Gao, Yonghui
Wang, Jianhua
Shangguan, Shaofang
Bao, Yihua
Lu, Xiaoli
Zou, Jizhen
Dai, Yaohua
Liu, Junling
Zhang, Ting
Funding for this research was provided by:
The Ministry of Science and Technology of the P. R. China, National “973” project on Population and Health (2007CB11901)
The National Natural Science Foundation of China (81270699, 81070491)