Piperazines/pharmacology; Piperidines/pharmacology; Platelet Glycoprotein GPIIb-IIIa Complex/antagonists & inhibitors; Adenosine Diphosphate/pharmacology; Adenosine Triphosphate/metabolism; Animals; Benzamidines/pharmacology; Biotinylation; Bleeding Time; Blood Platelets/drug effects; Blood Platelets/metabolism; Collagen/metabolism; Cricetinae; Dogs; Dose-Response Relationship, Drug; Fibrinogen/metabolism; Fibrinolytic Agents/pharmacology; Guinea Pigs; Haplorhini; Humans; Mice; Microspheres; Oligopeptides/pharmacology; Piperazines/chemistry; Piperidines/chemistry; Platelet Adhesiveness/drug effects; Platelet Aggregation/drug effects; Platelet Aggregation Inhibitors/pharmacology; Platelet Glycoprotein GPIIb-IIIa Complex/metabolism; Protein Binding/drug effects; Rabbits; Rats; Stress, Mechanical