Karl Landsteiner — Austrian Scientist born on June 14, 1868, died on June 26, 1943

Karl Landsteiner, ForMemRS, was an Austrian and American biologist and physician. He is noted for having first distinguished the main blood groups in 1900, having developed the modern system of classification of blood groups from his identification of the presence of agglutinins in the blood, and having identified, with Alexander S. Wiener, the Rhesus factor, in 1937, thus enabling physicians to transfuse blood without endangering the patient′s life. With Constantin Levaditi and Erwin Popper, he discovered the polio virus in 1909. He received the Aronson Prize in 1926. In 1930 he received the Nobel Prize in Physiology or Medicine. He was awarded a Lasker Award in 1946 posthumously and is recognized as the father of transfusion medicine... (wikipedia)

Owing to the difficulty of dealing with substances of high molecular weight we are still a long way from having determined the chemical characteristics and the constitution of proteins, which are regarded as the principal con-stituents of living organisms.
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