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1.
Traditional criterions are not sufficient to predict accurately the recurrence of transitional cell carcinoma of the urinary bladder. Therefore, we aimed to evaluate the AgNORs via total AgNOR area/nucleus area (TAA/NA) for each cell as a prognostic parameter, in TCC of urinary bladder. Tumor tissues of 20 consecutive cases of male bladder cancer patients were divided into two groups as middle differentiated (LG) and high grade (HG). The extra-tumoral tissue (ETT) samples of 10 males served as control group. A second control group (HC) consisted of five healthy and normal bladder tissue samples. The 3 microm of sections from each paraffin embedded tumoral, extra-tumoral and normal tissue samples served as patient and control groups. After deparaffinization and rehydratation steps, silver (AgNO(3)) staining of nucleolar organizer regions-associated proteins (AgNORs) was performed. Instead of Giemsa stain, we used Hematoxylin for contra staining. The images of the 100 analyzable nuclei from each tissue sample, transferred by means of a video camera and video capture card from microscope and recorded onto a computer. Software was prepared in Delphi language for analysis. Mean (E+02) TAA/NA values of HC, ETT, LG and HG groups were 6.97+2.80, 5.70+1.82, 7.80+3.22 and 9.24+3.88, respectively. Statistical comparisons have shown significant differences between all groups.In conclusion, mean TAA/NA per cell has a potential to be a prognostic parameter. Therefore, further evaluation of big patient series will be useful.  相似文献   
2.
Concentration of (222)Rn was determined in selected natural spring and tap water samples collected during spring and summer seasons from Kastamonu, Turkey. The aim of this work was to produce a map of the radon concentrations in water sources of the province and to determine any potential radiological risk for the local population. Radon measurements were performed by an AlphaGUARD radon gas analyser. The average radon concentrations were found to vary from 0.39±0.02 to 12.73±0.39?Bq?l(-1) for natural springs and from 0.36±0.04 to 9.29±0.45?Bq?l(-1) for tap water in spring, from 0.50±0.09 to 19.21±1.00?Bq?l(-1) for natural springs and from 0.31±0.03 to 13.14±0.38?Bq?l(-1) for tap water in summer. Furthermore, the results are compared with international recommendations and concentrations reported for other countries. Doses resulting from the consumption of these waters were calculated. The effective dose equivalents due to the intake of the (222)Rn present in these waters are expected to range from 0.93 to 32.54?μSv?y(-1) in summer and from 0.80 to 49.09?μSv?y(-1) in spring.  相似文献   
3.
This paper presents an efficient two nodes finite element with six degrees of freedom per node, capable to model the total behaviour of a helical spring. The formulation, which includes the shear deformation effects, is based on the assumed forces hybrid approach. The resultant forces approximation verifies exactly the resultant equilibrium equations. The developed model proves its accuracy compared with other elements. This element permits to get the distribution of different stresses along the spring and through the wire surface by only one element.  相似文献   
4.
In this paper, the weighted extended basis splines approach in the finite element method is applied to the electrostatic, electromagnetic wave and bioheat problems for inhomogeneous boundary conditions and radially symmetric structures. This new method, which does not need mesh generation, overcomes some of the drawbacks of using meshes and piecewise-uniform or linear trial functions. Two-dimensional radially symmetric electrostatic and electromagnetic wave equations are evaluated. We also attempt to propose a three-dimensional radially symmetric unexposed human eye model for simulating changes in corneal temperature using these new finite elements in conjunction with linear, quadratic and cubic b-splines. Our findings indicate that weighted extended basis spline solutions improve the standard finite element method. The simulation results which are verified using the values reported in the literature, point out to better efficiency in terms of the accuracy level.  相似文献   
5.
We systematically analyze the effects of the use of an inaccurate supercell termination and an insufficient supercell size of plane-wave expansion method on the dispersion and the slow light properties of the photonic crystal waveguides. The inattentive use of supercells of photonic crystal waveguides appeared in the literature is found to be yielding errors in the dispersion and slow light characteristics of the fundamental guided mode of photonic crystal waveguides. In addition, extra modes appear in the photonic band gap of the photonic crystal waveguide due to inaccurate supercell termination. By examining the field distribution of the modes, the extra modes can be determined and removed from the band diagram. The dispersion, group index and bandwidth characteristics are observed to be less affecting from inaccurate supercell termination as the number of rows adjacent to the waveguide increases. Moreover, the dispersion and the group index-frequency curves of the fundamental guided mode of correctly terminated supercells are found to be converging as the lateral row number along the line-defect is increased.  相似文献   
6.
Concentration of 222Rn was determined in selected natural spring and tap water samples collected during spring and summer seasons from Kastamonu, Turkey. The aim of this work was to produce a map of the radon concentrations in water sources of the province and to determine any potential radiological risk for the local population. Radon measurements were performed by an AlphaGUARD radon gas analyser. The average radon concentrations were found to vary from 0.39±0.02 to 12.73±0.39 Bq l?1 for natural springs and from 0.36±0.04 to 9.29±0.45 Bq l?1 for tap water in spring, from 0.50±0.09 to 19.21±1.00 Bq l?1 for natural springs and from 0.31±0.03 to 13.14±0.38 Bq l?1 for tap water in summer. Furthermore, the results are compared with international recommendations and concentrations reported for other countries. Doses resulting from the consumption of these waters were calculated. The effective dose equivalents due to the intake of the 222Rn present in these waters are expected to range from 0.93 to 32.54 μSv y?1 in summer and from 0.80 to 49.09 μSv y?1 in spring.  相似文献   
7.
A series of iron(III) complexes of the tetradentate ligand BPMEN (N,N'-dimethyl-N,N'-bis(2-pyridylmethyl)ethane-1,2-diamine) were prepared and structurally characterized. Complex [Fe(2)(mu-O)(mu-OH)(BPMEN)(2)](ClO(4))(3) (1) contains a (mu-oxo)(mu-hydroxo)diiron(III) diamond core. Complex [Fe(BPMEN)(urea)(OEt)](ClO(4))(2) (2) is a rare example of a mononuclear non-heme iron(III) alkoxide complex. Complexes [Fe(2)(mu-O)(mu-OC(NH(2))NH)(BPMEN)(2)](ClO(4))(3) (3) and [Fe(2)(mu-O)(mu-OC(NHMe)NH)(BPMEN)(2)](ClO(4))(3) (4) feature N,O-bridging deprotonated urea ligands. The kinetics and equilibrium of the reactions of 1 with ligands L (L = water, urea, 1-methylurea, 1,1-dimethylurea, 1,3-dimethylurea, 1,1,3,3-tetramethylurea, and acetamide) in acetonitrile solutions were studied by stopped-flow UV-vis spectrophotometry, NMR, and mass spectrometry. All these ligands react with 1 in a rapid equilibrium, opening the four-membered Fe(III)(mu-O)(mu-OH)Fe(III) core and forming intermediates with a (HO)Fe(III)(mu-O)Fe(III)(L) core. The entropy and enthalpy for urea binding through oxygen are DeltaH degrees = -25 kJ mol(-1) and DeltaS degrees = -53.4 J mol(-1) K(-1) with an equilibrium constant of K(1) = 37 L mol(-1) at 25 degrees C. Addition of methyl groups on one of the urea nitrogen did not affect this reaction, but the addition of methyl groups on both nitrogens considerably decreased the value of K(1). An opening of the hydroxo bridge in the diamond core complex [Fe(2)(mu-O)(mu-OH)(BPMEN)(2)] is a rapid associative process, with activation enthalpy of about 60 kJ mol(-1) and activation entropies ranging from -25 to -43 J mol(-1) K(-1). For the incoming ligands with the -CONH(2) functionality (urea, 1-methylurea, 1,1-dimethylurea, and acetamide), a second, slow step occurs, leading to the formation of stable N,O-coordinated amidate diiron(III) species such as 3 and 4. The rate of this ring-closure reaction is controlled by the steric bulk of the incoming ligand and by the acidity of the amide group.  相似文献   
8.
The current techniques for monitoring and diagnostics of rotating machines to their conditional predictive maintenance mainly are based on vibration monitoring. In this research, experimental and theoretical methods to predict the tonal noise of a faulty fan are developed and validated. These methods can be used on identifying defects of an axial fan based on an acoustic monitoring in situations where it is necessary to operate remotely due to the inaccessibility of the areas of event defects.  相似文献   
9.
In this article we obtain asymptotic formulas for the eigenvalues and eigenfunctions of the non-self-adjoint operator generated in L 2 m [0, 1] by the Sturm-Liouville equation with m × m matrix potential and the boundary conditions which, in the scalar case (m = 1), are strongly regular. Using these asymptotic formulas, we find a condition on the potential for which the root functions of this operator form a Riesz basis.  相似文献   
10.
Nanofibers featuring functional nanoassemblies show great promise as enabling constituents for a diverse range of applications in areas such as tissue engineering, sensing, optoelectronics, and nanophotonics due to their controlled organization and architecture. An infusion gyration method is reported that enables the production of nanofibers with inherent biological functions by simply adjusting the flow rate of a polymer solution. Sufficient polymer chain entanglement is obtained at Berry number > 1.6 to make bead‐free fibers integrated with gold nanoparticles and proteins, in the diameter range of 117–216 nm. Integration of gold nanoparticles into the nanofiber assembly is followed using a gold‐binding peptide tag genetically conjugated to red fluorescence protein (DsRed). Fluorescence microscopy analysis corroborated with Fourier transform infrared spectroscopy (FTIR) data confirms the integration of the engineered red fluorescence protein with the nanofibers. The gold nanoparticle decorated nanofibers having red fluorescence protein as an integral part keep their biological functionality including copper‐induced fluorescence quenching of the DsRed protein due to its selective Cu+2 binding. Thus, coupling the infusion gyration method in this way offers a simple nanoscale assembly approach to integrate a diverse repertoire of protein functionalities into nanofibers to generate biohybrid materials for imaging, sensing, and biomaterial applications.

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