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991.
Improved quantitation of 13-cis- and all-trans-acitretin in human plasma by normal-phase high-performance liquid chromatography. 总被引:1,自引:0,他引:1
E Meyer W E Lambert A P De Leenheer J P Bersaques A H Kint 《Journal of chromatography. A》1991,570(1):149-156
A reliable analytical method has been developed for measurement of 13-cis- and all-trans-acitretin (Neotigason) in human plasma by normal-phase high-performance liquid chromatography, with ultraviolet detection. Human plasma was obtained after centrifugation of whole blood samples and deproteinized by ethanolic denaturation. After liquid-liquid extraction with water-n-hexane, and aliquot ws chromatographed on a silica column using isocratic elution with n-hexane-methylsalicylate-acetic acid (200:18:0.6, v/v). The wavelength was set at 360 nm, and for plasma samples a limit of quantification of 3-4 ng/ml was obtained. All manipulations were carried out under dim light conditions to prevent photoisomerization. 相似文献
992.
W. D. Hutchison A. V. J. Edge N. Yazidjoglou D. H. Chaplin 《Hyperfine Interactions》1992,75(1-4):291-298
The high resolution hyperfine spectroscopy, modulated adiabatic passage of oriented nuclei (MAPON), has been applied for the
first time to high purity, elemental systems. Detailed comparisons between the electric quadrupole hyperfine interactions
(EQI’s) and, in particular, their distributions, are obtained for60CoCo where the hosts are a single crystal of hcp cobalt and a polycrystalline cobalt foil of predominantly fcc character. For
hcp Co, with the electronic magnetization, M, parallel to the c-axis, the mode value P/h=3e2qQ/4I(2I−1)h=−48.5(5) kHz. This fractional distribution implies the sharpest electric field gradient (efg) measured in a metal
to date, using MAPON spectroscopy, in excess of two times sharper than that of the most dilute impurity efg in a crystallographically
cubic ferromagnetic host. The mode efg is Vzz=−27.3(32)×1019 Vm−2. For the polycrystalline, predominantly fcc foil, prepared by quenching, the EQI mode value is P/h=−6.2(4) kHz with a FWHM
of 12.0(7) kHz yielding a mode efg of Vzz=−3.5(5)×1019 Vm−2. 相似文献
993.
A series of 7-amino- and polyaminosterol analogues of squalamine and trodusquemine were synthesized involving a new stereoselective titanium reductive amination reaction in high chemical yields of up to 95% in numerous cases. These derivatives were evaluated for their in vitro antimicrobial properties against human pathogens. All the compounds present excellent activities against Gram-positive bacteria exhibiting similar results against Staphylococcus aureus and Streptococcus faecalis with minimum inhibitory concentrations (MICs) varying from 2.5 to 10 μg/mL. Numerous derivatives possess also MICs against Gram-negative Escherichia coli bacteria (MICs varying from 2.5 to 10 μg/mL) suggesting that nature of the amino group attached to the sterol moiety plays an important role on the activities of such products. 相似文献
994.
Given an integer n ≥ 2, let λ(n) := (log n)/(log γ(n)), where γ(n) = Π
p|n p, stand for the index of composition of n, with λ(1) = 1. We study the distribution function of (λ(n) – 1) log n as n runs through particular sets of integers, such as the shifted primes, the values of a given irreducible cubic polynomial
and the shifted powerful numbers.
Research supported in part by a grant from NSERC.
Research supported by the Applied Number Theory Research Group of the Hungarian Academy of Science and by a grant from OTKA.
Professor M.V. Subbarao passed away on February 15, 2006.
Received: 3 March 2006 Revised: 28 October 2006 相似文献
995.
S J Cox 《The Journal of the Operational Research Society》2007,58(1):2-9
The UK nuclear industry is currently undergoing a series of dramatic changes. Important, among many is the establishment of the Nuclear Decommissioning Authority (NDA) with an associated impact on service delivery. At the same time, the debate on the future of our energy supply in the UK is increasingly focused on the question of the nuclear option. Issues of safety and reliability are paramount for the nuclear industry given both the nature of the hazard and the associated public perceptions of the associated risks. This paper explores linked developments in human factors and the management of safety in the nuclear industry in the context of unprecedented change. 相似文献
996.
Piotr W. Nowak 《Journal of Functional Analysis》2007,243(1):323-344
We introduce a quasi-isometry invariant related to Property A and explore its connections to various other invariants of finitely generated groups. This allows to establish a direct relation between asymptotic dimension on one hand and isoperimetry and random walks on the other. We apply these results to reprove sharp estimates on isoperimetric profiles of some groups and to answer some questions in dimension theory. 相似文献
997.
Vineet Kumar Rai 《Applied physics. B, Lasers and optics》2007,88(2):297-303
The dependence of temperature on the fluorescence lifetime and fluorescence intensity ratio using Stark sublevels and thermally
coupled (close lying) levels in triply ionized rare earth ions, doped into a variety of glasses and fibers, have been reviewed.
Also, it is claimed that not only for the two closely lying levels of triply ionized rare earth ion of the same kind, but
also for two different triply ionized rare earth ions, having their excited levels very close to each other, may be used to
monitor the temperature.
PACS 42.70.Ce 相似文献
998.
In previous work, we considered the representation of human decision-making processes in closed-form simulation models of conflict. An important element of this representation is the rapid planning process that embodies the processing of information for situation assessment to support a course of action decision (eg in a military headquarters). The application of this work is in support of operational analysis models for defence procurement and balance of investment. This paper describes the application of non-linear multi-attribute utility theory in conflict scenarios in order to extend the representation of the rapid planning process to account for a wider set of subjective attributes of the decision-maker. The results show, through examination of experimental data, that decision-making can be modelled through a particular class of utility functions. These utilities embody a geometry which allows us to classify the types of decision being made when there are conflicting objectives and when decision-makers adopt very different and subjective appraisals of constraints and beliefs in outcome. The experimental results help to demonstrate that the subjective nature of the situation assessment, and the personality, training, experience and history of the decision-maker are central to the functional representations. This paper presents a way to capture this deeper representation of human decision-making in a way that is potentially useful for quantitative modelling using the rapid planning process as a basis. 相似文献
999.
Physical aspects of an operation of the GaAs-based InGaAs/GaAs quantum-well (QW) VCSELs with the intentionally detuned optical
cavities have been considered in the present paper using the comprehensive three-dimensional self-consistent optical–electrical–thermal-gain
simulation. In GaAs-based structures, very good DBR resonator mirrors and a very efficient methods to confine radially both
the current spreading and the electromagnetic field with the aid of oxide apertures may be applied. It has been found using
the above simulation that even currently available immature technology enables manufacturing the above devices emitting radiation
of wavelengths over 1.20 μm. In particular, while the room-temperature 1.30-μm lasing emission is still beyond possibilities
of the InGaAs/GaAs QW VCSELs, these structures may offer analogous 1.25-μm emission, especially for the high-power and/or
high-temperature operation. 相似文献
1000.
F.T. Yuan S.K. Chen W.M. Liao C.W. Hsu S.N. Hsiao W.C. Chang 《Journal of magnetism and magnetic materials》2006
The Au/FePt samples were prepared by depositing a gold cap layer at room temperature onto a fully ordered FePt layer, followed by an annealing at 800 °C for the purpose of interlayer diffusion. After the deposition of the gold layer and the high-temperature annealing, the gold atoms do not dissolve into the FePt Ll0 lattice. Compared with the continuous FePt film, the TEM photos of the bilayer Au(60 nm)/FePt(60 nm) show a granular structure with FePt particles embedded in Au matrix. The coercivity of Au(60 nm)/FePt(60 nm) sample is 23.5 kOe, which is 85% larger than that of the FePt film without Au top layer. The enhancement in coercivity can be attributed to the formation of isolated structure of FePt ordered phase. 相似文献