma cascade thrombus clot fibrin clotting vitamin antithrombin inhibitor direct anticoagulant thinner hirudin argatroban melagatran ximelagatran dabigatran structure peptide protein amino acid molecule polypeptide polymer atoms science scientific disease health molecular model 3d illustration