{ diff(x1, t) = (1*k8*(k62*k31*(k55*x7 - k54*x1/k41)/(k32*k33)/((1 + k55/k32 + k54/k34)*(1 + x7/k33 + x1/k35)) + k58*k36*(k55*x7 - k54*x1/k41)/(k37*k38)/((1 + k55/k37 + k54/k39)*(1 + x7/k38 + x1/k40))) + (-1)*k8*k63*k42*(x8*x1 - k55*k54/k43)/(k2*k3)/((1 + x8/k2 + k55/k5)*(1 + x1/k3 + k54/k6 + x5/k4 + x7/k7)) + (-1)*k8*k52*x1)/k8,
  diff(x2, t) = ((-1)*k8*k61*k28*x2/k29/(1 + x2/k29 + x4/k30) + 1*k8*k64*k46*x10*x9/(k47*k48)/((1 + x10/k47 + x2/k49)*(1 + x9/k48 + x3/k50)))/k8,
  diff(x3, t) = (1*k8*(k56*k9*x4*x9/(k10*k11)/((1 + x4/k10 + x6/k12)*(1 + x9/k11 + x3/k13)) + k57*k14*x4*x9/((1 + x4/k15 + x6/k17)*(1 + x9/k16 + x3/k18))) + 1*k8*k64*k46*x10*x9/(k47*k48)/((1 + x10/k47 + x2/k49)*(1 + x9/k48 + x3/k50)) + (-1)*k8*k51*x3)/k8,
  diff(x4, t) = ((-1)*k8*(k56*k9*x4*x9/(k10*k11)/((1 + x4/k10 + x6/k12)*(1 + x9/k11 + x3/k13)) + k57*k14*x4*x9/((1 + x4/k15 + x6/k17)*(1 + x9/k16 + x3/k18))) + 1*k8*k61*k28*x2/k29/(1 + x2/k29 + x4/k30))/k8,
  diff(x5, t) = (1*k8*k59*k19*(x6 - x5/k23)/k20/(1 + x6/k20 + x5/k21) + (-1)*k8*k63*k44*(x8*x5 - k55*x7/k45)/(k2*k4)/((1 + x8/k2 + k55/k5)*(1 + x1/k3 + k54/k6 + x5/k4 + x7/k7)) + (-1)*k8*k53*x5)/k8,
  diff(x6, t) = (1*k8*(k56*k9*x4*x9/(k10*k11)/((1 + x4/k10 + x6/k12)*(1 + x9/k11 + x3/k13)) + k57*k14*x4*x9/((1 + x4/k15 + x6/k17)*(1 + x9/k16 + x3/k18))) + (-1)*k8*k59*k19*(x6 - x5/k23)/k20/(1 + x6/k20 + x5/k21) + (-1)*k8*k60*k24*(x6 - x8/k27)/k25/(1 + x6/k25 + x8/k26))/k8,
  diff(x7, t) = ((-1)*k8*(k62*k31*(k55*x7 - k54*x1/k41)/(k32*k33)/((1 + k55/k32 + k54/k34)*(1 + x7/k33 + x1/k35)) + k58*k36*(k55*x7 - k54*x1/k41)/(k37*k38)/((1 + k55/k37 + k54/k39)*(1 + x7/k38 + x1/k40))) + 1*k8*k63*k44*(x8*x5 - k55*x7/k45)/(k2*k4)/((1 + x8/k2 + k55/k5)*(1 + x1/k3 + k54/k6 + x5/k4 + x7/k7)))/k8,
  diff(x8, t) = (1*k8*k60*k24*(x6 - x8/k27)/k25/(1 + x6/k25 + x8/k26) + (-1)*k8*k63*k42*(x8*x1 - k55*k54/k43)/(k2*k3)/((1 + x8/k2 + k55/k5)*(1 + x1/k3 + k54/k6 + x5/k4 + x7/k7)) + (-1)*k8*k63*k44*(x8*x5 - k55*x7/k45)/(k2*k4)/((1 + x8/k2 + k55/k5)*(1 + x1/k3 + k54/k6 + x5/k4 + x7/k7)))/k8,
  diff(x11, t) = 0,
  diff(x12, t) = 0,
  diff(x13, t) = 0,
  diff(x14, t) = 0,
  diff(x15, t) = 0,
  diff(x16, t) = 0,
  diff(x17, t) = 0,
  diff(x18, t) = 0,
  diff(x19, t) = 0,
  diff(x20, t) = 0,
  diff(x21, t) = 0 }