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31.
The effect of different degrees of avitaminosis B6 in mice on the cytolytic activity of T lymphocytes, measured as the quantity of Na2Cr51O4 released from lysed target cells, was studied on a model of the primary immune response in a mixed lymphocyte culture in vitro. Keeping animals for 3 weeks on a diet without pyridoxine did not affect the ability of the lymphocytes to proliferate in vitro or their cytolytic activity. In animals receiving a diet without pyridoxine for 45 days the content of pyridoxal-5-phosphate in the spleen was 55% lower than in the control. Lymphocytes taken from these animals, when cultured in vitro, showed sharply weakened ability to incorporate [3H]thymidine into DNA in response to the alloantigen. The cytolytic activity of these lymphocytes also was reduced. The ability of different forms of pyridoxine to restore the functions of T lymphocytes, when disturbed by avitaminosis B6, was studied.Laboratory of Systemic Blood Diseases, Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Kraevskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 8, pp. 185–188, August, 1977.  相似文献   
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The ability for replication of vaccine avian pox viral strains FK and Dessau in cell clones, derived from the EBTr cell line, derived from embryonic bovine trachea, was studied. The derived seven cell clones showed different morphological characteristics and diverse sensitivity to both vaccine avian pox viral strains. Hence, the EBTr-derived cell clones could be used for cultivation, as well as for differentiation of vaccine avian pox viral strains. In addition, studies have been undertaken to elucidate the possible use of cultivated strains in these heterologous cell culture system's vaccine avian pox viral strains for biotechnology, as well as for solving problems, related to infection of people with avian viruses.  相似文献   
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A Hantavirus was isolated in Vero-E6 cells from lungs of a free living bank vole (Clethrionomys glareolus) captured in Turnhout, Province of Antwerp--Northern part of Belgium. With help of monoclonal antibodies the Belgian Hantavirus isolate could be clearly differentiated from Hantaan virus strain 76-118, Prospect Hill virus strain PH1 and SR11, a Hantavirus isolated from laboratory Wistar rat in Japan, but not from the nephropathia epidemica virus strain H?lln?s.  相似文献   
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Evoked neuron activity in slices of the medial septal area and its modulation by neuropeptides and monoamines was studied in two groups of ground squirrels – hibernating and awake animals. Electrical stimulation of the medial forebrain bundle evoked predominantly inhibitory effects of different durations. In addition, responses were seen consisting of resetting of the phase of background volleys to the stimulus after initial inhibition; there were also small numbers of short-latency single-spike responses. All the neuropeptides tested, which had been identified from the brains of hibernating animals, induced differentiated reversible effects consisting of modulation of responses; changes in evoked activity were seen significantly more often than shifts in spontaneous activity. The effects depended on the state of the animal. Thus, peptide TSKYR increased the duration of inhibition in hibernating ground squirrels but shortened inhibition in awake animals. Peptide TSKY, which had little effect in hibernating animals, increased the duration of inhibition in awake animals. Dipeptide DY, which decreased the duration of inhibition and increased the amplitude of the activatory components of responses in hibernating ground squirrels, had little effect in awake animals. The effects of noradrenaline and serotonin correlated to a large extent with their effects on spontaneous activity. It is suggested that endogenous substances are involved in creating the conditions required for increasing the latent excitability and reactivity of septal neurons during hibernation. This allows the medial septal area to function as a sentry post, allowing the receipt of signals and urgent arousal during hibernation.  相似文献   
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Primary culture of prostatic adenocarcinoma is obtained from surgical material after radical prostatectomy. Typing of the obtained culture with antibodies to vimentin and cytokeratins has shown that the proportion of basic cell components--stromal and epithelial--in vitro correlates with such in the initial tumor tissue. In cultivation in different media active migration and proliferation of all cell types in the presence of embryonal serum and suppression of the stromal component in the medium where the serum was replaced for bovine hypophysis extract were observed. A comparative immunohistochemical analysis registered a release into culture of alpha SMA-positive myofibroblasts and active expression of TGF beta-1 in the medium containing serum. Design of dynamic mixed cell systems may serve a convenient model for investigation of stromal-epithelial interactions and their changes in cancer progression.  相似文献   
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