The so-called microNMR chip, which uses magnetic nanoparticles to measure proteins and other chemical compounds in tumors, requires only tiny amounts of tissue to make a diagnosis, researchers said.

The body uses two basic types of fuel: fat and carbohydrates (proteins serve primarily to maintain and repair tissue, not to power muscles).

To his delight, the extracted tissue thrived and grew, and many of the cells in the resulting culture did indeed contain proteins known to be characteristic of neural stem cells.