extrinsic pathway

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Related to extrinsic pathway: Prothrombin time, APTT

extrinsic pathway

Hematology The arm of coagulation activation which, like the intrinsic pathway, converges on the common pathway, ie factor X activation; the EP is activated by exposure of blood to tissue factor, circulating factor VII, Ca2+ and phospholipid. Cf Common pathway, Intrinsic pathway.

Extrinsic pathway

One of three pathways in the coagulation cascade.


of external origin.

extrinsic allergic alveolitis
see hypersensitivity pneumonitis.
extrinsic factor
see extrinsic factor.
extrinsic incubation period
the period between infection of the arthropod insect vector and the vector's ability to infect the next vertebrate host.
extrinsic pathway
see coagulation pathways.
extrinsic protein
see membrane proteins.
References in periodicals archive ?
This indicated that tiliroside activates Caspase 8, as the markers of extrinsic pathways of apoptosis mechanism.
Combined": all three pathways are activated; "Extrinsic": only extrinsic pathway is active; "Intrinsic": only intrinsic pathway is active; "Perforin": only perforin pathway is active.
Therapeutic approaches for prevention of lymphocyte apoptosis in murine models of sepsis Strategy Intervention Reference Prevent triggering of Blockade of Fas ligand by using (27) extrinsic pathway Fas fusion protein Prevent triggering of Prevent Fas expression by using (28) extrinsic pathway siRNA Prevent initiation Anti-CD40 agonist antibodies (29) Prevent initiation Treatment with Bcl-2 agonist (30) peptides Prevent triggering of Antiretroviral protease (31) intrinsic pathway inhibitors Prevent execution phase Anticaspase-8 siRNA (28) Prevent execution phase Treatment with caspase (32, 33) inhibitors
By targeting this pathway, rather than the extrinsic pathway, it is expected that TTP889 will provide protection from throboembolism with fewer of the bleeding complications associated with the use of existing anticoagulants.
The induction of apoptosis by cathachunine occurred through an ROS-dependent mitochondria-mediated intrinsic pathway rather than an extrinsic pathway, and was regulated by the Bcl-2 protein family.
The extrinsic pathway is mediated by stimulation of death receptors and is caspase-dependent.
We assume that membrane phospholipids exposed by the slight erythrocytolysis may compete with the PT reagent (thromboplastin) used for the assay of extrinsic pathway factors, causing prolongation of PT.
Either the intrinsic or extrinsic pathway can activate the clotting process.
The PT evaluates the extrinsic pathway of coagulation (factors VII, X, V, II, and fibrinogen).
The extrinsic pathway is triggered by the binding of specific proapoptotic ligands to death receptors and is dependent on the initiator caspase-8 which activates the downstream effector caspases (caspase-3, -6 and -7), inducing a cascade of caspases.
The extrinsic pathway induces apoptosis through an active, instructive process mediated by cell surface death receptors that transmit apoptotic signals when bound by their cognate death ligand.