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1.
The possibility of obtaining low-molecular-weight heparins using a chitinolytic enzymatic complex immobilized on Silochrom has been demonstrated. The optimal conditions of this process (sodium acetate buffer, pH 7.0–7.5; temperature, 40–45°C; and duration of hydrolysis, 3 h) were determined. Depending on the ratio between heparin and the immobilized enzymatic complex, samples with molecular weights varying from 1.7 to 4.7 kDa, were obtained. These complexes inhibited factor Xa 2.0–3.7 times more effectively than the original heparin.  相似文献   
2.
New microbial genomes are sequenced at a high pace, allowing insight into the genetics of not only cultured microbes, but a wide range of metagenomic collections such as the human microbiome. To understand the deluge of genomic data we face, computational approaches for gene functional annotation are invaluable. We introduce a novel model for computational annotation that refines two established concepts: annotation based on homology and annotation based on phyletic profiling. The phyletic profiling-based model that includes both inferred orthologs and paralogs—homologs separated by a speciation and a duplication event, respectively—provides more annotations at the same average Precision than the model that includes only inferred orthologs. For experimental validation, we selected 38 poorly annotated Escherichia coli genes for which the model assigned one of three GO terms with high confidence: involvement in DNA repair, protein translation, or cell wall synthesis. Results of antibiotic stress survival assays on E. coli knockout mutants showed high agreement with our model''s estimates of accuracy: out of 38 predictions obtained at the reported Precision of 60%, we confirmed 25 predictions, indicating that our confidence estimates can be used to make informed decisions on experimental validation. Our work will contribute to making experimental validation of computational predictions more approachable, both in cost and time. Our predictions for 998 prokaryotic genomes include ∼400000 specific annotations with the estimated Precision of 90%, ∼19000 of which are highly specific—e.g. “penicillin binding,” “tRNA aminoacylation for protein translation,” or “pathogenesis”—and are freely available at http://gorbi.irb.hr/.  相似文献   
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Plasma Physics Reports - Inactivation of spore microorganisms on a dielectric surface by a dielectric barrier discharge with plane electrodes was studied experimentally. It is shown that, at an...  相似文献   
5.
Panov  V. P.  Safonova  S. S.  Baidarov  I. V. 《Biology Bulletin》2022,49(5):498-511
Biology Bulletin - The features of the structural adaptive changes in the somatic muscles of rainbow trout are presented at various stages of early post-hatching ontogenesis. The development of the...  相似文献   
6.
Panov  V. P.  Falii  S. S.  Orlov  A. M.  Artemenkov  D. V. 《Journal of Ichthyology》2019,59(6):928-937
Journal of Ichthyology - The morphological and functional characteristics of the somatic musculature’s histological structure have been studied for three species of deep-sea fish from the...  相似文献   
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During a period of twenty years, the von Willebrand factor (VWf) biological activity was evaluated in 805 patients with vein thrombosis, diabetes mellitus, chronic renal failure and ischemic heart disease. The examined patients were 168 with vein thrombosis, 129 with diabetes mellitus, 412 with chronic renal failure (CRF), and 96 with ischemic heart disease. The biological activity was also determined in 104 haemodialysis patients using four different haemodialytic membranes: 30 on cuprophan membrane, 30 on polymethylmetacrylate membrane (PMMA), 24 on hemophane and 20 patients on polysulphone (PS) membrane. In 42 patients with arterio-venous fistula prone to thrombosis, the biological activity of the von Willebrand Factor was 178% in comparison to 106% in the control group. The biological activity of VWF was increased in patients with vein thrombosis (p < 0.02), in patients with diabetes mellitus (p < 0.01), CRF (p < 0.05), and in patients with ischemic heart disease (p < 0.01). The highest biological activity was found in patients on PMMA (p < 0.001), then cuprophan (p < 0.05) and hemophane membrane (p < 0.01), while the lowest increase of its concentration was noticed in patients on PS without statistical significance. In arteriovenous fistula prone to thrombosis patients biological activity of the von Willebrand Factor was significantly increased (p < 0.01). Our investigations show the importance of VWF as a marker of endothelial disfunction, a possible predictor of A-V fistula thrombosis, and a possible marker of haemodialysis membranes biocompatibility.  相似文献   
9.
Kazakov  V. N.  Panova  T. I.  Panov  Yu. E. 《Neurophysiology》2002,34(5):349-365
Using radioimmune techniques, we studied in detail the concentrations of -endorphin (-En), met- and leu-enkephalins (mE and lE, respectively), and substance P (SP) in a number of structures of the brainstem and forebrain of the cat. According to the proposed concept, these structures comprise the noci- and antinociceptive brain systems (NS and ANS). The above indices were measured in intact animals and in animals after nociceptive electrocutaneous stimulation (NECS) of the limb, stimulation of the ventrolateral zone of the midbrain central gray (vl SGC, a nociceptive midbrain structure), stimulation of the dorsolateral part of the above region and dorsal raphe nucleus (dl SGC and Rd, antinociceptive midbrain structures), and after combined stimulations (NECS preceded by conditioning stimulation of one of the above midbrain zones). We found that in the norm maximum SP concentrations were observed in the NS structures, while those of -En and mE were the highest in the hypothalamic nuclei belonging to the ANS and in its midbrain centers (dl SGC and Rd). Nociceptive ECS, stimulations of the studied midbrain zones, and combinations of these stimulations could result in specific and, in some cases, very significant (by an order of magnitude and more) shifts in the concentrations of the mentioned neuropeptides in the studied set of the central structures. After NECS and its combination with vl SGC stimulation, SP concentrations in the NS structures considerably increased, while -En and mE concentrations in the ANS components dropped. Stimulations of the dl SGC and Rd were accompanied by increases in the mE and -En levels and simultaneous drops in the SP concentrations in the ANS components; reciprocate shifts were observed within the NS. Changes in the lE level, which were related to the influences used, were less specific and mostly appeared as increases in this index in the structures of both the NS and ANS. Combinations of NECS with conditioning stimulations of the vl SGC, dl SGC, or Rd demonstrated that the latter exert significant modulatory effects on the NECS-induced shifts in the concentrations of the studied neuropeptides. Considering the obtained data, a hypothetical scheme of neuropeptide organization of the cerebral NS and ANS has been proposed. In the examined brain structures, there are neuronal populations belonging to the two main neurochemical systems. One of them is SP-ergic, while another consists of mE- and -En-ergic neurons; these systems are in antagonistic relations. Changes in the levels of mE and -En always induce the attended opposite shifts in the SP levels, and vice versa. The lE-ergic neuronal populations, which co-exist with the above neurochemical systems, are relatively nonspecifically activated by either (noci- and antinociceptive) drives, but, according to the pattern of its responses, the lE-ergic system is closer to the SP-ergic one. It is supposed that pain signals, when coming to the vl SGC, activate SP- and lE-ergic neuronal populations; later on, the posterior and lateral hypothalamic nuclei and preoptic region are involved in the transmission of the above signals. When released by the corresponding neuronal populations in the vl SGC, lE activates the key ANS structures (dl SGC and Rd), and the latter, in turn, activate other components of this system, which form its ascending compartment (ventromedial, dorsomedial, and paraventricular hypothalamic nuclei, septum, basolateral amygdala, hippocampal fields 3 and 4, and cingular cortex). In the ANS,-En and mE function as transmitters.  相似文献   
10.
A comparative analysis of the strategy of countermeasures aimed at reducing exposure doses to the rural population is presented. The effectiveness of the proposed system of countermeasures assessed by criteria such as reduction factor of exposure doses and cost of averted doses. Costs of countermeasures in the rural settlements located in the affected zone are calculated for a long term after the Chernobyl NPP accident.  相似文献   
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