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.
Medics gently carry a wounded American soldier towards a Bell H-13 helicopter for evacuation to emergency treatment, 23 July 1953. An M-43 Dodge Ambulance is in the background. At the outset of the Korean War, the U.S. military was still equipped only with a small number of World War II helicopters. There was no doctrine to prescribe their use.