The evolution equation for high twist operators is solved in the Double
Logarithmic Approximation for cylinder-type diagrams which dominate in the
limit of large number of colors. The asymptotic behaviour of the parton
correlation function is shown to be determined by the spectrum of the Ising
model for a one-dimensional chain of spin-1/2 magnets.Comment: 17 pages, LATEX, 2 figures appended as uu-encoded fil
