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1.
We previously found that short-term treatment (week 8 to 12 after injury) with high-dose angiotensin receptor blocker (ARB) induced the regression of existing glomerulosclerosis in 5/6 nephrectomy rats. We therefore assessed the effects of long-term intervention with ARB vs. nonspecific antihypertensives in this study. Adult rats underwent 5/6 nephrectomy and renal biopsy 8 weeks later. The rats were then divided into three groups with equivalent renal function and glomerular sclerosis and treated with high-dose losartan (ARB), nonspecific antihypertensive triple-therapy (TRX), or left untreated (Control) until week 30. We found that blood pressure, serum creatinine levels, and glomerulosclerosis were lower at sacrifice in ARB and TRX vs. Control. Only ARB reduced proteinuria and maintained the density of WT-1-positive podocytes. Glomerular tufts showed more double-positive cells for CD44, a marker of activated parietal epithelial cells, and synaptopodin after ARB vs. TRX or Control. ARB treatment reduced aldosterone levels. ARB-treated rats had significantly improved survival when compared with TRX or Control. We conclude that both long-term ARB and triple-therapy ameliorate progression, but do not sustain the regression of glomerulosclerosis. ARB resulted in the superior preservation of podocyte integrity and decreased proteinuria and aldosterone, linked to increased survival in the uremic environment.  相似文献   
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The influence of fluid-film bearings on the parametric instability of asymmetric shafts is investigated. Since fluid-film bearings may have non-isotropic stiffness and damping, the system equations are time-varying coefficients in a rotating reference frame and the complete solution of transition curves includes coupled modes. Thus, the analytical modal method provided by our previous studies has been modified in this part for the determination of approximate solutions from a truncated Hill's determinant. In numerical examples, a plain cylindrical type and a tilting four-pad type are considered to estimate the effects of bearing parameters concerning static load, oil viscosity, and clearance on unstable regions.  相似文献   
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A porous silicon Al Schottky barrier diode shows differential negative resistance. The thin wires in porous silicon have much lower electron mobility than that of thick wires, due to electron surface scattering from space confinement. The energy of carriers in thick wires increases with applied bias. Some carriers can overcome the conduction-band discontinuity and flow into the thin wires. The negative differential resistance comes from the mobility difference between thick wires and thin wires in porous silicon.  相似文献   
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In this paper, some algebraic properties of autodense languages and pure autodense languages are studied. We also investigate the algebraic properties concerning anti-autodense languages. The family of anti-autodense languages contains infix codes, comma-free codes, and some subfamilies of new codes which are anti-autodense prefix codes, anti-autodense suffix codes and anti-autodense codes. The relationships among these subfamilies of new codes are investigated. The characterization of L n , n ≥ 2, which are anti-autodense is studied.  相似文献   
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Between 1985 and 1994, 1223 patients with malleolar fractures of the ankle were treated by open reduction and internal fixation with absorbable pins and screws, of whom 74 (6.1%) had an obvious inflammatory foreign-body reaction to the implants. Of these 74, ten later developed moderate to severe osteoarthritis of the ankle despite no evidence of incongruity of the articular surface. The implants used in these patients were made from polyglycolide, polylactide or glycolide-lactide copolymer. The joint damage seemed to be due to polymeric debris entering the articular cavity through an osteolytic extension of an implant track. The ten patients had a long clinical course which included a vigorous local foreign-body reaction, synovial irritation and subsequent degeneration. At a follow-up of three to nine years, ankle arthrodesis had been necessary in two patients and is being considered for another two. The incidence of these changes in the whole series was 0.8%, which is not high, but awareness of this possible late complication is essential.  相似文献   
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This study presents a modification of the Jones–Harris method (JHM) for the determination of deflection in deep-groove ball bearings. The finite element method (FEM) and curve fitting have been utilized to modify the load–deflection relationships of Hertz contact formulas in JHM. Several cases of deep-groove bearings are simulated to determine contact deflection. Results obtained from the modified JHM (MJHM) are more accurate than the JHM results demonstrated by the comparison between FEM and experimental results.  相似文献   
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In this paper, based on the phase-position perturbation method, an innovative optimal adaptive antenna technique is proposed, where the deduced radiation pattern formulas available for searching optimal solutions are used to search the optimal weighting vector. The optimal radiation pattern designs of adaptive antenna are studied by the phase-position perturbation method. Memetic algorithms are used to search the optimal weighting vector of the phase-position perturbations for the array factor. The design for an optimal radiation pattern of an adaptive antenna can not only adjustably suppress the interferers by placing nulls at the directions of the interfering sources, but at the same time provide a maximum main lobe in the direction of the desired signal, i.e., to maximize the signal-to-interference ratio. To achieve this goal, a new convergent method, referred to as the two-way convergent method for memetic algorithms, is proposed. The memetic algorithm combines a genetic algorithm and local search heuristics to solve combinatorial optimization problems. The memetic algorithm is a kind of improved type of the traditional genetic algorithm. By using a local search procedure, it can avoid the shortcomings of the traditional genetic algorithm, whose termination criteria are set up by using the trial and error method. This proposed method is also able to solve the multipath problem, which exists at the same time in this communication system. The optimal radiation pattern concept can be implemented in practical wireless communication systems. Simulation results are also given in this paper.  相似文献   
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