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1.
S. I. Tkachenko A. R. Mingaleev V. M. Romanova A. E. Ter-Oganes’yan T. A. Shelkovenko S. A. Pikuz 《Plasma Physics Reports》2009,35(9):734-753
Distribution of matter in the discharge channel formed upon a nanosecond electrical explosion of a single wire in air and
vacuum was studied experimentally. Simultaneous use of optical, UV, and X-ray diagnostics made it possible to distinguish
qualitatively different regions of the discharge channel, such as the current-carrying layers and the region occupied by a
weakly conducting cold plasma. Several series of experiments with 25-μm-diameter 12-mm-long wires made of different materials
were performed. The charging voltage and the current amplitude were varied in the ranges of U
0 = 10–20 kV and I
max ∼ 5–10 kA, respectively. Explosion regimes with a current pause and with and without current interruption, as well as with
wire preheating in air and vacuum, were studied. Shadow and schlieren images of the discharge channel were obtained using
optical probing at the second harmonic of a YAG: Nd+3 laser (λ = 0.532 μm, τ ∼ 10 ns). In the experiments carried out in vacuum, X-ray images of the discharge channel were also
obtained using an X-pinch as a point source of probing radiation and UV images were recorded using a four-frame MCP camera. 相似文献
2.
3.
Iu M Romanova I A Nastichkin A I Martsinkovskaia I A Rudnev V G Petrovskaia 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》1987,(9):19-24
The plasmid pSS120, determining the synthesis of species specific I phase antigen of Shigella sonnei is mobilized for genetic transfer into E. coli K12 recipient cells with the frequency 12-41%. The frequency depends on the type of mobilized plasmid and recipient strain. The I phase antigen is normally expressed in II phase recipient cells and in E. coli cells. During mobilization pSS120 forms cointegrates representing a recombinant of mobilizing and mobilized plasmids DNA. The study of pSS120 inheritance stability has shown the plasmid to be unstable during culturing of bacteria and to be partially lost from the parent Shigella sonnei strains as well as from the "hybrid" transconjugants obtained. The 60 Md plasmid present in the donor strains of Shigella sonnei is prone to structural fragmentation particularly expressed in Shigella sonnei/E. coli hybrids. 相似文献
4.
O L Krasil'nikova L N Anisova N B Romanova Iu E Bartoshevich 《Antibiotiki i khimioterapii͡a》1988,33(7):483-486
Conditions for efficient regeneration in mutant strains of the doxorubicin-producing organism Str. peucetius var. caesius were developed. The effect of the protoplast regeneration on changes in the proportion of the components of the anthracycline complex produced by these strains was shown. Variants with doxorubicin productivity 2 times higher than that of the parent strain were isolated. 相似文献
5.
A concept that considers the causative nature of the so-called "slow virus infections", causing syndromes of spongiform encephalopathies in man and animals as a chain autocatalytic process is put forward. According to this concept, PrP(27-30) protein, isolated recently from the brains of scrapie-infected animals, is a C-terminal domain of the normal protein component of brain tissue which is a latent zimogen. Certain clinical and experimental data are discussed within the framework of this concept. Exogenous proteinases are presumed to be capable of triggering such a chain autocatalytic process in the brains of susceptible animals. Indeed, in one of our experiments, a subtoxic dose of pronase injected into mouse brain induced the development of a syndrome indistinguishable from spongiform encephalopathy in its clinical and pathomorphological manifestations. The probable role of neuron-specific proteins of intermediate filaments in such pathological processes is discussed. It seems possible that spongiform encephalopathies are particular cases of pathological processes that have catalytic nature. Presumably, the Alzheimer disease has such a catalytic causative nature. 相似文献
6.
In experiments on rats a study was made of resorption from the gastrointestinal tract of simple salts, complex compounds and "biologically incorporated" forms of transuranium nuclides, the influence of age, pregnancy and chemically active substances (for instance, trivalent iron and ethyl alcohol) on this process. 相似文献
7.
E A Tolskaya L I Romanova M S Kolesnikova T A Ivannikova E A Smirnova N T Raikhlin V I Agol 《Journal of virology》1995,69(2):1181-1189
8.
The mass exchange characteristics of 50 m3 industrial fermentors with aerodynamic foam suppression and the effect of the specific power input on biosynthesis of penicillin were studied. A change in the specific power input from 1.3 to 1.9 kW/m3 had no effect on the level of the antibiotic accumulation when the medium with 8 per cent of lactose was used. An increase in the aeration rate from 1 to 1.2 m3/m3 X min provided a 1.1-fold increase in the penicillin activity of the fermentation broth. The use of the device for aerodynamic foam suppression with a system of automatic control of the partial pressure of dissolved carbon dioxide allowed decreasing 1.22-fold the oil use and increasing the process productivity by 10 per cent. 相似文献
9.
10.
Jolanda?HM?van Bilsen Josée?PA?Wagenaar-Hilbers Maarten?JF?van der Cammen Mariska?EA?van Dijk Willem?van Eden Marca?HM?WaubenEmail author 《Arthritis research & therapy》2002,4(4):R2
We have recently found that matrix metalloproteinases (MMPs) are targets for T-cell and B-cell reactivity in experimental
arthritis. In the present article, we investigate whether modulation of MMP-specific T-cell responses could influence the
course of adjuvant arthritis (AA). Lewis rats were treated nasally with MMP peptides prior to or after AA induction. Administration
of the MMP-10 or the MMP-16 peptide prior to AA induction reduced the arthritic symptoms. In contrast, administration of the
MMP-10 peptide after AA induction aggravated the arthritic symptoms. The present study shows the possible usefulness of MMP
peptides for immunotherapy. However, a clear understanding of proper timing of peptide administration is crucial for the development
of such therapies. 相似文献