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21.
We found a new protein haponin (an HLDF-alike protein) in promyelocyte HL-60 cells that is immunoreactive to polyclonal antibodies against HLDFbeta. Determination of the partial primary structure of the protein allowed us to reveal an immunogenic peptide of haponin and, on the basis of the amino acid sequence of this peptide, the degenerate primers were synthesized, which enabled us to clone the full-size cDNA of haponin. The stable heterologous expression of this cDNA in E. coli cells (Rosetta strain) was obtained. Preparations of natural and recombinant proteins exhibited antigenic cross-reactivity to polyclonal antibodies against this peptide.  相似文献   
22.
Standard parameters of external respiration at the aerobic–anaerobic transition and above the anaerobic (ventilatory) threshold (AT) were studied in highly trained athletes during an incremental treadmill test. The efficiency of the adaptive response (AR) was inferred from changes in the heart rate and VO2gradients beyond the AT. Several AR types differing in the efficiency of the AT to the physical load were identified. The most efficient AR was associated with a decrease in the heart rate gradient and an increase in the VO2gradient above the AT. The least efficient AR was associated with an increase in the heart rate gradient and a decrease in the VO2gradient above the AT. The efficiency of the AR to cyclic muscular load varies daily in individual athletes.  相似文献   
23.
The binding of phosphatidylinositol-3,4,5-triphosphate to a protein with molecular mass of 45 kDa from rat olfactory epithelium (p45) was investigated using a model membrane system. Liposomes containing a mixture of phospholipids (phosphatidylethanolamine, phosphatidylcholine, and phosphatidylinositol-3,4,5-triphosphate) were used in the study. The binding of the protein to liposomes caused by its interaction with phosphatidylinositol-3,4,5-triphosphate was confirmed by cosedimentation and immunoblotting with chemiluminescent detection using monoclonal antibodies to the native protein p45.  相似文献   
24.
The distribution of temperature, salinity, phytoplankton, zooplankton, and nekton, including Pink Salmon and Chum Salmon, is analyzed based on the data from a complex survey conducted in the upper epipelagic zone of the northwestern Pacific Ocean in June–July 2009. An estimate of water transfer, plankton biomass (by size fractions and taxonomic groups), and biomass and abundance of nekton is made. The water circulation pattern was notable for the “compressed” state of the Western Subarctic Gyre. Copepods predominated in zooplankton (60.8% biomass), and Pacific Salmon dominated in the nekton. The ratio of the plankton biomass to the nekton biomass in various biostatistical areas varied from 23.9 to 195.1 (mean 46.7). It was found that the nekton biomass in the area of the spreading subarctic waters reaches its maximum in the summer months and that in the area of subtropical waters reaches its maximum in the fall. In the upper 30-meter layer, the biomass of fish and squid rose during the night to 2.92 million tons, or 1.6 times as much, due to mesopelagic migrants. The nekton communities of the upper epipelagic of the northwestern Pacific Ocean functioned normally, providing a high level of biological and fish productivity.  相似文献   
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The firing of "spontaneous" spikes is regarded as a result of mediator propagation to extrasynaptic receptors. Receptor-receptor interaction unites them in dimer and dimer clusters, which accept three conformational states under agonist action. There are two cooperative and potential dependent transitions between the states, where cluster accumulates or releases energy. The released energy can trigger a mechanism of endogenous (spontaneous) neuron firing in potentiation condition. These accumulating and triggering properties are absent in third (passive) conformational state, where gating charges immobilization reduces conformational mobility. The features of ionotropic, metabotropic and combined mediator action are discussed for different level of slow potential. Conformational effect depends on conformity of pattern space-temporal structure to geometric and functional features of metabotropic mediator sources in cluster environment. Each cluster appears to be adjusted for recognizing a certain vast set of afferent patterns. Number, structure and dimensionality of the recognized patterns are given by: 1) threshold of conformational transition, 2) allocation of synaptic and extrasynaptic mediator ejecting points in gap-hole environment of the receptive cluster 3) combinatorial connections of presynaptic cells with inhibit and excite synapses and 4) signal delays in presynaptic ways and neuropil. Numerous receptive clusters of soma-dendrite membrane are capable to write down information, to keep and accumulate it and to recover. Engram stored as passive/active conformational receptive cluster states is recovered in inversion by "spontaneous" neuronal activity. The original information may be recovered by reading via inhibit synapses.  相似文献   
27.
Molecular Biology - Alzheimer’s disease (AD) is the most common proteinopathy, which is accompanied by a steady decrease in the patient’s cognitive functions with a simultaneous...  相似文献   
28.
The chromosome number and DNA content in Euglena gracilis cell have been shown by the number of investigators to vary essentially under the influence of some environmental factors (low phosphate and acetate concentrations, density of culture, temperature, light/dark regime, streptomycin treatment). Variability in the nuclear DNA quantity is supposed to be an important peculiarity of the structure and functional activity of the genome of Euglena gracilis.  相似文献   
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Chars from the genus Salvelinus, inhabiting lakes and lake-river systems, belong to morphologically and ecologically different forms whose taxonomic status is under dispute. In the present work, we have examined genetic variation and divergence in various chars from the Kronotsky lake basin: the lacustrine chars (white, nose, and long-head) and Dolly Varden char Salvelinus malma. The study was conducted using analysis of allozyme and microsatellite loci, myogens, RAPD, and restriction analysis of two mtDNA segments. The estimates of heterozygoisty at allozyme and microsatellite loci were similar to the corresponding parameters in populations of northern Dolly Varden and Arctic char. Heterozygote deficit was recorded in both samples of individual forms, and in the combined sample of all chars from Kronotsky Lake. For both markers, appreciable genetic differentiation among the samples of different char forms was found, which was comparable to that among the spatially isolated populations of northern Dolly Varden. This result indicates reproductive isolation among the char forms examined. However, this isolation is not complete, because no fixed differences between the forms by any of the genetic systems analyzed was found. The genetic differentiation among different forms of lacustrine chars, which corresponds to the interpopulation rather than interspecies level, is thought to be explained by their comparatively recent divergence.  相似文献   
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