| 释义 |
metacyclic, a. Math.|mɛtəˈsɪklɪk|
[f. meta- + cycle n. + -ic.]
Pertaining to the permutation of a set of elements in a cycle. (Cent. Dict. 1890.)
Add:[A.] 2. Biol. and Med. [ad. F. métacyclique (coined by E. Brumpt 1913, in Bull. de la Soc. de Path. Exotique VI. 168).] Designating the form that some trypanosomes attain in the intermediate, invertebrate host, in which they are infective for the vertebrate host.
1926C. M. Wenyon Protozool. I. 344 In the case of the development of trypanosomes in the invertebrate, the final infective forms which pass back to the vertebrate have the trypanosome structure, and have been developed from attached or haptomonad forms of the crithidia type. These infective forms have been termed metacyclic trypanosomes by Brumpt (1913). 1964M. Hynes Med. Bacteriol. (ed. 8) xxi. 323 After this interval large numbers of slender metacyclic forms appear in the body cavity of the louse, which remains infective for life. 1978Nature 22 June 613/1 The trypanosomes causing the various forms of this disease..are transmitted by tsetse flies (Glossina spp.) in whose internal organs they undergo a complicated cycle of development before they reach the infective metacyclic stage in the fly's saliva. 1987Oxf. Textbk. Med. (ed. 2) I. v. 515/2 Trypanosomes of the T. brucei group are elongated parasites... Metacyclic trypanosomes are similar to the blood forms.
B. n. Biol. and Med. A metacyclic trypanosome.
1947Ann. Trop. Med. & Parasitol. XLI. 11 We have seen metacyclics with two kinetoplasts and two nuclei, but we have not seen further evidence of splitting and separation. 1955P. A. Buxton Nat. Hist. Tsetse Flies xv. 642 Only 4 of the 19 developed an infection; they had received doses estimated to be 170, 284, 389, and 455 metacyclics. 1988Parasitology XCVI. 26 The repertoire of variant antigen types displayed by the metacyclics..is both limited and conserved. |