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  Egyptians used bloodletting to try to cure diseases
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  Greeks distinguished between arteries and veins
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  Anton Van Leeuwenhoek viewed blood cells under a microscope
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  The first blood transfusion was performed
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  Karl Landsteiner discovered three blood types: A, B, O
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  Alfred Decastello discovered the fourth blood type AB
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  Percy Oliver established the first blood donor service
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  The Mayo Clinic developed a method to store blood for transfusions
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  Dr. Bernard Fantus established the first blood bank
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  Karl Landsteiner discovered the Rh protein
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  The first case of AIDS was discovered in the Congo
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  Robert Gallo identified the virus causing AIDS
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  Development of the ELISA test to screen for diseases such as HIV
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  Scientists began developing blood-screening tests for infections diseases.