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1.
In 50 cardiac preparations of persons of various age (children, teenagers, adolescents, persons of mature and elderly age) distribution of various branches of the tendinous chordae (basic, marginal, commissural, rough zone) and level of their fixation to the ventricular surface of the right and left cusps of the atrioventricular valves have been studied. The tendinous chordae in direction from the apex of the papillary muscles towards the cusps of the atrioventricular valves are divided into the branches of the 2d--9th orders. Total quantity increase of the tendinous chordae is noted in the mature age, especially those of the 1st order in the left ventricle, and their decrease in the elderly age with an increase of the chordae of the 4th, 5th and 6th orders. Single chordae of the 8th and 9th orders can be found in elderly persons. Certain age specificities are revealed in fixation of various tendinous chordae to the cusps of the atrioventricular valves; they are surely connected with functional peculiarities of their different zones, that ensure air-tightness of the atrioventricular openings. There are quantitative differences of the tendinous chordae, fixed to certain cusps of the left (anterior) and right (anterior, posterior) atrioventricular valves; this is evidently connected with the role of the cusps mentioned in the mechanism of the valves closing.  相似文献   
2.
In chronic experiments on nine cats electrical stimulation of the posterior zones of the lateral hypothalamus led to reproduction of a conditioned food-getting reflex produced previously in response to clicks. During stimulation of the globus pallidus a food-getting reflex also appeared in 3 of 10 zones studied, but it did so only irregularly. In response to combined stimulation of the hypothalamus and these three zones of the globus pallidus facilitation of this reflex was observed: its intensity was increased and its latent period shortened. Stimulation of other areas of the globus pallidus inhibited the food getting reflex of hypothalamic origin on account of the intensification of purposeless motor responses. Stimulation of the globus pallidus evoked desynchronization of spontaneous hypothalamic electrical activity. After bilateral electrolytic destruction of the globus pallidus and its principal efferent pathway (the ansa lenticularis) no conditioned food-getting reflex was reproduced during hypothalamic stimulation. After pallidectomy the amplitude of the spontaneous waves and evoked potentials was reduced by a statistically significant degree in the hypothalamic zones tested. The results are evidence of the existence of regulatory functional influences of the globus pallidus on the lateral hypothalamus.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 6, No. 6, pp. 592–601, November–December, 1974.  相似文献   
3.
The role of the tube feet in locomotion of the ophiuranAmphipholis kochii Lütken is examined. During stepping movements the anterior tube feet attach themselves to the supporting surface and at the end of the step they detach themselves from it. The signal for detachment is deviation of the foot into the posterior (relative to the direction of motion) position. Because of this arrangement of the "stepping" mechanism of the tube feet the task of coordinating their activity with arm movements is greatly simplified. The feet "automatically" attach themselves to the support when the arm which carries them plays the role of motor; conversely, they detach themselves from the support when this arm moves forward. The CNS thus evidently does not participate in foot and arm movement coordination. It simply assigns the general direction of motion to all the feet and coordination takes place "automatically" as a result of the special properties of the "stepping" mechanism of individual feet.Institute of Oceanology, Academy of Sciences of the USSR, Moscow. Institute of Problems of Information Transmission, Academy of Sciences of the USSR, Moscow. Moscow State University. Translated from Neirofiziologiya, Vol. 8, No. 6, pp. 633–639, November–December, 1976.  相似文献   
4.
During movement of the ophiuranAmphipholis kochii Lutken, any one of its arms can point forward and, consequently, any arm can perform different functions. The arm, when separated from the ophiuran together with the adjacent part of the nerve ring, is capable of complex motor acts, including locomotion. Division of the nerve ring in the ophiuran disturbs coordination of the arms. The results of experiments in which one or more arms were amputated showed that the choice of leading arm and of method of locomotion depends mainly on afferent impulses received from the arms. The results indicate that the neural centers of individual arms possess relative autonomy. Coordinated working of the centers is achieved through their interaction. This interaction ensures the distribution of functions between the arms in accordance with the motor task to be undertaken and coordinates the activity of the arms in time. The dominant role in the distribution of functions between the arms is played by the center of the leading arm, which controls the activity of at least the adjacent centers.Institute of Oceanology, Academy of Sciences of the USSR, Moscow. Institute of Problems in Information Transmission, Academy of Sciences of the USSR, Moscow. Moscow State University. Translated from Neriofiziologiya, Vol. 8, No. 5, pp. 529–537, September–October, 1976.  相似文献   
5.
In the summer of 1986 the epidemic, whose etiological agents were influenza viruses A (H1N1) and respiratory syncytial virus, was registered among the population of Novoshakhtinsk. In a number of mines 15.3-16.7% of the employees were affected. Influenza viruses A (H1N1) proved to be closely related in their antigenic and biological properties to viruses isolated in the USSR in March-June 1986, as well as to viruses A (H1N1), the etiological agents of the epidemic which developed in the USSR in October-December 1986.  相似文献   
6.
Russian Journal of Genetics - The present article reviews the rapidly growing body of research on the role of mitochondrial DNA (mtDNA) in the realization of individual risk of Parkinson’s...  相似文献   
7.
The influence of immunoregulatory cytokines IL-2, IL-7, and IL-15 on the activation, proliferation, and apoptosis of different subpopulations of an immune memory T-cell (CD45RO+) in healthy donors were investigated. It was demonstrated that rIL-2 equally affected both the activation and proliferation of CD4+ and CD8+ subpopulations of memory T-cells in vitro. High concentrations of rIL-2 increased the number of CD8+ memory cells expressing apoptotic marker CD95. Effect of rIL-7 and rIL-15 on the activation and proliferation of cytotoxic CD8+ memory cells in vitro was different. CD4+ memory lymphocytes exhibited relative resistance to activation and proliferation by rIL-7 and rIL-15 compared to rIL-2. This can provide them with relative resistance to apoptosis, as well as create the necessary conditions for accelerated implementation of their functional capacity in the development of a secondary immune response.  相似文献   
8.
The morphology and immunological phenotype of plastic-adherent cells from human colostrum were studied in an in vitro short-term culture (6–7 days) using antibodies to CD3, CD31, CD34, CD45, CD68, vimentin, and osteocalcin. In 20% of the analyzed cultural flasks, nearly equal proportion of fibroblast-like cells and rounded cells was observed. In the 80% of the flasks, cells of regular shape were detected with the presence of single fibroblasts. The diameter of flattened cells ranged from 10 to 100 μm. All plastic-adherent cells did not express CD3 and showed weak binding (w) to the antibodies against CD31, CD34, and CD45. At the same time, we identified adherent cells that readily bound the antibodies against CD68, vimentin, and osteocalcin. According to the literature data, the CD68 + CD3CD31wCD34wCD45w immunological phenotype of the majority of the adherent cells from the colostrum allows them to be classified as monocytes/macrophages. High expression of stromal antigens—vimentin and osteocalcin—in 40–45% of the adherent cells in the culturing medium lacking any osteogenic supplements (β-glycerophosphate, ascorbic acid, and dexamethason) implies the presence of osteoblasts in the colostrum, which differentiate from mesenchymal stem cells under the action of humoral factors contained in breast milk.  相似文献   
9.
Chromophore substrates Dnp-Ala-Glu-Phe-Ala-Arg-NH2 and Dnp-Ala-Ala-Phe-Nle-Ala-Arg-NH2 of aspartic proteases were synthesized by a combination of chemical and enzymic methods. The kinetic parameters of their hydrolysis with pepsin, aspergyllopepsin, and chymosin were determined. The introduction of Nle in the P1' position gives stable enzyme-substrate complexes with pepsin and chymosin. A Glu residue at the P2 position contributes significantly to an increase in kcat for the chymosin hydrolysis.  相似文献   
10.
Interaction of alpha-tocopherol and 1,4-dihydropyridine with endoplasmic reticulum membranes and model systems, human serum albumin and phospholipid bilayer, was studied using the microcalorimetry and fluorescent probes procedures. Dependence of microviscosity changes in the endoplasmic reticulum membranes on the place of antioxidants localization (protein structures or phospholipid phase) was shown. Increase of membrane structuralization under the influence of 1,4-dihydropyridines blocked their antioxidant action in spontaneous and induced lipid peroxidation.  相似文献   
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