Embolism:Theobstructionof abloodvesselby a foreignsubstanceor a blood clot that travels through the bloodstream, lodgingina blood vessel, plugging the vessel. Foreign substances that can cause embolisms include air bubbles, amniotic fluid, globules offat, clumps of细菌, chemicals (such astalc), and drugs (mainly illegal ones). Blood clots are the most common causes of embolisms. Apulmonary embolusis ablood clotthat has been carried through the blood into the肺动脉(the main blood vessel from the heart to the lung) or one of its branches, plugging that vessel within the lung.
