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261.
A factor reacting with SRBC and rabbit IgG was obtained under mild conditions from rat thymus and spleen.The isolation procedure includes incubation of thymocytes or splenocytes with IgG-cellulose adsorbent, destruction of cells, washing the adsorbent and elution of an adsorbed material at pH 2. This preparation as well as the purified substance previously obtained by affinity chromatography on IgG-cellulose columns were found to agglutinate both SRBC and autologous erythrocytes. Preincubation in 1% SDS leads to dissociation of the preparation into several components separated by gel electrophoresis.A probable relation of this structure to the rosette forming capacity of T-lymphocytes is discussed. 相似文献
262.
Dr. H. Boyko 《International journal of biometeorology》1958,2(1):87-90
Ohne Zusammenfassung 相似文献
263.
Boyko Neov Nikolai Spassov Latinka Hristova Peter Hristov Georgi Radoslavov 《Ecology and evolution》2021,11(6):2842
The origin and evolutionary history of the European bison Bison bonasus (wisent) have become clearer after several morphological, genomic, and paleogenomic studies in the last few years, but these paleogenomic studies have raised new questions about the evolution of the species. Here, we present additional information about the population diversity of the species based on the analysis of new subfossil Holocene remains from the Balkan Peninsula. Seven ancient samples excavated from caves in Western Stara Planina in Bulgaria were investigated by mitochondrial D‐loop (HVR1) sequence analysis. The samples were dated to 3,800 years BP by radiocarbon analysis. Additionally, a phylogenetic analysis was performed to investigate the genetic relationship among the investigated samples and all mitochondrial DNA sequences from the genus Bison available in GenBank. The results clustered with the sequences from the extinct Holocene South‐Eastern (Balkan) wisent to the fossil Alpine population from France, Austria, and Switzerland, but not with those from the recent Central European (North Sea) one and the now extinct Caucasian population.In conclusion, these data indicate that the Balkan wisent that existed in historical time represented a relict and probably an isolated population of the Late Pleistocene‐Holocene South‐Western mountainous population of the wisent. 相似文献
264.
Russian Journal of Marine Biology - Wnt and frizzled genes of 17 echinoderm species were studied by molecular and bioinformatics methods. As a result, it has been found that echinoderms have... 相似文献
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Paranoplocephala aquatica n. sp. is described from Arvicola terrestris and Ondatra zibethica (Rodentia, Cricetidae) in Bulgaria. The new species is characterised by a band-like strobila, a uterus forming a fine reticulate structure in the early stages of development, numerous testes (approximately 92) situated mainly aporally to the ovary in both the median and the aporal lateral fields, few testes positioned anterior to the ovary and genital ducts, the prominent asymmetrical situation of the female organs, the length of the vagina c. 0.65–0.68 of the length of the cirrus-sac, and the external seminal vesicle covered by a cellular sleeve. The new species is distinguished from P. ondatrae, P. macrocephala, P. dasymidis and P. sciuri. The specimens from O. zibethica reported as P. ondatrae by Tenora & Murai (1980) and as Aprostatandrya macrocephala by Spasskii et al. (1951) are believed to belong to P. aquatica. The type-series of P. ondatrae and P. macrocephala are redescribed and figured; metric data and an illustration of the holotype of P. sciuri are presented. The genus Paranoplocephala sensu Tenora et al. (1986) is regarded as a heterogeneous group because of the two patterns of uterine development in the species studied. Taxonomic criteria used for distinguishing the genera Andrya and Paranoplocephala, and some criteria applicable at the species level, are discussed. 相似文献