[ Diff(x[1], t) = (1*k[11]*k[1]/(1 + k[3]*(x[1] + x[2] + x[3]))*(x[1] + x[2] + k[7])/(x[1] + x[2] + k[7] + k[8]*x[3])*x[1] + (-1)*k[11]*k[5]*x[1])/k[11],
  Diff(x[2], t) = (1*k[11]*k[2]/(1 + k[4]*(x[1] + x[2] + x[3]))*(x[1] + x[2] + k[7])/(x[1] + x[2] + k[7] + k[9]*x[3])*x[2] + (-1)*k[11]*k[6]*x[2])/k[11],
  Diff(x[3], t) = (1*k[11]*k[1]/(1 + k[3]*(x[1] + x[2] + x[3]))*(1 - k[10]*(x[1] + x[2])/(x[3] + k[7] + k[10]*(x[1] + x[2])))*x[3] + (-1)*k[11]*k[5]*x[3])/k[11] ]