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21.
Targeting tumor vasculature through specific endothelial cell markers represents a promising approach for cancer treatment. Here our aim was to construct an antibiotic resistance gene-free plasmid encoding shRNAs to simultaneously target two endothelial cell markers, CD105 and CD146, and to test its functionality and therapeutic potential in vitro when delivered by gene electrotransfer (GET) and combined with irradiation (IR). Functionality of the plasmid was evaluated by determining the silencing of the targeted genes using qRT-PCR. Antiproliferative and antiangiogenic effects were determined by the cytotoxicity assay tube formation assay and wound healing assay in murine endothelial cells 2H-11. The functionality of the plasmid construct was also evaluated in malignant melanoma tumor cell line B16F10. Additionally, potential activation of immune response was measured by induction of DNA sensor STING and proinflammatory cytokines by qRT-PCR in endothelial cells 2H-11. We demonstrated that the plasmid construction was successful and can efficiently silence the expression of the two targeted genes. As a consequence of silencing, reduced migration rate and angiogenic potential was confirmed in 2H-11 endothelial cells. Furthermore, induction of DNA sensor STING and proinflammatory cytokines were determined, which could add to the therapeutic effectiveness when used in vivo. To conclude, we successfully constructed a novel plasmid DNA with two shRNAs, which holds a great promise for further in vivo testing.  相似文献   
22.
The objective of this study is to perform a sensitivity analysis of the SHETRAN model on the example of the torrential Lukovska River catchment in Serbia. The sensitivity analysis of the model was performed for the following parameters: the vertical saturated hydraulic conductivity of the subsurface soil, the horizontal saturated hydraulic conductivity in the saturated zone, the Strickler roughness coefficients for overland flow and for streams, the available water content in the soil and the erodibility coefficients due to rain and due to overland flow. It can be concluded that the water and sediment discharge are very sensitive to the values of the vertical saturated hydraulic conductivity of the subsurface soil in the range of 0.001 to 0.1 m/day; to the values of the horizontal saturated hydraulic conductivity in the saturated zone in the range of 0.01 to 5 m/day and to the values of the Strickler’s coefficients for overland flow and for rivers in the range of 0.1 to 100 m1/3s-1 and 15 to 40 m1/3s, respectively. The sediment concentrations in a flow and sediment discharge are very sensitive to the values of erodibility coefficient due to overland flow in the range of 0.5 to 1.5 mg/m2s and to the values of erodibility coefficient due to rain in the range between 0.1 and 40 J-1. The obtained results could be used to simplify the parameter calibration procedure and to facilitate estimation of parameters in ungauged mountainous basins of similar characteristics.  相似文献   
23.
This paper describes the use of the dual isotope method involving δ(15)N and δ(18)O measurements of dissolved nitrates to assess the origin and fate of groundwater nitrate at the Klju? groundwater source, Serbia. A sampling campaign was conducted in September 2007 during flow conditions obtaining groundwater from observation wells and river water fed by a shallow aquifer hosted in alluvial (sandy-gravel) sediments. Nitrate isotope ratios ranged from +5.3 to +16.9‰ and δ(18)O(NO(3)) values varied from -2.3 to +5.0‰. Two major contamination sources were identified with isotopic compositions characteristic for nitrate derived from nitrification of soil organic nitrogen (+5.3 to +7.8‰ for δ(15)N) resulting in nitrate concentrations of 33.6 and 78.8 mg/L and nitrate derived from animal wastes or human sewage, e.g. via septic systems, yielding δ(15)N values of +9.9 to +11.9‰ and elevated nitrate concentrations of 31.2-245.8 mg/L. The occurrence of nitrification and denitrification was also revealed based on concentration and isotope data for dissolved nitrate.  相似文献   
24.
Potential beneficial components, including proteins, total phenolics, total flavonoids, carotenoids, tocopherols, and DPPH radical scavenging activity, were investigated in wholemeal of ten bread (T. aestivum L.) and ten durum (T. durum Desf.) novel wheat genotypes. In addition, the activity rate of lipoxygenase (LOX) and peroxidase (POD) enzymes implicated in the antioxidant metabolism was determined. The protein contnet and the antioxidant properties varied according to the two different wheat species, as well as, between the different bread and durum wheat genotypes themselves. The results indicated significant differences in proteins and antioxidant compounds between bread and durum wheat. Higher total proteins, wet gluten and antioxidants contents, combined with lower LOX and POD activities, point to a higher nutritive value of durum wheat than bread wheat.  相似文献   
25.
More difficult conditions of oil production process in recent years impose the necessity of finding out new technical solutions that will provide reliable and efficient lifting of reservoir fluid to the surface.Technical solution presented in this paper, hydraulically driven piston pump, is one of the attempts in the field of artificial exploitation methods, to find a solution that will work effectively in different well types (vertical, horizontal and directional) and at depths that are greater than those achieved until today.The task of this paper is to show the innovation in the pump construction. Innovations are made in the coiled tubing construction, one pipeline instead two or three; double acting type pump with reservoir fluid repression, towards the surface, through a channel drilled in the piston.The new technical solution, laboratory prototype, has been tested and the results are presented in tables and on graphs in this paper. The aim is that after testing the laboratory prototype comes to the data that will be used for the design of industrial product.  相似文献   
26.
Beetroot (Beta vulgaris) pomace, processing by-product from food industry, was investigated in this work as a starting raw material. The contents of phenolics (1.87–11.98 mg GAE/g of dry weight) and betalains (0.75–3.75 mg betalains/g of dry weight) in the extracts were determinated spectrophotometrically. Some individual phenolic compounds, including ferulic, vanillic, p-hydroxybenzoic, caffeic and protocatehuic acids, were identified and quantified by HPLC. The antioxidative activity of beetroot extracts was tested using DPPH, hydroxyl and superoxide anion radicals by ESR spectroscopy. IC50OH (0.05–0.108 mg/ml), IC50DPPH (0.183–0.333 mg/ml), and IC50O2- (0.198–1.000 mg/ml) were calculated. The regression analysis produced moderate to high correlation coefficients between the scavenging activities and phenolics, and some individual phenolic compounds which indicated that beetroot pomace may be used as functional food ingredient. Cell growth effects were determined in MCF7 and MRC-5 cell lines, using SRB assay. IC50 values were in the range of 362.478–503.525 and 383–587.880 μg/ml in MRC-5 and MCF7, respectively.  相似文献   
27.
Composites have been prepared from a phenolic resin (49 vol%) and oxidized PAN fibres (51vol%) with heat treatment to 423, 573, 873, 973, 1073 and 1173 K. Optical and scanning microscopy of polished surfaces indicate a fusing of these two materials into a homogeneous matrix. However, SEM of samples etched with chromic acid shows that the identity of materials is preserved. Initially the resin is less reactive than the PAN fibres. Upon carbonization, the carbon from the resin and the PAN have approximately equal reactivities. Enhanced etching occurs at the curved interfaces of the two carbons. The transverse sections of PAN fibres, HTT>973 K exhibit selective etching suggesting the existence of skin/core components in the fibre. It is the more graphitic components of the skin region which are oxidized preferentially.  相似文献   
28.
Anamorphosis, as a drawing, represents shapes on a surface such that they appear in their natural form only under specific viewing conditions. Although anamorphoses are mainly studied in a historical context, they are currently experiencing a revival. Plane geometric anamorphoses are a specific sub-type of anamorphic drawings. Some practical problems may arise during the design and realization of plane geometric anamorphosis causing the 3D illusionistic effect to be impaired. The aim of this paper is to identify and analyze these problems. In the paper we use parametric analysis to quantify the distortion that may appear because the point of view is offset from the preferred point of view, and to simulate the deviations that can appear because of the errors in onsite realization. The analysis leads to a framework for the design of plane geometric anamorphosis that minimizes the impairment of the anamorphic illusion.  相似文献   
29.
Methodological implications of four accounting procedures applied in multiple authorship treatment relating to author productivity distribution were investigated. The emphasis was given to the individual author rank and inequality pattern of data. It was found that similar pattern of inequality holds in three of the four analysed cases, in spite of the fact that significant changes were observed on the individual level. By introducing the concept of dual approach a plausible interpretation of that phenomenon was obtained.Dedicated to the memory of Michael J. Moravcsik  相似文献   
30.
Alumina based particles were prepared from aluminium chloride hydroxide as starting material by sol-gel technique. One series of particles was doped with ferrous oxide. Both series of particles were calcinated at three different temperatures: 700?°C, 800?°C and 900?°C. Poly(methyl methacrylate), PMMA, was used as a matrix and two different types of alumina based particles were added into the matrix to form the composites. All composites consisted of 3?wt% of alumina based particles. The aim of this study was to examine whether and how the temperature of particle calcination affects the microhardness and mechanical properties of the composite. The particles were characterized by the X-ray diffraction (XRD) and physical absorption methods. The morphology of the composites was examined using a field emission scanning electron microscope (FESEM). The microhardness of composites was measured using a traditional Vickers hardness (HV) method. The mechanical characteristics of obtained composites were determined using tensile test and impact testing.  相似文献   
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