{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T00:14:28Z","timestamp":1781741668950,"version":"3.54.5"},"reference-count":13,"publisher":"Cambridge University Press (CUP)","issue":"1","license":[{"start":{"date-parts":[[2009,4,6]],"date-time":"2009-04-06T00:00:00Z","timestamp":1238976000000},"content-version":"unspecified","delay-in-days":12848,"URL":"https:\/\/www.cambridge.org\/core\/terms"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Parasitology"],"published-print":{"date-parts":[[1974,2]]},"abstract":"<jats:p>Previously immunized rats of different ages were exposed either to one large, or several small challenge infections with the nematode, <jats:italic>Nippostrongylus brasiliensis.<\/jats:italic> The number of secondary worms harboured by each of these rats was then determined on the fourteenth day after exposure to challenge. It was found that worms adapted more efficiently to host immunity when both (<jats:italic>a<\/jats:italic>) the rats were less than 11 weeks old when challenged and (<jats:italic>b<\/jats:italic>) the challenge was given in small repeated doses over a period of weeks. The age of the rats on exposure to the immunizing primary infection, however, had little or no affect <jats:italic>per se<\/jats:italic> on the subsequent establishment of immune-adapted worms. It is tentatively suggested that the failure of worms to adapt effectively to the acquired immunity of older rats resulted from the acquisition by these rats of a fully competent cellular immune response.<\/jats:p>","DOI":"10.1017\/s0031182000045327","type":"journal-article","created":{"date-parts":[[2009,6,5]],"date-time":"2009-06-05T17:02:34Z","timestamp":1244221354000},"page":"13-17","source":"Crossref","is-referenced-by-count":8,"title":["<i>Nippostrongylus brasiliensis<\/i>: observations on factors affecting the establishment of secondary worm populations in rats"],"prefix":"10.1017","volume":"68","author":[{"given":"D. Conwil","family":"Jenkins","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"56","published-online":{"date-parts":[[2009,4,6]]},"reference":[{"key":"S0031182000045327_ref013","doi-asserted-by":"publisher","DOI":"10.1016\/0014-4894(71)90021-X"},{"key":"S0031182000045327_ref007","doi-asserted-by":"publisher","DOI":"10.1016\/0020-7519(72)90038-0"},{"key":"S0031182000045327_ref012","doi-asserted-by":"publisher","DOI":"10.1017\/S0031182000072139"},{"key":"S0031182000045327_ref008","doi-asserted-by":"publisher","DOI":"10.1016\/0020-7519(72)90073-2"},{"key":"S0031182000045327_ref001","doi-asserted-by":"publisher","DOI":"10.1017\/S0031182000029656"},{"key":"S0031182000045327_ref002","first-page":"1","article-title":"The suppression of rejection of Nippostrongylus brasiliensis in lactating rats: the nature of the immunological defect","volume":"22","author":"Dineen","year":"1972","journal-title":"Immunology"},{"key":"S0031182000045327_ref003","doi-asserted-by":"publisher","DOI":"10.1038\/2111310a0"},{"key":"S0031182000045327_ref004","doi-asserted-by":"publisher","DOI":"10.1016\/0014-4894(68)90053-2"},{"key":"S0031182000045327_ref005","first-page":"242","volume-title":"The Reaction of the Host to Parasitism","author":"Jarrett","year":"1968"},{"key":"S0031182000045327_ref010","first-page":"767","article-title":"Protective immunity to Nippostrongylus brasiliensis in the rat: central role of the lymphocyte in worm expulsion","volume":"22","author":"Keller","year":"1972","journal-title":"Immunology"},{"key":"S0031182000045327_ref011","doi-asserted-by":"publisher","DOI":"10.2307\/3276966"},{"key":"S0031182000045327_ref009","doi-asserted-by":"publisher","DOI":"10.1017\/S0031182000072310"},{"key":"S0031182000045327_ref006","doi-asserted-by":"publisher","DOI":"10.1017\/S0031182000044152"}],"container-title":["Parasitology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.cambridge.org\/core\/services\/aop-cambridge-core\/content\/view\/S0031182000045327","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,5,29]],"date-time":"2019-05-29T21:40:58Z","timestamp":1559166058000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.cambridge.org\/core\/product\/identifier\/S0031182000045327\/type\/journal_article"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1974,2]]},"references-count":13,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1974,2]]}},"alternative-id":["S0031182000045327"],"URL":"https:\/\/doi.org\/10.1017\/s0031182000045327","relation":{},"ISSN":["0031-1820","1469-8161"],"issn-type":[{"value":"0031-1820","type":"print"},{"value":"1469-8161","type":"electronic"}],"subject":[],"published":{"date-parts":[[1974,2]]}}}