The concept of local immunity also suggests that the immunologic apparatus of the lung is available as a target system . 局部免疫的概念还表明，肺的免疫结构是一种靶系统。
The range of immune response in a large random population of animals tends to fellow a normal distribution . 在一个随机挑选的大的动物群体中，免疫应答的强弱是呈正态分布的。
In addition, the immunity produced so far lasts only three to six months, so frequent vaccinations would be necessary . 再则，至此产生的免疫只能持续三至六个月,因此需要经常种痘。
Antibodies are produced by the immune system when something foreign, such as viruses or chemicals, invades the body . 抗体是免疫系统在异物（例如病毒或一些化学物质）侵犯机体时所产生的。
The fall in incidence of whooping cough in the very young is directly related to widespread immunization with suitability . 幼儿百日咳发病率的下降，是与广泛使用一种适宜的免疫法直接有关。
The discovery that an animal can be immunized with only the coat of a virus opens new possibilities in vaccine research . 只用病毒的覆膜就可以使动物免疫的这一发现为疫苗的研究开辟了新途径。
