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61.
Galactoglucomannans were isolated by selective precipitation from aqueous and alkaline extracts of endosperm and hulls of Cercis canadensis, a member of the family Fabaceae. Their monosaccharide composition (Man: Gal: Glu) was as follows: 10.4: 0.9: 1 (polysaccharide from the endosperm) and 4.5: 0.9: 1 (polysaccharide from the hulls). The identity of IR spectra was indicative of the commonness of their structure. Analysis of the structure of the galactoglucomannan from endosperm by 13C NMR spectroscopy showed that its main chain consisted of 1,4-beta-D-manno- and 1,4-beta-D-glucopyranose. Part of mannose residues in the chain were substituted at C6 with single residues of alpha-D-galactopyranose. Galactoglucomannans are located in different part of the seed and implement different functions.  相似文献   
62.
Galactoglucomannans were isolated by selective precipitation from aqueous and alkaline extracts of endosperm and hulls of Cercis canadensis, a member of the family Fabaceae. Their monosaccharide composition (Man : Gal : Glu) was as follows: 10.4 : 0.9 : 1 (polysaccharide from the endosperm) and 4.5 : 0.9 : 1 (polysaccharide from the hulls). The identity of IR spectra was indicative of the similarity of their structure. Analysis of the structure of the galactoglucomannan from endosperm by 13C NMR spectroscopy showed that its main chain consisted of 1,4--D-manno- and 1,4--D-glucopyranose. Part of the mannose residues in the chain were substituted at C6 with single residues of -D-galactopyranose. Galactoglucomannans are located in different parts of the seed and implement different functions.__________Translated from Prikladnaya Biokhimiya i Mikrobiologiya, Vol. 41, No. 3, 2005, pp. 324–329.Original Russian Text Copyright © 2005 by Mestechkina, Egorov, Anulov, Shcherbukhin.  相似文献   
63.
Physiological and methodological principles of the organization of physical training (PT) and its computerization during a space flight to Mars under the conditions of autonomous activity of the crew, including interaction with onboard medical systems, self-maintenance of health, preventive measures, diagnostic examinations, and, if necessary, treatment, are discussed. The conditions of unusually long-term autonomous space flights make the ground-based monitoring of the state of health of crew members substantially more difficult, which calls for computerization of the control over the crew members’ health, including prophylactic measures. The situation is further complicated because it is impossible to receive the necessary information from, and transmit it to, the spacecraft in a real-time mode or to quickly return the crew to Earth in case of an emergency. Under these conditions, physical prevention should be based on an onboard automated expert system ensuring the control over the activities of all crew members aimed at optimizing their psychophysical state. The problems of the control of training, including the use of an onboard automated expert system, are discussed.  相似文献   
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65.
Working memory is an emergent property of neuronal networks, but its cellular basis remains elusive. Recent data show that principal neurons of the entorhinal cortex display persistent firing at graded firing rates that can be shifted up or down in response to brief excitatory or inhibitory stimuli. Here, we present a model of a potential mechanism for graded firing. Our multicompartmental model provides stable plateau firing generated by a nonspecific calcium-sensitive cationic (CAN) current. Sustained firing is insensitive to small variations in Ca2+ concentration in a neutral zone. However, both high and low Ca2+ levels alter firing rates. Specifically, increases in persistent firing rate are triggered only during high levels of calcium, while decreases in rate occur in the presence of low levels of calcium. The model is consistent with detailed experimental observations and provides a mechanism for maintenance of memory-related activity in individual neurons.  相似文献   
66.
The third complementary determining region of the immunoglobulin heavy chain (CDR H3) is one of the more difficult structures to model due to genetic reasons. However, the conformation of proximal to beta-framework ("torso") part of the CDR H3 is very predictable. Current "CDR's canonical classes" theory is based on identifying the key positions, H94 and H101. We can determine the CDR H3 "torso" structure if arginine or lysine is present in the H94 position and/or aspartic acid in the H101 position. We target the case characterized by the absence of key residues in both the H94 and H101 positions. There has not been discussion on this case in the literature. 51 CDR H3 structures of this nature are analyzed and we established new sequence-structure rules. These rules contribute to more accurate modeling of the antibody's structure.  相似文献   
67.
Two new species of the genus Bioramix Bat. (tribe Platyscelidini) are described from China, Bioramix (Cardiobioramix) splendida sp. n. (Sichuan) and B. (Cardiobioramix) kabaki sp. n. (Gansu).  相似文献   
68.
This paper discusses an issue on the development of biophysical methods for biochip analysis. A scheme and construction of a biochip analyzer based on wide-field digital fluorescence microscopy are described. The analyzer is designed to register images of biological microchips labeled with fluorescent dyes. The device developed is useful for high-sensitive throughput recording analyses by biochips after interaction of immobilized probes with fluorescently labeled sample molecules as well as it provides the higher rate of the analysis compared to laser scanning devices. With this analyzer a scope where biological microchips can be applied becomes wider, the development of new protocols of the analyses is possible and standard analyses run faster with the use of biochips, the expenses for the analysis performance can be reduced.  相似文献   
69.
In this study we report that, in response to proteasome inhibition, the E3-Ubiquitin ligase TRIM50 localizes to and promotes the recruitment and aggregation of polyubiquitinated proteins to the aggresome. Using Hdac6-deficient mouse embryo fibroblasts (MEF) we show that this localization is mediated by the histone deacetylase 6, HDAC6. Whereas Trim50-deficient MEFs allow pinpointing that the TRIM50 ubiquitin-ligase regulates the clearance of polyubiquitinated proteins localized to the aggresome. Finally we demonstrate that TRIM50 colocalizes, interacts with and increases the level of p62, a multifunctional adaptor protein implicated in various cellular processes including the autophagy clearance of polyubiquitinated protein aggregates. We speculate that when the proteasome activity is impaired, TRIM50 fails to drive its substrates to the proteasome-mediated degradation, and promotes their storage in the aggresome for successive clearance.  相似文献   
70.
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