I think that the research that Robin Warren and Barry Marshall won their 2005 Nobel Prize for medicine for it pretty cool.
They are Australian scientists who discovered a bacterium in 1982 (Helicobacter pylori) that they suspected was a major cause of stomach ulcers. People didn’t believe their theory, so to prove them wrong Dr Marshall drank a suspension of the H. pylori and promptly developed a stomach ulcer. He then reinforced his work by treating his H. pylori infection with antibiotics and curing his stomach ulcer.
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