INDEPENDENCE DAY. On July 4, 1776, the thirteen colonies claimed their independence from England, an event which eventually led to the formation of the United States.
Polycythemia vera is a rare, chronic disorder involving the overproduction of blood cells in the bone marrow (myeloproliferation). The overproduction of red blood cells is most dramatic, but the production of white blood cells and platelets are also elevated in most cases.
Polycythemia vera is characterized by having too many red blood cells in the bloodstream. This can cause problems because the blood is thicker than it would normally be, which causes an increased risk for blood clots that can cause serious health problems such as heart attack or stroke.