We check this website, now lexsrv3.nlm.nih.gov is up and dont blocked for our system and other users of the Internet.
So, answer to question: Is lexsrv3 Down Right Now? - NO! lexsrv3 is up!
If you have problem with access to site lexsrv3, and domain lexsrv3.nlm.nih.gov is not avalible.
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