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961.
Conclusions Neutrophils can be directly stimulated by endothelial cell suspensions, an observation that has also been made by experiments with nylon fiber, as an artificial model for PMNL/EC interactions [5]. As shown by experiments with endothelial cell suspensions a further amplification of this process following LPS-priming up to 10 ng/ml blood has been demonstrated.Unstimulated neutrophils do not lead to an endothelial cell damage, as also could be demonstrated by electron micrographs. An increased 111In release occurred following neutrophil stimulation between 10 and 20 ng LPS/ml blood, but cannot be explained by an increased oxygen radical production of neutrophils. Therefore, these data suggest, that other neutrophil derived products rather than oxygen radicals contribute to an endothelial cell damage in this system.
Chemiluminescenz-Antwort und Endothelzellschaden nach Lipopolysaccharid-Stimulation polymorphkerniger Leukocyten相似文献
962.
This is a report on the single and double charge exchange reactions on nuclie. The emphasis is on recent experimental results and calculations. We limit ourselves to pion energies below 300 MeV. The experimental results and complexity. We present the current level of understanding of the various aspects of the charge exchange process. 相似文献
963.
964.
Arthur E. Jonas George K. Schweitzer F.A. Grimm Thomas A. Carlson 《Journal of Electron Spectroscopy and Related Phenomena》1973,1(1):29-66
The photoelectron spectra of CF4, SiF4, GeF4, C(CH3)4, Si(CH3)4, Ge(CH3)4, Sn(CH3)4, and Pb(CH3)4 h 相似文献
965.
Z. A. Rotenberg N. M. Alpatova E. V. Ovsyannikova S. S. Kirchmeyer F. Jonas 《Russian Journal of Electrochemistry》2002,38(11):1244-1249
The photoelectrochemical behavior of a polymer electrode based on poly(3,4-ethylenedioxythiophene) (PEDT) is studied in acetonitrile solutions during the cathodic reduction of oxygen. The measurements are taken on PEDT films 490 nm thick deposited onto a platinum support in oxygen-saturated 0.1 M Bu4NBF4 solutions. The electrode was illuminated with a light of a wavelength 487 nm from a helium–cadmium laser in conditions of modulated illumination, and in doing so, the real and imaginary components of an alternating photocurrent were measured at different modulation frequencies. The peculiarity of the photoelectrochemical behavior of PEDT manifests itself in the emergence of an anodic photocurrent, which increases with a change in potential in the cathodic direction. At low modulation frequencies, the real and imaginary components are of the same sign, whereas at high modulation frequencies the components have opposite signs (photocurrent lags behind a change in the light intensity). The emergence of an anodic photocurrent is connected with the cathodic reduction of oxygen and the formation in a near-electrode layer of radical anion O–
2. Such a behavior of PEDT, which makes it different from other polymers of the thiophene series, is explained by different potentials of their anodic oxidation, to which a conductive state of the polymer is related. 相似文献
966.
Frank Jonas 《manuscripta mathematica》1990,67(1):35-39
Zusammenfassung LetD:G→GL(n,C) be an irreducible linear representation of a finite groupG with the characterX. IfD is realizible in Q(ξ
m
) and Q(ξ
m′
) we give a condition for then realizability ofD in Q(ξ(m′)). If the degreen is a prime ≠ 2, we show thatD realizible in Q(ξ
f
), wheref is the conductor of the abelian extensionQ(X)/Q. 相似文献
967.
Jonas Mockus 《Journal of Global Optimization》1994,4(4):347-365
In this paper a review of application of Bayesian approach to global and stochastic optimization of continuous multimodal functions is given. Advantages and disadvantages of Bayesian approach (average case analysis), comparing it with more usual minimax approach (worst case analysis) are discussed. New interactive version of software for global optimization is discussed. Practical multidimensional problems of global optimization are considered 相似文献
968.
Abstract— Bleached purple membrane normally binds Ca2+ and Mg2+ , which can be removed by the divalent cation chelator ethylenediaminetetraacetic acid (EDTA). Regeneration of pigments from EDTA-treated bleached membrane (apomembrane) and retinal leads to the formation of blue membrane at pH 4.8, and purple membrane at neutral pH. The pigments take much longer to regenerate than with un-deionized apoprotein. Adding back cations to the deionized apomembrane only partially speeds up the regeneration process. Like native purple membrane, the regenerated purple membrane also undergoes a photocycle and shows a light-induced proton release and uptake, although with much slower kinetics than the native species. Thus, cations control the kinetics of pigment regeneration, and also some aspects of the pigment's conformation which controls the photocycle kinetics. The removal and replacement of the cations is not completely reversible, suggesting the cations are not merely bound in the double layer. 相似文献
969.
Peter Jonas 《Mathematische Nachrichten》1988,137(1):257-281
970.