title: A test of time invariance in models of ferrokinetics.
abstract: Application of a particular mathematical property of time-invariant systems to experimental data obtained from injection and infusion of radioactive tracer iron in normal subjects is used to show that the generally applied assumption of time invariance to ferrokinetic systems is unjustified and may lead to substantial errors in analysis.
mesh_terms: D000328:Adult; D004920:Erythropoiesis; D006801:Humans; D007501:Iron / Q000097:blood / Q000378:metabolism*; D007504:Iron Radioisotopes; D007700:Kinetics; D008297:Male; D008433:Mathematics; D008954:Models, Biological
chemical_list: D007504:Iron Radioisotopes; D007501:Iron