Urinary levels of Isoprostane-F2_-III (upper panel) and Isoprostane-F_2-VI (middle panel) and plasma prothrombin fragment F1+2 (lower panel) in patients positive for antiphospholipid antibodies (aPL+), in patients with systemic lupus erythematosus negative for the antiphospholipid antibodies (SLE aPL−), and in healthy subjects (HS). Statistical analysis was performed by Mann-Whitney-U test.