Doctors at Massachusetts-based Partners HealthCare may no longer accept gifts and meals from drug and device firms, or travel the country as paid members of company "speakers bureaus," as the hospital and physician network adopts tougher restrictions to counter industry's influence over the drugs and treatments physicians prescribe. Partners, which includes the Harvard-affiliated Massachusetts General and Brigham and Women's hospitals in Boston, also is placing new limits on how physicians interact with company sales representatives and increasing oversight of these relationships.