http://animeaiko1.deviantart.com/art/MMD-DOWNLOAD-SOS-brigade-213634726
As I understand it those are realtime models for some kind of game? In that case, probably not. Unless someone made available a converter from that game’s format to something more standard. And even then you’d probably have to re-rig them, which in itself is complex enough that you’d have to learn enough to make your own models anyway.
I didn’t actually try this, but they appear to be pmd models.
In which case this old script may work - http://sites.google.com/site/mikumikubeat/tutorials/pmdmod
Another thing to keep in mind is the old 2.49b version has lots of scripts for imports/exports that still work above and beyond the latest Blender version (you’ll have to look, because I don’t know for sure). If it can, save the .blend and append to a 2.6x scene.