title: In memoriam: Michael J. Welch, PhD, 1939–2012.
authors: Washington University, St. Louis, MO, USA.
authors: Robert J
authors: RJ
authors: Gropler
authors: Barry
authors: B
authors: Siegal
mesh_terms: D049673:History, 20th Century; D009683:Nuclear Medicine / Q000266:history*; D049268:Positron-Emission Tomography / Q000266:history; D011854:Radiochemistry / Q000266:history*; D019275:Radiopharmaceuticals / Q000138:chemical synthesis
chemical_list: D019275:Radiopharmaceuticals