Is there any field in which applicants to PhD programs (in any part of the world) usually have publications?
I'll point toward the Max Planck School for Computer Science,
IMPRS-CS, if I remember correctly they used to have even stronger wording than the current 


  A successful candidate must...  have performed research and published (or submitted for publication) the results


But the MPIs are not the norm. Mostly, you would be fine with just your Masters thesis in math, comp sci, biology, or chemistry.