Fiber diameters determined by SEM. Each bar denotes the mean fiber width (in nanometers) and its standard deviation for PRP and PPP plasma clots aged 3 hours and then treated as follows (30-minute permeation period with each effector): HBS (pH 7.4); Arg, argatroban (100 μmol/L); SK, streptokinase (250 IU/mL); Alt, alteplase (10 μg/mL); SK/Arg (250 IU/mL streptokinase, then 100 μmol/L argatroban); Alt/Arg (10 μg/mL alteplase, then 100 μmol/L argatroban). Measurements were made on 20 to 50 randomly selected fibrin strands, as visualized in high-magnification micrographs such as those presented in Fig 3B.