Cabaret J
Ann Parasitol Hum Comp. 1984;59(4):369-78.
Land-snails (Otala lactea, Theba pisana, Cochlicella ventricosa and C. conoidea) previously infected experimentally by protostrongylids were reinfected at different time-lags, from one day to 126 days. The efficacy of daily reinfections was nil. The susceptibility of all species of snails was lowered for reinfection at short time-lags (up to 15 days) and enhanced for long time lags (over 21 days). The former phenomenon was called limitation and the latter, facilitation. It is suggested that limitation is related to the survival of penetrated first-stage larvae and that facilitation is induced by a better penetration of first-stage larvae.
先前已通过原圆线虫进行实验性感染的陆地蜗牛（乳白奥塔螺、突脐筛豆螺、凸旋螺和圆锥旋螺）在1天至126天的不同时间间隔再次感染。每日再次感染的效果为零。所有蜗牛种类在短时间间隔（最多15天）再次感染时易感性降低，而在长时间间隔（超过21天）时易感性增强。前一种现象称为限制，后一种现象称为促进。有人认为，限制与已侵入的第一期幼虫的存活有关，而促进是由第一期幼虫更好的侵入诱导的。
