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271.
Serkan Demir Zuhal Yolcu Ömer Andaç Orhan Büyükgüngör Turan K. Yazıcılar 《Journal of molecular modeling》2010,16(9):1509-1518
A dinuclear centrosymmetric copper(II) complex with the formula [Cu2(μ-maa)4(maaH)2] has been synthesized and experimentally characterized by IR, electronic spectroscopy, and X-ray single-crystal diffractometry.
Starting from experimental X-ray geometry and using antiferromagnetic singlet ground state, gas phase geometry optimization
was performed by density functional hybrid (B3LYP) method with 6-31G(d) and LANL2DZ basis sets. Gas-phase vibrational frequencies
and single point energy (SPE) calculations have been carried out at the geometry-optimized structure. Molecular electrostatic
potential calculated at the optimized geometry and natural bond orbital analysis data have been extracted from SPE output.
The gas-phase electronic transitions of the title complex were investigated by the time dependent-density functional theory
(TD-DFT) approach with the same theory employing LANL2DZ basis set. Also the calculated UV-Vis based upon TD-DFT results and
IR spectra were simulated for comparison with the experimental ones. 相似文献
272.
Bulent Yalcin Hakan Akbulut Abdullah Buyukcelik Orhan Sencan Ahmet Demirkazik Handan Onur Filiz Cay Senler Dilek Dincol Fikri Icli 《Biological Rhythm Research》2004,35(4):259-268
This study was designed to assess the tolerability of chronomodulated infusion chemotherapy, individualized by the rhythm of peripheral blood cells. Twenty patients with metastatic gastric cancer were randomized to chronotherapy or day-time arms of 5-fluorouracil (FU) (600 mg/m2, 8 h inf.d1-5) and folinic acid (FA) (20 mg/m2, iv, d1-5) in the first cycle and crossed-over to the other arm in the following cycles. Ten of 18 evaluable patients were assigned to chronotherapy arm and eight to day-time in the first cycle. Although there was no significant difference between two arms on enrollment, chronotherapy arm yielded an improvement of 45% of QLQ-C30 scores (p = 0.021) and the day-time arm had 11% improvement (p = 0.575). After the crossing-over, chronotherapy arm, again, had a significant improvement in QLQ-C30 scores, compared to the day-time arm (14% vs. -18%, p = 0.001, respectively). Mucositis/diarrhea was significantly higher in the day-time arm compared to chronotherapy arm (p = 0.015). In conclusion, chronomodulated infusion of 5-FU might improve the quality of life. 相似文献
273.
International Microbiology - Ectoine and hydroxyectoine are compatible solutes with enormous potential for use in the medical and cosmetic industries. Considering the excellent osmoprotective... 相似文献
274.
Experiments were undertaken to investigate the existence of inhibitory nonadrenergic, noncholinergic (i-NANC) nerve activity by using in vitro functional and immunohistochemical techniques in rat main pulmonary arterial rings. Vessels precontracted with phenylephrine (3 microM) relaxed in response to electrical field stimulation (EFS) (50 V, 0.2 ms, 0.1-10 Hz for 5 s) in the presence of atropine (1 microM) and guanethidine (1 microM). Tetrodotoxin (0.3 microM) abolished this response, indicating that it is neuronal in origin. l-NAME (30 microM), methylene blue (10 microM), and removal of endothelium significantly reduced the EFS-induced relaxations. The inhibitory action of l-NAME was completely reversed by l-arginine (1 mM) but not by d-arginine (1 mM). Moreover l-arginine alone potentiated the magnitude of the relaxations elicited by EFS. On the other hand, immunohistochemical work clearly demonstrated the existence of neuronal nitric oxide synthase in the pulmonary artery vessel wall. All these results are consistent with the suggestion that nitric oxide is the likely mediator of this vasodilatation. However, the incomplete blockade of the responses by l-NAME gives evidence of an additional inhibitory NANC neurotransmitter(s) mediating the residual relaxation, which requires further experiments to clarify its nature. 相似文献
275.
Esengul Karahisar Osman Tugay Ilkay Erdogan Orhan Fatma Sezer Senol Deniz Simon Vlad Luca Krystyna Skalicka‐Wozniak Mustafa Sahin 《化学与生物多样性》2019,16(9)
In the current study, the ethanol extracts of flower, stem, and root parts of two endemic Turkish species, e. g., Haplophyllum sahinii O. Tugay & D. Uluku? and H. vulcanicum Boiss . & Heldr ., were screened against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) associated with Alzheimer's disease as well as tyrosinase (TYR) linked to Parkinson's disease using ELISA microplate assay at 200 μg/mL. Among the extracts, the highest inhibition was caused by the stem extract of H. sahinii against BChE (IC50=64.93±1.38 μg/mL). Consistently, all of the extracts were found to exert a selective inhibition towards BChE to some extent. It was only the root extract of H. vulcanicum that could inhibit AChE at low level (IC50=203.18±5.33 μg/mL). None of the extracts displayed an inhibition over 50 % against TYR. Metabolite profiling of the extracts was achieved by a highly hyphenated liquid chromatographic mass spectrometric technique (HPLC‐DAD‐ESI‐Q‐TOF‐MS/MS), which revealed the presence of furoquinoline (β‐fagarine, γ‐fagarine) and amide (tubasenicine, tubacetine) alkaloids; furano‐ (rutamarin), pyrano‐ (xanthyletine), and geranyloxy coumarins; phenylpropanoid (secoisolariciresinol), arylnaphthalene (mono‐O‐acetyldiphyllin apioside), and dibenzylbutyrolactone (kusunokinin, haplomyrfolin) lignans. Several important differences were observed between the extracts analyzed. β‐Fagarine was the major alkaloid in H. vulcanicum, whereas γ‐fagarine was present only in the roots of both Haplophyllum species; moreover, secoisolariciresinol and secoisolariciresinol dimethyl ether were the main lignans in the stems and flowers. This is the first study identifying ChE and TYR inhibitory effect and metabolic profiles of H. vulcanicum and H. sahinii. 相似文献
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277.
Mianzhi Wang Zhenling Zeng Fengwei Jiang Ying Zheng Huigang Shen Nubia Macedo Yongxue Sun Orhan Sahin Ganwu Li 《Environmental microbiology》2020,22(12):4974-4984
Enterotoxigenic Escherichia coli (ETEC) cause acute secretory diarrhoea in pigs, posing a great economic loss to the swine industry. This study analysed the prevalence and genetic characteristics of prophages from 132 ETEC isolates from symptomatic pigs to determine their potential for spreading antibiotic resistance. A total of 1105 potential prophages were identified, and the distribution of the genome size showed three ‘overlapping’ trends. Similarity matrix comparison showed that prophages correlated with the ETEC lineage distribution, and further identification of these prophages corroborated the lineage specificity. In total, 1206 antibiotic resistance genes (ARGs) of 52 different categories were identified in 132 ETEC strains; among these, 2.65% (32/1206) of ARGs were found to be carried by prophages. Analysis of flanking sequences showed that almost all the ARGs could be grouped into two types: ‘blaTEM-1B’ and ‘classic class 1 integron (IntI1)’. They co-occurred with a strictly conserved recombinase and transposon Tn3 family but with a difference: the ‘blaTEM-1B type’ prophages exhibited a classic Tn2 transposon structure with 100% sequence identity, whereas the ‘IntI1 type’ co-occurred with the TnAs2 transposon with only 84% sequence identity. These results imply that ARGs might be pervasive in natural bacterial populations through transmission by transposable bacteriophages. 相似文献
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279.
Mustafa Calapoğlu Orhan Değer Fulya Balaban Nilufer Şahin Calapoğlu Yılmaz Bülbül Keith Burling 《Biochemical genetics》2009,47(1-2):33-41
Deficiency of alpha-1-antitrypsin (α1-AT, a major protease inhibitor controlling tissue degradation) is a genetic disorder transmitted in a codominant autosomal form. It has more than 100 genetically determined variants. This study attempted to determine the degree of association between serum α1-AT levels and phenotypes and to provide a strategy for reliable laboratory evaluation of deficiencies. The study group consisted of a 38-year-old male proband with clinical features of emphysema, his first-degree relatives, and healthy controls. Family history revealed a four-generation pedigree. Genomic DNA was isolated from peripheral blood leukocytes. Alpha-1-AT levels were determined from human serum by immunonephelometry. Phenotypes were determined by isoelectric focusing of blood samples. DNA sequences of coding exons were analyzed by the amplification DNA technique and direct sequencing. Inheritance and plasma levels of the ZZ, MM, M3S, and MZ phenotypes were confirmed by the family study. In the family members with deficiencies, plasma concentrations were 22.55% ± 5.15 (ZZ), 84.18% ± 5.18 (M3S), and 61.06% ± 7.15 (MZ) of the normal MM level. We found a close association between α1-AT level and genotype. A combination of genotyping, quantification, and phenotyping is the optimal strategy for the laboratory evaluation of α1-AT deficiency. 相似文献
280.
Phytochemistry Reviews - 相似文献