Lime juice (which is an acid) acting on acidic stomach is not a neutralization reaction. An antacid (basic) could be used instead to neutralise the acidic stomach.
In the other cases, acidic soil is neutralised by powdered lime (which is basic). Similarly, toothpaste is basic which neutralises the action of bacteria (acidic) present in the mouth and prevent cavities and decays.
Also, shampoos are alkaline which causes small scales on our hair. Using conditioners (acidic) will neutralise it and the scales will close up.