Not able to create connections to http://dmoz.org/Health/Conditions_and_Diseases/Neurological_Disorders/Muscle_Diseases/Stiff-Person_Syndrome/ from your server.
The reason might be a firewall, proxy, or http://dmoz.org/Health/Conditions_and_Diseases/Neurological_Disorders/Muscle_Diseases/Stiff-Person_Syndrome/ or your web hosting company might be blocking outside connections.
Another possibility is a timeout because of slowdown in internet itself.