[ Eq(Derivative(x1, t), (1*k42*7/8*x1*(k1 + x3/(k3 + k4*x3))*(1 - x1/k5)*(x1/(k6/(1 + k7*x7)) - 1) + (-1)*k42*k8*(1 + k9*x4)*x1 + (-1)*k42*(k10 + k11*x4 + k12*x8)*x1)/k42),
  Eq(Derivative(x2, t), (1*k42*(k10 + k11*x4 + k12*x8)*x1 + 1*k42*k2*x2 + (-1)*k42*k8*x2)/k42),
  Eq(Derivative(x3, t), (1*k42*k13*x1 + (-1)*k42*k14*x3 + (-1)*k42*(k15*x1 + k16*(x5 + x6))*x3)/k42),
  Eq(Derivative(x4, t), (1*k42*k17*x1 + (-1)*k42*k18*x4 + (-1)*k42*(k19*x1 + k20*(x5 + x6))*x4)/k42),
  Eq(Derivative(x5, t), (1*k42*k21*(1 - x5/k22)*x5 + 1*k42*x3*x5/(k23 + k24*x3) + 1*k42*x4*x5/(k25 + k26*x4))/k42),
  Eq(Derivative(x6, t), (1*k42*k27*(1 - x6/k28)*x6 + 1*k42*x3*x6/(k29 + k30*x3) + 1*k42*x4*x6/(k31 + k32*x4))/k42),
  Eq(Derivative(x7, t), (1*k42*k33 + 1*k42*k34*x5 + (-1)*k42*k35*x7 + (-1)*k42*k36*x1*x7)/k42),
  Eq(Derivative(x8, t), (1*k42*k37 + 1*k42*k38*x6 + (-1)*k42*k39*x8 + (-1)*k42*k40*x1*x8)/k42) ]