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171.
The fourth larval stage (L4) of Coronocyclus labratus (Looss, 1900) Hartwich, 1986, one of the common species of the Cyathostominae found in equids, is identified and described.
The larvae found were identified as C. labratus by finding moulting forms possessing characters of both larval and adult stages. The larvae are similar to those of Cylicocyclus leptostomum (Kotlán, 1920) Foster, 1936, Cyathostomum catinatum Looss, 1900 and Cylicostephanus goldi (Boulenger, 1917) Lichtenfels, 1975. The buccal capsule (BC) wall of the L4 of Cylicocyclus leptostomum is thinner than that of Coronocyclus labratus, and the ring of the oesophageal funnel is comparatively less well developed. In C. labratus the dorsal tooth protrudes only slightly into the buccal cavity, and this larva possesses a characteristically elongate,
pyriform oesophagus. In Cyathostomum catinatum, the BC walls are thicker than in Coronocyclus labratus, and the dorsal tooth is more bluntly pointed. Sublateral teeth, if present, are bluntly pointed in the former species, but
usually absent or indistinct in C. labratus. Larvae of Cylicostephanus goldi differ from those of Coronocyclus labratus in the larger size of the BC. 相似文献
172.
Vitaliy O. Kaminskyy Maxim D. Lootsik Rostyslav S. Stoika 《Central European Journal of Biology》2006,1(1):2-15
The purpose of this study was to examine the relationship between the DNA intercalating characteristics and the DNA damaging
capacity of four alkaloids extracted from Chelidonium majus L, as well as their toxicity towards murine NK/Ly lymphoma cells. Chelerythrine, sanguinarine and coptisine were found to be
intercalated into the DNA isolated from NK/Ly cells, meanwhile, chelidonine exhibited no affinity to DNA. Sanguinarine exhibited
the greatest toxicity toward NK/Ly cells, and the toxicity of the other three decreased in descending order: chelerythrine,
coptisine and chelidonine. Chelerythrine and sanguinarine caused DNA damage, illustrated by the formation of comets of the
third class. Coptisine was less toxic than chelerythrine and sanguinarine, and affected the formation the same class of comets
in higher concentration. The quantity of comets induced by chelidonine were negligible, a finding consistent with its inability
to intercalate into DNA structure. The ability of four main alkaloids of Chelidonium majus L., to intercalate into DNA isolated from murine NK/Ly lymphoma cells, correlated with their ability to induce breaks in cellular
DNA and with their toxic effect towards those cells. 相似文献
173.
Sergey A. Mitchenko Eugeniy V. Khomutov Vitaliy V. Kovalenko Anatoliy F. Popov Irina P. Beletskaya 《Inorganica chimica acta》2001,320(1-2):31-37
Mechanical treatment of solid K2PtX6 (X=Cl, Br) salts under air or argon leads to the formation of paramagnetic platinum(III) complexes via homolytic cleavage of Pt---X bonds. Lewis acid sites (LASs) were also detected on the surface of mechanically activated K2PtCl6 using a paramagnetic probe. The latter species can be attributed to coordinatively unsaturated platinum(IV) complexes formed as a result of heterolysis of Pt---Cl bonds. Mechanical treatment of solid K2PtCl4, on the contrary, does not lead to homolytic Pt---Cl bond cleavage. In this case only heterolysis of the Pt---Cl bond takes place, leading to the formation of coordinatively unsaturated platinum(II) complexes. 相似文献