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971.
972.
D. Jorquera C. Navarro V. Rojas G. Turra J. Robeson 《Biocontrol Science and Technology》2015,25(8):970-974
We evaluated the effectiveness of phages on meats and goat cheese contaminated with Salmonella Enteritidis (SE). In meats, reductions of SE were observed during the whole experiment, while in goat cheese a reduction was only observed at day 3. We discuss the relevance of phages as a biocontrol in food. 相似文献
973.
974.
Nina I. Smirnova Galina V. Chekhovskaya Natalia I. Davidova Ludmila F. Livanova Galina A. Yeroshenko 《FEMS microbiology letters》1996,136(2):175-180
Abstract The presence of a temperate phage was demonstrated in a strain of Vibrio cholerae O139 isolated from a patient. Spontaneous variants with translucent colonies had lost this phage. The loss of the phage was associated with increased hydrophobicity, indicating the loss of the capsule. These clones were sensitive to serum bactericidal activity, showed decreased expression of such presumed virulence factors as proteases, motility and mannose-sensitive pili. Furthermore, excision of the phage made the strain dependent on purines for growth. 相似文献
975.
Incubation of peritoneal macrophages in vitro before fixation increased their ability to present exogenous peptides to 3A9 T hybridoma cells. The enhanced level of presentation correlated with a greatly increased, peptide-specific adhesion of 3A9 cells to the macrophages, whereas peptide-independent adhesion was minimal and essentially unaltered. 3A9 cells exhibited rapid peptide-specific adhesion (plateau by 5 to 10 min) and deadhesion (complete reversal by 5 min). Peptide-specific adhesion was blocked by anti-I-Ak and anti-LFA-1. Interaction of T cell receptors and CD-4 with peptide-I-Ak complexes appeared to provide little direct contribution to the avidity of T cell-macrophage adhesion, but activated a LFA-1-mediated adhesion mechanism. In addition, anti-T cell receptor, anti-CD3, and anti-CD4 antibodies themselves activated LFA-1-dependent adhesion in the absence of peptide. Unlike the peptide-induced adhesion, this adhesion was similar for macrophages whether or not they were incubated in vitro before fixation. We conclude that the different macrophage populations supported LFA-1-mediated adhesion equally. Therefore, the enhancement of T cell stimulation observed after in vitro incubation of macrophages was due to increased peptide presentation and consequently increased triggering of LFA-1-mediated adhesion. Mechanisms may exist to regulate the effectiveness with which peptide-class II MHC complexes are displayed for T cell recognition. 相似文献
976.
977.
A. V. Timofeev 《Plasma Physics Reports》2009,35(11):912-923
A previously developed method for analyzing the plasma processing of spent nuclear fuel is generalized to a plasma containing
multicharged fuel ions. In such a plasma, ion cyclotron resonance heating of nuclear ash ions should be carried out in two
monochromatic RF fields of different frequencies, provided that the fraction of ξ multicharged ions is small, ξ ≤ 0.1, a condition
that substantially restricts the productivity of systems for processing spent nuclear fuel. Ways of overcoming this difficulty
are discussed. 相似文献
978.
J.J. Virgen-Ortíz V. Ibarra-Junquera P. Escalante-Minakata J.A. Osuna-Castro J. de J. Ornelas-Paz N.A. Mancilla-Margalli R.L. Castañeda-Aguilar 《Analytical biochemistry》2013
This work presents a rapid and simple freeze centrifugation method to concentrate dilute protein solutions for detection by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS–PAGE) Coomassie blue staining. Moreover, a simple way to assemble a cryoconcentration device is presented, and its use is discussed. Commercial purified protein standard and an enzyme with high fructosyltransferase (FTase) activity, coming from target fractions obtained by chromatographic separation, were used as an example. FTase, coming directly from the chromatographic fractions, was difficult to view through SDS–PAGE analysis; however, it was easily visualized, and its activity was enhanced, after the application of the freeze centrifugation protocol presented here. 相似文献
979.
980.
Measurements of the coefficient of water molecules self-diffusion (D) and the time of spin-lattice relaxation (T
1) in prosenchyme (elongated) plant cells, whose length significantly exceeding their transverse size, show that the orientation of plant tissues in the H
0field significantly affects the measured parameters. We conclude that this effect should be taken into account in experiments on the measurement of self-diffusion coefficients and time of proton spin-lattice relaxation in plant tissues containing prosenchyme cells. 相似文献