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排序方式: 共有116条查询结果,搜索用时 31 毫秒
1.
In this study, Fe3O4@TiO2 nanoparticles were synthesized as a new Positron Emission Tomography/Magnetic Resonance Imaging (PET/MRI) hybrid imaging agent and radiolabeled with 89Zr. In addition, Fe3O4 nanoparticles were synthesized and radiolabeled with 89Zr. Df-Bz-NCS was used as bifunctional ligand. The nanoconjugates were characterized with transmission electron microscopy, scanning electron microscopy, and dynamic light scattering. Radiolabeling yields were 100%. Breast and prostate cancer cell affinities and cytotoxicity were determined using in vitro cell culture assays. The results demonstrated that Fe3O4@TiO2 nanoparticles are promising for PET/MR imaging. Finally, unlike Fe3O4 nanoparticles, Fe3O4@TiO2 nanoparticles showed a fluorescence spectrum at an excitation wavelength of 250 nm and an emission wavelength of 314 nm. Therefore, in addition to bearing the magnetic properties of Fe3O4 nanoparticles, Fe3O4@TiO2 nanoparticles display fluorescence emission. This provides them with photodynamic therapy potential. Therefore multimodal treatment was performed with the combination of PDT and RT by using human prostate cancer cell line (PC3). The development of 89Zr-Df-Bz-NCS-Fe3O4@TiO2 nanoparticles as a new multifunctional PET/MRI agent with photodynamic therapy and hyperthermia therapeutic ability would be very useful. 相似文献
2.
Ibrahim Ari Vural Aksakalli Volkan Aydogˇdu Serdar Kum 《European Journal of Operational Research》2013
We consider the optimal ship navigation problem wherein the goal is to find the shortest path between two given coordinates in the presence of obstacles subject to safety distance and turn-radius constraints. These obstacles can be debris, rock formations, small islands, ice blocks, other ships, or even an entire coastline. We present a graph-theoretic solution on an appropriately-weighted directed graph representation of the navigation area obtained via 8-adjacency integer lattice discretization and utilization of the A∗ algorithm. We explicitly account for the following three conditions as part of the turn-radius constraints: (1) the ship’s left and right turn radii are different, (2) ship’s speed reduces while turning, and (3) the ship needs to navigate a certain minimum number of lattice edges along a straight line before making any turns. The last constraint ensures that the navigation area can be discretized at any desired resolution. Once the optimal (discrete) path is determined, we smoothen it to emulate the actual navigation of the ship. We illustrate our methodology on an ice navigation example involving a 100,000 DWT merchant ship and present a proof-of-concept by simulating the ship’s path in a full-mission ship handling simulator. 相似文献
3.
Avcıbaşı Uğur Türkyarar Taner Karadağ Ayşegül Bakan Buket Yavaşoğlu Nefise Ülkü Karabay Kuşat Kevser Akgöl Sinan Gülcemal Derya Tekin Volkan Müftüler Fazilet Zümrüt Biber Topal Gökcen Parlak Yasemin Gümüşer Fikriye Gül 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(2):511-525
Journal of Radioanalytical and Nuclear Chemistry - The aim of this study is the synthesis of a novel 99mTc-labeld graft polymer and the biological evaluation of its in vitro and in vivo properties.... 相似文献
4.
In this study, the semi-empirical and empirical calculations of K X-ray intensity ratios, K-shell fluorescence yields, and vacancy transfer probabilities have been performed for 3d transition elements. Also, σKα, σKβ production cross-sections, Kβ/Kα intensity ratios, ωK fluorescence yields, and ηKL vacancy transfer probabilities of 3d transition elements have been measured. The samples were excited by 59.5 keV γ-rays from a 241Am annular radioactive source. K X-rays emitted by samples were counted by an Ultra-LEGe detector with a resolution of 150 eV at 5.9 keV. 相似文献
5.
6.
Volkan Çakır Dilek Çakır Zekeriya Bıyıklıoğlu Halit Kantekin 《Journal of inclusion phenomena and macrocyclic chemistry》2014,78(1-4):61-70
In this study, a new phthalonitrile derivative 3 bearing 1,3-bis[3(dimethylamino)phenoxy]propan-2-ol 1, metal-free phthalocyanine (Pc) 4, metallophthalocyanines (MPcs) 5–7 and their quaternized derivatives 4a–7a were synthesized. Metal-free Pc 4 was prepared by cyclotetramerization of phthalonitrile derivate 3 and MPcs 5–7 were synthesized by heating 3 with NiCl2, CoCl2 and CuCl2 in n-pentanol in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene, respectively. Quaternization of the dimethylamino functionality produced quaternized octacationic water soluble metal-free, Ni, Co and Cu Pcs which were soluble in water, DMF, DMSO. The aggregation behaviour of these compounds were investigated in different concentrations of chloroform for metal-free, Ni, Co and Cu Pcs. The effect of solvents on absorption spectra were studied in various organic solvents. The novel compounds were characterized using IR, 1H-, 13C NMR, UV–vis and MS spectral data. 相似文献
7.
Kubra Kahremanoglu Ezgi Rana Temel Tamara Ecem Korkut Atakan Arda Nalbant Bersu Batu Azer Caner Durucan Murvet Volkan Ezel Boyaci 《Journal of separation science》2020,43(9-10):1925-1933
Recently the connection between oxidative stress and various diseases, including cancer and Alzheimer's, attracts notice as a pathway suitable for diagnostic purposes. 8‐Oxo‐deoxyguanosine and 8‐oxo‐deoxyadenosine produced from the interaction of reactive oxygen species with DNA become prominent as biomarkers. Several methods have been developed for their determination in biofluids, including solid‐phase extraction and enzyme‐linked immunosorbent assays. However, still, there is a need for reliable and fast analytical methods. In this context, solid‐phase microextraction offers many advantages such as flexibility in geometry and applicable sample volume, as well as high adaptability to high‐throughput sampling. In this study, a solid‐phase microextraction method was developed for the determination of 8‐oxo‐deoxyguanosine and 8‐oxo‐deoxyadenosine in biofluids. The extractive phase of solid‐phase microextraction consisted of hydrophilic–lipophilic balanced polymeric particles. In order to develop a solid‐phase microextraction method suitable for the determination of the analytes in saliva and urine, several parameters, including desorption solvent, desorption time, sample pH, and ionic strength, were scrutinized. Analytical figures of merit indicated that the developed method provides reasonable interday and intraday precisions (<15% in both biofluids) with acceptable accuracy. The method provides a limit of quantification for both biomarkers at 5.0 and 10.0 ng/mL levels in saliva and urine matrices, respectively. 相似文献
8.
K. Volkan
zdokur 《Electroanalysis》2020,32(3):489-495
Copper oxide decorated multi‐walled carbon nanotube (MWCNT) modified glassy carbon electrode (GCE) was prepared for determination of isoniazid (INZ) in various matrices. The electrochemical behavior of INZ was tested with the aid of Cyclic Voltammetry (CV) and quantitative experiments were performed by using Linear Sweep Voltammetry (LSV). Morphological and structural characterization of the modified electrode was performed by utilizing Scanning Electron Microscopy (SEM), X‐Ray Photoelectron Spectroscopy (XPS) while electrochemical characterization was performed by using CV and Electrochemical Impedance spectroscopy (EIS). The proposed sensor exhibited well defined anodic peak at 0.30 V for INZ at pH 6.0 medium. Under the optimum conditions, a linear relation between INZ concentration and peak current was observed in the range of 2.0×10?7 to 5.0×10?5 M. Limit of detection was calculated as 1.0×10?8 M and repeatability and accuracy was found as 5.60 % and 91.0 % for 5.0 10?7 M INZ by using 3 successive measurement, respectively. Then, the analytic performance of the electrode developed was tested by analyzing commercial tablets, artificial human serum and urine samples. The results indicated that satisfactory recoveries was observed for all issue. 相似文献
9.
Nuray Kup Aylikci 《光谱学快报》2013,46(6):346-355
AbstractIn this study, Kα1,2, Kβ1,3, and Kβ2,4 X-ray natural line widths for various elements were determined semi-empirically at 123.6?keV by using K shell fluorescence yields obtained from energy dispersive X-ray fluorescence measurements. The obtained results contribute to a database for the development of new theoretical models of atomic structure, radiation shielding materials, and designing new technological devices related to the structural analysis of materials. The obtained results were compared with the literature, while new fitting polynomials for the studied parameters were acquired. The results showed that the natural linewidths of K X-ray lines fit fourth-order polynomials except for Kβ2,4. 相似文献
10.
A novel synthetic method is introduced to prepare the biologically important montagnetol and erythrin compounds starting from a 1,3-benzodioxin-4-one, synthesized from commercially available orsellinic acid and erythritol. 相似文献