atrial premature complex

complex /com·plex/ (kom´pleks)

1. a combination of various things, e.g., a complex of symptoms; see syndrome.

2. sequence (2).

3. a group of interrelated ideas, mainly unconscious, that have a common emotional tone and strongly influence a person's attitudes and behavior.

4. that portion of an electrocardiogram representing the systole of an atrium or ventricle.

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AIDS dementia complex  HIV encephalopathy.

AIDS-related complex  (ARC) a complex of signs and symptoms representing a less severe stage of human immunodeficiency virus (HIV) infection, characterized by chronic generalized lymphadenopathy, fever, weight loss, prolonged diarrhea, minor opportunistic infections, cytopenia, and T-cell abnormalities of the kind associated with AIDS.

anomalous complex  in electrocardiography, an abnormal atrial or ventricular complex resulting from aberrant conduction over accessory pathways.

antigen-antibody complex  a complex formed by the binding of antigen to antibody.

anti-inhibitor coagulant complex  (AICC) a concentrated fraction from pooled human plasma, which includes various coagulation factors; used as an antihemorrhagic in hemophilic patients with factor VIII inhibitors.

atrial complex  the P wave of the electrocardiogram, representing electrical activation of the atria.

atrial premature complex  (APC) a single ectopic atrial beat arising prematurely, which may be associated with structural heart disease.

atrioventricular (AV) junctional escape complex  see under beat.

atrioventricular (AV) junctional premature complex  an ectopic beat arising prematurely in the atrioventricular junction and traveling toward both the atria and ventricles if unimpeded, causing the P wave to be premature and abnormal or absent and the QRS complex to be premature.

branched-chain α-keto acid dehydrogenase complex  a multienzyme complex that catalyzes the oxidative decarboxylation of the keto acid analogues of the branched chain amino acids; deficiency of any enzyme of the complex causes maple syrup urine disease.

calcarine complex  calcar avis.

castration complex  in psychoanalytic theory, unconscious thoughts and motives stemming from fear of damage to or loss of sexual organs as punishment for forbidden sexual desires.

Eisenmenger's complex  a defect of the interventricular septum with severe pulmonary hypertension, hypertrophy of the right ventricle, and latent or overt cyanosis.

Electra complex  the counterpart in females of the Oedipus complex, involving the daughter's love for her father and jealousy or resentment towards her mother; now rarely used since Oedipus complex (q.v.) has come to be applied to both sexes.

exstrophy-epispadias complex  a spectrum of congenital defects of the anterior abdominal wall, ranging from epispadias to exstrophy of the bladder to exstrophy of cloaca.

factor IX complex  a partially purified factor IX fraction also including factor II, VII, and X fractions, from venous human plasma. It is used in the treatment of hemophilia B, replacement of factor VII, and treatment of anticoagulant-induced hemorrhage.

Ghon complex  primary c. (1).

β-glycosidase complex  the enzyme complex comprising lactase and phlorhizin hydrolase activities, occurring in the brush border membrane of the intestinal mucosa and hydrolyzing lactose as well as cellobiose and cellotriose.

Golgi complex  Golgi apparatus; a complex cellular organelle consisting mainly of a number of flattened sacs (cisternae) and associated vesicles, involved in the synthesis of glycoproteins, lipoproteins, membrane-bound proteins, and lysosomal enzymes. The sacs form primary lysosomes and secretory vacuoles.

immune complex  antigen-antibody c.

inclusion complex  one in which molecules of one type are enclosed within cavities in the crystalline lattice of another substance.

inferiority complex  unconscious feelings of inadequacy, producing timidity or, as a compensation, exaggerated aggressiveness and expression of superiority.

junctional premature complex  atrioventricular junctional premature c.

LCMV-LASV complex  a group of antigenically related viruses comprising the Old World arenaviruses. Lassa virus (Lassa fever) and lymphocytic choriomeningitis virus are pathogenic for humans.

Lutembacher's complex  see under syndrome.

major histocompatibility complex  (MHC) the chromosomal region containing genes that control the histocompatibility antigens. In humans, it controls the HLA antigens.

membrane attack complex  (MAC) the pentamolecular complex of components C5b,6,7,8,9 formed in the final pathway of complement activation, inserting into the target cell membrane where it creates a pore and results in cytolysis.

Oedipus complex  the feelings and conflicts occurring in a child that result from sexual attraction to the opposite-sex parent, including envious, aggressive feelings toward the same-sex parent.

pore complex  a nuclear pore and its annulus considered together.

primary complex 

1. the combination of a Ghon focus and a corresponding lymph node focus in primary tuberculosis in children; similar lesions are seen with other mycobacterial and fungal infections.

2. the primary cutaneous lesion at the site of skin infection, e.g., a chancre in syphilis or tuberculosis.

primary inoculation complex , primary tuberculous complex tuberculous chancre.

pyruvate dehydrogenase complex  a multienzyme complex that catalyzes the formation of acetyl coenzyme A from pyruvate and coenzyme A; deficiency of any component of the complex results in lacticacidemia, ataxia, and psychomotor retardation.

QRS complex  the portion of the electrocardiogram comprising the Q, R, and S waves, together representing ventricular depolarization.

sucrase-isomaltase complex  the enzyme complex comprising sucrase and isomaltase activities, occurring in the brush border of the intestinal mucosa and hydrolyzing maltose as well as maltotriose and some other glycosidic bonds.

symptom complex  syndrome.

synaptonemal complex  the structure formed by the synapsis of homologous chromosomes during the zygotene stage of meiosis I.

Tacaribe complex  a group of antigenically related viruses comprising the New World arenaviruses, including Junin virus, the agent of Argentinian hemorrhagic fever, and Machupo virus, the agent of Bolivian hemorrhagic fever.

VATER complex  an association of congenital anomalies consisting of v ertebral defects, imperforate a nus, t racheoe sophageal fistula, and r adial and r enal dysplasia.

ventricular complex  the combined QRS complex and T wave, together representing ventricular electrical activity.

ventricular premature complex  (VPC) an ectopic beat arising in the ventricles and stimulating the myocardium prematurely.

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atrial premature complex (APC).

See premature atrial complex.