The portion of the GASTROINTESTINAL TRACT between the PYLORUS of the STOMACH and the ILEOCECAL VALVE of the LARGE INTESTINE. It is divisible into three portions: the DUODENUM, the JEJUNUM, and the ILEUM.
Small Intestine,Intestines, Small,Small Intestines
D008297
Male
Males
D008875
Middle Aged
An adult aged 45 - 64 years.
Middle Age
D005260
Female
Females
D006801
Humans
Members of the species Homo sapiens.
Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000368
Aged
A person 65 years of age or older. For a person older than 79 years, AGED, 80 AND OVER is available.
Elderly
D012189
Retrospective Studies
Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.