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11.
E D Gol'dberg G V Karpova L A Kolmogorova O L Voronova T I Fomina E A Andreeva 《Antibiotiki i khimioterapii͡a》1991,36(11):30-34
Epirubicin (pharmorubicin, India), an antitumor antibiotic of the anthracycline group, was studied in regard to its effect on peripheral blood, bone marrow and lymphoid organs (the thymus and spleen) of CBA mice after its intraperitoneal administration in a single dose equal to the MIC (7.8 mg/kg) and in a course dose (1/5 of the MIC 5 times a day). The cytogenetic impairments induced by the cytostatic were estimated on metaphase plates with the bone marrow specimens and by counting the peripheral blood erythrocytes with micronuclei (the micronuclear test). It was shown that epirubicin induced cytogenetic disturbances in the hemopoietic cells within the first 72 hours. The antibiotic had a marked reversible effect on the erythroid population and lymphoid tissues and a moderate toxic action on the granulocyte population. The antibiotic did not affect thrombocytopoiesis. The single administrations had a more pronounced and prolonged myelotoxic and lymphotropic effect. 相似文献
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V. N. Kazakov E. D. Krakhotkina P. Ya. Kravtsov V. F. Andreeva T. G. Kebkalo 《Neurophysiology》1990,22(4):315-320
Retrograde horseradish peroxidase axonal transport techniques were used for quantifying the spatial organization of cortical neurons constituting descending fiber systems running to hypothalamic structures. This revealed the diversity of corticohypothalamic connections: the prefrontal cortex exerts a more marked effect on the hypothalamus than other cortical regions of the limbic system. Corticohypothalamic cells form neuronal groups at different frontal levels of the prefrontal cortex and cingulate gyrus; shape and orientation of cell groups are determined by the topography of predominant axonal systems travelling to the hypothalamus. Various forms of cell combinations occur within neuronal populations. Neuronal arrays may underlie the organizational principle of direct corticohypothalamic pathways.A. M. Gor'kii Medical Institute, Ministry of Public Health of the Ukrainian SSR, Donetsk. Translated from Neirofiziologiya, Vol. 22, No. 4, pp. 435–441, June–July, 1990. 相似文献
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34Fusarium graminearum Schw isolates produced 4-deoxynivalenol to form significant amounts of 4, 7 — dideoxynivalenol and lesser amounts of 4 — deoxynivalenol monoacetates on grain substratesin vitro. This is the first report on the capability a large group of naturally occurring isolates to produce 4,7-dideoxynivalenol. The average levels of 4,7-dideoxynivalenol on rice, corn, barley, and wheat as a substrate were respectively 26.8, 14.0, 12.8, and 10.5% of the level of 4-deoxynivalenol. 4, 7 — dideoxynivalenol was present in all examined naturally contaminated wheat kernel samples at levels of 1.7 to 7.9% of the level of 4-deoxynivalenol. These findings suggest that more attention should be given to the occurrence of 4,7-dideoxynivalenol in cereals. 相似文献
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Polarization of fluorescently labeled myosin subfragment-1 fully or partially decorating muscle fibers and myofibrils. 总被引:1,自引:1,他引:0
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Fluorescently labeled myosin heads (S1) were added to muscle fibers and myofibrils at various concentrations. The orientation of the absorption dipole of the dye with respect to the axis of F-actin was calculated from polarization of fluorescence which was measured by a novel method from video images of muscle. In this method light emitted from muscle was split by a birefringent crystal into two nonoverlapping images: the first image was created with light polarized in the direction parallel to muscle axis, and the second image was created with light polarized in the direction perpendicular to muscle axis. Images were recorded by high-sensitivity video camera and polarization was calculated from the relative intensity of both images. The method allows measurement of the fluorescence polarization from single myofibril irrigated with low concentrations of S1 labeled with dye. Orientation was also measured by fluorescence-detected linear dichroism. The orientation was different when muscle was irrigated with high concentration of S1 (molar ratio S1:actin in the I bands equal to 1) then when it was irrigated with low concentration of S1 (molar ratio S1:actin in the I bands equal to 0.32). The results support our earlier proposal that S1 could form two different rigor complexes with F-actin depending on the molar ratio of S1:actin. 相似文献
16.
Variation in the ribosomal internal transcribed spacers (ITS1 and ITS2) among eight taxa of the Mimulus guttatus species complex 总被引:1,自引:0,他引:1
The internal transcribed spacer region (ITS1 and ITS2) of the 18S-25S
nuclear ribosomal DNA sequence and the intervening 5.8S region were
sequenced from three individuals in each of eight taxa of the Mimulus
guttatus species complex. Three discrete variants, or "types," of ITS
sequences were found, among which 30%-40% of sites differed, compared with
1%-2% within types. Dot plots indicate that these types were not related by
conspicuous rearrangements or inversions. More than one ITS type was often
found in the same taxon, and two of three ITS types span species
boundaries, indicating their presence prior to speciation. These ITS
sequences showed essentially no positional homology with the nearest
sequenced relative, tomato. In contrast, the 5.8S region was relatively
unvaried, with 8 of 162 sites varied in the sample among all eight taxa.
The phylogeny inferred by the most common ITS sequence type, rooted by the
two other ITS types, agreed with isozymes in showing the distinctness of M.
nudatus, M. laciniatus, and M. tilingii from the other five taxa.
相似文献
17.
Today, the search for new energy sources continues unabated throughout the North. At the same time, scientists are increasingly concerned over the degradation of the Arctic and sub-Arctic environment stemming from fossil fuel and other large-scale energy projects already underway. Similar apprehensions are expressed by indigenous peoples who have often suffered from the impact of such development. While the most dramatic evidence of environmental devastation and social disruption is found in the Russian North, serious problems are by no means confined to that area alone. Nor are these negative effects necessarily limited to the borders of the country in which they originated. Indeed, the deleterious environmental impact of our global industrial economy has become sufficiently profound that social analysts are beginning to ask whether development strategies that cause such harm to the Arctic and sub-Arctic region should continue; and if not, what should replace them. This article addresses these issues as they relate to questions of sustainability, equity, political empowerment, and human rights in northwest Siberia and northern North America. 相似文献
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Experiments on bats using the technique of anterograde and retrograde horseradish peroxidase transport showed that neurons of the superior olivary complex and inferior colliculus responding specifically to amplitude-modulated ultrasonic stimuli have projections to the oral reticular nucleus of the pons. Neurons of this part of the reticular formation respond to presentation of amplitude-modulated stimuli by a synchronization response, like neurons of specific auditory formations. It is concluded that the flow of action potentials from neurons coding amplitude modulation of the stimulus at the superio olivary and inferior collicular levels spreads outside the auditory system.A. A. Ukhtomskii Physiological Research Institute. A. A. Zhdanov Leningrad State University. Translated from Neirofiziologiya, Vol. 16, No. 6, pp. 800–807, November–December, 1984. 相似文献