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  First discovery of pulmonary circulation, or the flow of blood to and from the lungs.
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  First drawing of vein valves.
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  First person to observe red blood cells.
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  first time the capillary system was observed.
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  Performed the first blood transfusion in animals. This eventually led to blood transfusions in humans.
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  Transfuses teenage boy with lambs blood.
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  publishes book on blood coagulation and his success at arresting clotting.
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  First unpublished human to human blood transfusion.
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  First recorded human to human blood transfusion.
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  discovery that small cell fragments from the bone marrow make up the majority of clots formed in blood vessels these cells are later called platelets.
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  Discovery of the three major types of blood: A, B, and C. Finds that different blood types cannot mix.
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  Fourth type of blood, type AB, discovered.
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  First transfusion using cross matching, and over the next several years virtually eliminates transfusion reactions.
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  First to propose testing donors blood prior to transfusion.
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  Adding sodium to blood will prevent it from clotting.
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  The optimum concentration of sodium citrate is formulated that can be mixed with donor blood to prevent coagulation
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  Citrated blood can be refrigerated for a few days before transfusion.
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  A solution of citrate-glucose is created to help preserve blood for a few weeks before transfusions.
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  First blood depot.
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  Begins running a blood donor service out of his house.
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  Soviets are the first to establish facilities that collect and store blood for use in transfusions at hospitals.
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  First to perform a blood transfusion with cadaver blood.
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  Anesthesiologists in Rochester first to begin storing citrated blood and utilizing it for transfusions within hospitals.
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  Established blood transfusion service that collects, tests, and stores blood to be shipped during the Spanish Civil War.
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  Coins the term "blood bank."
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  Discover Rh blood group.
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  First able to unravel the structure of hemoglobin, the protein within red blood cells that carries oxygen.
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  The responsibility of regulating the blood banking industry is transfered from the Divisions of Biologics Standars to the Food and Drug Administration.
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  The first case of Gay-related immunodeficiency (GRID), now know as Acquired Immune Deficiency Syndrome (AIDS).
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  Discovers that AIDS is a blood born disease.
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  The virus causing AIDS is isolated and labled lymphadenopathy- associated virus.
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  The virus that causes AIDS is identified and called HTLV lll (human T-cell lymphotropic virus)
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  After multiple AMericans have been diagnosed with AIDS after blood transfusions, the ELISA test, the first bllood-screening test. is licensed by the US governmeant to detect the presence of HIV antibodies.
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  A series of more sensative blood-screening test are created to test for diseases in donated blood.