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141.
Aleksandra Krstic Aleksandar Pavic Edina Avdovic Zoran Markovic Milena Stevanovic Isidora Petrovic 《Molecules (Basel, Switzerland)》2022,27(7)
Pancreatic carcinoma still represents one of the most lethal malignant diseases in the world although some progress has been made in treating the disease in the past decades. Current multi-agent treatment options have improved the overall survival of patients, however, more effective treatment strategies are still needed. In this paper we have characterized the anticancer potential of coumarin-palladium(II) complex against pancreatic carcinoma cells. Cells viability, colony formation and migratory potential of pancreatic carcinoma cells were assessed in vitro, followed by evaluation of apoptosis induction and in vivo testing on zebrafish. Presented results showed remarkable reduction in pancreatic carcinoma cells growth both in vitro and in vivo, being effective at micromolar concentrations (0.5 μM). Treatments induced apoptosis, increased BAX/BCL-2 ratio and suppressed the expression of SOX9 and SOX18, genes shown to be significantly up-regulated in pancreatic ductal adenocarcinoma. Importantly, treatments of the zebrafish-pancreatic adenocarcinoma xenografts resulted in significant reduction in tumor mass, without provoking any adverse toxic effects including hepatotoxicity. Presented results indicate the great potential of the tested compound and the perspective of its further development towards pancreatic cancer therapy. 相似文献
142.
Katica Serti-Bionda Zoran Gomzi Maja Fabuli-Ruszkowski 《Reaction Kinetics and Catalysis Letters》2006,88(1):111-118
Summary In the present work catalytic cracking of gas oils has been studied in a standard MAT reactor. The cracking product distribution
was measured at four different temperatures. Based on the experimental results, a 4-lump kinetic model was applied. Kinetic
constants were estimated using the sequential step optimization method. Simulation results have shown to be in a good agreement
with experimental data. An isothermal pseudo steady-state model for fixed bed MAT reactor is proposed. 相似文献
143.
Zoran Markovi 《Mathematical Logic Quarterly》1993,39(1):531-538
Since in Heyting Arithmetic (HA) all atomic formulas are decidable, a Kripke model for HA may be regarded classically as a collection of classical structures for the language of arithmetic, partially ordered by the submodel relation. The obvious question is then: are these classical structures models of Peano Arithmetic (PA)? And dually: if a collection of models of PA, partially ordered by the submodel relation, is regarded as a Kripke model, is it a model of HA? Some partial answers to these questions were obtained in [6], [3], [1] and [2]. Here we present some results in the same direction, announced in [7]. In particular, it is proved that the classical structures at the nodes of a Kripke model of HA must be models of IΔ1 (PA- with induction for provably Δ1 formulas) and that the relation between these classical structures must be that of a Δ1-elementary submodel. MSC: 03F30, 03F55. 相似文献
144.
Assembly and charge transfer in hybrid TiO(2) architectures using biotin-avidin as a connector 总被引:1,自引:0,他引:1
Dimitrijevic NM Saponjic ZV Rabatic BM Rajh T 《Journal of the American Chemical Society》2005,127(5):1344-1345
Exploiting the presence of undercoordinated surface Ti atoms at the tips of TiO2 nanorods and the dopamine selectivity for these Ti surface states, biotin was conjugated to TiO2 nanocrystallites using dopamine as a bridging linker. Using abiotin-avidin complex as a connector the "tip-to-tip" assembly of 400 nm elongated TiO2 rods was obtained. The photoexcitation of avidin-TiO2 hybrids resulted in the transfer of holes from nanocrystallites to protein and consequent oxidation of avidin, most probably at tyrosine 33. 相似文献
145.
Strancar J Koklic T Arsov Z Filipic B Stopar D Hemminga MA 《Journal of chemical information and modeling》2005,45(2):394-406
Following the widely spread EPR spin-label applications for biosystem characterization, a novel approach is proposed for EPR-based characterization of biosystem complexity. Hereto a computational method based on a hybrid evolutionary optimization (HEO) is introduced. The enormous volume of information obtained from multiple HEO runs is reduced with a novel so-called GHOST condensation method for automatic detection of the degree of system complexity through the construction of two-dimensional solution distributions. The GHOST method shows the ability of automatic quantitative characterization of groups of solutions, e.g. the determination of average spectral parameters and group contributions. The application of the GHOST condensation algorithm is demonstrated on four synthetic examples of different complexity and applied to two physiologically relevant examples--the determination of domains in biomembranes (lateral heterogeneity) and the study of the low-resolution structure of membrane proteins. 相似文献
146.
147.
148.
Zoran Samardzžija Slavko Bernik Ryna B. Marinenko Barbara Malič Miran Čeh 《Mikrochimica acta》2004,145(1-4):203-208
Single crystals of KNbO3 and NaNbO3 were selected from the limited number of suitable alkali compounds that are available and evaluated as possible reference materials for the electron-probe microanalysis (EPMA) of alkaline niobates with a composition described by the general formula K1–XNaXNbO3. The EPMA study verified that KNbO3 and NaNbO3 single crystals are stable under the electron beam and compositionally homogeneous. A quantitative microanalysis confirmed the composition of pure KNbO3, while the NaNbO3 crystal contained 0.3 mass fraction % of Ca. A significant improvement in the accuracy of the quantitative EPMA of polycrystalline potassium–sodium niobates was achieved using these single crystals as standards. The crystals can also be useful as reference materials for the analysis of sodium and potassium in other materials. 相似文献
149.
Konstantin Mohr Zoran Andelkovic Aineah Wekesa Barasa Axel Buß Volker Hannen Wilfried Nörtershäuser Tim Ratajczyk Rodolfo Sánchez 《X射线光谱测定》2020,49(1):169-172
CRYRING@ESR is a newly installed low energy ring integrated in the GSI accelerator facility. In this paper we describe developments of the laser spectroscopy experiment at CRYRING@ESR. In the past commissioning beam time in November, the recently installed data acquisition system was tested. Light emitted by excited residual gas atoms was detected by a single-photon tagging technique. The time dependence of the ion beam intensity was investigated with this tool. 相似文献
150.
Zoran Andelkovic Gerhard Birkl Svetlana Fedotova Volker Hannen Frank Herfurth Kristian König Nikita Kotovskiy Bernhard Maaß Jonas Vollbrecht Tobias Murböck Dennis Neidherr Wilfried Nörtershäuser Stefan Schmidt Manuel Vogel Gleb Vorobjev Christian Weinheimer 《Hyperfine Interactions》2015,231(1-3):37-44
Heavy few-electron ions are relatively simple systems in terms of electron structure and offer unique opportunities to conduct experiments under extremely large electromagnetic fields that exist around their nuclei. However, the preparation of highly charged ions (HCI) has remained the major challenge for experiments. As an extension of the existing GSI accelerator facility, the HITRAP facility was conceived as a multi-stage decelerator for HCI produced at high velocity. It is designed to prepare bunches of around 105 HCI and to deliver them at low energies to various experiments. One of these experiments is SpecTrap, aiming for laser spectroscopy of trapped, cold HCI. We present the latest results on deceleration of ions in a radio-frequency quadrupole, synchrotron cooling of electrons in a trap as a preparation step for the prospective electron cooling of the HCI decelerated in HITRAP, as well as laser cooling of singly charged Mg ions for sympathetic cooling of HCI in SpecTrap. 相似文献