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31.
Zagubizhenko MV Iusipovich AI Pirutin SK Minaev VL Kudryashov IuB 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2011,51(6):715-720
The plasma membrane dose-dependent damage of UV(B)-irradiated mouse peritoneal macrophages was investigated using laser interference microscopy (LIM). LIM is a method which allows one to estimate morphological and functional parameters of a cell without dyeing or introduction of other substances which can affect the cell condition. This makes it possible to reduce and accelerate the procedure of counting the damaged cells as compared with the methods using different dyes. The value of optical path difference (OPD)--a variable proportional to the object thickness and the difference in the refractive indices of the object and the surrounding medium was used for estimation of the cell damage. Also compared was usability of LIM and microfluorimetry assay in investigations of the UV(B)-irradiated macrophage plasma membrane. 相似文献
32.
Evolution of the WANCY region in amniote mitochondrial DNA 总被引:7,自引:1,他引:6
In most vertebrate mitochondrial genomes, the site for initiation of
light-strand replication, OL, is found within a cluster of five transfer
RNA (tRNA) genes (tRNA(Trp), tRNA(Ala), tRNA(Asn), tRNA(Cys), and
tRNA(Tyr)). This region and part of the adjacent cytochrome c oxydase
subunit I (COI) gene were sequenced for two crocodilian, two turtle, and
one snake species and for Sphenodon punctatus; part of the adjacent
nicotinamide adenine dinucleotide dehydrogenase subunit 2 (ND2) gene was
also sequenced for the crocodilian and turtle species. All had the typical
vertebrate gene order. The turtles and the snake have a lengthy noncoding
sequence between the tRNA(Asn) and tRNA(Cys) genes that we assumed to be
homologous to the mammalian OL. The crocodilians and Sphenodon lack such a
sequence, a condition they share with birds. Most proposed phylogenies for
the amniotes require that OL at this position was lost at least twice
during their diversification or was evolved independently more than once.
Within the five tRNA genes, frequencies of substitutions are much higher in
loops than in stems. Many loops vary dramatically in size among the
species; in the most extreme case, the D-arm of the Sphenodon tRNA(Cys) is
a "D-arm replacement" loop of seven nucleotides. Frequency of transitions
in stems is relatively uniform across tRNAs, but frequency of transversions
varies greatly. Mismatches in stems are infrequent, and their relative
frequency in a specific tRNA is unrelated to the frequency of substitution
in the corresponding gene. Several features of mammalian mitochondrial
tRNAs are conserved in WANCY tRNAs throughout amniotes. The inferred
initiation codon for COI is GTG in crocodilians, turtles, and the snake, a
condition they share with fishes, certain amphibians, and birds. TTG
appears to be the initiation codon for COI in Sphenodon; if correct, this
would be a novel initiation codon for vertebrate mitochondrial DNA.
Phylogenetic analyses of the inferred amino acid sequences of ND2 and COI
support the sister-group relationship of birds and crocodilians and suggest
that mammals are an early derived lineage within the amniotes.
相似文献
33.
34.
Yu. V. Petrov M. I. Patrov V. K. Gusev A. E. Ivanov V. B. Minaev N. V. Sakharov S. Yu. Tolstyakov G. S. Kurskiev 《Plasma Physics Reports》2011,37(12):1001-1005
In the experiments carried out on the Globus-M tokamak in regimes with injection of 26-keV neutral beams with a power of 0.75–0.85
MW, two branches of instabilities excited by fast ions were observed in the early stage of a discharge: a low-frequency energetic
particle mode (EPM) in the frequency range of 5–30 kHz and a high-frequency mode in the range of 50–200 kHz, identified as
a toroidal Alfvén eigenmode (TAE). The TAE developed in the initial phase of the discharge at q(0) > 1 and terminated when sawtooth oscillations were excited at q(0) < 1. The spectrum and spatial localization of the mode agree with predictions of the linear theory. The modes observed
in the Globus-M tokamak possess both properties common to other tokamaks and their own specific features. 相似文献
35.
Trotta MB Serro Azul JB Wajngarten M Fonseca SG Goldberg AC Kalil JE 《Immunity & ageing : I & A》2011,8(1):4
Background
The increase in life expectancy within the general population has resulted in an increasing number of elderly adults, including patients with Down syndrome (DS), with a current life expectancy of about 50 years. We evaluate the parameters of humoral and cellular immune response, the quantitative expression of the regulator of calcineurin1 gene (RCAN1) and the production of cytokines. The study group consisted of adults DS (n = 24) and a control group with intellectual disability without Down syndrome (ID) (n = 21) and living in a similar environmental background. It was evaluated serology, immunophenotyping, the quantitative gene expression of RCAN1 and the production of cytokines. 相似文献36.
S. V. Arlantsev G. P. Kuz’min I. M. Minaev G. P. Mkheidze O. V. Tikhonevich D. K. Ul’yanov 《Plasma Physics Reports》2011,37(13):1109-1118
Lasers, sources of coherent UV and vacuum UV radiation, plasmachemical reactors, reactors for cleaning fouled gases, etc.,
can be classified as devices the working medium of which is plasma formed as a result of the interaction of a high-current
relativistic electronic beam with gas. Efficiency of such devices which are united under the common name “systems of injection
gas electronics” (SIGE) depends mainly on the efficiency of energy transfer from a beam to gas (ηg = W
g
/W
b
) and that of the transform of the energy transferred to gas into the energy of the ultimate product W
in (ηin = W
in/W
g
). As a special case of SIGE, an experimental bench laser is considered. The new efficient method of pumping is supposed to
be implemented on this laser to optimize the energy contribution η
g
and useful output ηin. 相似文献
37.
E. N. Istomin D. M. Karfidov I. M. Minaev A. A. Rukhadze V. P. Tarakanov K. F. Sergeichev A. Yu. Trefilov 《Plasma Physics Reports》2006,32(5):388-400
A study is made of a quarter-wave asymmetric dipole antenna in which the conducting rod is replaced by a plasma column with an electron density much higher than the critical density. The parameters of such an antenna are determined by the exited surface wave, which affects the electromagnetic field structure in the near-field zone. It is shown analytically, numerically, and experimentally that the resonant length of the plasma dipole antenna is close to one-quarter of the length of the surface wav and that the conversion efficiency of plasma antenna power into radiation can be no worse than that of a metal dipole antenna. It is also shown experimentally that the plasma in a dipole antenna can be self-consistently excited by an RF oscillator and that the excited RF oscillations can be efficiently radiated into the surrounding space. 相似文献
38.
39.
B. B. Ayushin A. G. Barsukov V. K. Gusev L. A. Esipov E. G. Zhilin G. S. Kurskiev R. G. Levin V. M. Leonov V. B. Minaev M. I. Patrov Yu. V. Petrov N. V. Sakharov G. N. Tilinin S. Yu. Tolstyakov F. V. Chernyshev 《Plasma Physics Reports》2008,34(2):81-94
Results from experimental studies on the injection of high-energy neutral hydrogen beams into the plasma of the Globus-M spherical tokamak are reviewed. In the Introduction, the importance of these studies for implementing the controlled fusion research program and constructing the ITER tokamak is proved. Some problems related to the use of neutral beam injection in small and low-aspect-ratio tokamaks is analyzed. Results are presented from numerical simulations of the experiment by using the ASTRA transport code. It is shown that the use of neutral beam injection in the Globus-M tokamak ensures efficient ion heating and increases the plasma stored energy. The greater part of the review is devoted to the survey of experiments on the injection of 22-to 30-keV hydrogen and deuterium beams with a power of 0.4–0.8 MW into the plasma of the Globus-M spherical tokamak in a wide range of plasma currents and densities. The experimental results are analyzed and compared with the results of numerical simulations. The achievement of top plasma parameters is highlighted. 相似文献
40.