  A novel approach to parton distributions parameterization in terms of quantum
statistical functions is here outlined. The description, already proposed in
previous publications, is here improved by adding to the statistical
distributions an unpolarized {\it liquid} component. This new contribution to
fermion partons is able to reproduce the expected low $x$ behaviour of
structure functions. The analysis provides a satisfactory description of
polarized and unpolarized deep inelastic data and shows a possible connection
between the Gottfried and Bjorken sum rules.
