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191.
192.
Dilated cardiomyopathy (DC) and myocarditis (MCD) are still cardiac diseases of unknown etiology and pathogenesis. Due to uncertain natural history of MCD also treatment remains controversial. We observe long-term outcome of 30 pts with biopsy-proved MCD (group I) and 25 pts with DC (group II). The diagnosis of MCD was established on Dallas criteria of MCD. Almost all pts presented symptoms of congestive heart failure. All group I pts were treated with immunosuppressive agents: azathioprine 1.5 mg/kg/d and prednisone with initial dose of 1.5 mg/kg/d. After tapering off 0.75 mg/kg/d of prednisone and initial dose of azathioprine were given up to 6 months. All pts obtained digitalis, diuretics, ACEI, antiarrhythmic drugs if necessary. We studied the survival and clinical status (NYHA class) of treated pts. Clinical improvement was observed in 93% of pts with MCD within 6 months, but 20% of pts deteriorated within the next 6 months. Almost all pts survived 1 year. Out of 30 pts with MCD, 16 pts remain in lower NYHA class (NYHA I-II) between 26 and 69 months of follow-up. Within the group II (DC) 28% of pts died in the first year of observation. Out of 15 pts in 14 pts advanced chronic heart failure (NYHA III-IV) is presented in the end of observation. Echocardiographic parameters of pts with congestive heart failure and biopsy-proved MCD or DC did not differ significantly. We observed correlation between improvement of the LV echocardiographic parameters and improvement of clinical status of treated pts.  相似文献   
193.
Eyeblink conditioning abnormalities have been reported in schizophrenia, but the extent to which these anomalies are evident across a range of delay intervals (i.e., interstimulus intervals; ISIs) is unknown. In addition, the effects of ISI shifts on learning are unknown, though such manipulations can be informative about the plasticity of cerebellar timing functions. Therefore, the primary purpose of the present study was to investigate the interactions between ISI manipulations and learning in schizophrenia. A standard delay eyeblink conditioning procedure with four different interstimulus intervals (ISIs; 250, 350, 550, 850 ms) was employed. Each eyeblink conditioning experiment was immediately followed by another with a different ISI, thus permitting the characterization of conditioned response (CR) learning at one ISI and the extent to which CRs could be generated at a different latency following an ISI shift. Collapsing across all conditions, the schizophrenia group (n = 55) had significantly fewer conditioned responses and longer onset latencies than age-matched controls (n = 55). Surprisingly, shifting to a new ISI had negligible effects on conditioned response rates in both groups. These findings contribute to evidence of robust eyeblink conditioning abnormalities in schizophrenia and suggest impaired cerebellar function, but underscore the need for more research to clarify the source of these abnormalities and their relationship to clinical manifestations of schizophrenia. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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The Eshelby stress (static energy momentum) tensor is derived for bone modelled as an inhomogeneous piezoelectric and piezomagnetic Cosserat (micropolar) medium. The divergence of this tensor is the configurational force felt by material gradients and defects in the medium. Just as in inhomogeneous elastic media, this force is identified with the thermodynamic force for phase transformations, in bone it is the thermodynamic cause of structural transformations, i.e. remodelling and growth. The thermodynamic approach shows that some terms of driving force are proportional to the stress, and some acting on material inhomogeneities are quadratic in the stress-the latter outweigh by far the former. Since inertial forces due to acceleration enter the energy-momentum tensor, it follows that the rate of loading matters and that both tension and compression stimulate growth, which is favoured at heterogeneities.  相似文献   
196.
A device for measuring the kinetic energy of monoenergetic electrons over an energy range of 2–4 MeV is described. The measuring technique is based on an empirical dependence of the kinetic energy on the extrapolated range of electrons in copper. The measuring procedure is presented, and experimental data are compared to the results from studying small-angle electron scattering during planar channeling in silicon. The error in determining the energy is as high as 1%. The device and the empirical dependence are applicable to the energy calibration of electron beam monitors.Translated from Pribory i Tekhnika Eksperimenta, No. 1, 2005, pp. 105–107.Original Russian Text Copyright © 2004 by Korshunov, Lazar.  相似文献   
197.
A three-dimensional, steady state, single phase model is developed to study the mass and charge transfer within a proton exchange membrane (PEM) fuel cell. A single set of conservation equations is used for all PEM fuel cell layers and the governing equations are solved numerically using a finite-volume-based computational fluid dynamics technique. The numerical results for the flow field, species transport and phase potential are presented for two designs, namely a PEM fuel cell with conventional and interdigitated flow fields for the reactant supply.  相似文献   
198.
High–resolution mass spectrometry provides an expeditious technique for positively identifying indigoid dyes of molluscan origin. Indigoids on modern and ancient textile fibres, as well as indigoid mixtures produced by reactions, are discussed. Steam treatment of the fibre or isolation of the dye by solvent extraction permits the analysis by mass spectrometry of dyes which bind more tightly to fibres, such as 6, 6′-dibromoindigotin (C. I. 75800, Natural Vat Dye). The demonstration of the stepwise photolytic denomination of the leuco base of 6, 6′-dibromoindigotin may be of more far-reaching significance in distinguishing between natural and intentional mixtures of indigotin and its dibromo derivative.  相似文献   
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The development and neoplastic progression of human astrocytic tumors appears to result through an accumulation of genetic alterations occurring in a relatively defined order. One such alteration is amplification of the epidermal growth factor receptor (EGFR) gene. This episomal amplification occurs in 40-50% of glioblastomas, which also normally express endogenous receptors. Moreover, a significant fraction of amplified genes are rearranged to specifically eliminate a DNA fragment containing exons 2-7 of the gene, resulting in an in-frame deletion of 801 bp of the coding sequence of the extracellular domain. Here we used retroviral transfer of such a mutant receptor (de 2-7 EGFR) into glioblastoma cells expressing normal endogenous receptors to test whether the mutant receptor was able to augment their growth and malignancy. Western blotting analysis showed that these cells expressed endogenous EGFR of 170 kDa as well as the exogenous de 2-7 EGFR of 140-155 kDa. Although holo-EGFRs were phosphorylated on tyrosine residues only after exposure of the cells to ligand, de 2-7 EGFRs were constitutively phosphorylated. In tissue culture neither addition of EGF nor expression of the mutant EGFR affected the rate of cell growth. However, when cells expressing mutant EGFR were implanted into nude mice subcutaneously or intracerebrally, tumorigenic capacity was greatly enhanced. These results suggest that a tumor-specific alteration of the EGFR plays a significant role in tumor progression perhaps by influencing interactions of tumor cells with their microenvironment in ways not easily assayed in vitro.  相似文献   
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