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431.
432.
Babajan Banaganapalli Chaitanya Mulakayala Gowsia D Naveen Mulakayala Madhusudana Pulaganti Noor Ahmad Shaik Anuradha CM Raja Mohan Rao Jumana Yousuf Al-Aama Suresh Kumar Chitta 《Applied biochemistry and biotechnology》2013,171(7):1639-1657
Resveratrol (RVS) is a naturally occurring antioxidant, able to display an array of biological activities. In the present investigation, a new derivative of RVS, RVS(a), was synthesized, and its biological activity was determined on U937 cells. It was observed that RVS(a) showed pronounced activity on U937 cells than RVS. RVS(a) is able to induce apoptosis in tumor cell lines through subsequent DNA fragmentation. From the EMSA results, it was evident that RVS(a) was able to suppress the activity of NFkB by interfering its DNA binding ability. Furthermore, the molecular interaction analysis (docking and dynamics) stated that RVS(a) has strong association with the IkB-alpha site of NFkB compared with RVS; this binding nature of RVS(a) might be prevent the NFkB binding ability with DNA. The present findings represent the potential activity of propynyl RVS on U937 cells and signifying it as a one of putative chemotherapeutic drugs against cancer. 相似文献
433.
Reaction of 2-trifluoromethyl- (1) and 2,2-bis(trifluoromethyl)- (2) oxiranes with a variety of sulfur nucleophiles proceeds rapidly and under mild conditions. For example, epoxide 2 reacts with aqueous solution of Na2S, producing S[CH2C(CF3)2OH]2. Reaction of 2 with Na2S2O3 leads to the formation of the corresponding Bunte salt. Interaction of 2 with NaSCN in water proceeds exothermically and results in high-yield formation of cyclic imine 5. Although this material can be isolated, it has limited stability and undergoes cyclotrimerization at ambient temperature, giving the corresponding 1,3,5-triazine. A number of heterocyclic compounds containing pendant -CH2C(CF3)2OH group were prepared by the reaction of the corresponding thio-derivatives, such as pyridine-2-thiole with epoxide 2. It was found that fluoride anion catalyzes the reaction of epoxides 1 and 2 with isothiocyanates carrying electron withdrawing groups at nitrogen. The reaction results in nucleophilic cyclization and formation of the corresponding exocyclic imines containing a 1,3-oxothiolane moiety. Carbon disulfide was also found to be active in this process, reacting with epoxides 1 and 2 at ambient to give the corresponding trifluoromethylated 1,3-oxathiolane-2-thiones in 58-65% yield. 相似文献
434.
Honglei Li Will Parker Zongguo Si Shufang Su 《The European Physical Journal C - Particles and Fields》2011,71(3):1584
The experimental search limit on the Higgs boson mass points to a “golden region” in the Minimal Supersymmetric Standard Model parameter space in which the fine-tuning in the electroweak sector is minimized. One of the sbottoms is relatively light since its mass parameter is related to that of the stop. The decay products of the light sbottom typically include a W boson and a b jet. We studied the pair production of the light sbottoms at the Large Hadron Collider and examined its discovery potential via collider signature of 4 jets + 1 lepton + missing E T . Such channel differs from conventional sbottom searches of either \(\tilde{b}_{1} \rightarrow b \chi_{2}^{0} \rightarrow b \ell^{+}\ell^{-} \chi_{1}^{0}\) or \(\tilde{b}_{1} \rightarrow t \chi_{1}^{-}\) with reconstructed top quark. We analyzed the Standard Model backgrounds for this channel and developed a set of cuts to identify the signal and suppress the backgrounds. We showed that with 100 fb?1 integrated luminosity, a significance level of 5–6 σ could be reached for the light sbottom discovery at the LHC. 相似文献
435.
Nasim Alem Rolf Erni Christian Kisielowski Marta D. Rossell Peter Hartel Bin Jiang Will Gannett A. Zettl 《固体物理学:研究快报》2011,5(8):295-297
Atomically thin hexagonal boron nitride (h‐BN) is investigated using aberration‐corrected ultra‐high resolution electron microscopy under 80 kV electron beam. This study focuses on the in situ formation, growth and migration of vacancies in h‐BN. This study also reveals interaction dynamics of edges and vacancies with adatoms and molecules under the electron beam. According to this investigation, boron monovacancies migrate through their second neighbor to reduce the surface energy of the membrane. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
436.
Marijke WA de Backer Maike AD Brans Mieneke CM Luijendijk Keith M Garner Dianne MA van den Heuvel R Jeroen Pasterkamp Roger AH Adan 《BMC neuroscience》2010,11(1):94
Background
Multiple neuropeptides, sometimes with opposing functions, can be produced from one precursor gene. To study the roles of the different neuropeptides encoded by one large precursor we developed a method to overexpress minigenes and establish local secretion. 相似文献437.
Suppose that R is a local domain with fraction field K. If R is Henselian, then the R-adic topology over K refines the étale open topology. If R is regular, then the étale open topology over K refines the R-adic topology. In particular, the étale open topology over agrees with the -adic topology for any field L and . 相似文献
438.
The unit cell parameters of this compound were determined by least-squares calculations from the adjusted angular setting of 25 general reflections. The crystals are monoclinic with the following crystallographic data: a = 5.718(1), b = 13.794(4), c = 7.861(1) Å, β = 100.53(2)°, Z = 2 and Dx = 1.34 g · cm−3. The space group according to the systematic absences is P21. The structure of this compound was solved by direct methods and refined by full matrix least-squares with anisotropic temperature factors to R = 0.04. The refined atomic positions indicate a considerable strain within the molecule. The structure is built up from molecules connected by H-atoms forming infinite chains along b-axis. 相似文献
439.
Will Johnson 《Mathematical Logic Quarterly》2023,69(1):50-57
Let G be a definable group in a p-adically closed field M. We show that G has finitely satisfiable generics () if and only if G is definably compact. The case was previously proved by Onshuus and Pillay. 相似文献
440.