<unk>  <unk>  is a measure used in<unk>  physiology to calculate<unk><unk> <unk>  (RPF) and hence estimate<unk>  function. The<unk>  can be calculated with : where extraction ratio is the ratio of compound entering the kidney that is excreted into the final urine. When using a compound with an extraction ratio near 1, such as para-aminohippurate (PAH),<unk>  approximates RPF. Therefore, PAH clearance can be used to estimate RPF.
Effective renal plasma flow
Effective circulating volume
Renal threshold
Renal blood flow
Glomerular filtration rate
Free water clearance
Critical closing pressure
Renal sodium reabsorption