[Bioperl-l] about biblio

[Nicolas Turenne]

Hello,
I am using biblio module from bioperl to download pubmed abstract.
if i do the query "actb" on the pubmed site  
(http://www.ncbi.nlm.nih.gov/sites/entrez)
i get 165 hits

But using bioperl, if i do

use Bio::Biblio;
my $biblio = Bio::Biblio->new
    (-access          => 'soap',
     -location        => 'http://www.ebi.ac.uk/openbqs/services/MedlineSRS',
     -destroy_on_exit => '0');
my @ListID = @{ $biblio->find ("actb")->get_all_ids };

i get 228 hits, so i dont understand the difference

thank for help
Nicolas