The Shutdown and Government Information Sources
According to the NCBI website "PubMed has been designated to be maintained with minimal staff during the lapse in government funding. The information on this website will be kept as up to date as possible, and the agency will attempt to respond to urgent operational inquiries during this period."
Many other government websites, including the Center for Disease Control, National Science Foundation and NIH are carrying statements to the effect that they are not being updated and that transactions may not be processed. Other websites including USDA.gov, appear to be completely shut down. ERIC, the education research service, is not available at eric.ed.gov, but the Libraries' access via EbscoHost is still functional.