dx1/dt = -b*x1*x5*x2*q - b*x1*x5*x7 - b*x1*x5*x6; dx2/dt = -x3*k*r + x3*k - x2*g1; dx3/dt = b*x1*x5*x2*q + b*x1*x5*x7 + b*x1*x5*x6 - x3*k; dx4/dt = alpha*x7; dx5/dt = 0; dx6/dt = alpha*x7 - g2*x6; dx7/dt = -alpha*x7 + x3*k*r - g1*x7; y1 = x5; y2 = x4