》碘染色
》碘染色
)生活史 ■繁殖阶段:滋养体,二分裂法繁殖 ■传播阶段:包囊,在外界抵抗力较强 寄生部位:主要寄生在十二指肠内, 借吸盘吸附肠壁 感染期:成熟四核包囊
THE LIFE CYCLE OF GIARDIA LAMBLIA (the causative agent of giardiasis) Cysts ingested with contaminated water or food Cysts"excyst, "and trophozoites colonize the small intestine Cysts passed in feces Reservoir host(s) (Beavers are often implicated as potential reservoirs (Parasites and Parasitological Resources)
致病 致病机制:尚不完全清楚 机械阻隔,营养竞争-大量虫体覆盖小肠黏 ■机械刺激一吸盘吸附作用 ■化学损伤—分泌产物、代谢产物毒性作用 ■肠内细菌的协同作用 ■宿主免疫状态Ig缺乏;免疫功能低下或 艾滋病患者,均易发生严重的感染