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排序方式: 共有206条查询结果,搜索用时 15 毫秒
51.
Renata leite Tavares Maria Helena Araújo de Vasconcelos Maria Letícia da Veiga Dutra Aline Barbosa DOliveira Marcos dos Santos Lima Mirian Graciela da Silva Stiebbe Salvadori Ramon de Alencar Pereira Adriano Francisco Alves Yuri Mangueira do Nascimento Josean Fechine Tavares Omar Guzman-Quevedo Jailane de Souza Aquino 《Molecules (Basel, Switzerland)》2020,25(23)
This study evaluated the effect of Mucuna pruriens (MP) administration on neuroinflammation and behavioral and murinometric parameters in obese rats. Proximate composition, oligosaccharide and phenolic compound profile of MP were determined. Wistar adult male rats were randomized into healthy (HG) and obese group (OG). The HG consumed a control chow diet while OG consumed a cafeteria diet for eight weeks. Then, they were subdivided into: Healthy (HG); Healthy with MP administration (HGMP); Obese (OG); Obese with MP administration (OGMP), with the consumption of the respective diets remaining for another eight weeks, in addition to gavage with MP extract to supplemented groups (750 mg/kg weight). MP presented a composition rich in proteins and phenolic compounds, especially catechin, in addition to 1-kestose and levodopa. Supplementation reduced food intake, body weight, and thoracic and abdominal circumferences in obese rats. MP showed anxiolytic and antidepressant effects and reduced morphological damage and expression of interleukin 6 in the hippocampus of obese rats. MP treatment showed satietogenic, slimming, anxiolytic and antidepressant effects, besides to minimizing hippocampal neuroinflammation in obese rats. Our results demonstrated the potential anti-obesity of MP which are probably related to the high content of bioactive compounds present in this plant extract. 相似文献
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A. J. A. Aquino L. A. Soares II A. B. F. Da Silva M. Trsic 《Journal of Molecular Structure》1986,139(3-4):327-332
Semiempirical MNDO calculations are performed on various models for the polythiazyl polymer with increasing chain sizes. Population analysis, geometry optimization and the evolution of the frontier orbital energies are discussed. A low-lying broken symmetry structure with (SN)2 repeating units is detected. 相似文献
58.
Antonio?S.?AraújoEmail author Marcelo?J.?B.?Souza Antonio?O.?S.?Silva Anne?M.?G.?Pedrosa Joana?M.?F.?B.?Aquino Ana?C.?S.?L.?S.?Coutinho 《Adsorption》2005,11(2):181-186
The variation of surface properties of SiMCM-41 and AlMCM-41 nanoporous materials as function of synthesis time was examined.
The main properties studied were: surface area, pore diameter, pore volume, mesoporous parameter, and wall thickness. Siliceous
MCM-41 molecular sieves were synthesized starting from hydrogels with the following molar compositions: 4.58SiO2:0.435Na2O:1 CTMABr:200 H2O for SiMCM-41, and 4.58SiO2:0.485 Na2O:1 CTMABr:0.038 Al2O3:200 H2O, for AlMCM-41. Cetyltrimethylammonium bromide (CTMABr) was used as the structural template. The crystallographic parameters
were obtained from XRD data and by nitrogen adsorption using the BET and BJH methods. The results obtained showed a significant
variation of the surface properties of the MCM-41 materials as a function of the synthesis time reaching silica wall thickness
of ca. 2 nm on the fourth day. 相似文献
59.
Antonio?S.?AraujoEmail author Antonio?O.?S.?Silva Marcelo?J.?B.?Souza Ana?C.?S.?L.?S.?Coutinho Joana?M.?F.?B.?Aquino José?A.?Moura Anne?M.?G.?Pedrosa 《Adsorption》2005,11(2):159-165
In this work the acid properties of a series of HZSM-12 zeolites with different Si/Al ratio were studied. The ZSM-12 crystals
were synthesized by the hydrothermal method starting from a gel with the following molar composition: 20MTEA:10Na2O:x Al2O3:100SiO2:2000H2O, with x = 0.50, 0.67, 1, 1.25 and 2, respectively. The gels were crystallized at 140∘C for 6 days, then washed, dried and calcined to remove the MTEA template. The samples were ion-exchanged with an ammonium
chloride solution and calcined again to obtain the zeolites in the acid form. The materials thus obtained were characterized
by XRD, SEM, BET, TG and n-butylamine adsorption. The Si/Al ratio in the reaction mixture affects the amount of zeolite produced and the size of the
particles. The XRD analysis indicated that the ZSM-12 zeolite crystallizes in a pure form only with Si/Al ratio above 33.
The SEM analysis showed the presence of crystallites with very well defined prismatic shapes. The removal of the MTEA of the
pores of the ZSM-12 by TG indicated that there are two kinds of internal sites occupied by MTEA inside the structure. The
BET area of the ZSM-12 decreases proportionally with the crystallinity of materials. The desorption of n-butylamine showed
that the acid site density is proportional to aluminum content, but the Si/Al ratio shows little influence on the relative
strengths of these sites. 相似文献
60.
Chidthong R Hannongbua S Aquino AJ Wolschann P Lischka H 《Journal of computational chemistry》2007,28(10):1735-1742
The structural and electronic properties of the fluorene-pyridine copolymer (FPy)(n), (n = 1-4) were investigated theoretically by means of quantum mechanical calculations based on density functional theory (DFT) and time-dependent DFT (TD-DFT) using the B3LYP functional. Geometry optimizations of these oligomers were performed for the ground state and the lowest excited state. It was found that (FPy)(n) is nonplanar in its ground state, whereas a more pronounced trend toward planarity is observed in the S(1) state. Absorption and fluorescence energies have been extrapolated to infinite chain length making use of their good linearity with respect to 1/n. An extrapolated value of 2.64 eV is obtained for vertical excitation energy. The S(1)<--S(0) electronic excitation is characterized as a highest occupied molecular orbital to lowest unoccupied molecular orbital transition and is dominating in terms of oscillator strength. Fluorescence energies and radiative lifetime were calculated as well. The obtained results indicate that the fluorescence energy and radiative lifetime of (FPy)(n) are 2.16 eV and 0.38 ns, respectively. The decrease of fluorescence energy and radiative lifetime with the increase in the chain length is discussed. 相似文献