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101.
Sanaa Eissa Hassan M. E. Azzazy Marwa Matboli Sherif M. Shawky Hebatallah Said Fatin A. Anous 《Applied biochemistry and biotechnology》2014,174(2):751-761
The aim of is this study is to explore the role of tissue histidine-rich glycoprotein (HRG) RNA as a promising clinically useful biomarker for breast cancer patients prognosis using nanogold assay. Expression of the HRG RNA was assessed by gold nanoparticles and conventional RT-PCR after purification by magnetic nanoparticles in breast tissue samples. The study included 120 patients, 60 of which were histologically proven breast carcinoma cases, 30 had benign breast lesions and 30 were healthy individuals who had undergone reductive plastic surgery. ER, PR and HER2 status were also investigated. The prognostic significance of tissue HRG RNA expression in breast cancer was explored. The magnetic nanoparticles coated with specific thiol modified oligonucleotide probe were used successfully in purification of HRG RNA from breast tissue total RNAs with satisfactory yield. The developed HRG AuNPs assay had a sensitivity and a specificity of 90 %, and a detection limit of 1.5 nmol/l. The concordance rate between the HRG AuNPs assay with RT-PCR after RNA purification using magnetic nanoparticles was 93.3 %. The median follow-up period was 60 months. Among traditional prognostic biomarkers, HRG was a significant independent prognostic marker in relapse-free survival (RFS). HRG RNA is an independent prognostic marker for breast cancer and can be detected using gold NPs assay, which is rapid, sensitive, specific, inexpensive to extend the value for breast cancer prognosis. 相似文献
102.
Electrodeposition and Magnetic Characterization of Iron and Iron–Silicon Alloys from the Ionic Liquid 1‐Butyl‐1‐methylpyrrolidinium Trifluoromethylsulfonate
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Dr. Pulletikurthi Giridhar Dr. Bernd Weidenfeller Dr. Sherif Zein El Abedin Prof. Dr. Frank Endres 《Chemphyschem》2014,15(16):3515-3522
The electrodeposition of soft magnetic iron and iron–silicon alloys for magnetic measurements is presented. The preparation of these materials in 1‐butyl‐1‐methylpyrrolidinium trifluoromethylsulfonate, [Py1,4]TfO, at 100 °C with FeCl2 and FeCl2+SiCl4 was studied by using cyclic voltammetry. Constant‐potential electrolysis was carried out to deposit either Fe or FeSi, and deposits of approximately 10 μm thicknesses were obtained. By using scanning electron microscopy and X‐ray diffraction, the microstructure and crystallinity of the deposits were investigated. Grain sizes in the nanometer regime (50–80 nm) were found and the presence of iron–silicon alloys was verified. Frequency‐dependent magnetic polarizations, coercive forces, and power losses of some deposits were determined by using a digital hysteresis recorder. Corresponding to the small grain sizes, the coercive forces are around 950–1150 A m?1 and the power losses were at 6000 J m?3, which is much higher than in commercial Fe(3.2 wt %)Si electrical steel. Below a polarization of 1.8 T, the power losses are mainly caused by domain wall movements and, above 1.8 T, by rotation of magnetic moments as well as domain wall annihilation and recreation. 相似文献
103.
M. H. Sherif 《Research on Chemical Intermediates》2014,40(2):887-901
5-(P-tolyl)-2-[(3-bromo-4-methoxy benzylidene) hydrazino]-thiazole 3, 3-[(3-bromo-4-mehtoxy benzylidine) amino]-2-thiohydantion 5, and 4,6-disubstituted-3-[(3-bromo-4-methoxybenzyliden) amino]-2-thioxo pyrimidines 10 have been prepared via cyclization of 3-bromo-4-methoxy benzaldehyde thiosemicarbazone 2 with 4-methyl phenacyl bromide, ethyl chloroacetate, and dicarbonyl compounds in different conditions. Acetylation of 3 and 5 with acetic anhydride gave the corresponding monoacetyl derivatives 4 and 6, while the acetylation of 5 with acetic anhydride in the presence of fused sodium acetate gave diacetyl derivative 7. Condensation of compound 5 with benzaldehyde in the presence of piperidine yielded the corresponding 3-substituted-5-benzylindene 2-thiohydation 8. Acetylation of compound 8 with acetic anhydride gave the corresponding 1-acetyl-3-substituted-5-benzylidene-2-thiohydantion 9. The mass spectral fragmentation patterns of some prepared compounds are investigated in order to elucidate the structure of the synthesized nitrogen heterocycles. 相似文献
104.
105.
C. Mitros Sherif Yehia Sanjeev Kumar S. Jha M. DeMarco Dale Mitchell Glenn M. Julian R. A. Dunlap 《Hyperfine Interactions》1987,34(1-4):419-422
Hmf values are reported for Fe-57 in Ni2MnGa, and for Cd-111, Fe-57, and Sn-119 in Pd2MnSn and Ru2FeSn. 相似文献
106.
This article discusses a chemical route to prepare new ethylene/propylene copolymers (EP) containing a terminal reactive group, such as ?‐CH3 and OH. The chemistry involves metallocene‐mediated ethylene/propylene copolymerization in the presence of a consecutive chain transfer agent—a mixture of hydrogen and styrene derivatives carrying a CH3 (p‐MS) or a silane‐protected OH (St‐OSi). The major challenge is to find suitable reaction conditions that can simultaneously carry out effective ethylene/propylene copolymerization and incorporation of the styrenic molecule (St‐f) at the polymer chain end, in other words, altering the St‐f incorporation mode from copolymerization to chain transfer. A systematic study was conducted to examine several metallocene catalyst systems and reaction conditions. Both [(C5Me4)SiMe2N(t‐Bu)]TiCl2 and rac‐Et(Ind)2ZrCl2, under certain H2 pressures, were found to be suitable catalyst systems to perform the combined task. A broad range of St‐f terminated EP copolymers (EP‐t‐p‐MS and EP‐t‐St‐OH), with various compositions and molecular weights, have been prepared with polymer molecular weight inversely proportional to the molar ratio of [St‐f]/[monomer]. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1858–1872, 2005 相似文献
107.
S. A. Sayed A. T. Kandil G. R. Choppin 《Journal of Radioanalytical and Nuclear Chemistry》1994,188(5):377-390
The stability constants of UO
2
2+
-squarate complexes are measured at ionic strengths of 0.05M, 0.06M, 0.075M, 0.09M, 0.1M (squaric acid-perchloric acid) using a solvent extraction method at a pH of 1.1 and a temperature of 25 °C. The extractant used is dinonylnaphthalenesulfonic acid in n-heptane. The aqueous phase was made of a mixture of squaric and perchloric acid and233U radio tracer. The stability constants of squarate complexes of UO
2
2+
is seen to decrease linearly with the square root of the ionic strength. 相似文献
108.
109.
Sherif Abdelmoez Rehab A. Abd El Azeem Ahmed A. Nada Tawfik A. Khattab 《无机化学与普通化学杂志》2016,642(3):219-221
Nowadays, encapsulated dyes in a polymeric matrix have opened up new perspectives in many applications such as filtration of subatomic particles, composite reinforcement, multifunctional membranes, tissue engineering scaffolds, wound dressing, coatings, medical purposes as well as sensors. In the presented work, we report on electrospinning neat peryelene dianhydride based thermoplastic elastomers. Perylene‐3, 4,9, 10‐tetracarboxylic dianhydride (PDA) is encapsulated into cellulose acetate (CA) electrospun fibers, which was prepared from 12 % cellulose acetate solution, at 20 kV with a distance of 10 cm. The flow rate was 0.2 ml · h–1. These water repellent nanofibrous coatings are anticipated to serve as hydrophobic coatings. Scanning electron microscope is used to study the properties of the electrospun PDA‐CA nanofibers. 相似文献
110.
Hamdoon A. Mohammed Mohsen S. Al-Omar Salman A. A. Mohammed Ahmad H. Alhowail Hussein M. Eldeeb Mohammed S. M. Sajid Essam M. Abd-Elmoniem Osama A. Alghulayqeh Yasser I. Kandil Riaz A. Khan 《Molecules (Basel, Switzerland)》2021,26(8)
Salsola cyclophylla, an edible halophyte, is traditionally used for inflammation and pain. To confirm the claimed anti-inflammatory and analgesic properties, a detailed study on respective pharmacological actions was undertaken. The activities are contemplated to arise from its phytoconstituents. The LC-MS analysis of S. cyclophylla 95% aqueous-ethanolic extract revealed the presence of 52 compounds belonging to phenols, flavonoids, coumarins, and aliphatics class. A high concentration of Mn, Fe, and Zn was detected by atomic absorption spectroscopic analysis. The ethyl acetate extract showed the highest flavonoid contents (5.94 ± 0.04 mg/g, Quercetin Equivalents) and Fe2+-chelation (52%) potential with DPPH radicals-quenching IC50 at 1.35 ± 0.16 mg/mL, while the aqueous ethanolic extract exhibited maximum phenolics contents (136.08 ± 0.12 mg/g, gallic acid equivalents) with DPPH scavenging potential at IC50 0.615 ± 0.06 mg/mL. Aqueous ethanolic extract and standard quercetin DPPH radicals scavenging’s were equal potent at 10 mg/mL concentrations. The aqueous ethanolic extract showed highest analgesic effect with pain reduction rates 89.86% (p = 0.03), 87.50% (p < 0.01), and 99.66% (p = 0.0004) after 60, 90, and 120 min, respectively. Additionally, aqueous ethanolic extract exhibited the highest anti-inflammation capacity at 41.07% (p < 0.0001), 34.51% (p < 0.0001), and 24.82% (p < 0.0001) after 2, 3, and 6 h of extract’s administration, respectively. The phytochemical constituents, significant anti-oxidant potential, remarkable analgesic, and anti-inflammatory bioactivities of extracts supported the traditionally claimed anti-inflammatory and analgesic plant activities. 相似文献