PubMed “Results by year” and PubMed Central “PMC images search” are new tools that will appear in the discovery (i.e., right-hand) column.
“Results by year” is a timeline that appears when there are 10,000 or more citations for your search results. You can see the number of citations for each year by hovering over the bars in the timeline. Click the right and left arrows to display older or newer years; click the individual bars in the timeline to display the results for a single year.
“PMC images search” will be displayed for PubMed search results that meet certain criteria, e.g., results with a minimum of 250 citations, filters are not active, the search does not include Boolean operators, the search retrieves a minimum of 4 relevant images calculated using a term weighted algorithm. To enlarge an image, hover over the thumbnail.