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DNA-hydrolyzing activity of IgG autoantibodies from sera of patients with various types of lymphoproliferative diseases was investigated. The association of DNA-hydrolyzing activity with the antibody (Ab) fraction has been proved by newly developed affinity-capture assay. Study of abzyme incidence in blood tumors and systemic lupus erythematosis (SLE) revealed linkage of anti-DNA Ab catalysts to mature B-cell tumors, and increased probability of DNA-abzymes formation on the background of autoimmune manifestations. These data suggest possible similarity between mechanisms of abzyme formation in SLE and B-cell lymphomas. A new mechanism of formation of DNA-specific catalytic Abs has been proposed based on the increased crossreactivity of polyclonal DNA-abzymes to DNA-depleted nuclear matrix proteins. The possibility of the abzyme production as Ab to the energetically destabilized ground state of the antigen has been discussed. Preliminary results were obtained that indicate the complement-independent cytotoxicity of anti-DNA autoantibodies isolated from blood of patients with SLE and chronic lymphocytic leukemia.  相似文献   
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Conclusions Various O-substituted hydroxylamines were synthesized by the method proposed by us.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1820–1823, August, 1967.  相似文献   
3.
The aim of this study was to measure the shear modulus of the vocal fold in a human hemilarynx, such that the data can be related to direction of applied stress and anatomical context. Dynamic spring rate data were collected using a modified linear skin rheometer using human hemilarynges, and converted to estimated shear modulus via application of a simple shear model. The measurement probe was attached to the epithelial layer of the vocal fold cover using suction. A sinusoidal force of 3g was applied to the epithelium, and the resultant displacement logged at a rate of 1kHz. Force measurement accuracy was 20microg and position measurement accuracy was 4microm. The force was applied in a transverse direction at the midmembranous point between the vocal process and the anterior commissure. The shear modulus of the three female vocal folds ranged from 814 to 1232Pa. The shear modulus of the three male vocal folds ranged from 1021 to 1796Pa. These data demonstrate that it is possible to obtain estimates for the shear modulus of the vocal fold while preserving anatomical context. The modulus values reported here are higher than those reported using parallel plate rheometry. This is to be expected as the tissue is attached to surrounding structures, and is under natural tension.  相似文献   
4.
Powders prepared from nanoporous carbon are promising for creating cold emitters, which are essential to the development of reliable next-generation monitors. The results of an experimental study of the temperature and time dependences of the emission current from nanoporous carbon coatings are reported. It is shown that the stable emission may last at least 20 h under continuous operation if the emission current density does not exceed 0.6 mA/cm2 at room temperature and an accelerating field strength of 800–1200 V/mm. The highest values of the unstable-in-time current density vary from 2.5 to 3.2 mA/cm2.  相似文献   
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Conclusions Some conformational inhibitors were synthesized.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1386–1388, June, 1967.  相似文献   
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Conclusions The dipole moments of isoxazolidone-3 and the methyl ether of acethydroxamic acid have been determined. The hydroxamide group of the latter exists in the trans-conformation in solution.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2754–2757, December, 1967.  相似文献   
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Particle samples were collected in August 2004 both inside and outside Emperor Qin's Terra-Cotta Museum in Xi'an, China. Mass and chemical composition of total suspended particles (JSP, particles with aerodynamic diameter less than-30μm), PM2.5(particles with aerodynamic diameter <2.5μm) were determined. The average levels of indoor PM2.5 and TSP were 108.4 and 172.4 μg·m-3, respectively, with PM2.5 constituting 62.9% of the TSP mass. Sulfate ((32.4±6.2)%), organics ((27.7±8.0)%), and geological material ((12.5±3.4)%) dominated indoor PM2.5, followed by ammonium ((8.9±2.8)%), nitrate ((7.0±2.9)%), and elemental carbon (EC, (3.9±1.5)%). Particle size distribution varied with the number of tourists in the museum. The size of sulfate, organics, EC, nitrate, and ammonium was found to vary in the range of 0.43 to 3.3 μm in fraction. Ion balance indicated that the aerosol was acidic, with insufficient ammonium ions to neutralize the sulfuric and nitric acids. High concentrations of acidic aerosols will erode the Terra-cotta warriors and horses especially in the summer season with high temperature (30℃) and relative humidity (70%) and undesirable solar radiation inside the museum. More attention should be paid to protecting these precious antiques made 2000 years ago.  相似文献   
8.
The angular dependence of the nickel M23VV and of the sulfur L23VV Auger transitions are studied in detail, on clean and sulfur covered Ni(110) surfaces. New experimental data are presented for the anisotropy of both transitions as a function of polar and azimuthai angles of emission. Our model, which incorporates at the same time the multiple scattering effects in the final state wave function and the intrinsic anisotropy of the Auger emitter, is found to give a satisfactory account of the observed auger anisotropy. We find a large sensitivity to the position of the sulfur adsorbed atoms. The best agreement is obtained for the hollow site. slightly less than 0.9 Å above the top nickel layer. This conclusion is consistent with previous LEED and MEIS studies, but does not agree with the long bridge site obtained from quantum chemistry calculations. Moreover the sulfur emitter on this particular Ni(110) face appears to have an intrinsic anisotropy.  相似文献   
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In this work TiO2-SiO2 xerogels were prepared through an ultra low hydrolysis method using titanium and silicon alkoxide. The samples were heat treated to 500°C. The xerogels were characterized using TGA/DTA, FTIR, XRD and TEM. The samples showed the formation of Si–O–Ti bridges by its characteristic vibration within 925–960 cm−1 range. Si–O–Si bond angles were calculated using the central force network model. The TiO2 in all the samples crystallized on heat treatment to 500°C. The crystallite size calculated using the Scherer formula from the XRD was verified from the Transmission Electron Micrograph. Samples heat treated to 350°C remained amorphous and hence could be used as hosts for biomaterials and organic optical materials.  相似文献   
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