Since 2002, HubMed has been providing RSS feeds for PubMed search results. In 2005, PubMed itself started offering RSS feeds, but I've kept HubMed's RSS and Atom feeds running until this year, as they're easier to set up and contain links back to HubMed for extra features.
Still, as PubMed's feeds should be good enough for most purposes, I've been considering stopping HubMed's feeds, and the demise of Google Reader seemed like a good incentive to do some spring cleaning. They were quite inefficient old scripts, which made the shared hosting provider unhappy, so today I decided to switch the feeds off.
As there's no other way to communicate with feed subscribers, I've replaced each feed with a notice to this effect, and encourage anyone still relying on these feeds - for whom PubMed's feeds are not a suitable alternative - to leave a comment below, or send me an email and discuss how they've been using feeds to receive updates.
Apart from the feeds, most of the rest of HubMed is still running: try the new version, which includes article activity metrics.