title: Thyroid function tests.
abstract: Understanding basic thyroid physiology is essential to the proper interpretation of thyroid tests. The hypothalamus controls the pituitary gland, which regulates the thyroid in a classic feedback loop. Thyroid hormone levels are determined by thyroid state and thyroid hormone binding. Triiodothyronine (T3) levels may be decreased by nonthyroidal illness or by certain drugs without affecting thyroid status.
mesh_terms: D006801:Humans; D006980:Hyperthyroidism / Q000378:metabolism; D007030:Hypothalamo-Hypophyseal System / Q000502:physiology; D007037:Hypothyroidism / Q000378:metabolism; D013959:Thyroid Diseases / Q000097:blood / Q000175:diagnosis*; D013960:Thyroid Function Tests; D013961:Thyroid Gland / Q000502:physiology*; D013963:Thyroid Hormones / Q000378:metabolism; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
chemical_list: D013963:Thyroid Hormones; D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine