Search results
Results from the WOW.Com Content Network
T-cells can be made non-responsive to antigens presented if the T-cell engages an MHC molecule on an antigen presenting cell (signal 1) without engagement of costimulatory molecules (signal 2). Co-stimulatory molecules are upregulated by cytokines (signal 3) in the context of acute inflammation.
Antigen presentation is a vital immune process that is essential for T cell immune response triggering. Because T cells recognize only fragmented antigens displayed on cell surfaces , antigen processing must occur before the antigen fragment can be recognized by a T-cell receptor .
Sideroblastic anemias are often described as responsive or non-responsive in terms of increased hemoglobin levels to pharmacological doses of vitamin B 6. [citation needed] 1- Congenital: 80% are responsive, though the anemia does not completely resolve. 2- Acquired clonal: 40% are responsive, but the response may be minimal.
The medical literature also includes case reports of the recovery of a small number of patients following the removal of assisted respiration with cold oxygen. [18] The researchers found that in many nursing homes and hospitals unheated oxygen is given to non-responsive patients via tracheal intubation.
Habituation is a form of non-associative learning in which an organism’s non-reinforced response to a stimulus decreases after repeated or prolonged presentations of that stimulus. [1] For example, organisms may habituate to repeated sudden loud noises when they learn that these have no consequences. [2]
.ppt, the file format used by Microsoft PowerPoint presentation software; Parts-per notation for parts-per-trillion (more common) or parts-per-thousand (less common) PerlPowerTools, a revitalized of the classic Unix command set in pure Perl; Positive partial transpose, a criterion used in quantum mechanics
An immune response is a physiological reaction which occurs within an organism in the context of inflammation for the purpose of defending against exogenous factors. These include a wide variety of different toxins, viruses, intra- and extracellular bacteria, protozoa, helminths, and fungi which could cause serious problems to the health of the host organism if not cleared from the body.
Tachyphylaxis (Greek ταχύς, tachys, "rapid", and φύλαξις, phylaxis, "protection") is a medical term describing an acute, sudden decrease in response to a drug after its administration (i.e., a rapid and short-term onset of drug tolerance). [1] It can occur after an initial dose or after a series of small doses.