the National Natural Science Foundation of China30960343;the Special Funds for Teaching Team in the National Level[2009]18;the Joint Fund from the Science and Technology Department of Guizhou Province and Medical College of GuiyangLG [2012]012LG[2012]054;国家自然科学基金30960343;国家级教学团队专项[2009]18;贵州省科技厅、贵阳医学院联合基金资助项目[黔科合LG[2012]012,LG2012]054号