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At just 23 years old, Andreas Vesalius, a Belgian anatomist, published his groundbreaking work titled "De Humani Corporis Fabrica" in 1543. Considered one of the most influential books in the history of medicine, it revolutionized the field of human anatomy. Through detailed illustrations and accurate descriptions, Vesalius challenged prevailing medical beliefs based on ancient texts and established anatomy as a science based on direct observation and dissection.