释义 |
DictionarySeeoccult bloodEncyclopediaSeebleedingoccult bleeding
bleeding [blēd´ing] 1. escape of blood from an injured vessel; see also hemorrhage.2. phlebotomy.dysfunctional uterine bleeding bleeding from the nonmenstruating uterus when no organic lesions are present.implantation bleeding that occurring at the time of implantation of the zygote in the decidua.occult bleeding escape of blood in such small quantity that it can be detected only by chemical tests or by microscopic or spectroscopic examination.bleeding time the time required for a standardized wound to stop bleeding. The bleeding time test is used as a screening procedure to detect both congenital and acquired platelet disorders; it measures the ability of platelets to arrest bleeding and hence gives an estimate of platelet number and level of functioning. There are several methods of performing the bleeding time. In Ivy's test, incisions are made on the forearm, a sphygmomanometer is inflated to a standard of 40 mm around the upper arm, and the time until cessation of bleeding is recorded. The template method is a variation in which a template with a slit in it is laid on the forearm, and the slit and the knife making the skin incision are both standardized. The most widely used template is the Simplate. Normally bleeding will cease in 2 to 9 minutes. Qualitative platelet disorders, thrombocytopenia (platelet count of less than 100,000/mm3), and the use of aspirin will prolong the bleeding time.oc·cult bloodblood in the feces in amounts too small to be seen but detectable by chemical tests.occult bleeding See Occult blood. |