handle the error when pubmed query service at ncbi is not accessible
handle the error when pubmed query service at ncbi is not accessible

and report back a message to the user

SynthSys/seek,Virtual-Liver-Network/seek,HITS-SDBV/nmtrypi-seek,aina1205/nmtrypi-seek,SynthSys/seek,SynthSys/seek,stuzart/seek,aina1205/nmtrypi-seek,HITS-SDBV/nmtrypi-seek,stuzart/seek,Virtual-Liver-Network/seek,SynthSys/seek,HITS-SDBV/seek,HITS-SDBV/nmtrypi-seek,Virtual-Liver-Network/seek,HITS-SDBV/seek,Virtual-Liver-Network/seek,HITS-SDBV/seek,HITS-SDBV/seek,HITS-SDBV/nmtrypi-seek,aina1205/nmtrypi-seek,aina1205/nmtrypi-seek,stuzart/seek