I had two pubs, one as a co-author in journal of Immunology and one as first author in cell and development bio. I dont know how helpful it was, all the private schools i applied too gave me an interview save princeton and non of the state schools so far. once you get to the top schools, from what i know, (my proff was on the admissions committee at Princeton) its a crap shoot. They accepted one guy who only had two LoR rather than the normal three. It really is a flip of a coin.