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.
It was the fastest Soviet military fighter aircraft of the Korean War and was deployed from 1949 to 1969. DH 103 Hornet 472 mph. Set a cross-country speed record on 9/18/49. Deployed from 1946 to 1956.