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51.
Neslihan Tekin Kamile Öztürk Talat Baran Barış Kerimoğlu Mehtap Tarhan Ayfer Menteş 《高分子科学杂志,A辑:纯化学与应用化学》2017,54(5):263-270
In the investigation for alternative chemotherapeutic strategies against leukemia, Pd(II) complexes were synthesized and investigated for cytotoxic and apoptotic properties on two human leukemia cell lines (HL-60 and K562). Pd(II) complexes (Pd-5a and Pd-6a) with 5a and 6a as ligands were synthesized and characterized by 1H-NMR and F-TIR. The cytotoxicity of the compounds was quantified using MTT method. Bax, Bcl-2, and caspase 3 gene expression levels were estimated using RT-qPCR. Here we show that Pd(II) complexes have important cytotoxic activity on human leukemia cell lines. RT-qPCR indicated that Bax and caspase 3 gene expression levels were increased after 24 h treatment with Pd-5a and Pd-6a complexes in both HL-60 and K562 cells at some selected dose. Furthermore, Bcl-2 gene expression level decreased after 24 h treatment with Pd-5a and Pd-6a complexes in K562 cells at all selected dose. In HL-60 cells, only one selected Pd-5a dose (25 µM) decreased the gene expression level of Bcl-2. The results obtained in the present investigation indicate that these two newly synthesized Pd(II) complexes have apoptotic effects at appropriate doses through caspase 3 and Bax genes and might represent a novel potentially active agents for the management of human leukemia cell lines. 相似文献
52.
Salman H. Abbas 《应用数学和力学(英文版)》1996,17(12):1141-1146
THE THEORETICAL COST OF SEQUENTIAL AND PARALLEL ALGORITHMS FOR SOLVING LINEAR SYSTEMS OF EQUATIONSSalmanH.Abbas(ReceivedMay24... 相似文献
53.
We study the convergence of the Pre?i? type k‐step iterative method for a class of operators satisfying Pre?i? type contractive conditions on the setting of partial metric spaces. Some examples are presented to illustrate our obtained results. As applications of the presented convergence theorems, we derive global attractivity results for a class of matrix difference equations. Numerical experiments are also presented to illustrate the theoretical findings. 相似文献
54.
Abraham Y Salman H Suwinska K Eichen Y 《Chemical communications (Cambridge, England)》2011,47(21):6087-6089
Cyclo[2]benzimidazole is a new host for anions that turns on its luminescence up to 150 fold upon binding. Photoexcited cyclo[2]benzimidazole undergoes an efficient non-radiative deactivation through an excited-state intramolecular proton-transfer (ESIPT) mechanism. Upon binding an anion, the ESIPT pathway is blocked, resulting in an increase in the luminescence efficiency. 相似文献
55.
Abstract The uv-vis spectra of eight ortho-hydroxy- andpara-hydroxy schiff bases were recorded in different solvents. Inductive and resonance effect of the substituents affect the electronic spectra of those molecules, while, intra-molecular hydrogen bond formation or breakage have little effect on the uv-visible spectra. 相似文献
56.
The UV spectra of some chlorinated o-hydroxyschiff bases were studied in different solvents. It was found that schiff bases derived from condensation of 2-hydroxybenzaldehyde or 5-chloro-2-hydroxy benzaldehyde with substituted aniline exist as enol form, whereas schiff bases derived from the condensation of 3,5-dichloro-2-hydroxybenzaldehyde with substituted aniline exist as enol form, whereas schiff bases derived from the condensation of 3,5-dichloro-2-hydroxybenzaldehyde with aniline exist as keto form especially in dimethyl sulfoxide. The ratio of enol/keto isomers were calculated for these schiff bases. 相似文献
57.
The carbon-13 chemical shift of seventeen N-substituted 2,4,6-triphenyl pyridinium salts (TPP) and N-substituted 2,4,6-triaryl pyridinium (TsPP) salts have been determined. 相似文献
58.
Summary We prove a Schur test for mixed-norm spaces Lp,q, 1 < p,q < ∞. Also we prove another version of the Schur test for discrete weighted mixed-norm spaces lp,q w, 1 < p,q < ∞, and wis a weight. We show that if w 1, and w 2are two weight functions on the index sets Jx Iand K x Lrespectively, and A =(a ji, kl ) j∈J, i∈I, k∈K, l∈L is an infinite matrix, then under certain conditions, Ais a bounded operator from lp,q w1, 1 < p,q < ∞ to lp,q w2. This will be a key result in proving boundedness of important operators in our work in time-frequency analysis.</o:p> 相似文献
59.
本文讨论了求解密集型线性方程组的两种并行算法。这两种算法都在下上单元(LU)分解。法的基础上使用了前向和后向置换进行的。这些算法在数值上是稳定的,并在顺序平衡机上用各种处理程序进行试验,都得到良好效果。 相似文献
60.
Salman R. Salman 《Magnetic resonance in chemistry : MRC》1984,22(6):385-387
Long-range proton–proton coupling constants between the hydroxy proton and ring protons were employed to deduce the conformational preferences of 1- and 2-hydroxynaphthalene. 2,6-Dibromo-1,5-dihydroxy-naphthalene, 2-acetyl-1-hydroxynaphthalene, 1,6-dibromo-2-hydroxynaphthalene and 2-hydroxy-1-naphthaldehyde were used as model compounds. Molecular orbital calculations at the CNDO/2 and INDO level were used to calculate the energy and the long-range proton–proton coupling of different conformers of 1- and 2-hydroxynaphthalene. 相似文献