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21.
The main idea of the authors' paper is to propose the most reasonable way of actively introducing the digital principle into the traditional roentgenological section of radiation diagnosis. For this, a luminophore digital radiography system has been chosen. The authors of the paper give a full-scale assessment and appropriate recommendations for its use. The paper essentially discusses the entire complex of matters that permit assessment whether its sound use is possible in regional and municipal health care systems. This is both a section devoted to a dose load, by making a comparative assessment of luminophore radiography and "the green system" and a study of different clinical diseases (456 cases). In their study, the authors have applied an original principle in the formation of an image obtained and some other approaches in order to make a comprehensive assessment of this method. In the authors' opinion, luminophore radiography has a variety of advantages. Firstly, this technique can be simultaneously applied to several nondigital apparatuses, including those available in the ward and it shows a rather diagnostic effectiveness and economic profitability, yields a qualitative image of varying density tissues upon single exposure, and has some other capacities of the CR system as a digital technique. All this things considered, the authors consider that luminophore radiography may be one of the main ways of introducing a digital technique into the conventional roentgenological section of radiation diagnosis at the level of regional and municipal heath care systems. 相似文献
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Stepanova EV Koroleva OV Vasil'chenko LG Karapetian KN Landesman EO Iavmetdinov IS Kozlov IuP Rabinovich ML 《Prikladnaia biokhimiia i mikrobiologiia》2003,39(1):74-84
White rot fungi (Coriolus hirsutus, Coriolus zonatus, and Cerrena maxima from the collection of the Komarov Botanical Institute of the Russian Academy of Sciences) and filamentous fungi (Mycelia sterilia INBI 2-26 and Trichoderma reesei 6/16) were grown on oat straw-based liquid and solid media, as well as in a bench-scale reactor, either individually or as co-cultures. All fungi grew well on solid agar medium supplemented with powdered oat straw as the sole carbon source. Under these conditions, the mould Trichoderma reesei fully suppressed the growth of all basidiomycetes studied; conversely, Mycelia sterilia neither affected the development of any of the cultures, nor did it show any substantial susceptibility to suppression by their presence. Pure solid cultures of basidiomycetes, as well as the co-culture of Coriolus hirsutus and Cerrena maxima caused a notable bleaching of the oat straw during its consumption. When grown on the surface of oat straw-based liquid medium, the basidiomycetes consumed up to 40% polysaccharides without measurable lignin degradation (a concomitant process). Under these conditions, Mycelia sterilia decomposed no more than 25% lignin in 60 days, but this was observed only after polysaccharide exhaustion and biomass accumulation. In contrast, during solid state straw fermentation, white rot fungi consumed up to 75% cellulose and 55% lignin in 83 days (C. zonarus), whereas the corresponding consumption levels for co-cultures of Mycelia sterilia and Trichoderma reesei equaled 70 and 45%, respectively (total loss of dry weight ranged from 55 to 60%). Carbon dioxide-monitored solid-state fermentation of oat straw by the co-culture of filamentous fungi was successfully performed in an aerated bench-scale reactor. 相似文献
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Shaginian IA Khmel' IA Romanova IuM Veselova MA Chernukha MIu Chernin LS Sidorenko SV Lipasova VA Kovtun VP Alekseeva GV Alekseeva NV Stepanova TV Gintsburg AL 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》2003,(4):15-20
Described in the paper are characteristics of B. cepacia clinical strains isolated from patients at Moscow hospitals. The strains were investigated for the presence of proteolytic, chitinolytic, hemolytic and lipase activities as well as for presence of components of the "Quorum sensing" gene activity regulatory system by using biological test-systems and in the polymerase chain reaction with primers to genes cepI and cepR. 相似文献
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Hoogenraad CC Wulf P Schiefermeier N Stepanova T Galjart N Small JV Grosveld F de Zeeuw CI Akhmanova A 《The EMBO journal》2003,22(22):6004-6015
Bicaudal D is an evolutionarily conserved protein, which is involved in dynein-mediated motility both in Drosophila and in mammals. Here we report that the N-terminal portion of human Bicaudal D2 (BICD2) is capable of inducing microtubule minus end-directed movement independently of the molecular context. This characteristic offers a new tool to exploit the relocalization of different cellular components by using appropriate targeting motifs. Here, we use the BICD2 N-terminal domain as a chimera with mitochondria and peroxisome-anchoring sequences to demonstrate the rapid dynein-mediated transport of selected organelles. Surprisingly, unlike other cytoplasmic dynein-mediated processes, this transport shows very low sensitivity to overexpression of the dynactin subunit dynamitin. The dynein-recruiting activity of the BICD2 N-terminal domain is reduced within the full-length molecule, indicating that the C-terminal part of the protein might regulate the interaction between BICD2 and the motor complex. Our findings provide a novel model system for dissection of the molecular mechanism of dynein motility. 相似文献
26.
The oncoprotein kinase chaperone CDC37 functions as an oncogene in mice and collaborates with both c-myc and cyclin D1 in transformation of multiple tissues 下载免费PDF全文
Stepanova L Finegold M DeMayo F Schmidt EV Harper JW 《Molecular and cellular biology》2000,20(12):4462-4473
CDC37 encodes a 50-kDa protein that targets intrinsically unstable oncoprotein kinases including Cdk4, Raf-1, and v-src to the molecular chaperone Hsp90, an interaction that is thought to be important for the establishment of signaling pathways. CDC37 is required for proliferation in budding yeast and is coexpressed with cyclin D1 in proliferative zones during mouse development, a finding consistent with a positive role in cell proliferation. CDC37 expression may not only be required to support proliferation in cells that are developmentally programmed to proliferate but may also be required in cells that are inappropriately induced to initiate proliferation by oncogenes. Here we report that mouse mammary tumor virus (MMTV)-CDC37 transgenic mice develop mammary gland tumors at a rate comparable to that observed previously in MMTV-cyclin D1 mice. Moreover, CDC37 was found to collaborate with MMTV-c-myc in the transformation of multiple tissues, including mammary and salivary glands in females and testis in males, and also collaborates with cyclin D1 to transform the female mammary gland. These data indicate that CDC37 can function as an oncogene in mice and suggests that the establishment of protein kinase pathways mediated by Cdc37-Hsp90 can be a rate-limiting event in epithelial cell transformation. 相似文献
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Arefi'eva TI Mukhina SA Poliakov AA Stepanova VV Minashkin MM Gurskiĭ IaG Domogatskiĭ SP Krasnikova TL 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》1998,84(12):1432-1437
Urokinase activates adhesion of monocytic U937 cells to fibrinogen-coated surface. This effect is due to urokinase proteolytic activity and does not depend on the urokinase binding to its receptor. 相似文献
29.
Dmitry Bogolyubov Irina Stepanova Vladimir Parfenov 《BioEssays : news and reviews in molecular, cellular and developmental biology》2009,31(4):400-409
It is now clear that two prominent nuclear domains, interchromatin granule clusters (IGCs) and Cajal bodies (CBs), contribute to the highly ordered organization of the extrachromosomal space of the cell nucleus. These functional domains represent structurally stable but highly dynamic nuclear organelles enriched in factors that are required for different nuclear activities, especially RNA biogenesis. IGCs are considered to be the main sites for storage, assembly, and/or recycling of the essential spliceosome components. CBs are involved in the biogenesis of several classes of small RNPs as well as the modification of newly assembled small nuclear RNA. We have summarized data on the molecular composition, structure, and functional roles of IGCs and CBs in the nuclei of mammalian somatic cells and oocytes of some animals with a special focus on insects. We have focused on similarities and differences between the IGCs and CBs of oocytes and the well‐studied CBs and IGCs of cultured mammalian somatic cells. We have shown the heterogeneous character of oocyte IGCs and CBs, both in structure and molecular content. We have also demonstrated the unique capacity of oocytes to form close structural interactions between IGC and CB components. We proposed to consider these joint structures as integrated entities, sharing the features of both IGCs and CBs. 相似文献
30.
Robert F. Peters Luis Gutierrez-Rivera Steven K. Dew Maria Stepanova 《Journal of visualized experiments : JoVE》2015,(97)
Fabrication and characterization of conjugate nano-biological systems interfacing metallic nanostructures on solid supports with immobilized biomolecules is reported. The entire sequence of relevant experimental steps is described, involving the fabrication of nanostructured substrates using electron beam lithography, immobilization of biomolecules on the substrates, and their characterization utilizing surface-enhanced Raman spectroscopy (SERS). Three different designs of nano-biological systems are employed, including protein A, glucose binding protein, and a dopamine binding DNA aptamer. In the latter two cases, the binding of respective ligands, D-glucose and dopamine, is also included. The three kinds of biomolecules are immobilized on nanostructured substrates by different methods, and the results of SERS imaging are reported. The capabilities of SERS to detect vibrational modes from surface-immobilized proteins, as well as to capture the protein-ligand and aptamer-ligand binding are demonstrated. The results also illustrate the influence of the surface nanostructure geometry, biomolecules immobilization strategy, Raman activity of the molecules and presence or absence of the ligand binding on the SERS spectra acquired. 相似文献