| 释义 |
▪ I. nucleoid, a. and n.|ˈnjuːklɪɔɪd|
[f. nucle-us + -oid.]
A. adj. Like a nucleus in form or appearance.
1855in Ogilvie Suppl. 1880Bastian Brain xxiii. 465 These are either mere nucleoid bodies or small angular cells. 1889Jrnl. R. Microsc. Soc. 429 (heading) Nucleus or nucleoid bodies of schizomycetes.
B. n.
†a. [a. G. nucleoïd (M. Lavdowsky 1893, in Zeitschr. für wiss. Mikrosk. X. 8).] (See quots.) Obs.
Arnold (Virchows Arch. für path. Anat. u. Physiol. (1896) CXLV. 22) took over the term from Lavdowsky.
1905Gould Dict. New Med. Terms 383/2 Nucleoid, a term used by Arnold to designate the substance in the red corpuscles formed from the original nucleus. It is finely granular or fibrillar and is surrounded by a substance which Arnold calls paraplasm. 1913O. C. Gruner Biol. Blood-Cells 361 Nucleoid. Syn.: nuclear rests, inclusion-body. (a) A precipitation effect of hæmoglobin; (b) if basic, a special appearance of the basophile cell membrane. 1928E. B. Krumbhaar in E. V. Cowdry Special Cytol. I. x. 307 In addition to the several bodies just mentioned, various artefacts can be produced [in erythrocytes] by standing, poor fixation, non-isotonic solutions, etc., termed ‘nucleoids’.
b. [a. G. nucleoid (coined independently in this sense by G. Piekarski 1937, in Arch. für Mikrobiol. VIII. 438).] An organelle in bacteria and viruses functionally analogous to the cell nucleus of higher organisms.
1938Biol. Abstr. XII. 1407/2 The author's [sc. G. Piekarski's] studies seem to show that the nucleoids which he observed in bacteria and sarcina are equivalent to cell nuclei. 1965Bacteriol. Rev. XXIX. 277/1 The genetic material in bacterial cells forms structures which are called nucleoids... Although from the very beginning there was no doubt that these structures are nuclei with respect to their function.., their simple architecture and morphological appearance, which distinguish them from the type of nucleus present in higher organisms..make a special term desirable. 1970Nature 31 Oct. 410/2 The RNA dependent activity resides in the nucleoid. 1971Ibid. 30 Apr. 568 (caption) Cell from culture of B[acillus] subtilis... Two chromosomes appear as tightly packed ‘nucleoids’. 1972Sci. Amer. Jan. 29/2 The virion of the Rous sarcoma virus consists of a lipid-containing envelope.., an inner membrane and a nucleoid, or core, that contains the viral RNA and certain proteins.
▪ II. nucleoid
var. nucloid. |