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This study was pursued on hybrid (CBA X C57Bl)F1 mice at the ages of 17 and 27 months irradiated at a dose of 4 Gy. It was shown that the postirradiation recovery of haemopoiesis in old mice was the same as in the young (2-3 month-old), and in some respects (for instance, granulocytic and erythroid cells of the bone marrow, and CFUc) the recovery was even more active exhibiting a period of a pronounced hyperregeneration.  相似文献   
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Cellular composition of the bone marrow, spleen and peripheral blood was studied after 6-hour immobilization on the back in experiments on 4 groups of (CBAxC57BL)F1 mice with varying degree of T lymphocyte deficiency (thymectomy, sham thymectomy, administration of antilymphocytic serum, B mice). The evidence obtained shows that the "lymphoid peak" recorded in the bone marrow during stress is likely to be formed at the expense of T and B lymphocyte migration from the peripheral lymphoid organs. The data have been also obtained, indicating that T lymphocytes migrating to the bone marrow during the first 6-9 hours after the exposure to stress may participate in granulocytopoiesis activation.  相似文献   
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Characteristics of a mutant of the yeast-like fungus Candida albicans with increased sensitivity to amphotericin B, levorin and nystatin is presented. Increased sensitivity to the polyens in the isolate must be associated with changes in the cell wall and/or with decreased total viability of the strain. The following factors were in favour of this: presence of significant amounts of pseudomycelial cells with thinner cell walls as compared to the yeast cells in the population of the mutant strain; a higher rate of potassium liberation from the cells of the mutant strain in the presence of amphotericin B; a lower growth rate of the mutant strain on solid and liquid media; an increased death rate of the cells in the intact culture of the mutant strain as compared to the initial strain; absence of changes in the absorption spectrum of sterols isolated from the cells of the mutant strain as compared to the initial culture.  相似文献   
5.
Lipopolysaccharide composition of tetracycline sensitive and resistant strains of E. coli was studied comparatively. It was shown that that resistance of E. coli to tetracycline was probably due to the differences in the lipopolysaccharide component composition of the outer membrane. On the basis of the activity comparison of the Mg2+- and Ca2+-activated ATP-ase of the membrane fraction of the tetracycline sensitive and resistance strains of E. coli it was concluded that the resistance development in the strains tested to tetracycline was not associated with the changes in the ATP-ase activity.  相似文献   
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Between 1971 and 1975, Fascioloides magna was found in 46 of 67 (69%) feral swine (Sus scrofa) in southern Texas. Flukes were recovered from swine in areas where F. magna commonly has been recovered from white-tailed deer and cattle. One to 12 flukes were recovered from each infected animal. Their presence was indicated by black hematin pigment on the liver and various other internal organs. Eggs were not detected in the gallbladder or feces of infected animals although mature flukes and eggs were recovered in the livers suggesting that, like cattle, feral swine can be infected but are aberrant hosts for the parasite and do not disseminate eggs.  相似文献   
7.
Evoked potentials to acoustic stimuli were recorded in the temporal cortical area, the medial geniculate body and the posterior lateral thalamic nucleus in acute experiments on anaesthetized cats. Section of the brachia of the inferior colliculi in an acute experiment resulted in the disappearance of potentials in the examined structures. A distinct correlation has been revealed between the recovery of evoked potentials in the cortico-thalamic auditory structures (in four to six weeks) and the possible elaboration of conditioned reactions within this time period after lesion of the inferior colliculi brachia. The involvement of the temporal area in the general brain activity appears to be one of the major conditions for the formation of new conditioned connections. Possible ways of restoration of afferent input to the temporal cortical area after lesion of the inferior colliculi brachia are discussed.  相似文献   
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Russian Journal of Genetics - Genetic diversity of diploid grass Ae. tauschii Coss (2n = 2x = 14, DD), the D-genome progenitor of common wheat, was assessed using fluorescence in situ hybridization...  相似文献   
10.
A complex of the heteropteran genera centering around Peribalus Mulsant et Rey and Holcostethus Fieber is considered. The genus Dryadocoris Kirkaldy reveals no relationship with the above genera and is believed to represent a separate clade of the family Pentatomidae. The genera Peribalus and Holcostethus are revised. The former includes three subgenera: Peribalus s. str. with two species, Asioperibalus subgen. n. (type species Cimex inclusus Dohrn) with six species, and Tianocoris subgen. n. (type species Holcostethus manifestus Kiritshenko) with two species. Holcostethus embraces two subgenera: Holcostethus s. str. and the monotypic Enigmocoris subgen. n. (type species H. fissiceps Horváth). Two new species are described: Peribalus tianshanicus sp. n. from the Tien Shan Mts. and P. przewalskii sp. n. from the northern part of China (Huan He River). P. capitatus Jakovlev and P. vernalis (Wolff) are downgraded to subspecies of P. strictus (F.). P. ovatus Jakovlev is synonymized with P. inclusus (Dohrn). Two new monotypic genera related to the revised complex of genera are established, Paraholcostethus gen. n. (type species Peribalus breviceps Horváth) and Himalayastethus gen. n. (type species H. pilosus sp. n. from Kashmir). A key to, and morphometric characters for all the taxa considered are provided. The key characters, including both male and female genitalia, are illustrated, and distributional maps are given.  相似文献   
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