| 释义 |
‖ theca|ˈθiːkə|
Pl. thecæ |ˈθiːsiː|.
[L., ad. Gr. θήκη case, cover.]
1. A receptacle, a cell; spec. (Eccl.) = burse 1 b.
1662J. Bargrave Pope Alex. VII (1867) 121 Some of these underground streets were for their burials,..the corps were..immuralld in thecas, or, as it were, in hollow shelves dug into the wall. 1682Lister tr. Gœdart's Insects 95 In this Nest they [Bees] make a Theca, or small Cell... Every Bee lays 9. little Worms in this Theca, or Cell.
2. Bot. A part of a plant serving as a receptacle; a sac, cell, or capsule; spec. (a) an anther cell, containing pollen; (b) a vessel containing spores in various cryptogamous plants, as the capsule of a moss, the sporangium of a fern, or the fructification in certain lichens.
1676Grew Anat. Flowers ii. iii. §9 These Parts [anthers] are all hollow; each being the Theca or Case of a great many extream small Particles. 1829Loudon Encycl. Pl. (1836) 874 Musci... Thecæ many-seeded, solitary, furnished with an operculum and columella. Ibid. Gloss., Thecæ, the cases that contain the sporules of Cryptogamic plants. 1830Lindley Nat. Syst. Bot. 307 Sporules, which are enclosed in particular cases called thecæ. 1880Gray Struct. Bot. vi. §6 (ed. 6) 251 The best technical name for anther-sac is that of Theca. 1897Willis Flower. Pl. & F. I. 77 The anther has typically two main lobes or thecae.
3. Zool. and Anat. A case or sheath enclosing some organ or part: as
(a) the horny case of an insect pupa; (b) the loose sheath investing the spinal cord; (c) one of the fibrous sheaths in which the digital tendons glide; (d) the sheath of the proboscis of dipterous insects; (e) a cup-like or tubular structure in corals, containing a polyp.
1665–6Phil. Trans. I. 89 It becomes a Papilio or Butter⁓fly, in the Theca or Case. 1670Ibid. V. 2099 Some of these Maggots I took out of their Theca or bagg. 1807Med. Jrnl. XVII. 308 The theca or sheath which encloses the femoral artery, nerve and vein. 1826Kirby & Sp. Entomol. III. xxxiv. 467 In all [mouths of Dipterous insects], the theca or sheath is present. 1840E. Wilson Anat. Vade-M. (1851) 239 In the thecæ of the fingers several small tendinous fasciculi are generally found. 1875Huxley in Encycl. Brit. I. 130/2 In the simple aporose corals the calcification of the base and side walls of the body gives rise to the cup or theca. 1899Allbutt's Syst. Med. VII. 536 The water-cushion which surrounds the cord within the spinal theca.
b. In full theca folliculi. A layer of hormonally active cells enclosing a tertiary (vesicular) or a mature (Graafian) ovarian follicle, consisting of an inner, vascular layer (theca interna) and an outer, fibrous layer (theca externa). [So named in Ger. by C. E. von Baer (Über Entwickelungsgeschichte der Thiere (1837) II. iii. xv. 23).]
1857Dunglison Dict. Med. Sci. (rev. ed.) 400/1 Folliculi Graafiani, small spherical vesicles in the stroma of the ovary, which have at least two coats; the outer termed ovicapsule..and theca folliculi. 1859R. B. Todd Cycl. Anat. & Physiol. V. 551/1 The external or vascular coat [of the Graafian follicle]..constitutes the tunic of the ovisac of Barry, the tunica fibrosa, S. theca folliculi of Baer. 1929[see luteinized ppl. a.]. 1930Maximow & Bloom Text-bk. Histol. xxxii. 640 There is no sharp limit between the two layers of the theca or between the theca externa and the stroma. 1966McGraw-Hill Encycl. Sci. & Technol. XI. 474/1 A growing follicle has several layers of follicular cells, or granulosa cells.., and a surrounding capsule of connective tissue, the theca folliculi. 1978D. B. & E. Wilson Human Anat. xvi. 388/2 The inner layer is the theca interna, which secretes the hormone estrogen into the vascular system.
4. Special Comb.: theca cell tumour Path., an œstrogen-secreting ovarian tumour that consists of cells resembling those of the theca folliculi and is sometimes malignant; = thecoma.
1937Amer. Jrnl. Obstetr. & Gynecol. XXXIV. 988 It was not until 1932 that the last member of this interesting group of tumors was reported by Loeffler and Priesel, to which they gave the name of ‘fibroma theca cellulare xanthomatodes ovarii’, more commonly known as the theca cell tumor. 1974Passmore & Robson Compan. Med. Stud. III. xxviii. 50/1 Luteinization of the cells of granulosa cell and theca cell tumours may occur.
Hence ˈthecal a., of, pertaining to, or of the nature of a theca; ˈthecate a., having a theca, sheathed.
1847R. Druitt Surg. Vade M. (ed. 4) 544 The tendinous whitlow, or thecal abscess. 1861J. R. Greene Man. Anim. Kingd., Cœlent. 160 A thecal corallum, in other Actinozoa, at length comes to be formed. 1876Tomes Dental Anat. 107 The tissue whence the dentine papillæ arise blends insensibly with that making up the substance of the thecal fold. 1877Huxley Anat. Inv. Anim. iii. 159 The thecal canals of the Millepores. 1891Cent. Dict., Thecate. |