80.承上題,其給藥速率R(mg/h)與穩定狀態血中濃度Css(mg/L)間之關係如下圖。則此藥在體內之最大排除速率(Vmax)對Michaelis-Menten常數(KM)之比值(即Vmax/KM)為何?

(A)0.66
(B)1
(C)1.5
(D)2

(A)0.66
(B)1
(C)1.5
(D)2
答案:登入後查看
統計: A(981), B(539), C(4581), D(415), E(0) #1837578
統計: A(981), B(539), C(4581), D(415), E(0) #1837578
詳解 (共 3 筆)
#2936547
Michaelis-Menten kinetics
R = Vmax x Css/(Km + Css)
兩邊倒數後可得
1/R = (Km/Vmax) x (1/Css) + (1/Vmax)
Vmax/Km即為圖形直線之斜率倒數
取任2點(-0.13,0)、(-0.05,0.05)求斜率倒數
Vmax/Km = [-0.05-(-0.013)]/(0.05-0)
= 1.6
選(C)
88
2