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The nerve endings in the intramural ganglia of the rat's heart are connected by synaptic and non-synaptic junctions with the dendrites and neuron bodies. Peri-membrane indurations of synaptic complexes may look relatively symmetrical or asymmetrical depending on the orientation of the section in relation to the elements of the Akert's presynaptic lattice. In non-synaptic junctions the indurations are symmetrical, but the presynaptic one may be more complicated in its structure. The synaptic complexes are disposed in the field of synaptic dilatations of axons and in the sites of interlacing thin "preterminal" parts of axons with dendrites. They connect preganglionic fibres with dendrites, neuron bodies and with the filamentous and fungiform thorns.  相似文献   
123.
A model consisting of two blocks (equations) was proposed for the analytical study of the biosphere-climate system over great periods of time. The first equation describes the balance of carbon dioxide in the atmosphere and represents the biological block of the model. The second equation is the equation of the energy balance or the physical block of the system. The model is based on the most general conceptions of living matter and the evolution process. A possible interpretation of some events and phenomena in the earth history in terms of the model is given.  相似文献   
124.
Dipyridamole, 2,6-bis(diethanolamino)-4,8-dipiperidinopyrimido(5, 4-d)pyrimidine, is employed in clinical practice as a vasodilator. It can also inhibit a specific membrane protein (glycoprotein P) which pumps anticancer drugs out of tumor cells. Dipyridamole (10-4 M) markedly slows down the kinetics of the electrogenic phase of the photoelectric response in Rhodobacter sphaeroides chromatophores. This phase is due to proton transfer from the external medium to the secondary quinone acceptor in the reaction center. In purple membranes of bacterium Halobacterium salinarium containing bacteriorhodopsin dipyridamole (in its charged state) significantly slowed the kinetics of proton transfer from the primary donor, Asp-96 (in membranes from bacteria of wild type), or from the external medium (in D96N mutant) to the Schiff base. It is suggested that dipyridamole can influence the structural-dynamic state of membrane proteins including modification of the structure of their hydrogen bonds involved in proton-transport processes.  相似文献   
125.
Catalytic antibodies (abzymes) induced by stable transition-state analogs   总被引:2,自引:0,他引:2  
This review deals with recent advances in the generation of catalytic antibodies by the immunization of animals with stable transition-state analogs. Characteristic features in the functioning of such abzymes are considered in comparison with traditional enzymes.  相似文献   
126.
The frequencies of translocations and dicentrics detected by "chromosome painting" in lymphocytes were estimated in 115 healthy donors and in 273 people exposed to uncontrolled irradiation at low doses 1-4 years ago. Age responses of both types of exchanges at the age range from 3 to 85 years fit to quadratic model. The frequency of translocations grew faster with age than the frequency of dicentrics. The yields of stable exchanges in exposed people was significantly higher than those in control donors of corresponding ages.  相似文献   
127.
Taking into account disturbances in the functioning of the immune system in atopic dermatitis (AD) and the potentiating role of staphylococcal and other infections, the possibility of the optimization of the therapy of AD with the use of preparations having immunomodulating action and immunogenic activity is proposed. In the complex therapy of AD in children we used polycomponent vaccine Immunovac B-4, introduced intranasally and orally. Under the influence of immunotherapy the clinical characteristics of the patients had pronounced positive dynamics. A considerable decrease in the spread of the process, the degree of its severity and subjective symptoms was noted shortly after the course of vaccine treatment. Simultaneously the SCORAD index dropped from 64.5 to 39.4. During the later period of observation further decrease in the severity of the course of AD in children occurred, and the minimal characteristics were observed in 6 months of observation. At that time the SCORAD index fell to 19.9 +/- 1.34. The volume of pharmacotherapy and the number of acute respiratory infections considerably decreased, the positive dynamics of the quantitative and qualitative composition of the intestinal microflora was noted. The prolonged immunotherapeutic effect of the polycomponent vaccine made it possible to recommend the vaccine for the optimization of the therapy of AD.  相似文献   
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129.
Visual acuity was measured in 140 3–9-year-old children using Landolt’s rins with a gap in one of four orientations. The influence of surrounding additional contours on the detection of orientation of rings of a minimal visible size was studied in the same children, depending on the distance between the rings and the surrounding. The latter consisted of four bands, located symmetrically with reference to the ring. Visual acuity increased with age, reaching the adult level by approximately seven years. A deterioration of the orientation recognition was detected in all children when the surrounding was close to a ring. The distance that caused a perception deterioration decreased with age, reaching the adult level by nine years. The obtained data are discussed from the viewpoint of a possible influence of individual visual areas formed during ontogeny on task performance.  相似文献   
130.
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