Muslim physicians contributed to the field of medicine, including the subjects of anatomy and physiology: such as in the 15th century Persian work by Mansur ibn Muhammad ibn al-Faqih Ilyas entitled Tashrih al-badan (Anatomy of the body) which contained comprehensive diagrams of the body's structural, nervous and circulatory systems; or in the work of the Egyptian physician Ibn al-Nafis, who proposed the theory of pulmonary circulation. What book was a standard text in universities until the 1800's