“Platelet aggregation … by arachidonic acid (0.4 to 0.8 mM) was … significantly less than in matched controls by imidazole , a thromboxane synthetase inhibitor (p < 0.01, n = 11), and 13-azaprostanoic acid, an antagonist of the actions of PGH2 or TXA2 on platelets (p < 0.04, n = 14).”