It sounds dangerous, or at least uncomfortable, but I have a friend who thinks drinking milk daily will help cure him of lactose intolerance. Are there any studies that indicate that prolonged exposure can acclimate the body to processing lactose? If so, please describe how that is possible.
Very generally speaking I would say it depends on the cause of the intolerance - if it is a primary intolerance (i. e. genetic problem with lactase persistence deficiency, the enzyme for digesting lactose) no additional exposure will cause a change in genetics. Another genetic form of lactose intolerance prevents forming of lactase enzymes.
Secondary intolerance is acquired, i. e. not genetic in origin. Acquiring it usually is accompanied by some sort of intestinal inflammation and is thought to be reversible.
Some more details on this can be found here: https://en.wikipedia.org/wiki/Lactose_intolerance#Causes