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  Thomas Willis first noted the sweet smell of urine and diabetes.
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  John Rollo, Surgeon-General to the Royal Artillery, treated a patient by dietary restriction.
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  Claude Bernard discovered that the liver stored glycogen and secreted a sugary substance (glucose) into the blood. He assumed that it caused the diabetes. He later found out that when he messed with the brain stem, he caused temporary diabetes.
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  Von Mering found that when one removes ones pancreas, they have diabetes.
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  Fredrick Banting discovered insulin and tested it one dogs.
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  A 14-year-old boy became the first human patient to receive insulin made by Banting and Best. However, this failed and was given a purified injection developed by Collip later that month.
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  Lente insulin was introduced.
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  The scientific investigation of diabetes was improved by the technique of immunoassay by Solomon Berson and Rosalind Yalow.