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排序方式: 共有134条查询结果,搜索用时 281 毫秒
51.
Rokeya Akter Md. Habibur Rahman Deepak Kaushik Vineet Mittal Diana Uivarosan Aurelia Cristina Nechifor Tapan Behl Chenmala Karthika Manuela Stoicescu Mihai Alexandru Munteanu Cristiana Bustea Simona Bungau 《Molecules (Basel, Switzerland)》2021,26(17)
Extensive experimental, clinical, and epidemiological evidence has explained and proven that products of natural origin are significantly important in preventing and/or ameliorating various disorders, including different types of cancer that researchers are extremely focused on. Among these studies on natural active substances, one can distinguish the emphasis on resveratrol and its properties, especially the potential anticancer role. Resveratrol is a natural product proven for its therapeutic activity, with remarkable anti-inflammatory properties. Various other benefits/actions have also been reported, such as cardioprotective, anti-ageing, antioxidant, etc. and its rapid digestion/absorption as well. This review aims to collect and present the latest published studies on resveratrol and its impact on cancer prevention, molecular signals (especially p53 protein participation), and its therapeutic prospects. The most recent information regarding the healing action of resveratrol is presented and concentrated to create an updated database focused on this topic presented above. 相似文献
52.
M. -I. Munteanu 《Acta Mathematica Hungarica》2007,116(1-2):121-126
Warped product C R-submanifolds in Kählerian manifolds were intensively studied only since 2001 after the impulse given by B. Y. Chen in [3], [4]. Immediately after, another line of research, similar to that concerning Sasakian geometry as the odd dimensional version of Kählerian geometry, was developed, namely warped product contact C R-submanifolds in Sasakian manifolds (cf. [7], [8]). In this note we prove that there exists no proper doubly warped product contact C R-submanifolds in trans-Sasakian manifolds. 相似文献
53.
Andreea Munteanu Emilia Petrisor Enrique García-Berro Jordi Jos 《Communications in Nonlinear Science & Numerical Simulation》2003,8(3-4):355
In the present paper, we study the Poincaré map associated to a periodic perturbation, both in space and time, of a linear Hamiltonian system. The dynamical system embodies the essential physics of stellar pulsations and provides a global and qualitative explanation of the chaotic oscillations observed in some stars. We show that this map is an area preserving one with an oscillating rotation number function. The nonmonotonic property of the rotation number function induced by the triplication of the elliptic fixed point is superposed on the nonmonotonic character due to the oscillating perturbation. This superposition leads to the co-manifestation of generic phenomena such as reconnection and meandering, with the nongeneric scenario of creation of vortices. The nonmonotonic property due to the triplication bifurcation is shown to be different from that exhibited by the cubic Hénon map, which can be considered as the prototype of area preserving maps which undergo a triplication followed by the twistless bifurcation. Our study exploits the reversibility property of the initial system, which induces the time-reversal symmetry of the Poincaré map. 相似文献
54.
55.
Shelly John Mechery Xiaojun Julia Zhao Lin Wang LisaR. Hilliard Alina Munteanu Weihong Tan 《化学:亚洲杂志》2006,1(3):384-390
A simple and portable flow channel optical detection system combined with bioconjugated luminescent nanoparticles allows the rapid detection of single bacterial cells without sample enrichment. The optical system is designed to have single‐molecule‐detection capability in a microcapillary flow channel by decreasing the laser excitation probe volume to a few picoliters, which consequently results in a low background. Specific monoclonal antibodies were immobilized on nanoparticles to form nanoparticle–antibody conjugates. The bioconjugated nanoparticles bind to the target bacteria when they recognize the antigen on the bacterium surface, thus providing a bright luminescent signal for the detection of individual bacteria cells. The high sensitivity provided by the luminescent and photostable silica nanoparticles eliminates the need for further enrichment of bacteria samples and signal amplification. This flow channel detection system is convenient and allows the detection of single bacterial cells within a few minutes. 相似文献
56.
With the example of the determination of Tl(I) with a mercury-carbon electrode generated in situ on a carbon fiber substrate, it is shown that an electrode with a monolayer thickness of the mercury film reduces the quantification limit of the metal as compared to the electrode with a thick mercury film (down to 10?10 M). Studying the electrooxidation kinetics of Tl (Zn, Cd, Pb) showed that the rate constant and the transport coefficient at this electrode are independent of the electrode polarization rate. It is found that the rate constant of the electrode process and the slope of the calibration plot linearly depend on the atomic radius of the metal under study. 相似文献
57.
Summary A scheme was devised for the identification of 22 common antioxidants and light-stabilisers in polyolefins. The separation of these stabilisers was performed by isocratic reversed phase high-performance liquid chromatography on a RP-18 column. Three different separation conditions have been used: the mobile phase composition was 100% acetonitrile (MeCN), 90/10 meCN/H2O and 80/20 MeCN/H2O. The UV254/UV280 ratio and the elution time of each stabiliser were determined for these three mobile phase compositions. The values of UV254/UV280 ratios may be used together with the retention time values for the identification of unknown stabilisers in polyolefin samples. 相似文献
58.
Marian-Ioan Munteanu 《Czechoslovak Mathematical Journal》2008,58(1):61-78
In this paper we obtain all invariant, anti-invariant and CR submanifolds in (?4, g, J) endowed with a globally conformal Kähler structure which are minimal and tangent or normal to the Lee vector field of the g.c.K. structure. 相似文献
59.
Maricica Munteanu Soowhan Choi Helmut Ritter 《Journal of inclusion phenomena and macrocyclic chemistry》2008,60(3-4):197-202
The cyclic starches α-, β-, and γ-cyclodextrins (CDs) readily form inclusion complexes (ICs) with a large variety of polymers.
In polymer-CD-ICs, the CD hosts are threaded by the guest polymers, which must be highly extended, and stacks of polymer threaded
host CDs pack closely together and crystallize. When guest polymers are coalesced from their CD-IC crystals, by washing with
a solvent good, bad for CD, polymer, or treatment with an amylase enzyme, the guest polymers coalesce into bulk samples whose
structures, morphologies, and even conformations are distinct from bulk samples made from their solutions and melts. We generally
observe (i) crystallizable homopolymers coalesced from their CD-ICs to evidence increased levels of crystallinity, unusual
polymorphs, and higher melting, crystallization, and decomposition temperatures, while coalesced amorphous homopolymers exhibit
higher glass-transition temperatures, than samples consolidated from their disordered solutions and melts; (ii) molecularly
mixed, intimate blends of two or more polymers that are normally believed to be immiscible can be achieved by coalescence
from their common CD-IC crystals, (iii) the phase segregation of incompatible blocks can be controlled (suppressed or increased)
when block copolymers are coalesced from their CD-IC crystals, and (iv) the thermal and temporal stabilities of the coalesced
and well-mixed homopolymer blends and block copolymers appear to be substantial, thereby suggesting retention of as-coalesced
structures and morphologies under normal thermal processing conditions. Furthermore, CDs may be covalently incorporated in
polymers both during and after their syntheses, thereby providing a broad range of new functionalities for delivery of additives
or to act as sensors or filters. Alternatively, additive-CD-ICs or additives rotaxanated with CDs may be effectively delivered
to polymers. As an example, TiO2—filled polypropylene fibers may be readily dyed in aqueous solution using water soluble CD-rotaxanated azo-dyes. 相似文献
60.