Long-term underfunction of the outer portion of the adrenal gland. In medical terms, chronic insufficiency of the adrenal cortex. This may be due to a number of different insults to the adrenal including physical trauma, hemorrhage, and tuberculosis of the adrenal, and destruction of the cells in the pituitary gland that secrete ACTH (adrenocorticotropic hormone) which normally drives the adrenal. Addison’s disease is characterized by bronzing of the skin, anemia, weakness, and low blood pressure. The U.S. President J.F. Kennedy is said to have had Addison disease. Named after the British physician Thomas Addison (1793-1860).When Addison first identified adrenal insufficiency in 1849, tuberculosis (TB) was responsible for 70-90% of cases. As the treatment for TB improved, the incidence of adrenal insufficiency due to TB of the adrenal glands greatly decreased. TB now accounts for around 20% of cases of primary adrenal insufficiency in developed countries.
- Addisonian anemia
Addisonian anemia: A blood disorder caused by a lack of vitamin B12. Patients who have this disorder do not produce the substance in the stomach that allows the body to absorb vitamin B12. This substance is called intrinsic factor (IF). Addisonian anemia, also called pernicious anemia (PA), is characterized by the presence in the blood […]
- Additive genetic effects
Additive genetic effects: A mechanism of quantitative inheritance such that the combined effects of genetic alleles at two or more gene loci are equal to the sum of their individual effects.
- Adducted thumbs with mental retardation
Adducted thumbs with mental retardation: A syndrome with the following characteristic features: neurologically: mental retardation and aphasia (lack of speech) limbs: adducted (clasped) thumbs, absent extensor pollicis longus and/or brevis muscles to the thumb, shuffling gait, and leg spasticity growth: small body size skeleton: lumbar lordosis (sway back) The syndrome is inherited as an X-linked […]
Adduction: Movement of a limb toward the midline of the body. The opposite of adduction is abduction.
- Adductor muscle
Adductor muscle: Any muscle that pulls a body part toward the midline. For example, the adductor muscles of the legs pull the legs toward the midline of the body so the legs are closer together. The word “adductor” comes from the Latin prefix “ad” meaning “toward” + “ducere” meaning “to draw or lead” = “to […]