The spleen and splenectomy.
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D006689:Hodgkin Disease / Q000601:surgery; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D011008:Pneumococcal Infections / Q000209:etiology; D018805:Sepsis / Q000209:etiology; D013103:Spherocytosis, Hereditary / Q000601:surgery; D013154:Spleen / Q000293:injuries / Q000502:physiology* / Q000503:physiopathology; D013156:Splenectomy / Q000009:adverse effects*; D013163:Splenomegaly / Q000209:etiology; D013789:Thalassemia / Q000601:surgery; D013921:Thrombocytopenia / Q000601:surgery