During the poker game at the end of the Episode Col Potter says "I'm from Missouri, but you have shown me enough". Missouri is the Show Me State.
Neomycin is an antibiotic that is mentioned as a new treatment in this episode. Neomycin was discovered in 1949 by microbiologist Selman Waksman and his student Hubert Lechevalier at Rutgers University. Neomycin received approval for medical use in 1952. Rutgers University was granted the patent for neomycin in 1957. Neomycin Is still used today as the active ingredient in the common topical ointment, Neosporine.
When Hawkeye is talking about his childhood, he says went to the swimming hole looking for "pollywogs". In this context pollywog means tadpoles and comes from Middle English polwygle, made up of 'pol' (head) and 'wiglen' ('to wiggle').