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101.
102.
Agerdnio Andrade de Souza Brenda Lorena Snchez Ortíz Rosemary de Carvalho Rocha Koga Priscila Faimann Sales Divino Bruno da Cunha Ana Luiza Mantovaneli Guerra Gisele Custdio de Souza Jos Carlos Tavares Carvalho 《Molecules (Basel, Switzerland)》2021,26(24)
Plant-derived products may represent promising strategies in the treatment of Neglected Tropical Diseases (NTDs). From this perspective, it is observed that the Amazon phytogeographic region contains the tribe Canarieae of the Burseraceae family, composed of trees and shrubs supplied with resin channels. Its uses in folk medicine are related to aromatic properties, which have numerous medicinal applications and are present in reports from traditional peoples, sometimes as the only therapeutic resource. Despite its economic and pharmacological importance in the region, and although the family is distributed in all tropical and subtropical regions of the world, most of the scientific information available is limited to Asian and African species. Therefore, the present work aimed to review the secondary metabolites with possible pharmacological potential of the species Trattinnickia rhoifolia Willd, popularly known as “Breu sucuruba”. To this end, an identification key was created for chemical compounds with greater occurrence in the literature of the genus Trattinnickia. The most evident therapeutic activities in the consulted studies were antimicrobial, antioxidant, anti-inflammatory, antiviral, antifungal, anesthetic and antiparasitic. An expressive chemical and pharmacological relevance of the species was identified, although its potential is insufficiently explored, mainly in the face of the NTDs present in the Brazilian Amazon. 相似文献
103.
KM Clauwaert Van Bocxlaer JF HJ Major JA Claereboudt WE Lambert Van den Eeckhout EM Van Peteghem CH De Leenheer AP 《Rapid communications in mass spectrometry : RCM》1999,13(14):1540-1545
This paper describes the investigation of the potential of a quadrupole orthogonal acceleration time-of-flight mass spectrometer (Q-TOF) equipped with an atmospheric pressure ionisation interface for quantitative measurements of small molecules separated by reversed phase liquid chromatography. To this end, the detection limits and linear dynamic range in particular were studied in an LC/MS/MS experiment using 3,4-methylenedioxymethamphetamine standards and 3,4-methylenedioxyethylamphetamine for internal standardisation. In a second phase, the experiment was repeated with real biological extracts (whole blood, serum, and vitreous humour). A calibration for 3,4-methylenedioxymethamphetamine and its metabolite 3,4-methylenedioxyamphetamine was prepared in each of these matrices again using 3,4-methylenedioxyethylamphetamine as internal standard. The resulting quantitative data were compared with those obtained by liquid chromatography with fluorescence detection for the same extracts. The Q-TOF results revealed excellent sensitivity and a linear dynamic range of nearly four decades (2-10 000 pg on-column, r(2) = 0.9998, 1/x weighting). Furthermore, all the calibration curves prepared in biological material were superimposable, LC/MS/MS and LC-fluorescence, and the quantitative results for actual samples compared very favourably. It was concluded that the Q-TOF achieves a linear dynamic range for quantitative LC/MS/MS work exceeding that of fluorescence detection and at much better absolute sensitivity. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
104.
J.N. Tavares 《Journal of Geometry and Physics》1996,18(4):381-402
We show that the Classical Constraint Algebra of a Parametrized Relativistic Gauge System induces a natural structure of Conformal Foliation on a Transversal Gauge. Using the theory of conformal foliations, we provide a natural Factor Ordering for the quantum operators associated to the canonical quantization of such gauge system. 相似文献
105.
106.
107.
We consider a model for phase separation of a multi-componentalloy with a concentration-dependent mobility matrix and logarithmicfree energy. In particular we prove that there exists a uniquesolution for sufficiently smooth initial data. Further, we provean error bound for a fully practical piecewise linear finiteelement approximation in one and two space dimensions. Finallynumerical experiments with three components in one space dimensionare presented. 相似文献
108.
Low power laser radiation at 685 nm stimulates stem-cell proliferation rate in Dugesia tigrina during regeneration 总被引:1,自引:0,他引:1
de Souza SC Munin E Alves LP Salgado MA Pacheco MT 《Journal of photochemistry and photobiology. B, Biology》2005,80(3):203-207
Today’s scientific interest in tissue engineering for organ transplantations and regeneration from stem cells, allied with recent observations on biostimulation of tissues and cells by laser radiation, stands as a strong motivation for the present work, in which we examine the effects of the low power laser radiation onto planarians under regenerative process. To investigate those effects, a number of 60 amputated worms were divided in three study groups: a control group and two other groups submitted to daily 1 and 3 min long laser treatment sections at 910 W/m2 power density. A 685 nm diode laser with 35 mW optical power was used. Samples were sent to histological analysis at the 4th, the 7th and the 15th days after amputation. A remarkable increase in stem cells counts for the fourth day of regeneration was observed when the regenerating worms was stimulated by the laser radiation. Our findings encourage further research works on the influence of optical radiation onto stem cells and tissue regeneration. 相似文献
109.
Terashi K Tether S Theriot D Thurman-Keup R Tipton P Tkaczyk S Tollefson K Tollestrup A Toyoda H Trischuk W de Troconiz JF Tseng J Turini N Ukegawa F Vaiciulis T Valls J Vejcik S Velev G Vidal R Vilar R Volobouev I Vucinic D Wagner RG Wagner RL Wahl J Wallace NB 《Physical review letters》2000,85(22):4668-4673
An angular analysis of B0-->J/psiK(*0) and B(0)(s)-->J/psistraight phi has been used to determine the decay amplitudes with parity-even longitudinal ( A0) and transverse ( A( parallel)) polarization and parity-odd transverse ( A( perpendicular)) polarization. The measurements are based on 190 B0 and 40 B(0)(s) candidates obtained from 89 pb(-1) of &pmacr;p collisions at the Fermilab Tevatron. The longitudinal decay amplitude dominates with |A0|(2) = 0.59+/-0. 06+/-0.01 for B0 and |A0|(2) = 0.61+/-0.14+/-0.02 for B(0)(s) decays. The parity-odd amplitude is found to be small with |A( perpendicular)|(2) = 0.13(+0.12)(-0.09)+/-0.06 for B0 and |A( perpendicular)|(2) = 0.23+/-0.19+/-0.04 for B(0)(s) decays. 相似文献
110.
Trischuk W de Troconiz JF Tseng J Turini N Ukegawa F Vaiciulis T Valls J Vejcik S Velev G Vidal R Vilar R Volobouev I Vucinic D Wagner RG Wagner RL Wahl J Wallace NB Walsh AM Wang C Wang CH Wang MJ Watanabe T Waters D Watts T Webb R Wenzel H 《Physical review letters》2000,85(10):2062-2067
We use 106 pb (-1) of data collected with the Collider Detector at Fermilab to search for narrow-width, vector particles decaying to a top and an antitop quark. Model independent upper limits on the cross section for narrow, vector resonances decaying to t&tmacr; are presented. At the 95% confidence level, we exclude the existence of a leptophobic Z' boson in a model of top-color-assisted technicolor with mass M(Z')<480 GeV/c(2) for natural width gamma = 0.012M(Z'), and M(Z')<780 GeV/c(2) for gamma = 0.04M(Z'). 相似文献