Inhibitor bound to Factor Xa. Adler et al. (2002) Biochemistry 41, 15514-23. PDB entry 1MQ6 Cumulonimbus Cloud photographed by an Expedition 15 crewmember on the International Space Station, Image Science and Analysis Laboratory, NASA-Johnson Space Center. AIDS drug 2-3 dideoxyadenosine photographed with polarized filter on a microscope by Larry Ostby at National Cancer Institute. Scanning electron microscope image of a breast cancer cell from National Cancer Institute. Solar Dynamic Observatory AIA image at 171 Angstroms on July 9, 2010 Goddard Space Flight Center, NASA