Some outbreaks can be constituted-of-or-filled-with gastrointestinal disease.
(Flu virus) may be detected in a gastrointestinal tract of children.
A physician may specialize in diseases of a gastrointestinal tract.
A gastrointestinal hormone may be produced by epithelial cells.
A gastrointestinal hormone may stimulate a secretion of water.
A gastrointestinal hormone may stimulate a secretion of pancreatic enzymes.
A gastrointestinal hormone may be stimulated by presence of (fatty acids).