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TT (TTV) Virus   总被引:1,自引:0,他引:1  
Characterization of TT virus (TTV), the history of its discovery, taxonomy and identification are reviewed as update on the diagnostics of TTV infection with PCR. The variability of the virus and resulting difficulties in the selection of a TTV DNA fragment for amplification are described. Data on the virus prevalence, replication and persistence are given. The pathogenetic importance of TTV is discussed with the account of different concepts.  相似文献
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Cp#2Yb (Cp#=C5H4(CH2)2NMe2) has been obtained by reaction of YbI2(THF)2 with 2 equiv. of C5H4(CH2CH2NMe2)K in THF. The X-ray structure analysis shows a bent structure with intramolecular coordination of both nitrogen atoms to ytterbium. The reaction of C60-fullerene with Cp#2Yb leads to the formation of the fullerenide derivative [Cp#2Yb]2C60, which shows an ESR signal in the solid state and in THF solution at room temperature (solid: ΔH = 50 G, G = 1.9992; solution: ΔH = 10 G, G = 2.0001) and a magnetic moment of 3.6 BM. The lutetium fullerenides CpLu(C60)(DME) (3) and Cp*Lu(C60)(DME)(C6H5CH3) (4), (Cp = η5−C5H5, Cp* = η5−C5Me5), were obtained by reaction of C60 with CpLu(C10H8) (DME) and Cp*Lu(C10H8) (DME) in toluene. Both complexes are paramagnetic (μeff = 1.4 and 0.9 BM) and exhibit temperature-dependent ESR signals (293 K: g = 1.992 and 2.0002 respectively).  相似文献
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Results are presented from optical measurements of the atomic hydrogen density and the gas temperature in a reactor for depositing diamond films from the plasmas of pulsed and continuous microwave discharges at a fixed mean microwave power. The results obtained make it possible to explain the fact that the growth rate of diamond films in the plasma of a pulsed microwave discharge is larger than that in a continuous microwave discharge. __________ Translated from Fizika Plazmy, Vol. 31, No. 4, 2005, pp. 376–384. Original Russian Text Copyright ? 2005 by Vikharev, Gorbachev, Koldanov, Radishchev.  相似文献
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A new type of magnetic confinement system—a Galathea with a myxine in the shape of a convex polyhedron—is proposed. The system was modeled experimentally by passing an RF current through the myxine. On the one hand, the myxine acts as an inductor whose electric field ionizes the gas and, on the other, it acts as an RF magnetic confinement system. A steady-state plasma produced and confined in this system is almost spherical in shape. The electron density and specific (per unit volume) glow intensity of the plasma produced are found to be higher than those in conventional helical inductors. __________ Translated from Fizika Plazmy, Vol. 31, No. 3, 2005, pp. 298–301. Original Russian Text Copyright ? 2005 by Gordienko, Dubinov, Zhuravlev, Ivanov, Repin.  相似文献
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The generation of ion-cyclotron radiation in a plasma resonator formed by an RF discharge in a linear mirror magnetic confinement system is revealed and investigated. It is shown that the experimental setup makes it possible to study the composition of a multicomponent discharge plasma and to detect multiply charged ions. Collisional losses in such a resonator are estimated, and the pressure range within which the growth rate of the ion-cyclotron instability substantially exceeds the collisional damping rate is determined. __________ Translated from Fizika Plazmy, Vol. 31, No. 8, 2005, pp. 701–706. Original Russian Text Copyright ? 2005 by Dobrokhotov, Lyukshin, Markov, Chugunov.  相似文献
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The problem is considered of configurations of a strongly magnetized inviscid plasma around a rotating magnetized central body. Strong plasma magnetization implies that the Hall conductivity is much lower than the transverse conductivity, which in turn is much lower than the longitudinal conductivity. For such conditions, a self-consistent set of equations is derived that describes the conduction current density, the magnetic and electric fields, and the angular frequency of the plasma rotation under the assumptions that the components of the dielectric tensor of the plasma envelope are known functions of height and that the plasma mass velocity has only the azimuthal component. Under the assumption that the transverse conductivity is constant over a magnetic surface, the nonlinear equations derived are solved in quadratures within the class of angular frequency distributions that are symmetric about the equatorial plane. A particular solution for the plasma configurations in a dipole magnetic field is considered that corresponds to a model exponential dependence of the transverse conductivity on the number of the L-envelope (or, equivalently, on the number of the unperturbed magnetic surface). __________ Translated from Fizika Plazmy, Vol. 31, No. 12, 2005, pp. 1139–1145. Original Russian Text Copyright ? 2005 by Soldatkin, Chugunov.  相似文献
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An unsteady discharge of a relativistic vacuum diode is studied analytically. The amplitude and rise time of the discharge current pulse are determined as functions of the input parameters of the problem. It is found that, in a nonrelativistic limit, the maximum attainable amplitude of the discharge current pulse is equal to J Alim = 9/4J CL, where J CL is the vacuum-diode limiting current prescribed by the 3/2 law. The parameters of the dipole moment of the layer formed above the grid anode are found in the nonrelativistic limit. __________ Translated from Fizika Plazmy, Vol. 31, No. 4, 2005, pp. 336–341. Original Russian Text Copyright ? 2005 by Soldatov.  相似文献
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Macroelectrodes and electrophysiological setup were used in experiments with stems of 15-day-old pumpkin (Cucurbita pepo L.) seedlings for computer-assisted data recording. It is shown that local bioelectric responses induced by graded local chilling are similar to the receptor potentials of animals. These responses increase gradually with stimulus strength and trigger the action potential generation when a temperature threshold is attained. The excitation threshold of cells in seedling stems displays the phenomenon of accommodation. Parameters of local bioelectric responses induced by intermittent cooling can undergo changes similar to sensitization-habituation patterns. The results indicate that local electrical responses may be involved in early stages of cooling perception in cells of higher plants devoid of locomotive functions. __________ Translated from Fiziologiya Rastenii, Vol. 52, No. 6, 2005, pp. 905–912. Original Russian Text Copyright ? 2005 by Opritov, Lobov, Pyatygin, Mysyagin.  相似文献
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