CreatinineMethylhistidinesBody WeightCreatinePeritoneal Dialysis, Continuous AmbulatoryGlomerular Filtration RateKidneyNitrogenBody HeightBody CompositionAnthropometryReference ValuesSodiumPotassiumAgingBody Mass IndexKidney Function TestsKidney DiseasesProteinuriaAcute Kidney InjuryBlood Urea NitrogenBiological MarkersCystatin CRenal InsufficiencyUreaKidney Failure, ChronicNatriuresisDiuresisFecesBileTime FactorsUrineUrinalysisMetabolic Clearance RateKidney TubulesBlood PressureKidney TransplantationDiabetic NephropathiesUric AcidCystatinsElectrolytesProspective StudiesInulinHypertensionAlbuminuriaHippuratesRenal CirculationRisk FactorsNephrectomyDietAdministration, OralChromatography, High Pressure LiquidRetrospective StudiesDiureticsRenal Insufficiency, ChronicKidney GlomerulusFurosemideTreatment OutcomeIntestinal Absorption