NATIONAL MEDICAL JOURNAL OF CHINA, Volume 87, Issue 31,2007, Pages 2228-2231, doi:10.3760/j.issn:0376-2491.2007.31.017
NATIONAL MEDICAL JOURNAL OF CHINA, Volume 87, Issue 31,2007, Pages 2218-2222, doi:10.3760/j.issn:0376-2491.2007.31.015
NATIONAL MEDICAL JOURNAL OF CHINA, Volume 87, Issue 31,2007, Pages 2198-2202, doi:10.3760/j.issn:0376-2491.2007.31.011