  It is demonstrated that properly reduced transport coefficients
(self-diffusion, shear viscosity, and thermal conductivity) of Lennard-Jones
fluids along isotherms exhibit quasi-universal scaling on the density divided
by its value at the freezing point. Moreover, this scaling is closely related
to the density scaling of transport coefficients of hard-sphere fluids. The
Stokes-Einstein relation without the hydrodynamic diameter is valid in the
dense fluid regime. The lower density boundary of its validity can serve as a
practical demarcation line between gas-like and liquid-like regimes.
