Section 6. Except as provided in section sixty-five, whoever, not being lawfully authorized to practice medicine within the commonwealth and registered under section two, or corresponding provisions of earlier laws, or under section one or two of chapter five hundred and twenty-six of the acts of nineteen hundred and nine, holds himself out as a practitioner of medicine or practices or attempts to practice medicine in any of its branches, or whoever practices medicine under a false or assumed name or under a name other than that by which he is registered, or whoever personates another practitioner, or whoever practices or attempts to practice any fraud in connection with the filing of an application, or whoever files an application under a false or assumed name or under a name other than his own, or whoever personates or attempts to personate another applicant for registration during an examination, shall be punished by a fine of not less than one hundred nor more than one thousand dollars or by imprisonment for not less than one month nor more than one year, or both. A person rendering medical service in violation of this section shall recover no compensation therefor.