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281.
In this study the outer membrane protein (OMP) composition of six Pseudomonas aeruginosa strains had been analyzed by conventional CE and microchip electrophoresis. Bacterial OMPs are important virulence factors and play a significant role in the pathogenesis of infectious diseases. Changes in their composition might refer to the altered pathogenic properties and antibiotic sensitivity of a certain strain. Pathogenic bacteria invading the human host have to multiplicate under iron-restricted conditions that induce changes in the OMP composition. High-molecular-weight OMPs have to be expressed, which serve as receptors for the iron-siderophore complexes. OMP patterns of bacteria obtained by the two different methods in this study were similar, all major proteins could be detected by both techniques, and the molecular weights showed good correlations, although direct comparison of the peak areas is not straightforward due to the different detection methods (UV and LIF). Changes in OMP composition under iron restriction could be detected, and appearance of a 92 kDa protein in all six P. aeruginosa strains and a 94 kDa protein in the KT 2 strain could be demonstrated. Besides that up- and downregulation of certain proteins could be also detected. The increased separation speed, picoliters of sample consumption, baseline separation achieved more frequently by this method--especially in the high-molecular-weight region--showed the advantages of microchip electrophoresis in the analysis of clinical samples. 相似文献
282.
Gaál V Kilár F Acs B Szijjártó Z Kocsis B Kustos I 《Colloids and surfaces. B, Biointerfaces》2005,45(3-4):125-130
Implantation of artificial intraocular lenses into the eye during ophthalmic surgical procedures ensures an unliving surface on which bacterial pathogens may attach and form biofilms. Despite antibiotic treatment bacteria growing in biofilms might cause inflammation and serious complications. In this study the adhesive ability of 7 Staphylococcus aureus and 11 coagulase-negative Staphylococcus (CNS) strains to the surface of acrylic intraocular lenses had been examined by the ultrasonic method. In untreated cases adhesion of the S. aureus and CNS strains did not differ significantly. We could not demonstrate significant differences between the adhesive ability of the standard strains and the clinical isolates. In this study a single – 60 min long – antibiotic (ciprofloxacin and tobramycin) treatment had been applied, that correlate well with the single or intermittant antibiotic prophylaxis of patients. Ciprofloxacin administration was able to reduce significantly the number of attached cells on the surface of acrylic lenses both in the case of S. aureus and CNS strains. Dependence of the effect from concentration could also be demonstrated. Tobramycin treatment was able to inhibit significantly the attachment of S. aureus cells. Despite the debate on antibiotic prophylaxis we presented in our experiments that a single antibiotic administration can decrease the attachment of bacterial cells to the surface of acrylic intraocular lenses, and might be effective in the prevention of postoperative endophthalmitis, that is a rare but serious complication of ophthalmic surgery. 相似文献
283.
Summary The geodesic graph of Riemannian spaces all geodesics of which are orbits of 1-parameter isometry groups was constructed by
J. Szenthe in 1976 and it became a basic tool for studying such spaces, called g.o.\ spaces. This infinitesimal structure
corresponds to the reductive complement <InlineEquation ID=IE"1"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"2"><EquationSource
Format="TEX"><![CDATA[$]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>\mathfrak m$ in the case
of naturally reductive spaces. The systematic study of Riemannian g.o. spaces was started by O. Kowalski and L.~Vanhecke in
1991, when they introduced the most important definitions, classified the low-dimensional examples and described the basic
constructions of this theory. The aim of this paper is to investigate a connection theoretical analogue of the concept of
the geodesic graph. 相似文献
284.
Symmetry breaking solutions of several model theories are investigated with the result that constant gauge transformations of the fields describing zero mass Goldstone particles are responsible for the formal possibility of the spontaneous symmetry breaking.
相似文献285.
I. Zay A. Vértes G. Takácsi Nagy M. Suba K. Burger 《Journal of Radioanalytical and Nuclear Chemistry》1985,88(2):343-350
Iron injections containing high spin iron(III) complexes may undergo a reductive decomposition during preparation or storage. This process was investigated by the Mössbauer spectroscopy of ice samples prepared by quick-freezing of the injection. The comparison of three model compounds and the correlation between the osmotic pressure of the solutions and their iron(II) concentration formed in the decomposition process and determined by Mössbauer measurements revealed the reason and mechanism of the decomposition. 相似文献
286.
Ferenc Szász 《Monatshefte für Mathematik》1973,77(4):354-356
287.
The conditions of the formation of yttrium and lanthanide 5-chloro-2-nitrobenzoates were studied and their quantitative composition
and solubilities in water at 298 K were determined. They are anhydrous or hydrated complexes and their solubilities are of
the order of 10-3 mol dm-3. The IR and X-ray spectra for the complexes were recorded. All complexes are crystalline compounds.
Their thermal decomposition was studied. It was found that on heating above 523 K the complexes decompose explosively. Therefore
their thermal decomposition was carried out in the temperature range 273-523 K. Hydrated complexes lose crystallization water
molecules in one step. From the results it appeared that during dehydration process no transformation of nitro group to nitrito
took place. Some of physico-chemical properties of rare earth element 5-chloro-2-nitrobenzoates were compared with 2-nitro-
and 3-chlorobenzoates of those elements.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
288.
D. L. Nagy R. Doerfler B. Molnár G. Ritter J. Waigel N. Zeman 《Hyperfine Interactions》1983,16(1-4):1051-1055
The Fe3+ fraction after the EC of57Co is usually evaluated supposing that ferric ions contribute a quadrupole doublet to Mössbauer emission spectra. It is shown that a not sufficiently fast relaxation of the electron spins may falsify the evaluated intensity even by a factor 2. Additional information can be gained from measurements performed in a large velocity span at low temperatures in high magnetic fields. 相似文献
289.
Varga L Nagy T Dorman G Kalman F Urge L Darvas F 《Journal of combinatorial chemistry》2006,8(3):338-343
We present here the discovery of a novel, versatile, multicomponent reaction leading to various 4-[4-(pyridinium-1-yl)-2,5-dioxo-2,5-dihydro-1H-pyrrol-3-yl]-2H-pyrazol-3-olate inner salts. The structure of the unusual zwitterionic inner salts was elucidated, and the scope of the novel reaction was investigated. After rapid optimization, the reaction was adapted to parallel synthesis, and an 800-membered compound library was produced. 相似文献
290.
A general summability method, the so-called θ-summability is considered for multi-dimensional Fourier series. Equivalent conditions
are derived for the uniform and L
1-norm convergence of the θ-means σ
n
θ
f to the function f. If f is in a homogeneous Banach space, then the preceeding convergence holds in the norm of the space. In case θ is an element
of Feichtinger’s Segal algebra
, then these convergence results hold. Some new sufficient conditions are given for θ to be in
. A long list of concrete special cases of the θ-summation is listed. The same results are also provided in the context of
Fourier transforms, indicating how proofs have to be changed in this case.
This research was supported by Lise Meitner fellowship No M733-N04 and the Hungarian Scientific Research Funds (OTKA) No T043769,
T047128, T047132. 相似文献