Lazar 1997 model

\begin{align*}
  \frac{d y1}{dt} &= k10 \cdot y3 + y1 \cdot (- k1 - k17) + k16 \cdot y11 \cdot y9 \\ 
  \frac{d y2}{dt} &= k1 \cdot y1 + k11 \cdot y4 + k7 \cdot y3 - y2 \cdot (k23 + k6) + k22 \cdot y12 \cdot y9 \\ 
  \frac{d y3}{dt} &= k6 \cdot y2 - y3 \cdot (k10 + k2 + k7) \\ 
  \frac{d y4}{dt} &= k2 \cdot y3 + k9 \cdot y5 - y4 \cdot (k11 + k8) \\ 
  \frac{d y5}{dt} &= k13 \cdot y7 + k8 \cdot y4 - y5 \cdot (k12 + k3 + k9) \\ 
  \frac{d y6}{dt} &= k19 \cdot y8 + k3 \cdot y5 - k18 \cdot y6 \\ 
  \frac{d y7}{dt} &= k12 \cdot y5 - y7 \cdot (k13 + k14 + k4) + k15 \cdot y10 \cdot y11 \\ 
  \frac{d y8}{dt} &= k18 \cdot y6 + k4 \cdot y7 - y8 \cdot (k19 + k20) + k21 \cdot y10 \cdot y12 \\ 
  \frac{d y9}{dt} &= k17 \cdot y1 + k23 \cdot y2 + k24 \cdot y10 - y9 \cdot (k25 + k16 \cdot y11 + k22 \cdot y12) \\ 
  \frac{d y10}{dt} &= k14 \cdot y7 + k20 \cdot y8 + k25 \cdot y9 - y10 \cdot (k24 + k15 \cdot y11 + k21 \cdot y12) \\ 
  \frac{d y11}{dt} &= k14 \cdot y7 + k17 \cdot y1 - y11 \cdot (k15 \cdot y10 + k16 \cdot y9) \\ 
  \frac{d y12}{dt} &= k20 \cdot y8 + k23 \cdot y2 - y12 \cdot (k21 \cdot y10 + k22 \cdot y9) \\ 
  \frac{d y13}{dt} &= - k6n \cdot y13 \\ 
  \frac{d y14}{dt} &= k6n \cdot y13 \\ 
  \frac{d y15}{dt} &= 0
\end{align*}