Sent_en: 2ms Theories have been around since the 1940s that childhood exposure to infection was related to the development of childhood leukaemia — one, like the working theory of the UK study, said that lack of immune challenge was a factor, another that leukaemia developed as a delayed result of some type of infection.
Sent_yy: Pelbagai teori telah wujud sejak tahun 1940-an bahawa pendedahan kanak-kanak kepada jangkitan adalah berkaitan dengan pembangunan leukemia kanak-kanak - satu, seperti teori kerja kajian UK, berkata kekurangan cabaran imun merupakan satu faktor, satu lagi leukemia yang terhasil kerana akibat tertunda sesetengah jangkitan.