  The AdS/CFT correspondence is an exact duality between string theory in
anti-de Sitter space and conformal field theories on its boundary. Inspired in
this correspondence some relations between strings and non conformal field
theories have been found. Exact dualities in the non conformal case are
intricate but approximations can reproduce important physical results. A simple
approximation consists in taking just a slice of the AdS space with a size that
can be related to the QCD energy scale. Here we will discuss how this approach
can be used to obtain the scaling of high energy QCD scattering amplitudes,
glueball masses and Regge trajectories, and the potential energy for a quark
anti-quark pair. This set up is modified to include finite temperature effects
and obtain a deconfining phase trasition.
