Assertion: aorta | /r/HasProperty | marked at the site
Facets:
Source sentences:
text: While the patient is cooling, the ductus arteriosus is ligated at both the aortic and pulmonary ostia, then transected at its center; the left pulmonary branch, including the first branches in the hilum of the left lung, is separated from the supportive tissue; and the aorta is marked at the site it will be transected, which is just below the pulmonary bifurcation, proximal to where the pulmonary artery will be transected.