调查对象来自农场、本院、机关、工厂、学校、幼儿园等,共822名。全部均作常规体检、X线胸部透视、肝功能试验及血、尿、大便常规化验。心、肺、肝、脾作了物理检查。部分作了心电图和双倍二级梯 Survey from the farm, the hospital, offices, factories, schools, kindergartens, etc., a total of 822. All were routine physical examination, X-ray chest, liver function tests and blood, urine, stool routine tests. Heart, lung, liver and spleen made a physical examination. Part of the ECG and double the second ladder