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71.
Mohammed I. El-Gamal Nada H. Mewafi Nada E. Abdelmotteleb Minnatullah A. Emara Hamadeh Tarazi Rawan M. Sbenati Moustafa M. Madkour Seyed-Omar Zaraei Afnan I. Shahin Hanan S. Anbar 《Molecules (Basel, Switzerland)》2021,26(23)
HER4 is a receptor tyrosine kinase that is required for the evolution of normal body systems such as cardiovascular, nervous, and endocrine systems, especially the mammary glands. It is activated through ligand binding and activates MAPKs and PI3K/AKT pathways. HER4 is commonly expressed in many human tissues, both adult and fetal. It is important to understand the role of HER4 in the treatment of many disorders. Many studies were also conducted on the role of HER4 in tumors and its tumor suppressor function. Mostly, overexpression of HER4 kinase results in cancer development. In the present article, we reviewed the structure, location, ligands, physiological functions of HER4, and its relationship to different cancer types. HER4 inhibitors reported mainly from 2016 to the present were reviewed as well. 相似文献
72.
Hanan E. Abdou Ahmed A. Mohamed José M. López-de-Luzuriaga John P. FacklerJr. 《Journal of Cluster Science》2004,15(4):397-411
The syntheses and characterization of gold(I) naphthyl, pentafluorophenyl, and trifluoromethylphenyl amidinate complexes are reported. The tetranuclear clusters are obtained from the reaction of Au(tetrahydrothiophene)Cl with the potassium salt of the corresponding amidinate in a THF solvent. The crystal structures of the gold(I) naphthyl, 2, and pentafluorophenyl, 3, amidinates show a short Au···Au distance of ~3. 0 Å typical of compounds having an aurophilic interaction. The gold atoms are arranged in a square (Au···Au···Au = 87°–92°) in the pentafluorophenyl derivative and in a parallelogram (Au···Au···Au = 68°–110°) in the naphthyl amidinate complexes. The naphthyl and trifluoromethylphenyl complexes are visibly luminescent in the solid state at liquid nitrogen temperature displaying asymmetric emission bands at 538 and 473 nm, respectively. The luminescent lifetimes of these species are in the millisecond range indicating phosphorescent processes. 相似文献
73.
Clay‐supported copper(II) nitrate (claycop) has been used as an efficient catalyst for azide–alkyne cycloaddition reactions leading to 1,4‐disubstituted 1,2,3‐triazoles. The highly efficient claycop/hydrazine hydrate catalytic system affords triazoles in a few minutes (1–20 min) at room temperature, under mild and solvent‐free conditions. High regioselectivity, excellent yields, ease of claycop synthesis and recyclability/reusability of the catalyst are considered as practical merits of the protocol. 相似文献
74.
Hanan F. Abd El-Halim F. A. Nour El-Dien Gehad G. Mohamed Nehad A. Mohamed 《Journal of Thermal Analysis and Calorimetry》2013,111(1):173-181
New seven metal complexes of tioconazole drug with the general formulae [MCl2(L)2(H2O)x].yH2O (where, x = 0 and y = 1 for M = Mn(II) or x = 2, y = 2 for M = Co(II)), and x = 0, y = 3 for M = Cu(II), Ni(II), Zn(II)) and [MCl2(L)2(H2O)2]Cl.3H2O (where M = Cr(III) and Fe(III)) have been prepared and characterized based on elemental analyses, IR, magnetic moment, molar conductance, and thermal analyses techniques. From molar conductance data bivalent metal chelates are non-electrolytes while Cr(III) and Fe(III) chelates are electrolytes and of 1:1 type. According to the IR spectral data, TCNZ is coordinated to the metal ions in a neutral unidentate manner with N donor site of the imidazole–N. All the complexes are octahedral except Mn(II) complex has tetrahedral structure. TCNZ drug and its metal complexes were also screened for their biological activity. 相似文献
75.
76.
Biller JR Meyer V Elajaili H Rosen GM Kao JP Eaton SS Eaton GR 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2011,212(2):370-377
Optimization of nitroxides as probes for EPR imaging requires detailed understanding of spectral properties. Spin lattice relaxation times, spin packet line widths, nuclear hyperfine splitting, and overall lineshapes were characterized for six low molecular weight nitroxides in dilute deoxygenated aqueous solution at X-band. The nitroxides included 6-member, unsaturated 5-member, or saturated 5-member rings, most of which were isotopically labeled. The spectra are near the fast tumbling limit with T1∼T2 in the range of 0.50–1.1 μs at ambient temperature. Both spin–lattice relaxation T1 and spin–spin relaxation T2 are longer for 15N- than for 14N-nitroxides. The dominant contributions to T1 are modulation of nitrogen hyperfine anisotropy and spin rotation. Dependence of T1 on nitrogen nuclear spin state mI was observed for both 14N and 15N. Unresolved hydrogen/deuterium hyperfine couplings dominate overall line widths. Lineshapes were simulated by including all nuclear hyperfine couplings and spin packet line widths that agreed with values obtained by electron spin echo. Line widths and relaxation times are predicted to be about the same at 250 MHz as at X-band. 相似文献
77.
We study reflection of optically spin-oriented hot electrons as a means to probe the semiconductor crystal symmetry and its intimate relation with the spin-orbit coupling. The symmetry breaking by reflection manifests itself by tipping the net-spin vector of the photoexcited electrons out of the light propagation direction. The tipping angle and the pointing direction of the net-spin vector are set by the crystal-induced spin precession, momentum alignment, and spin-momentum correlation of the initial photoexcited electron population. We examine nonmagnetic semiconductor heterostructures and semiconductor-ferromagnet systems and show the unique signatures of these effects. 相似文献
78.
Inside Cover: Stoichiometrically Controlled Revocable Self‐Assembled “Spiro” versus Quadruple‐Stranded “Double‐Decker” Type Coordination Cages (Chem. Eur. J. 41/2014)
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79.
Stoichiometrically Controlled Revocable Self‐Assembled “Spiro” versus Quadruple‐Stranded “Double‐Decker” Type Coordination Cages
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Sreenivasulu Bandi Dr. Amlan K. Pal Prof. Dr. Garry S. Hanan Prof. Dr. Dillip Kumar Chand 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(41):13122-13126
The simple combination of PdII with the tris‐monodentate ligand bis(pyridin‐3‐ylmethyl) pyridine‐3,5‐dicarboxylate, L , at ratios of 1:2 and 3:4 demonstrated the stoichiometrically controlled exclusive formation of the “spiro‐type” Pd1L2 macrocycle, 1 , and the quadruple‐stranded Pd3L4 cage, 2 , respectively. The architecture of 2 is elaborated with two compartments that can accommodate two units of fluoride, chloride, or bromide ions, one in each of the enclosures. However, the entry of iodide is altogether restricted. Complexes 1 and 2 are interconvertible under suitable conditions. 相似文献
80.
The purpose of this study is to analyze items that exhibit gender‐related Differential Item Functioning (DIF) in Mathematics in Jordan. Data was taken from the TIMSS 1999 of Jordan, which includes responses of 5,299 eighth grade students. Mantel‐Haenszel (MH) DIF procedure was applied to 124 multiple‐choice items. The results showed that 37 items exhibited gender‐related DIF. The analysis of the content of these items reflected some patterns that need further investigation. All the DIF items in measurement content favored male students while most of the DIF items in algebraic and data analysis contents favored female students. Most of the DIF items that negatively impacted on females were unfamiliar items that required some risk taking such as estimation, expectation, or approximation. On the other hand, most of the DIF items that favored females were familiar items which have one specific correct answer. Some implications for both research and teaching practice are provided. 相似文献