MTHFR C677T and MTR A2756G polymorphisms and the homocysteine lowering efficacy of different doses of folic acid in hypertensive Chinese adults oleh Qin Xianhui, Li Jianping, Cui Yimin, Liu Zeyuan, Zhao Zhigang, Ge Junbo, Guan Deming, Hu Jian, Wang Yanni, Zhang Fumin, Xu Xin, Wang Xiaobin, Xu Xiping, Huo Yong