| 释义 |
hypochromic, a.|haɪpəʊˈkrəʊmɪk|
[f. hypo- 4 + Gr. χρῶµ-α colour + -ic.]
1. Med. Characterized by or designating a colour index less than one, or red blood cells that contain less hæmoglobin than normal and show an increased central pallor; esp. in hypochromic anæmia.
1924T. R. Waugh in Can. Med. Assoc. Jrnl. XLVII. 114/1 Such anaemias consequently show considerable variation in their blood pictures. If the response is slight..the red cells are small, and stain poorly,..and the color index is low. This type is therefore hypochromic. 1935Whitby & Britton Disorders of Blood vi. 126 Hypochromic anæmia, especially, is more often a symptom than a disease. 1958G. C. de Gruchy Clin. Haematol. ii. 42 In the tail of the film the cells are often distorted and flattened, and hypochromic cells may actually appear normochromic. 1966J. W. Linman Princ. Hematol. v. 157 Most hypochromic anemias are caused by iron lack.
2. Characterized by or exhibiting a decrease in the extent to which light (usually, ultra-violet radiation) is absorbed; chiefly in hypochromic effect.
1946Ann. Rep. Progr. Chem. XLII. 118 For substituents attached to the carbonyl group, the effects are quite different, both λmax. and εmax. being usually decreased (hypso- and hypochromic effects). 1959Jrnl. Amer. Chem. Soc. LXXXI. 6003/1 In general the oxidation of a methylthio group to a methyl sulfone involves a hypsochromic shift of from 10 to 40 mµ... This hypsochromic shift usually is accompanied by a definite hypochromic effect. 1968[see hyperchromic a. 2].
Hence ˌhypochroˈmicity, the property of absorbing less (ultra-violet) light.
1958Nature 29 Nov. 1502/1 In view of the zero hyperchromicity of polyguanylic acids at alkaline pH's, the variation of hypochromicity with pH was examined for a number of derivatives. 1960D. Shugar in Chargaff & Davidson Nucleic Acids III. xxx. 59 When the extinction of a given oligonucleotide is lower than that of its constituent mononucleotides, it is ‘hypochromic’ or exhibits ‘hypochromicity’. |