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71.
It was shown that gas hypoxic mixture containing O2 (10%) and N2 (90%) significantly decreases "intestinal" death of Wistar rats on the 5th day following irradiation and normalizes Na+,K+-ATPase activity of the small intestine mucosa plasma membranes. 相似文献
72.
Mikhaĭlov VM Kaminskaia EV Popov BV Kuzovatov SN Skripkina NS Kosikova GP Zaĭchik AM Grinchuk TM Nikol'skiĭ NN 《Tsitologiia》2010,52(10):853-857
The purpose of the study was the morphological and histochemical characteristics of differentiation of tumors developed after transplantation of GFP-positive mesenchymal bone-marrow stem cells (MSC) of transgenic mice C57BL/6 into M. quadriceps femoris of mdx mice. The tumors occurred only after transplantation of MSCs of 43-45th passages and did not arise after transplantation of MSCs of the 15th passage. No tumors developed also after transplantation of MSCs of 43-45th passages into muscle of C57BL/6 mice. The average weight of tumors appeared in 4 mdx mice studied was 1.3 +/- 0.5 g. All four tumors were classified as mesenchymomas because they originated from mesenchymal stem cells. Most of the periphery of the tumors was classified as fibrosarcomas with mitotic index 0.9 +/- 0.1%. The central parts of tumors had areas with epithelial like morphology of cells. Such cells showed positive reactivity for alcyan blue staining at pH 2.5, which indicated chondrocyte nature of the cells. No mitosis was observed in epithelial like cells. In the tumors, there were also areas with bone trabeculae containing megacaryocytes and foci of myeloid and erythrocyte hematopoiesis. There were also areas with neuronal and glial cells, and accumulations of adipocytes. One of the tumors was classified as a round cells sarcoma. The observed types of tumor cell differentiation in vivo were in accordance with described in literature types of MSCs differentiation after induction in vitro with special inductors. The spectrum of in vivo differentiation of transgenic GFP-positive MSCs after transplantation to mdx mice was broader than the spectrum of in vivo differentiation of transfected or transformed in vitro adult MSCs after transplantation to immunodeficient mice and mdx mice. 相似文献
73.
74.
Starokadomskiĭ PL 《Ukrainski? biokhimicheski? zhurnal》2005,77(4):14-29
Inteins are internal polypeptide sequences that are posttranslationally excised from a protein precursor by a self-catalyzed protein-splicing reaction. Most of inteins consist of N- and C-terminal protein splicing domain and central endonuclease domain. The endonuclease domain can initiate mobility of the intein gene, this process being named intein homing. This review is focused on the recent data about the structure and function of inteins. Main intein-mediated protein-engineering applications, such as protein purification, ligation and cyclization, new forms of biosensors, are presented. 相似文献
75.
Mamaĭ AV 《Biofizika》2005,50(4):743-747
A new generalized conception of an organism is given. Based on this conception, a new mathematical model of ontogenesis of an individual and the survival of the age cohort of population was proposed. By using real data on the dynamics of the survival of the age cohort of population, the model enables one to determine the parameters characterizing the relationship man-environment in the context of survival and calculate the dynamics (from birth to death) of the model variables of the state of the organism. 相似文献
76.
Parfenova VV Shimaraev MN Kostornova TIa Domysheva VM Levin LA Driukker VV Zhdanov AA Gnatovskiĭ RIu Tsekhanovskiĭ VV Logacheva NF 《Mikrobiologiia》2000,69(3):433-440
The vertical distribution of microorganisms during spring deep-water renewal in Lake Baikal was studied. The downward advection of trophogenic waters was found to create conditions for the extensive growth of microorganisms capable of decomposing and mineralizing organic carbon, nitrogen, and phosphorus in deep water layers. These processes occur annually at spring thermal bars near the underwater slope of Lake Baikal, whereas in its pelagic zone, the deep intrusions of waters rich in organic material are observed only in the years when enhanced deep-water renewal is accompanied by a high spring yield of phytoplankton. 相似文献
77.
The effect of ascorbic acid on suspensions of blood formic elements was studied by the ESR method. It was shown that incubation of a suspension of formic blood elements in the presence of ascorbic acid leads to the appearance of nitric oxide, which is produced by leukocytes and partially probably by thrombocytes. The formation of nitric oxide is evidenced by the appearance of nitrosyl complexes heme-NO. In this case, hemoglobin of erythrocytes serves as a natural trap for nitric oxide. 相似文献
78.
Shugalev NP Ol'shanskiĭ AS Hartmann G 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2002,52(6):750-755
After serotonergic lesion by administration of 5,7-dihydroxytryptamine into the dorsalis raphe nucleus, effects of neurotensin microinjections into the caudate nucleus and substantia nigra on rat behavior were compared. Serotonergic lesions resulted in motivated excitement of rats manifested as an increase in the number of intersignal motor reactions during realization and, particularly, extinction of thirst conditioned reflex. Neurotensin microinjections into the caudate nucleus facilitated extinction of the conditioned reflex both in operated and control rats, but such microinjection into the substantia nigra facilitated this process only in operated animals. Neurotensin did not change conditioned reflex realization in both groups of animals but decreased emotional excitement of rats in the "open field". The behavioral effects of neurotensin in operated rats are connected with normalization of motivational and emotional states of animals and may be explained by recovery of interaction between the dopamine- and serotonergic systems. It is suggested that the mechanisms of this normalizing effects of neurotensin at the levels of the caudate nucleus and substantia nigra are different and are associated preferentially with its action either on dopamine- or serotonergic structures. 相似文献
79.
Pankova NB Vetrilé LA Basharova LA Krupina NA Khlebnikova NN Rodina VI Kryzhanovskiĭ GN 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2003,53(2):199-207
In electrophysiological experiments in Wistar rats it was shown that preventive immunization of animals with bovine serum albumin conjugated with dopamine or 5-hydroxytryptamine or with bovine serum albumin alone partly protects against the development of experimental MPTP-induced depressive syndrome. Signs of depressive-like state such as decrease in REM-sleep latency and the development of epileptiform activity in caudate putamen were not observed in immunized animals, whereas REM-sleep proportion in the total sleep structure was increased. Changes in the spectral characteristics of brain electric activity and sleep structure during development of experimental MPTP-induced syndrome in immunized rats are antigen-specific and reflect the functional shifts in neurotransmitter systems, both in those which are the target of the immune action and those sensitive to alterations in the immune state of a body. 相似文献
80.