Glenn Lightner in 2012 at age 13. His father searched for years, to no avail, hoping to find a promising experimental cancer treatment that might save his son's life. Courtesy of Lawrence Lightner hide caption

itoggle caption Courtesy of Lawrence Lightner

Truvada can dramatically reduce the risk of HIV infection when taken as a preventative medicine — if taken every day. Studies are underway to determine if young people are likely to take the pill consistently. Justin Sullivan/Getty Images hide caption

itoggle caption Justin Sullivan/Getty Images

U.S. funding for medical research by source, 1994-2012. (Data were adjusted to 2012 dollars using the Biomedical Research and Development Price Index.) American Medical Association hide caption

itoggle caption American Medical Association

Postdoctoral researcher Jennifer Foulke-Abel holds the gut-on-a-chip inside the lab at Johns Hopkins School of Medicine. Richard Harris/NPR hide caption

itoggle caption Richard Harris/NPR

Avian influenza, or bird flu, causes an infectious and contagious respiratory disease. In the lab, several scientists have made the H5N1 strain more contagious, a controversial line of research. James Cavallini/ScienceSource hide caption

itoggle caption James Cavallini/ScienceSource

Dr. Harold Varmus, a Nobel Prize winner, cancer biologist and director of the National Cancer Institute. Manuel Balce Ceneta/AP hide caption

itoggle caption Manuel Balce Ceneta/AP

Tom Murphy, 56, in his home in Gainesville, Va., was diagnosed with ALS four years ago. An experimental drug seems to have slowed the progression of his disease, he says, though most ALS patients aren't as lucky. T.J. Kirkpatrick for NPR hide caption

itoggle caption T.J. Kirkpatrick for NPR

Randen Patterson left a research career in physiology at U.C. Davis when funding got too tight. He now owns a grocery store in Guinda, Calif. Max Whittaker/Prime for NPR hide caption

itoggle caption Max Whittaker/Prime for NPR

The CDC's director, Tom Frieden, testified before a congressional subcommittee Wednesday regarding a recent anthrax incident and lab safety improvements he is instituting. AFP/Getty Images hide caption

itoggle caption AFP/Getty Images

Particles of H5N1 virus — a particularly dangerous type of bird flu that can infect people — attack lung cells. Chris Bjornberg/Science Source hide caption

itoggle caption Chris Bjornberg/Science Source

President Obama has pledged millions of dollars to fuel research into understanding the workings of the human brain. Zephyr/Science Source hide caption

itoggle caption Zephyr/Science Source

Bob Adams is a lab animal veterinarian at Johns Hopkins University. Maggie Starbard/NPR hide caption

itoggle caption Maggie Starbard/NPR