AspirinPlatelet Aggregation InhibitorsAnti-Inflammatory Agents, Non-SteroidalDrug Therapy, CombinationTiclopidineDrug Administration ScheduleThromboxane B2Cyclooxygenase InhibitorsTreatment OutcomePlatelet AggregationSalicylatesPlatelet Function TestsDouble-Blind MethodTime FactorsAdministration, Oral