Jewish doctors often had high reputations in the High Middle Ages. Secular and spiritual princes, and even emperors and popes, had Jewish doctors to treat them. Frankfurt also had its Jewish doctors in the 14th century, before the Judengasse was built, and these treated both Christians and Jews. The Jewish doctor Jacob von Straßburg was even appointed city surgeon by the Frankfurt city council. Women also followed this profession, like doctor Gnenlin. Jewish doctors came under increasing pressure from the 16th century onwards. The latent antisemitism in the Reformation and fear of competition on the part of Christian doctors made it difficult for them to practice. In Frankfurt, the Christian doctors pushed through a regulation in 1574 requiring their Jewish colleagues to pass a special examination in order to practise, no matter what university degrees they had elsewhere. Up until the emancipation of the Jews, Jewish doctors were increasingly limited to treating Jewish patients only, although Christians repeatedly sought their advice despite all difficulties. From the 17th century the Jewish community employed two fulltime community doctors, including such prominent doctors of their time as Delmedigo. There were exact instructions and contractual clauses governing their rights and duties: for example, they were required to treat poor people without charge, and exact fees were laid down for treating wealthy patients. Doctors were only allowed to take a larger fee if the patient paid it voluntarily. To ensure the health care of the Jewish population the community doctors were not allowed to leave the city for any length of time without the approval of the community leadership.