Probiotics such as bifidobacteria are typically used in cases when a disease occurs or might occur due to a kill-off of normal bacteria. For example, treatment with antibiotics can destroy disease-causing bacteria, but also normal bacteria in the GI (gastrointestinal) and urinary tracts.
The 3-place Hiller Model 360, military H-23 Raven, was based on the U.S. Navy UH-12, which was first flown in 1948. The H-23 Raven performed as a utility, observation, and MedEvac helicopter during the Korean war.
The Sikorsky S-51 helicopters were pressed into service early in the war as aerial ambulances. These helicopters could carry two crewmembers and a wounded soldier. There was so little room in the narrow fuselage for the stretcher that the soldier's legs stuck out the side of the helicopter from the knees down.