排序方式: 共有183条查询结果,搜索用时 15 毫秒
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Nurdan YAZICI BEKTA Ezgi ERSOY Mehmet BOA Tue BORAN Ercan INAR Gül
ZHAN Ahmet Ceyhan G
REN Esra EROLU
ZKAN 《Turkish Journal of Chemistry》2021,45(5):1621
The study aims to determine the secondary metabolites of Hypericum androsaemum L. extracts by liquid chromatography-high resolution mass spectrometry (LC-HRMS), and investigate the antioxidant and cytotoxic activities of the plant. Cytotoxic activity was evaluated by MTT assay, and apoptosis induction abilities on human prostate adenocarcinoma (PC-3), and hepatocellular carcinoma (Hep G2) cell lines. Accordingly, major secondary metabolites were found as hederagenin (762 ± 70.10 μg/g) in the leaves dichloromethane (LD), herniarin (167 ± 1.50 μg/g) in fruit dichloromethane (FD), (-)-epicatechin (6538 ± 235.36 μg/g) in the leaves methanol (LM), (-)-epigallocatechin gallate (758 ± 20.46 μg/g) in the fruit methanol (FM), and caffeic acid (370 ± 8.88 μg/g) in the fruit water (FW), and (3313 ± 79.51 μg/g) in the leaves water (LW) extracts. LM exerted strong antioxidant activity in DPPH free (IC50 10.94 ± 0.08 μg/mL), and ABTS cation radicals scavenging (IC50 9.09 ± 0.05 μg/mL) activities. FM exhibited cytotoxic activity with IC50 values of 73.23 ± 3.06 µg/mL and 31.64 ± 2.75 µg/mL on PC-3 and Hep G2 cell lines, respectively. Being the richest extract in terms of quillaic acid (630 ± 18.9 μg/g), which is a well-known cytotoxic triterpenoid with proven apoptosis induction ability on different cells, FM extract showed apoptosis induction activity with 64.75% on PC-3 cells at 50 μg/mL concentration. The study provides promising results about the potential of Hypericum androsaemum on cancer prevention. 相似文献
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Ahmet Atilgan Esra TanriverdiEik Ruslan Guliyev T. Bilal Uyar Sundus Erbas‐Cakmak Engin U. Akkaya 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(40):10854-10857
A ligand incorporating a dithioethenyl moiety is cleaved into fragments which have a lower metal‐ion affinity upon irradiation with low‐energy red/near‐IR light. The cleavage is a result of singlet oxygen generation which occurs on excitation of the photosensitizer modules. The method has many tunable factors that could make it a satisfactory caging strategy for metal ions. 相似文献
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Bilgin Simsek Esra Novak Ivan Sausa Ondrej Berek Dusan 《Research on Chemical Intermediates》2017,43(1):503-522
Research on Chemical Intermediates - Cellulose-based microporous carbon fibers (CFs) were evaluated for the adsorption of 2-Chlorophenol (CP), 2,4-Dichlorophenol (DCP), and 2,4,6-Trichlorophenol... 相似文献
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From Dark to Light to Fluorescence Resonance Energy Transfer (FRET): Polarity‐Sensitive Aggregation‐Induced Emission (AIE)‐Active Tetraphenylethene‐Fused BODIPY Dyes with a Very Large Pseudo‐Stokes Shift
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Esra Şen Dr. Kadem Meral Dr. Serdar Atılgan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(2):736-745
The work presented herein is devoted to the fabrication of large Stokes shift dyes in both organic and aqueous media by combining dark resonance energy transfer (DRET) and fluorescence resonance energy transfer (FRET) in one donor–acceptor system. In this respect, a series of donor–acceptor architectures of 4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene (BODIPY) dyes substituted by one, two, or three tetraphenylethene (TPE) luminogens were designed and synthesised. The photophysical properties of these three chromophore systems were studied to provide insight into the nature of donor–acceptor interactions in both THF and aqueous media. Because the generation of emissive TPE donor(s) is strongly polarity dependent, due to its aggregation‐induced emission (AIE) feature, one might expect the formation of appreciable fluorescence emission intensity with a very large pseudo‐Stokes shift in aqueous media when considering FRET process. Interestingly, similar results were also recorded in THF for the chromophore systems, although the TPE fragment(s) of the dyes are non‐emissive. The explanation for this photophysical behaviour lies in the DRET. This is the first report on combining two energy‐transfer processes, namely, FRET and DRET, in one polarity‐sensitive donor–acceptor pair system. The accuracy of the dark‐emissive donor property of the TPE luminogen is also presented for the first time as a new feature for AIE phenomena. 相似文献
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Journal of Thermal Analysis and Calorimetry - The aluminate hosts were basically activated with the Eu3+- and Ho3+-ions which were prepared by solid-state reaction in this study. The DTA/TG results... 相似文献
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Simulation modeling for emergency bed requirement planning 总被引:1,自引:0,他引:1
Due to its highly stochastic nature and complex interaction between services involved, health care has been a demanding area of application for computer simulation. This paper includes details and results of a simulation study realized in the Surgical Emergency Department at Istanbul University School of Medicine. The purpose is to suggest new bed capacities to improve the current system, and also to provide the management with guidelines for their expansion plans. For this aim, arrival rates, treatment procedures, inpatient admittance, and service durations have been carefully analyzed and modeled. The model, coded in SLAM-II simulation language, has been run under several bed capacity scenarios, and resulting queueing and waiting patterns have been discussed in detail.Dedictated to Professor Nusret Fiek 相似文献
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Margaux Fresnais Esra Yildirim Seda Karabulut Dirk Jger Inka Zrnig Julia Benzel Kristian W. Pajtler Stefan M. Pfister Jürgen Burhenne Walter E. Haefeli Rmi Longuespe 《Molecules (Basel, Switzerland)》2021,26(5)
Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has rarely been used in the field of therapeutic drug monitoring, partly because of the complexity of the ionization processes between the compounds to be quantified and the many MALDI matrices available. The development of a viable MALDI-MS method that meets regulatory guidelines for bioanalytical method validation requires prior knowledge of the suitability of (i) the MALDI matrix with the analyte class and properties for ionization, (ii) the crystallization properties of the MALDI matrix with automation features, and (iii) the MS instrumentation used to achieve sensitive and specific measurements in order to determine low pharmacological drug concentrations in biological matrices. In the present hybrid article/white paper, we review the developments required for the establishment of MALDI-MS assays for the quantification of drugs in tissues and plasma, illustrated with concrete results for the different steps. We summarize the necessary parameters that need to be controlled for the successful development of fully validated MALDI-MS methods according to regulatory authorities, as well as currently unsolved problems and promising ways to address them. Finally, we propose an expert opinion on future perspectives and needs in order to establish MALDI-MS as a universal method for therapeutic drug monitoring. 相似文献