Is it possible to simulate Fluorescence in cycles? It it possible to create a fluorescence shader in cycles?

From Wikipedia:


  Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation.


More specifically, Is it possible to make a shader that emits more light on one wavelength than it receives on that wavelength, while not emitting more total light than it receives?
Fluorescence is emission of light, so it would be natural to use emitter shader with the right rgb value mixed with other shaders -- it should give an accurate emulation of the phenomena. Please note that fluorescence includes time component, so the object might emit more light than it receives at the moment, if it was subjected to source of light earlier.