Research with living systems is never simple, scientists say, so there are many possible sources of variation in any experiment, ranging from the animals and cells to the details of lab technique.
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Karen Lorne, diagnosed with Lou Gehrig's disease in July, volunteers weekly with her certified therapy dog, Bailey, at the Ronald McDonald House in Chapel Hill, N.C.
Courtesy of Karen Lorne
Clinical Trials Still Don't Reflect The Diversity Of America
Glenn Lightner in 2012 at age 13. His father searched clinicaltrials.gov for years, to no avail, hoping to find a promising experimental cancer treatment that might save his son's life.
Courtesy of Lawrence Lightner