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71.
The viability and a number of morphological properties of in situ astrocytes of rat spinal cord cultures including changes in surface area and migration of both cell body and nucleus were investigated at magnetic field intensities comparable to those currently used for magnetic resonance imaging. Viability of rat spinal astrocytes was studied after up to 72 hours of 2.1T static magnetic field exposure. Surface areas and two-dimensional centroids of both soma and nucleus after 2 hours of magnetic field exposure were determined and compared with those of the same cells before magnetic field exposure. Cell membrane ruffling was quantified using fractal analysis. 相似文献
72.
Hamid Reza Shaterian Hassan Hadadzadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1059-1071
A novel and simple method for the chemoselective deprotection of S,S- and S,O-acetals and ketals in the presence of their O,O-analogs with electrophilic halogens to their corresponding carbonyl compounds is described using N-bromosuccinimide, N-chlorosuccinimide, 2,4,4,6-tetrabromo-2,5-cyclohexen-1-one, trichlorocyanuric acid, or molecular bromine in aqueous acetonitrile. The use of these reagents in the presence of hydrated silica gel provide efficient, novel, and mild procedures for the deprotection of cyclic and acyclic O,O-, S,S-, and S,O-acetals and ketals in excellent yields in short reaction times. 相似文献
73.
Hamid Reza Shaterian Asghar Hosseinian Majid Ghashang 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):3136-3144
Herein, we describe a green procedure for the one-pot preparation of 1,8-dioxo-octahydroxanthene derivatives by condensation of dimedone and substituted benzaldehydes in the presence of FeCl 3 -SiO 2 as an efficient and heterogeneous catalyst under microwave irradiation and thermal conditions. This method has the advantages of high yields, cleaner reactions, efficient and cost-effective method, simple methodology, short reaction times, easy workup, and greener conditions. 相似文献
74.
Mustafa Aghazadeh Abbas-Ali Malek Barmi Hamid Mohammad Shiri 《Russian Journal of Electrochemistry》2013,49(4):344-353
Nanoparticles, nanospheres and nanorods of Y(OH)3 and Y2O3 were prepared via cathodic electrodeposition from chloride bath through applying different current densities. First, yttrium hydroxide precursors were cathodically grown on the cathode surface at the current densities of 2, 1, 0.5, 0.25 and 0.1 mA cm?2. Then hydroxide powders were heat-treated at 600°C for 3 h. The composition, crystal structure and morphology of the prepared oxide and hydroxide products were investigated by means of differential scanning calorimetery (DSC), X-ray diffraction (XRD), scanning and transmission electron microscopes (SEM and TEM) and FT-IR spectroscopy. Mechanism of base electrogeneration at the applied conditions, and intercalation of chloride ions in the deposit structure during the electrodeposition were proposed and confirmed by the XRD and TG analyses. The results showed that the structural and morphological properties of the products are directly dictated by the applied current density and it can be recognized as the main factor affecting on the cathodic electrodeposition of Y2O3. 相似文献
75.
76.
Hamid?Mofakham Rahim?Ghadari Ahmad?ShaabaniEmail author Milad?Pedarpour Sabrieh?Ghasemi 《Journal of the Iranian Chemical Society》2013,10(2):307-317
In this work, functionalized pyrimidine-2,4-dione-, benzo[g]-, and dihydropyrano[2,3-g]chromene derivatives have been synthesized via a Michael addition of 2-hydroxy-1,4-naphthoquinone or 2,5-dihydroxy-1,4-benzoquinone to the Knoevenagel condensation product of an aldehyde with Meldrum’s acid, dimedone or barbituric acid in the presence of a catalytic amount of l-proline under refluxing conditions in water in good to excellent yields. 相似文献
77.
Hamid Hadi-Alijanvand Ali A. Moosavi-Movahedi Bahram Goliaei 《Journal of the Iranian Chemical Society》2013,10(5):907-914
Prolyl hydroxylase domain 2 containing protein (PHD2) is a central protein in regulation of cellular response to hypoxia. This protein controls the responses of cell to oxygen level via the regulation of hypoxia inducible factor (HIF) stability. HIF induces the expression of many genes, especially ones orchestrate angiogenesis. There are some reports that mentioned in some tumor types the level of HIF is high in spite of the presence of wild-type PHD2 and normoxic environment. Therefore, the possibility of PHD2 misfolding in some cancer cells arises. Studying such important protein unfolding pathway is insightful for possible therapeutic approaches. In this study, the unfolding pathway of PHD2 illustrates utilizing molecular dynamics simulation of protein thermal denaturation. Based on current study results, we represent the possible mechanisms of PHD2 unfolding in detail. The possible intermediates of PHD2 thermal unfolding are characterized, and the most venomous state of its unfolding pathway is introduced. 相似文献
78.
Saied Saeed Hosseiny Davarani Hamid Reza Moazami Ali Reza Keshtkar Mohammad Hossein Banitaba Saeed Nojavan 《Analytica chimica acta》2013
A novel method for the selective electromembrane extraction (EME) of U6+ prior to fluorometric determination has been proposed. The effect of extraction conditions including supported liquid membrane (SLM) composition, extraction time and extraction voltage were investigated. An SLM composition of 1% di-2-ethyl hexyl phosphonic acid in nitrophenyl octyl ether (NPOE) showed good selectivity, recovery and enrichment factor. The best performance was achieved at an extraction potential of 80 volts and an extraction time of 14 minutes Under the optimized conditions, a linear range from 1 to 1000 ng mL−1 and LOD of 0.1 ng mL−1 were obtained for the determination of U6+. The EME method showed good performance in sample cleanup and the reduction of the interfering effects of Mn2+, Zn2+, Cd2+, Ni2+, Fe3+, Co2+, Cu2+, Cl− and PO43− ions during fluorometric determination of uranium in real water samples. The recoveries above 54% and enrichment factors above 64.7 were obtained by the proposed method for real sample analysis. 相似文献
79.
Carbon‐based solid acid was used as a new catalyst for conversion of trimethylsilyl ethers to their corresponding ethers in heterogeneous mixtures. The experiments were done moderately at room temperature, and high yields in suitable times were obtained under these conditions. 相似文献
80.
Mohammad Ali Zolfigol Maryam Kiany-borazjani Majid M. Sadeghi Hamid Reza Memarian Iraj Mohammadpoor-baltork 《合成通讯》2013,43(16):2945-2950
A combination of NaHSO4.H2O and NaNO2 in the presence of wet SiO2 was used as an effective oxidizing agent for the oxidation of dihydropyridines to their corresponding pyridine derivatives at room temperature with excellent yields. 相似文献