cobalamin bacteria measurement radioactivity isolated cobalamin shown bacteria convert available cobalt methylcobalamin medicine pet positron emission tomography scans commonly used diagnostic purposes radiative tracer injected intravenously patient taken pet machine radioactive tracer releases radiation outward patient cameras machine interpret radiation rays tracer pet scan machines use solid state scintillation detection high detection efficiency nai tl crystals absorb tracers radiation produce photons
Natural science Chemistry Radiochemistry