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  The difference between veins and arteries is made.
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  They built and started a medical school
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  Discovered differences between small pox and measles
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  They considered surgery as a profession.
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  The symbol for medicine
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  They stared having health care for the sick people.
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  Outbreak of bubonic plague broke out in Istanbul. Now we know that bubonic plague is a form of contagious and fatal pneumonia.
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  A french woman that tried to practice medicine but was denied.
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  Dissected human bodies and made drawings of everything to help physicians understand where the organs were in the body and start to learn about their function.
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  A French surgeon who restored and reformed the surgical art through his practice.
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  They discovered a vaccine for smallpox
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  set fees for surgeons
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  Performed the first successful transfusion of human blood
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  discovered diphtheria antitoxin
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  Discovered X-Rays
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  America's first cardiologist.
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  Discovered vitamin D
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  Performed the first kidney transplant between identical twins.
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  Implants an artificial heart into patient Barney Clark. Clark lives 112 days.
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  Approved the first human trials of a Zika vaccine.