deporting ipad files

I am using Mendeley on desktops and iPad. I can import files on my iPad, which is especially handy for reading and annotating. But how can I 'deport' annotated files from my iPad and still keep them in my Mendeley database? I need this because the memory storage capacity of my iPad is limited. I tried 'delete' on my iPad but that also deleted the file from my desktop and I lost all my annotations.