Besides merchants, a great number of physicians were among the Spanish Jews in Amsterdam: Samuel Abravanel, David Nieto, Elijah Montalto, and the Bueno family; Joseph Bueno was consulted in the illness of Prince Maurice (April 1623). Jews were admitted as students at the university, where they studied medicine as the only branch of the science of practical use to them, for they were not permitted to practice law, and the oath they would be compelled to take excluded them from the professorships. Neither were Jews taken into the trade-guilds: a resolution passed by the city of Amsterdam in 1632 (the cities being autonomous) excluded them. Exceptions, however, were made in the case of trades that related to their religion: printing, bookselling, and the selling of meat, poultry, groceries, and drugs. In 1655 a Jew was, exceptionally, permitted to establish a sugar-refinery.