The National Library of Medicine has released a beta version of a freely available search engine that provides searching of images from the full-text collection PMC (formerly PubMed Central).
The link to the website is: http://openi.nlm.nih.gov/index.php
From the website:
Open-i lets users retrieve not only the MEDLINE citation information, but also the outcome statements in the article and the most relevant figure from it. Further, it is possible to use the figure as a query component to find other relevant images or other visually similar images. Future stages aim to provide image region-of-interest (ROI) based querying. The initial number of images is projected to be around 600,000 and will scale to millions. The extensive image analysis and indexing and deep text analysis and indexing require distributed computing. At the request of the Board of Scientific Counselors, we intend to make the image computation services available as a NLM service.
Vist our Frequently Asked Questions page for more information and help.