[ Eq(Derivative(x1, t), 0),
  Eq(Derivative(x2, t), ((-1)*k1*x2/(k2 + x2) + (-1)*k6*x2/(k7 + x2) + (-1)*k8*x2/(k9 + x2))/k10),
  Eq(Derivative(x3, t), (1*k1*x2/(k2 + x2) + (-1)*k3*x3*x4*k10*k10)/k10),
  Eq(Derivative(x4, t), ((-1)*k3*x3*x4*k10*k10 + 1*k4*(k5 - x4)*k10)/k10),
  Eq(Derivative(x5, t), 1*k3*x3*x4*k10*k10/k10),
  Eq(Derivative(x6, t), 1*k6*x2/(k7 + x2)/k10),
  Eq(Derivative(x7, t), 1*k8*x2/(k9 + x2)/k10) ]