National Medical Journal of China, Volume 92, Issue 13,2012, Pages 920-923, doi:10.3760/cma.j.issn.0376-2491.2012.13.014
National Medical Journal of China, Volume 92, Issue 13,2012, Pages 935-936, doi:10.3760/cma.j.issn.0376-2491.2012.13.018
National Medical Journal of China, Volume 92, Issue 13,2012, Pages 894-898, doi:10.3760/cma.j.issn.0376-2491.2012.13.009
National Medical Journal of China, Volume 92, Issue 13,2012, Pages 873-877, doi:10.3760/cma.j.issn.0376-2491.2012.13.003