  Withdrawm.
  Public data of COBE-DMR are not perfectly subtracted from dipole. Therefore,
the Galactic latitude dependence is affected by the remnants of the dipole and
the results previously announced in this paper about this are not valid.
  Anyway, the suspect of a high Galactic contamination announced in another
paper (Lopez-Corredoira 1999; A&A 346, 369) is still valid and to be
considered.
  Thanks are given to Ted Bunn for helpful discussions which made me realize of
the problem with the dipole.
