从广义上说,病因是指与疾病发生有关的直接的和间接的因素;从狭义上说,是指疾病发生的必不可少的直接原因。人类的生命现象是借适应反应以保持体内平衡,而疾病现象则是这种平衡的破坏,我们可把引起体内平衡破坏的一切条件都归之于病因的范围。病因学研究中常用的术语“危险因素”一词正是指一些与某特定疾病有密切联系、人们暴露接触后会增加得该病危险性的因素。在疾病的致 In a broad sense, the etiology refers to the direct and indirect factors related to the occurrence of disease; in the narrow sense, it refers to the indispensable direct cause of the disease. The phenomenon of human life is to maintain the balance of the body by adapting to the reaction. The disease phenomenon is the destruction of this balance. We can attribute all the conditions that cause the balance and destruction of the body to the cause. The term “risk factor” commonly used in etiological studies refers precisely to factors that are closely related to a particular disease and increase the risk of the disease when people are exposed. Caused by the disease