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21.
Kalnina I Klimkane L Kirilova E Toma MM Kizane G Meirovics I 《Journal of fluorescence》2007,17(6):619-625
The fluorescent probe-aminoderivative of benzanthrone, ABM (developed at Riga Technical University, Riga, Latvia) was used
to characterize the membranes of lymphocytes of cancer patients: 46 patients with gastrointestinal diseases, 13 patients having
different primary localizations with massive metastases and intoxication. Patients were divided into three groups: (1) with
decreased fluorescence intensity, (2) normal fluorescence intensity, (3) increased fluorescence intensity. The lymphocytes
distribution among subsets differed between groups, in correspondence to the level of florescence intensity. Surgical treatment
affected the main immunological parameters and elevated the functional activity of lymphocytes. In the advanced tumors group,
fluorescence intensity correlates with the survival rate. Results suggest that determination of lymphocytes functional activity
by ABM can aid evaluation of the immune status in cancer patients. 相似文献
22.
A rapid conversion of aldehydes to corresponding nitriles has been achieved under microwave irradiation using hydroxylamine and phthalic anhydride or hydroxylamine and Envirocatalyst EPZGR in solvent free conditions. 相似文献
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25.
Formation of the plasma potential in a plasma that contains energetic electrons and is bounded by a floating collector that
emits electrons is studied theoretically. The problem is treated by a static. kinetic plasma-sheath model of Schwager and
Birdsall [Phys. Fluids B2 (1990) 1057], which we have extended in order to include additional energetic electron population. The distribution of these
electrons is assumed to be a high-temperature Maxwellian. They are called hot electrons. In the paper we study effects of
the density and temperature of the hot electrons on the formation of the plasma potential. The model shows that for certain
densities and temperatures of the hot electron population plasmas with two different plasma potentials can coexist in the
system. These two plasmas are separated spatially by a double layer. For the case when there is no emission of electrons from
the collector, results of the model are compared with computer simulation and very good agreement between the model and the
simulation is found. The simulation also confirms existence of two plasmas with two different potentials separated by a double
layer. 相似文献
26.
In situ observation of photoinduced refractive-index changes in filaments formed in glasses by femtosecond laser pulses 总被引:5,自引:0,他引:5
We investigated the relationship between the formation of filaments and local refractive-index changes induced by femtosecond laser pulses in silica glass. In situ observation revealed that the location of a filament coincided with that of the refractive-index change. Observation also showed that the region of refractive-index change was elongated toward the upstream direction of the laser pulses with increasing exposure time. The region of refractive-index change was several hundred micrometers long, and its diameter was smaller than 2 mum. The refractive-index change was confirmed by two of three different methods to be as large as 0.8 x 10(-2). 相似文献
27.
Henrique E. Toma Tulio E. Chavez-Gil Reginaldo C. Rocha Hercílio R. Rechenberg 《Journal of inclusion phenomena and macrocyclic chemistry》1999,34(1):57-68
A novel multibinding species has been obtained by attaching four aliphatic polyamine chains to an iron(II)-polyimine centre, derived from 2,6-diacetylpyridine. Molecular simulations for the complex corroborate the evidence from 1H NMR spectroscopy of a symmetric structure, with the four polyamines displaying a tetrahedral arrangement around the metal centre. The protonated polyamine complex interacts with hexacyanoferrate(II) ions, leading to an inclusion compound which has been characterized based on vibrational and Mössbauer spectroscopy, and on cyclic voltammetry. 相似文献
28.
Aida Toma 《Rendiconti del Circolo Matematico di Palermo》2009,58(1):29-40
This paper proves a new integral representation theorem for powers of elements in locally m-convex algebras. It is shown that the conditions handled in this theorem are satisfied for any sequentially complete locally
m-convex Q-algebra. Various applications of this result concerning the spectrum, the spectral radius or the numerical radius are given.
相似文献
29.
Andrei Medvedovici Florin Albu Iuliana Daniela Sora Stefan Udrescu Toma Galaon Victor David 《Biomedical chromatography : BMC》2009,23(10):1092-1100
A sensitive method for determination of free captopril as monobromobimane derivative in plasma samples is discussed. The internal standard (IS) was 5‐methoxy‐1H‐benzimidazole‐2‐thiol. Derivatization with monobromobimane immediately after blood collection and plasma preparation prevents oxidation of captopril to the corresponding disulfide compound and enhances the ionization yield. Consequently, derivatization enhances sample stability and detection sensitivity. Addition of the internal standard was made immediately after plasma preparation. The internal standard was also derivatized by monobromobimane, as it contains a thiol functional group. Preparation of plasma samples containing captopril and IS derivatives was based upon protein precipitation through addition of acetonitrile, in a volumetric ratio 1:2. The reversed‐phase liquid chromatographic separation was achieved on a rapid resolution cartridge Zorbax SB‐C18, monitored through positive electrospray ionization and tandem MS detection using the multiple‐reaction monitoring mode. Transitions were 408–362 amu for the captopril derivative and 371–260 amu for the internal standard derivative. The kinetics of captopril oxidation to the corresponding disulfide compound in plasma matrix was also studied using the proposed method. A linear log–log calibration was obtained over the concentration interval 2.5–750 ng/mL. A low limit of quantitation in the 2.5 ng/mL range was obtained. The analytical method was fully validated and successfully applied in a three‐way, three‐period, single‐dose (50 mg), block‐randomized bioequivalence study for two pharmaceutical formulations (captopril LPH 25 and 50 mg) against the comparator Capoten 50 mg. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
30.
We present a general formulation of Floquet states of periodically time-dependent open Markovian quasifree fermionic many-body systems in terms of a discrete Lyapunov equation. Illustrating the technique, we analyze periodically kicked XY spin-? chain which is coupled to a pair of Lindblad reservoirs at its ends. A complex phase diagram is reported with reentrant phases of long range and exponentially decaying spin-spin correlations as some of the system's parameters are varied. The structure of phase diagram is reproduced in terms of counting nontrivial stationary points of Floquet quasiparticle dispersion relation. 相似文献