The absence of deviations from the Standard Model for the differential cross
section dσ/dQ2 at HERA is used to set limits on electron quark
compositeness scale and on new vector bosons, especially the hadrophilic one
recently introduced as a possible explanation for LEP/SLC and CDF anomalies.Comment: Latex file, 7 pages and 1 ps fig, few comments on others experiments
are added, results are unchanged. To appear in Phys. Let.