Urea nitrogen^post dialysis/pre dialysis:MRto:Pt:Dial fld prt:Qn
urea nitrogen^post dialysis/pre dialysis:mrto:pt:dial fld prt:qn
Urea nitrogen post dialysis/pre dialysis (Perit dial fld) [Mass ratio]
urea nitrogen post dialysis/pre dialysis (perit dial fld) [mass ratio]