When people eat raw or incompletely cooked pork containing cysticerci , the cysticerci are stimulated by the bile in the alimentary canal and retract their heads so as to hook onto the intestinal mucosa . proglottids segments grow continuously from their necks and form adult worms in two to three months . usually , there is one adult worm in the human body , but there may also be several of them 人们生食或摄食污染熟食或未煮透的含囊尾蚴的猪肉时,含囊尾蚴在消化道内受到胆汁的刺激,头节翻出,固着在肠粘膜,从颈部不断长出节片,约经二到三个月,发育为成虫,人体内通常寄生一条成虫,也可寄生数条。