Method
Blood samples are collected in tubes with oxalate or citrate to arrest coagulation by binding calcium. The specimen is then delivered to the laboratory. In order to activate the intrinsic pathway, phospholipid, an activator (such as silica, celite, kaolin, ellagic acid), and calcium (to reverse the anticoagulant effect of the oxalate) are mixed into the plasma sample. The time is measured until a thrombus (clot) forms. This testing is performed by a medical technologist.
The test is termed "partial" due to the absence of tissue factor from the reaction mixture.
Read more about this topic: Partial Thromboplastin Time
Famous quotes containing the word method:
“I know no method to secure the repeal of bad or obnoxious laws so effective as their stringent execution.”
—Ulysses S. Grant (1822–1885)
“The method of painting is the natural growth out of a need. I want to express my feelings rather than illustrate them. Technique is just a means of arriving at a statement.... I can control the flow of paint: there is no accident, just as there is no beginning and no end.”
—Jackson Pollock (1912–1956)
“A method of child-rearing is not—or should not be—a whim, a fashion or a shibboleth. It should derive from an understanding of the developing child, of his physical and mental equipment at any given stage, and, therefore, his readiness at any given stage to adapt, to learn, to regulate his behavior according to parental expectations.”
—Selma H. Fraiberg (20th century)