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VE Driianskaia 《Canadian Metallurgical Quarterly》1997,(5):78-82
In the process of batch cultivation the strains under study are capable of prolonged growth at low temperature in rich and poor nutrient media (with the term of observation equal to 4 months), while at a temperature of 37 degrees C microbial populations quickly die (in 8-35 days). In the absence of compounds containing carbon, hydrogen and nitrogen in the nutrient medium, Listeria can proliferate under such conditions. As established with the use of gas chromatography and the radioisotopic method, they can uptake carbon dioxide, hydrogen and nitrogen from the air gas mixture, using carbon of the first gas for the synthesis of the main biopolymers (proteins, lipids, carbohydrates, DNA and RNA) and the second one as the source of energy. During the cultivation of Listeria at low temperature in poor nutrient media (soil microecosystems, synthetic mineral media) they are capable of preserving and under favorable conditions also increasing their virulence. Its increase is facilitated by capsule formation, mobility, chemotaxis, adhesion and invasion enhancing under such conditions. 相似文献
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Nichtlineare Signalverarbeitung für die Sprachkommunikation 总被引:1,自引:1,他引:0
G. Kubin ÖVE 《e & i Elektrotechnik und Informationstechnik》1998,115(1):23-33
This paper provides an elementary introduction to problems and methods of nonlinear signal processing and presents on overview of recent developments in this field. An important topic is the modeling and processing of one-dimensional signals as exemplified in simple voice communication systems. The interplay and integration of deterministic and nondeterministic approaches is illustrated with recent research findings. 相似文献
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VE Barrios SC Middleton MA Kashem AM Havill CF Toombs CD Wright 《Canadian Metallurgical Quarterly》1998,63(26):2295-2303
Hyperresponsiveness of airway smooth muscle to allergens and environmental factors has long been associated with the pathophysiology of asthma. Tryptase, a serine protease of lung mast cells, has been implicated as one of the mediators involved in the induction of hyperresponsiveness. As a consequence, tryptase inhibitors have become the subject of study as potential novel therapeutic agents for asthma. Secretory leukocyte protease inhibitor (SLPI) is a naturally occurring protein of human airways which exhibits anti-tryptase activity. To assess the potential therapeutic utility of SLPI in asthma, its effects were evaluated using in vitro and ex vivo models of airway hyperresponsiveness and compared with the effects of the small molecule tryptase inhibitor APC-366. Our results demonstrate that SLPI inhibits tryptase-mediated hyperresponsiveness in vitro and attenuates the hyperresponsiveness observed in airway smooth muscle from antigen-sensitized animals subjected to antigen exposure. The small molecule tryptase inhibitor APC-366 has a similar inhibitory effect. Thus, tryptase appears to be a significant contributor to the development of hyperresponsiveness in these models. To the extent that tryptase contributes to the development and progression of asthma, SLPI may possess therapeutic potential in this disease setting. 相似文献
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P Esterre A Raobelison CE Ramarokoto VE Ravaoalimalala P Boisier J Roux 《Canadian Metallurgical Quarterly》1998,20(8):369-376
Increased serum concentrations of soluble intercellular adhesion molecule-1 (sICAM-1, CD54) and of soluble E- (CD62E), but not soluble P- (CD62P) and L- (CD62 L) selectins, were detected in Malagasy patients living in an hyperendemic focus of Schistosoma mansoni. Levels of sICAM-1 remained elevated for several months after treatment with praziquantel. Serum levels of ICAM-1, but not of other markers, were significantly correlated with the disease severity, as indicated by ultrasonographical data, and with some circulating fibrosis markers (at least hyaluronic acid). sICAM-1 level may reflect endothelial inflammatory reactions, probably harmful, in the liver and may be useful for monitoring morbidity evolution in schistosomiasis mansoni. 相似文献
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An earlier report indicated that a 26-amino-acid peptide (SA), comprised of the nuclear localization signal (NLS) of fibroblast growth factor-1 (FGF-1) and a membrane-permeable peptide, was able to stimulate DNA synthesis after it was taken up by NIH3T3 fibroblasts. Here, we report that SA, but not a mutant with the NLS motif destroyed, induced DNA synthesis in BALB/c3T3 murine fibroblasts, human vascular endothelial (HUVE) cells, and primary cultured hepatocytes, although the activity was weaker than that of FGF-1. The kinetics of SA-induced DNA synthesis and G1 cyclin expression were similar to those elicited by FGF-1, indicating that SA induces cell cycle progression. Kinetic analysis also suggested that SA stimulates only a fraction of the DNA replication in BALB/c3T3 cells. At high cell densities, SA-induced G1 cyclin expression and DNA synthesis were more strongly inhibited than those induced by FGF-1. SA did not induce cell division in HUVE and BALB/c3T3 cells and did not interfere with FGF-1-stimulated proliferation of HUVE cells. These results indicate that SA is able to partially induce cell cycle progression through a contact-inhibition sensitive signaling pathway, but it is insufficient to support cell mitosis. We also suggest that signaling by SA does not interfere with that of FGF-1. 相似文献