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901.
Clinical research has demonstrated that large numbers of chemotherapy patients continue to experience nausea in the clinic prior to infusions. A better understanding of the mechanisms responsible for such anticipatory nausea (AN) is likely to provide critical information for identifying intervention targets. In the present study the authors investigated the contribution of expectancy, history of nausea, and distress to AN in 60 women with Stage I or II breast cancer receiving standard adjuvant chemotherapy. The predictors were each independently associated with AN (p 相似文献
902.
Abdalbasit A. Mariod Bertrand Matthäus & Ismail H. Hussein 《International Journal of Food Science & Technology》2008,43(5):921-926
The methanolic extracts from Sclerocarya birrea leaves (SCL), roots (SCR), barks (SCB), and kernel oil cake (SCK) were examined for radical scavenging capacities and antioxidant activities. The total phenolics of the extracts was determined spectrophotometrically according to the Folin‐Ciocalteau method using gallic acid as standard solution. The total phenolic compounds were found as 304.5, 367.5, 593, 148.0 and 258.0 mg g‐1 of dry product, respectively. The extracts of SCL, SCR, SCB and SCK were markedly effective in inhibiting the oxidation of linoleic acid and subsequent bleaching of β‐carotene in comparison with the control. Based on oxidation of β‐carotene/linoleic acid, the SCK extract is the most effective followed by SCR, SCL and SCB extract. The antioxidant activity determined by the DPPH (1,1‐diphenyl‐β‐picrylhydrazyl) method revealed that the SCK extract had the highest antioxidant activity on DPPH free radicals followed by SCB, SCR and SCL extracts. The effect of different extracts on the oxidative stability of sunflower oil at 70 °C was tested in the dark and compared with BHA. The oil peroxide values (PVs) were generally lower with the addition of extract in comparison to a control. 相似文献
903.
Andrieu J. Nouvet S. Bertrand V. Beillard B. Jecko B. 《Antennas and Propagation, IEEE Transactions on》2005,53(4):1254-1261
A new ultrawide-band (UWB) antenna named the "scissors antenna" has been designed specially for transient ultrawide-band applications. The scissors antenna, which is composed of conducting wires, radiates ultrashort pulses with very low dispersion. The radiation of this antenna has been characterized by a transient measurement method suitable for characterizing UWB antennas with very low dispersion. After a presentation of the scissors antenna, this measurement method is described. The last part of the paper presents a comparison between the radiation characteristics of the scissors antenna obtained by the transient measurements and those obtained by the classical harmonic measurements. 相似文献
904.
Le Guyadec E. Coutance P. Bertrand G. Peltier C. 《Quantum Electronics, IEEE Journal of》1999,35(11):1616-1622
A large-volume (19.5 L) laser tube has been built for the study of extrapolating power from the Cu-Ne-HBr laser medium. A high-power (50 kW) all-solid-state power supply has been also developed for this purpose. Results show a record optical power of 216 W extracted from this type of laser when used as an oscillator and 280 W as an amplifier 相似文献
905.
C Chiabrando A Valagussa C Rivalta T Durand A Guy E Zuccato P Villa JC Rossi R Fanelli 《Canadian Metallurgical Quarterly》1999,274(3):1313-1319
F2-isoprostanes are prostaglandin-like compounds derived from nonenzymatic free radical-catalyzed peroxidation of arachidonic acid. 8-epi-Prostaglandin (PG) F2alpha, a major component of the F2-isoprostane family, can be conveniently measured in urine to assess noninvasively lipid peroxidation in vivo. Measurement of major metabolites of endogenous 8-epi-PGF2alpha, in addition to the parent compound, may be useful to better define its formation in vivo. 2,3-Dinor-5,6-dihydro-8-epi-PGF2alpha is the only identified metabolite of 8-epi-PGF2alpha in man, but its endogenous levels are unknown. In addition to this metabolite, we have identified another major endogenous metabolite, 2,3-dinor-8-epi-PGF2alpha, in human and rat urine. The identity of these compounds, present at the pg/ml level in urine, was proven by a number of complementary approaches, based on: (a) immunoaffinity chromatography for selective extraction; (b) gas chromatography-mass spectrometry for structural analysis; (c) in vitro metabolism in isolated rat hepatocytes; and (d) chemical synthesis of the enantiomer of 2,3-dinor-5, 6-dihydro-8-epi-PGF2alpha as a reference standard. In humans, the urinary excretion rate of both dinor metabolites is comparable with that of 8-epi-PGF2alpha. Both metabolites increase in parallel with the parent compound in cigarette smokers, and they are not reduced during cyclooxygenase inhibition. Another beta-oxidation product, 2, 3,4,5-tetranor-8-epi-PGF2alpha, was identified as a major product of rat hepatocyte metabolism. In conclusion, at least two major beta-oxidation products of 8-epi-PGF2alpha are present in urine, which may be considered as additional analytical targets to evaluate 8-epi-PGF2alpha formation and degradation in vivo. 相似文献
906.
Representation of film texts for scholars and students has been fraught with difficulties imposed by the very nature of the text. The time-varying image track presented hurdles to close significant challenges to formulation of units of meaning and analysis. The digital environment offers opportunities for addressing these problems. We offer here a model of the film document as a bundle of time-varying signals. We demonstrate using this model to construct a system for close analysis of film texts, including precise measurement of attributes. Finally, we consider some consequence for the pedagogical environment. 相似文献
907.
908.
Bertrand Emmanuel Castany Philippe Yang Yang Menou Edern Couturier Laurent Gloriant Thierry 《Journal of Materials Science》2022,57(14):7327-7342
Journal of Materials Science - $${\left\{112\right\}\langle {111}\rangle }_{\beta }$$ twins are observed in a superelastic β Ti-24Nb-4Zr-8Sn (wt.%) single crystal after tensile test. A careful... 相似文献
909.
The rationalization of various aspects of the mechanism of chirality induction in supramolecular assemblies based upon the complexes formed between an ethane-linked bisoctaethylporphyrin and chiral ligands is described. The influence of various controlling factors such as bonding strength, host-guest steric interactions, equilibria and thermodynamic parameters, temperature and solvent effects, role of the center metal ion, stoichiometry, and phase transition on the chirality induction processes have been investigated, and the results and implications are discussed. As a result of such detailed understanding, it is possible to employ this bisporphyrin system as an effective chirality sensor for the determination of absolute configuration. 相似文献
910.