In the long history of Kaiser Permanente, several executives — including Henry J. Kaiser himself — worked their way up from poverty. Clifford Keene, MD, was another. Keene was the first president and CEO of Kaiser Foundation Hospitals and Health Plan. See his story in the May 2013 issue of Hank, the Kaiser Permanente Labor Management Partnership magazine, about Keene's pride in having both been an ironworker and a surgeon.
He reflected on it when commenting on a successful infant bowel surgery while serving as a cancer specialist at the University of Michigan State Hospital at the end of the 1930s:
“When I was in the army I further developed my interest in bowel surgery, and reconstruction of all kinds, and also in plastic procedures, orthopedic procedures, all of which were an extension of my interest i n doing things with my hands. I [had been] a steel worker and it was satisfying to correct things with my hands.”
Here's a link to U.C. Berkeley's Regional Oral History Office 1985 interview.