AspirinPlatelet Aggregation InhibitorsAnti-Inflammatory Agents, Non-SteroidalPlatelet Function TestsTiclopidinePlatelet AggregationThromboxane B2Desensitization, ImmunologicFibrinolytic AgentsDrug Therapy, CombinationWarfarinDose-Response Relationship, DrugThrombosisAnticoagulantsBlood PlateletsTime FactorsDrug Administration ScheduleTreatment OutcomeDouble-Blind MethodRisk FactorsProspective StudiesStrokeCyclooxygenase InhibitorsSalicylatesRisk AssessmentFollow-Up StudiesCardiovascular DiseasesCoronary DiseaseArrestins