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What is Which is the following agents is a prerequisite for Prothrombin time (PT) assay? and explain in detail?
Prothrombin time (PT) assay: Time (in seconds) needed for plasma to clot after addition of tissue thromboplastin/tissue factor (e.g., brain extract) and Ca2+ ions Assesses the function of the proteins in the extrinsic pathway (factors VII, X, V, II (prothrombin), and fibrinogen) Prolonged PT can result from a deficiency of factor V, VII, X, prothrombin, fibrinogen, presence of an acquired inhibitor that interferes with the extrinsic pathway Kaolin, silica, glass beads are contact activators that trigger the intrinsic pathway and the first two agents are commonly used in paial thromboplastin time (PTT) assay.