text: Approved Stem Cells' Potential Questioned  All of the human embryonic stem cells available to federally funded scientists under President Bush's three-year-old research policy share a previously unrecognized trait that fosters rejection by the immune systems, diminishing their potential as medical treatments, new research indicates.
inputs: Approved Stem Cells' Potential Questioned  All of the human embryonic stem cells available to federally funded scientists under President Bush's three-year-old research policy share a previously unrecognized trait that fosters rejection by the immune systems, diminishing their potential as medical treatments, new research indicates.