CLEiM (Cross Lingual Education in Medicine) is an opensource version of an Intelligent System which integrates information, from various sources, about annotated concepts in medical texts inputted by users, developed by the Intelligent System Group (GSI) at UEM University. It is a real-time system for Multilingual Concept Extraction and NER in the medical domain, scalable to other domains. An installed and full functional version can be found here.
All integrated sources of medical terminology (at this moment are Freebase, MedlinePlus and Snomed CT) are fully accesible from the demo version. However, some of this terminology sources are not published because their licenses restrictions.

To start, insert your medical text into the box. Select the sources with which you desire annotate the inputted text and process it. Use logical filters in order to sort the output, and try to navigate through the links.