Department of Nutrition and Food Hygiene;
School of Public Health;
Zunyi Medical University;
Zunyi 563006;
Guizhou;
China;
Experimental Teaching Demonstration Center for Preventive medicine of Guizhou Province;
Zunyi 563006;
Guizhou;
China;
Department of Cross Infection Control;
the Fourth People's hospital of Zunyi;
Zunyi 563004 Guizhou;
China;
Department of Chronic Disease;
Center of Disease Control and Prevention of Zhijin County;
Zhijin 552100;
Guizhou;
China;