the following results were obtained : ( a ) the rate constant ( k1 ) for uptake of 125i-insulin by liver plasma membranes was 2 x 10 ( 6 ) m-1 s-1 and invariant at applied hormone concentrations of 7.5 to 100 x 10 ( -11 ) m .
C1721009
k1
C0007603
plasma membranes