When was the nerve growth factor discovered?

Question

I know that Rita-Levi Montalcini won a Nobel Prize in 1986 for helping to discover the NGF but I can not find when she discovered it. List sources please

Answer 1

Nerve growth factor (NGF) is a hormone-like protein produced by target cells throughout the body that controls growth of axons (fibers) that connect embryonic nerve cells and is also required for their survival. NGF, discovered in the 1950s by the Italian-American biochemist Rita Levi-Montalcini, was the first of a number of growth factors that control cell development.

The chemical, which she named nerve growth factor, was purified and its protein structure determined by Levi-Montalcini's colleague Stanley Cohen in 1953. The two scientists received the 1986 Nobel prize in physiology or medicine for this work. NGF's complete amino acid sequence was accomplished in 1971 by the American biochemists Ruth Hogue Angeletti and Ralph Bradshaw using a technique developed by the Italian biochemists Vincenzo Bocchini and Pietro Angeletti.