John Kerry (search) endorsed Nancy Reagan's efforts to help find a cure for Alzheimer's disease and challenged the Bush administration Saturday to relax restrictions on stem cell research to pursue potential cures for that and other illnesses.

Ethical questions raised by the use of human embryos can be resolved through "good will and good sense," Kerry said in the Democrats' weekly radio address. Researchers can find the cures that are there, "if only they are allowed to look."

The Democrats' presumed candidate to face President Bush in November said that Mrs. Reagan "told the world that Alzheimer's had taken her own husband to a distant place, and then she stood up to help find a breakthrough that someday will spare other husbands, wives, children and parents from the same kind of heartache."

The Bush-Cheney campaign (search) defended the president's record on stem cell research as ensuring that it is conducted "in ways that respect human dignity and help build the culture of life."

"Under President Bush's thoughtful leadership, for the first time federal dollars are supporting human embryonic stem cell research consistent with the ethical guidelines" he put in place, said campaign spokesman Scott Stanzel.

Bush signed an executive order in August 2001 that limited federal help to financing stem cell research on 78 embryonic stem cell lines then in existence. Because day-old embryos are destroyed when stem cells are extracted, the process is opposed by some conservatives who link it to abortion.

Kerry said stem cells "have the power to slow the loss of a grandmother's memory, calm the hand of an uncle with Parkinson's, save a child from a lifetime of daily insulin shots or permanently lift a best friend from his wheelchair."

Shortly before Reagan's death, Kerry and 57 other senators asked Bush to relax the restrictions, and Mrs. Reagan has long argued that using stem cells from embryos could lead to cures for a number of diseases.

Since she spoke out at a research fund-raiser in May for renewed government commitment to stem cell research, experts have said finding a cure to Alzheimer's (search), because of how it attacks the brain, would pose a far more daunting challenge than other conditions through the stem cells approach.

Kerry said financing of stem cell research must be a priority in universities and the medical laboratories, as well as federal agencies like the National Institutes of Health and the National Science Foundation.

"If we pursue the limitless potential of our science, and trust that we can use it wisely, we will save millions of lives and earn the gratitude of future generations," Kerry said.