| 释义 |
parabasal, a. (n.)|pærəˈbeɪsəl|
[para-1.]
1. Zool.
a. In Crinoids: Situated next to and articulated with a basal plate.
b. n. (also in mod.L. form parabasāle, pl. -ālia). A parabasal joint.
1872Nicholson Palæont. 125 In some cases the ‘basals’ are succeeded by a second row or cycle of plates..which are sometimes regarded as something special, and are termed the ‘parabasals’ or ‘sub-radials’. 1877Huxley Anat. Inv. Anim. ix. 593 A calyx supported on a stem, and composed of five basalia, five parabasalia, and five radialia.
2. Zool. [in this sense a. G. parabasal (C. Janicki 1911, in Biol. Centralbl. XXXI. 321).] Applied to the kinetoplast (sense a) of protozoa; chiefly in parabasal body. Also ellipt.
1912E. A. Minchin Introd. Study Protozoa vi. 89 The ring of blepharoplasts in Lophomonas is supported on the edge of a membranous structure,..which in its turn is surrounded by a peculiar striated body, the ‘collar’ of Grassi, or ‘parabasal apparatus’ of Janicki. 1924Hegner & Taliaferro Human Protozool. v. 127 Most of the members of the genus [Trypanosoma] are characterized by the possession of a more or less spindle-shaped body, a central nucleus, and a spherical or rod-shaped parabasal body, with which is closely associated a small blepharoplast and a flagellum. 1925, etc. [see kinetoplast]. 1973K. G. Grell Protozool. 17 Trichomonads have only a single, though occasionally branched, parabasal body which is anchored at the base of the flagella and can either wind about an axostyle or follow a straight course to the posterior end.
3. Med. Applied to cells from the layers of stratified epithelium just above the deepest (basal) layer of cells.
1948G. N. Papanicolaou et al. Epithelia of Woman's Reproductive Organs ix. 38 The parabasal postpartum cells..show a greater variety in size and form, somewhat larger nuclei, extensive vacuolization, and a tendency to congregate into larger groups. 1960Obstetr. & Gynecol. XVI. 407/2 Deep in the layers of the epithelia are the parabasal cells, which cover the basal germinal layer of cells and are characterized by dense, thick cytoplasm with vesicular nuclei. 1972Acta Cytologica XVI. 382/2 The presence [in amniotic fluid] of parabasal cells in excess of 70 per cent suggests a fetal weight of less than 500 gms. |