Definition is a rhetorical mode that can be used in something smaller or shorter than a full paper. You can use extended definition for several paragraphs only in a paper of much greater length. You also can add to a paper a one-paragraph definition--like a brief encyclopedia definition.
Immunodeficiency: Therapies include thymus transplantation and adoptive transfer of mature T cells (ATMTC) for individuals with complete DiGeorge syndrome and appropriate prophylaxis measures and monitoring autoimmune complications for incomplete or partial DiGeorge syndrome.
Adverse effects are concentration-dependent, and are rare when plasma digoxin concentration is <0.8 nanograms/mL. They are also more common in patients with low potassium levels (hypokalemia), since digoxin normally competes with K+ ions for the same binding site on the Na+/K+ ATPase pump.