complex
[kom´pleks] 1. the sum, combination, or collection of various things or related factors, like or unlike; e.g., a complex of symptoms (see
syndrome).
2. a group of interrelated ideas, mainly unconscious, that have a common emotional tone and strongly influence a person's attitudes and behavior.
3. that portion of an electrocardiographic tracing which represents the systole of an atrium or ventricle.
AIDS-related complex (ARC) a complex of signs and symptoms occurring in HIV infection including fever, weight loss, prolonged diarrhea, minor opportunistic infections, lymphadenopathy, and changes in cells of the immune system.
antigen-antibody complex here the complex formed by the noncovalent binding of an antibody and antigen. Complexes of antibodies belonging to certain immunoglobulin classes may activate complement. Called also
immune complex.
anti-inhibitor coagulant complex (AICC) a concentrated fraction from pooled human plasma, which includes various coagulation factors. It is administered intravenously as an antihemorrhagic in
hemophilic patients with inhibitors to
coagulation factor VIII.
castration complex in psychoanalytic theory, unconscious thoughts and motives stemming from fear of loss of the genitals as punishment for forbidden sexual desires.
Electra complex libidinous fixation of a daughter toward her father. This term is rarely used, since
oedipus complex is generally applied to both sexes.
factor IX complex a sterile, freeze-dried powder consisting of partially purified
coagulation factor IX fraction, as well as concentrated factor II, VII, and X fractions, of venous plasma from healthy human donors. It is used in the prophylaxis and treatment of bleeding in patients with
hemophilia B, replacement of factor VII in patients deficient in that factor, and treatment of
anticoagulant-induced
hemorrhage. Administered intravenously.
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 shyness or timidity or, as a compensation, exaggerated agressiveness and expression of superiority; based on Alfred Adler's concept that everyone is born with a feeling of inferiority stemming from real or imagined physical or psychological deficiency, with the manner in which the inferiority is handled determining behavior.
interpolated premature ventricular complex a premature ventricular complex that does not interfere with the conduction of the next sinus beat, i.e., it lacks the usual following compensatory pause.
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) C5b,6,7,8,9, the five-molecule complex that is the cytolytic agent of the
complement system.
primary complex 1. the combination of a parenchymal pulmonary lesion (Ghon focus) and a corresponding lymph node focus, occurring in primary tuberculosis, usually in children. Similar lesions may also be associated with other mycobacterial infections and with fungal infections.
2. the primary cutaneous lesion at the site of infection in the skin, e.g., chancre in syphilis and tuberculous chancre.
QRS complex a group of waves seen on an
electrocardiogram, representing ventricular depolarization. Called also
QRS wave. It actually consists of three distinct waves created by the passage of the cardiac electrical impulse through the ventricles and occurs at the beginning of each ventricular contraction. In a normal surface electrocardiogram the R wave is the upward deflection; the first downward deflection represents a Q wave and the final downward deflection is the S wave. The Q and S waves may be extremely weak and sometimes are absent.
One abnormality of the QRS complex is increased voltage resulting from enlargement of heart muscle, which produces increased quantities of electric current. A low-voltage QRS complex may result from toxic conditions of the heart, most commonly from fluid in the pericardium. Pleural effusion and emphysema also can cause a decrease in the voltage of the QRS complex.
VATER complex an association of congenital anomalies consisting of vertebral defects, imperforate anus, tracheoesophageal fistula, and radial and renal dysplasia.
factor
an agent or element that contributes to the production of a result. In epidemiology and statistics called also a variable because the factor may have a number of values. In an experiment a factor is a type of treatment and in the experiment the factor will be represented in different groups by different values. Such a factor may originate spontaneously or be introduced by an investigator.
factor analysisa statistical method for analyzing the correlations between several variables.
antihemorrhagic factorvitamin K.
antinuclear factor (ANF)antinuclear antibody.
antirachitic factorvitamin D.
factor Ba complement component (C3 proactivator) that participates in the alternate complement pathway.
C3 nephritic factora gamma globulin that is not an immunoglobulin, which is found in the plasma of certain individuals with membranoproliferative glomerulonephritis associated with hypocomplementemia; it initiates the alternate complement pathway.
citrovorum factorfolinic acid.
clotting f's, coagulation f'sfactors essential to normal blood clotting, whose absence, diminution or excess may lead to abnormality of the clotting mechanism. See also
clotting factors.
factor Da factor that, when activated, serves as a serine esterase in the alternate complement pathway.
extrinsic factora hematopoietic vitamin that combines with intrinsic factor for absorption from the intestine and is needed for erythrocyte maturation; called also cyanocobalamin and vitamin B12.
F factor, fertility factorthe plasmid that determines the mating type of conjugating bacteria, being present in the donor (male) bacterium and absent in the recipient (female).
f's I to XIIIsee
clotting factors and names of individual factors.
factor VIII activitya test for
hemophilia A; activity is measured in biologic assays using factor VIII-deficient plasma as the substrate.
factor VIII-related antigenvon Willebrand antigen.
factor IX deficiencysee plasma thromboplastin component (PTC).
factor IX complexa sterile, freeze-dried powder containing coagulation factors II, VII, IX and X.
factor X deficiencysee stuart factor.
fibrin stabilizing factorfactor XIII, one of the blood clotting factors that converts soluble fibrin monomer to insoluble, stable fibrin polymer.
intrinsic factora glycoprotein secreted by the parietal cells of the gastric glands, necessary for the absorption of
vitamin B
12 (cyanocobalamin, extrinsic factor). Its absence in humans results in pernicious anemia. Porcine stomach is a very rich source.
LE factoran immunoglobulin (a 7S antibody) that reacts with leukocyte nuclei, found in the serum in systemic lupus erythematosus.
factor loadinga relationship between observable manifestations (or variables) and the underlying factors affecting the variables.
lymph node permeability factor (LNPF)a substance from normal lymph nodes which produces vascular permeability.
lymphocyte transforming factor (LTF)a lymphokine causing transformation and clonal expansion of lymphocytes.
osteoclast activating factorsubstance produced by lymphocytes which facilitates bone resorption.
platelet f'sfactors important in hemostasis that are contained in or attached to the platelets. See also
platelet factors.
platelet-activating factor (PAF)an immunologically produced substance which leads to clumping and degranulation of blood platelets.
R factor, resistance factora bacterial plasmid (R plasmid) which carries genes for antimicrobial resistance; it can be transmitted to other bacterial cells by conjugation, as well as to daughter cells.
release factora protein that binds directly to any stop
codon that reaches the A site on the ribosome.
releasing f'sfactors elaborated in one structure (as in the hypothalamus) that effect the release of hormones from another structure (as from the anterior pituitary gland), including corticotropin releasing factor, melanocyte-stimulating hormone releasing factor and prolactin releasing factor. Applied to substances of unknown chemical structure, while substances of established chemical identity are called releasing hormones.
transfer factor (TF)a factor released from sensitized lymphocytes that has the capacity to transfer delayed hypersensitivity to a normal (nonsensitized) animal. See also
transfer factor.
