Dose-Response Relationship, DrugRitonavirTime FactorsLopinavirHIV Protease InhibitorsPyrimidinonesSaquinavirIndinavirAnti-HIV AgentsDrug InteractionsArea Under CurveHIV InfectionsCarbamatesNelfinavirDrug Therapy, CombinationDose-Response Relationship, RadiationSulfonamidesOxytropisBenzoxazinesCytochrome P-450 CYP3APyridines