{ diff(x1, t) = 0,
  diff(x2, t) = (1*k7*k50 + 1*k8/(1 + (x2/k9)^k10) + (-1)*k15*x2*x5 + (-1)*k16*x2*x5 + 1*k18/(1 + (k19/x7)^k20))/k2,
  diff(x3, t) = 0,
  diff(x4, t) = ((-1)*k11*x4 + 1*k12*x5 + 1*k14*x7/x4)/k3,
  diff(x5, t) = (1*k11*x4 + (-1)*k12*x5 + (-1)*k13*x5)/k2,
  diff(x6, t) = 1*k13*x5/k6,
  diff(x7, t) = ((-1)*k14*x7/x4 + 1*k15*x2*x5 + (-1)*k18/(1 + (k19/x7)^k20) + 1*k21/(1 + (x7/k22)^k23) + (-1)*k24*x14*x7 + 1*k25*x15*x13 + (-1)*k27*x7 + 1*k30*x17 + 1*k32*x21 + 1*k34*x23*x18 + 1*k35*x23 + 1*k49*x30*x34)/k3,
  diff(x8, t) = 1*k16*x2*x5/k6,
  diff(x9, t) = 0,
  diff(x10, t) = (1*k17*x11 + 1*k26*x11 + (-1)*k43*x11*x10*x31)/k5,
  diff(x11, t) = (1*k36*x25*x23 + 1*k37*x23 + (-1)*k40*x14*x11 + 1*k41*x15*x28 + (-1)*k42*x11 + (-1)*k43*x11*x10*x31 + 1*k44/(1 + (x11/k45)^k46))/k4,
  diff(x12, t) = 0,
  diff(x13, t) = (1*k24*x14*x7 + (-1)*k25*x15*x13)/k3,
  diff(x14, t) = 0/k3,
  diff(x15, t) = 0/k3,
  diff(x16, t) = 0,
  diff(x17, t) = (1*k27*x7 + (-1)*k30*x17 + (-1)*k31*x17*x22 + 1*k47*x30*x33)/k5,
  diff(x18, t) = (1*k28*k55/x7 + (-1)*k29*x18)/k3,
  diff(x19, t) = 0,
  diff(x20, t) = 1*k29*x18/k3,
  diff(x21, t) = (1*k31*x17*x22 + (-1)*k32*x21 + (-1)*k33*x21*x24)/k5,
  diff(x22, t) = 0/k5,
  diff(x23, t) = (1*k33*x21*x24 + (-1)*k34*x23*x18 + (-1)*k35*x23 + (-1)*k36*x25*x23 + (-1)*k37*x23 + 1*k48*x30*x33)/k5,
  diff(x24, t) = 0/k5,
  diff(x25, t) = (1*k38*k56/x11 + (-1)*k39*x25)/k4,
  diff(x26, t) = 0,
  diff(x27, t) = 1*k39*x25/k4,
  diff(x28, t) = (1*k40*x14*x11 + (-1)*k41*x15*x28)/k4,
  diff(x29, t) = 1*k42*x11/k4,
  diff(x30, t) = (1*k43*x11*x10*x31 + (-1)*k47*x30*x33 + (-1)*k48*x30*x33 + (-1)*k49*x30*x34)/k5,
  diff(x31, t) = 0/k5,
  diff(x32, t) = 0,
  diff(x33, t) = 0/k5,
  diff(x34, t) = 0/k3 }