[phenixbb] how to fix a secondary structure?

Hi phenixers: Recently I am trying to fix a helice, but found that it is so hard for me because of the poor resolution(3.2A) and also a unvisible loop near it, so is there any way to just fix a helice ? can I get it out of the whole structure to refine it? Best regards Xinghua Qin -- Xinghua Qin College of Biological Sciences No.2, Yuan Ming Yuan West Road Haidian District，Beijing，China，100094 Tel: +86-10-62732672