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101.
Norbil Cordova Denise de Mattos Edivaldo L. dos Santos 《Journal of Fixed Point Theory and Applications》2013,13(1):163-173
Yasuhiro Hara in [Topology Appl. 148 (2005), 113–121] and Jan Jaworowski in [J. Fixed Point Theory Appl. 1 (2007), 111–121] studied, under certain conditions, the degree of equivariant maps between free G-manifolds, where G is a compact Lie group. The main results obtained by them involve data provided by the classifying maps of the orbit spaces. In this paper, we extend these results by replacing the free G-manifolds by free generalized G-manifolds over ${\mathbb{Z}}$ . 相似文献
102.
Camila Rodrigues Ferraz Denise Brentan Silva Ligia Carolina da Silva Prado Hudson Armando Nunes Canabrava 《Natural product research》2019,33(4):563-567
We investigated the antidiarrhoeic effect of the aqueous extract of Annona crassiflora leaves (AEAC). The AEAC decreased the diarrhoeic stools and enteropooling induced by castor oil, without altering total faecal output; moreover, the distance travelled by charcoal meal in the intestine was increased. Twenty-eight compounds were identified by LC-DAD-MS in the AEAC, including flavonoids, alkaloids and proanthocyanidins. In addition, two oligomeric series of condensed tannins of up to nine flavan-3-ol units were characterised by MALDI-MS. These data suggest that the antidiarrhoeic effect of the AEAC is related to its ability to inhibit intestinal secretion and/or to increase intestinal absorption. Moreover, the prokinetic effect of AEAC, together with its inhibitory effect on enteropooling induced by castor oil, explains why this extract decreased diarrhoeic faeces without altering the total faecal output. All these effects are in agreement with the pharmacological activity reported in the literature for many of the secondary metabolites identified. 相似文献
103.
Fernando Silveira Denise Santos de Sá Zênis Novais da Rocha Maria do Carmo Martins Alves João Henrique Zimnoch dos Santos 《X射线光谱测定》2008,37(6):615-624
A series of metallocenes, namely, [Cp2ZrCl2], [(MeCp)2ZrCl2], [(nBuCp)2ZrCl2], [(iBuCp)2ZrCl2], [(tBuCp)2ZrCl2], [Et(Ind)2ZrCl2], [Et(IndH4)2ZrCl2], and [MeSi2(Ind)2ZrCl2)] were analyzed by extended x‐ray absorption fine structure (EXAFS) and x‐ray photoelectron spectroscopy (XPS). Complementary techniques, UV–vis spectroscopy and cyclic and differential pulse voltammetry, were employed to characterize the organometallic complexes. The catalysts were evaluated in ethylene polymerization, having methylaluminoxane (MAO) as the cocatalyst, and the resulting polymers were characterized by gel permeation chromatography. The structural and electronic effects caused by the coordination sphere around the metal center and their effects on the catalytic activity and polymer characteristics are discussed. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
104.
Denise Utami Putri Ning Rintiswati Sofia Mubarika Haryana 《Natural product research》2018,32(4):463-467
Disease progression in Tuberculosis (TB) is dependent on host’s immune system. Phyllanthus niruri, a traditional herb, has long been used to boost immune system in Indonesian society. This study aimed to observe the potential role of P. niruri in inducing immune cells activity in TB patients by in vitro approach. Peripheral blood mononuclear cells (PBMCs) and macrophages were collected from active pulmonary TB patients. After stimulation with graded doses of P. niruri aqueous extract, cell proliferation, phagocytic activity and nitric oxide (NO) release were analysed. P. niruri aqueous extract induced proliferation of PBMCs, increased NO release, and improved macrophages phagocytic activity. These effects were observed in a dose-dependent manner. This may lead to further research for the potential role of P. niruri as immunomodulatory adjuvant therapy for TB patients. 相似文献
105.
L. Semichon M. Flanzy A. Boidin E. Martin A. Wanscheidt O. Ieremejewa Al. Ionescu-Matiu Const Popesco H. S. King A. C. Bell C. Kollo N. Crisan G. Klein H. Linser O. Noetzel F. M. Archibald C. M. Beamer I. M. Korenman L. Palfray S. Sabetay Denise Sontag M. C. Brockmann C. H. Werkman C. Neuberg F. F. Nord C. R. Breden E. I. Fulmer L. Malaprade J. H. Birkinshaw J. H. V. Charles P. W. Clutterbuck C. B. van Niel K. Száhlender 《Analytical and bioanalytical chemistry》1934,97(5-6):210-220
106.
107.
Wallans Torres Pio dos Santos Edimar Gledison Nascimento de Almeida Humberto Eustáquio Alves Ferreira Denise Tofanello Gimenes Eduardo Mathias Richter 《Electroanalysis》2008,20(17):1878-1883
The present work reports a simple and quick strategy for simultaneous determination of paracetamol (PC) and ascorbic acid (AA) in pharmaceutical formulations using flow injection method with multiple pulse amperometric detection. The method allows the resolution of the mixture without chemical pretreatment of the sample or electrode modification or the use of chemometric techniques for data analysis. The compounds are detected by applying four sequential pulses (waveform) in function of time to a three‐electrode amperometric system that uses a wall‐jet cell with gold as working electrode. AA is direct detected at +0.40 V and PC is indirectly detected at 0.0 V by the reduction (desorption) of the oxidation product (N‐acetyl‐p‐benzoquinoneimine) electrochemically generated at +0.65 V. The fourth potential pulse (?0.05 V) is applied for the complete regeneration (cleaning) of the gold electrode surface. The linear response range was optimized between 5 and 24 mg L?1 for AA and 50 and 240 mg L?1 for PC. The difference between the two responses ranges (10‐fold) present correlation with the concentration of these compounds in two different pharmaceutical formulations available in the Brazilian market. The analytical frequency was calculated in 60 injections per hour. The use of the proposed methodology for PC quantification in the presence of higher AA concentrations was also carried out. Using the standard addition method, it was possible to detect PC in trace levels (LD=0.2 mg L?1) in the presence of 880‐fold more of AA (176 mg L?1). 相似文献
108.
Pereira EM Sierakowski MR Jó TA Moreira RA Monteiro-Moreira AC França RF Fonseca BA Petri DF 《Colloids and surfaces. B, Biointerfaces》2008,66(1):45-52
Formation of stable thin films of mixed xyloglucan (XG) and alginate (ALG) onto Si/SiO(2) wafers was achieved under pH 11.6, 50mM CaCl(2), and at 70 degrees C. XG-ALG films presented mean thickness of (16+/-2)nm and globules rich surface, as evidenced by means of ellipsometry and atomic force microscopy (AFM), respectively. The adsorption of two glucose/mannose-binding seed (Canavalia ensiformis and Dioclea altissima) lectins, coded here as ConA and DAlt, onto XG-ALG surfaces took place under pH 5. Under this condition both lectins present positive net charge. ConA and DAlt adsorbed irreversibly onto XG-ALG forming homogenous monolayers approximately (4+/-1)nm thick. Lectins adsorption was mainly driven by electrostatic interaction between lectins positively charged residues and carboxylated (negatively charged) ALG groups. Adhesion of four serotypes of dengue virus, DENV (1-4), particles to XG-ALG surfaces were observed by ellipsometry and AFM. The attachment of dengue particles onto XG-ALG films might be mediated by (i) H bonding between E protein (located at virus particle surface) polar residues and hydroxyl groups present on XG-ALG surfaces and (ii) electrostatic interaction between E protein positively charged residues and ALG carboxylic groups. DENV-4 serotype presented the weakest adsorption onto XG-ALG surfaces, indicating that E protein on DENV-4 surface presents net charge (amino acid sequence) different from E proteins of other serotypes. All four DENV particles serotypes adsorbed similarly onto lectin films adsorbed. Nevertheless, the addition of 0.005mol/L of mannose prevented dengue particles from adsorbing onto lectin films. XG-ALG and lectin layers serve as potential materials for the development of diagnostic methods for dengue. 相似文献
109.
110.
The efficient on/off switching of fluorescence from thienyl- and phenyl-substituted porphyrin-ferrocene dyads is achieved through redox control of excited-state electron-transfer quenching. 相似文献