{ diff(x1, t) = (1*k29*k2*(x7 + k3)/(k4*(1 + (x3/k5)^k6) + x7 + k3) + (-1)*k29*k12*x1)/k29,
  diff(x2, t) = (1*k29*k13*x1^k14 + (-1)*k29*k15*x2 + (-1)*k29*k16*x2 + 1*k28*k17*x3)/k29,
  diff(x3, t) = (1*k29*k16*x2 + (-1)*k28*k17*x3 + (-1)*k28*k18*x3)/k28,
  diff(x4, t) = (1*k29*k8*x3^k9/(k10^k9 + x3^k9) + (-1)*k29*k19*x4)/k29,
  diff(x5, t) = (1*k29*k20*x4 + (-1)*k29*k21*x5 + (-1)*k29*k22*x5 + 1*k28*k23*x6)/k29,
  diff(x6, t) = (1*k29*k22*x5 + (-1)*k28*k23*x6 + (-1)*k28*k24*x6 + (-1)*k28*k25*x6 + 1*k28*k26*x7)/k28,
  diff(x7, t) = (1*k28*k25*x6 + (-1)*k28*k26*x7 + (-1)*k28*k27*x7)/k28 }