Heterogeneous group of immunocompetent cells that mediates the cellular immune response by processing and presenting antigens to the T-cell receptor. Traditional antigen-presenting cells include MACROPHAGES; DENDRITIC CELLS; LANGERHANS CELLS; and B-LYMPHOCYTES. Follicular dendritic cells (DENDRITIC CELLS, FOLLICULAR) are also considered to be antigen-presenting cells by some authors.

A medical specialty concerned with the hypersensitivity of the individual to foreign substances and protection from the resultant infection or disorder.

Agents that suppress immune function by one of several mechanisms of action. Classical cytotoxic immunosuppressants act by inhibiting DNA synthesis. Others may act through activation of suppressor T-cell populations or by inhibiting the activation of helper cells. While immunosuppression has been brought about in the past primarily to prevent rejection of transplanted organs, new applications involving mediation of the effects of interleukins and other cytokines are emerging.

Hyponatremia and renal salt loss attributed to overexpansion of body fluids resulting from sustained release of VASOPRESSINS (i.e., antiduretic hormone) despite the absence of appropriate stimuli. Associated conditions include medication effect; MENINGITIS; CRANIOCEREBRAL TRAUMA; ENCEPHALITIS; CEREBROVASCULAR DISORDERS; HYDROCEPHALUS; PNEUMONIA; ASTHMA; THYROID DISEASES; and other conditions. This condition may also be idiopathic or result from ectopic (extra-pituitary) production of ADH. (From Joynt, Clinical Neurology, 1992, Ch36, pp59-62)

Inappropriate secretion of anterior pituitary gland hormones. The most common hormones involved in over-secretion are SOMATOTROPIN (which may cause ACROMEGALY) and PROLACTIN (which results in HYPERPROLACTINEMIA). THYROTROPIN; luteinizing hormone (LH); CORTICOTROPIN; and FOLLICLE STIMULATING HORMONE may also be secreted at inappropriate levels. Hypersecretion syndromes are frequently associated with the presence of a pituitary ADENOMA (see also PITUITARY NEOPLASMS).

Disorders affecting amino acid metabolism. The majority of these disorders are inherited and present in the neonatal period with metabolic disturbances (e.g., ACIDOSIS) and neurologic manifestations. They are present at birth, although they may not become symptomatic until later in life.

Disorders characterized by defective transport of amino acids across cell membranes. These include deficits in transport across brush-border epithelial cell membranes of the small intestine (MICROVILLI) and KIDNEY TUBULES; transport across the basolateral membrane; and transport across the membranes of intracellular organelles. (From Nippon Rinsho 1992 Jul;50(7):1587-92)

Disorders affecting amino acid metabolism. The majority of these disorders are inherited and present in the neonatal period with metabolic disturbances (e.g., ACIDOSIS) and neurologic manifestations. They are present at birth, although they may not become symptomatic until later in life.

Disorders affecting amino acid metabolism. The majority of these disorders are inherited and present in the neonatal period with metabolic disturbances (e.g., ACIDOSIS) and neurologic manifestations. They are present at birth, although they may not become symptomatic until later in life.

Abortion in which not all the products of conception have been expelled.