Figure 7. Illustration of mean channel 6 clot ratio (percent of maximal) values at four platelet activating factor (PAF) concentrations (1.25, 6.25, 12.5, and 150 nM, channels 3-6, respectively) before and after administration of desmopressin acetate (0.3-0.4 micro gram/kg) in a series of patients with excessive perioperative bleeding (n = 25); (closed circle) represents mean clot ratio values with standard deviation (T-bars) before administration of platelets, whereas (closed triangle) represents mean clot ratio values with standard deviation (T-bars) after administration of platelets in the perioperative period. Mean clot ratio values were statistically greater (P < 0.01) at all PAF concentrations.