Medical Examination of Giant Panda, by Cohen, Jessie, 1983, Smithsonian Archives - History Div, With help from Edward Ruley (c.), chairman of the Nephrology Department at Children's Hospital, the National Zoological Park's chief veterinarian Mitchell Bush (lower r.) and zoo physiologist David Wildt (upper l.) conducted a laparoscopic exam and biopsy of one of Ling-Ling's kidneys on December 8, 1983, at the Zoo's hospital..