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91.
The volume of publicly available data in biomedicine is constantly increasing. However, these data are stored in different formats and on different platforms. Integrating these data will enable us to facilitate the pace of medical discoveries by providing scientists with a unified view of this diverse information. Under the auspices of the National Center for Biomedical Ontology (NCBO), we have developed the Resource Index – a growing, large-scale ontology-based index of more than twenty heterogeneous biomedical resources. The resources come from a variety of repositories maintained by organizations from around the world. We use a set of over 200 publicly available ontologies contributed by researchers in various domains to annotate the elements in these resources. We use the semantics that the ontologies encode, such as different properties of classes, the class hierarchies, and the mappings between ontologies, in order to improve the search experience for the Resource Index user. Our user interface enables scientists to search the multiple resources quickly and efficiently using domain terms, without even being aware that there is semantics “under the hood.”  相似文献   
92.
Expertise recognition is challenging in teamwork, particularly in intercultural collaboration. This research seeks to investigate how cultural differences in communication styles may affect expertise recognition and influence in face-to-face (FtF) versus text-based computer-mediated communication (CMC). Using experimental intercultural groups, we found that in FtF groups East Asian experts had a lower participation rate, and were perceived as less competent, less confident, and less influential than experts from Western culture. No such differences occurred in CMC. The results support mediated moderation effect of perceived confidence on expert influence such that changes in perceptions of Chinese and American experts' confidence accounted for their different levels of influence in CMC versus FtF. No such effect was found with participation rate.  相似文献   
93.
The paper deals with the theoretical and practical aspects of improving regulatory and technical framework for assuring the quality and safety of metal structures and their protective coatings under the exposure of corrosive environment. Methodological approach has been developed to managing technological safety, assessing the risks of corrosion failures, and extension of an industrial facility's life based on company standards taking into account the requirements for safe operation of buildings and installations. Basic provisions of the method of limit states design have been analyzed to determine: design characteristics of corrosion impacts, computational models and design cases for affirming compliance of corrosion resistance, and durability and maintainability of structures and their protective coatings. Presented are practical examples of justifying the choice of means of primary and secondary protection, taking into account classification of the established levels of facility corrosion hazard. On the basis of limit state design principles, logistical control- and decision-making system is generated for reliability assurance of steel structures and protective coatings. Assessment criteria are specified for the risks with the use of the materials and technologies of primary and secondary corrosion protection.  相似文献   
94.
Two new techniques were recently developed in these laboratories for fabrication of protein microarrays: electrospray deposition of dry proteins and covalent linking of proteins from dry deposits to a dextran-grafted surface. Here we apply these techniques to simultaneously fabricate 1200 identical microarrays. Each microarray, 0.6 x 0.6 mm2 in size, consists of 28 different protein antigens and allergens deposited as spots, 30-40 microm in diameter. The ability of the microarrays to detect IgG antibodies in plasma samples from mice immunized with different sets of antigens and IgE antibodies in human plasmas was examined using ELISA. Comparison of the microarray-based ELISAs with standard ELISAs in microtiter plates established that both techniques provided identical responses in 88% of all the antibody/antigen interactions tested. Both techniques showed similar antibody detecting sensitivity defined by the maximum dilution of serum at which a reliable signal distinguishable from the background was obtained.  相似文献   
95.
96.
    
Many proteins form amyloid fibrils only under conditions when the probability of transition from a native (structured, densely packed) to an intermediate (labile, destabilized) state is increased. It implies the assumption that some structural intermediates are more convenient for amyloid formation than the others. Hence, if a mutation affects the protein folding pathway, one should expect that this mutation could affect the rate of amyloid formation as well. In the current work, we have compared the effects of amino acid substitutions of bovine carbonic anhydrase II on its unfolding pathway and on its ability to form amyloids at acidic pH and an elevated temperature. Wild-type protein and four mutant forms (L78A, L139A, I208A, and M239A) were studied. We analyzed the change of the protein unfolding pathway by the time-resolved fluorescence technique and the process of amyloid formation by thioflavin T fluorescence assay and electron microscopy. It was revealed that I208A substitution accelerates amyloid formation and affects the structure of the late (molten globule-like)-intermediate state of carbonic anhydrase, whereas the other mutations slow down the growth of amyloids and have either no effect on the unfolding pathway (L78A, L139A) or alter the conformational states arising at the early unfolding stage (M239A).  相似文献   
97.
    
This work investigated the effect of thyroxine on the biogenesis and quality control system of rat liver mitochondria. Chronic administration of thyroxine to experimental animals induced hyperthyroidism, which was confirmed by a severalfold increase in serum-free triiodothyronine and thyroxine concentrations. The uptake of oxygen was found to increase with a decrease in ADP phosphorylation efficiency and respiratory state ratio. Electron microscopy showed 36% of liver mitochondria to be swollen and approximately 18% to have a lysed matrix with a reduced number of cristae. Frequently encountered multilamellar bodies associated with defective mitochondria were located either at the edge of or inside the organelle. The number, area and perimeter of hyperthyroid rat mitochondria increased. Administration of thyroxine increased mitochondrial biogenesis and the quantity of mitochondrial DNA in liver tissue. Mitochondrial dynamics and mitophagy changed significantly. The data obtained indicate that excess thyroid hormones cause a disturbance of the mitochondrial quality control system and ultimately to the incorporation of potentially toxic material in the mitochondrial pool.  相似文献   
98.
    
In the immunotherapy based on immune checkpoint inhibition (IC), additional ICs are being studied to increase its effectiveness. An almost unstudied feature is the possible co-expression of ICs, which can determine the therapeutic efficacy of their inhibition. For the selection of promising ICs, information on the association of their expression with cancer development may be essential. We have obtained data on the expression correlation of ADAM17, PVR, TDO2, CD274, CD276, CEACAM1, IDO1, LGALS3, LGALS9, and HHLA2 genes in gastric cancer (GC). All but one, TDO2, have other IC genes with co-expression at some stage. At the metastatic stage, the expression of the IDO1 does not correlate with any other gene. The correlations are positive, but the expressions of the CD276 and CEACAM1 genes are negatively correlated. The expression of TDO2 and LGALS3 is associated with GC metastasis. The expression of TDO2 four-fold higher in metastatic tumors than in non-metastatic tumors, but LGALS3 was two-fold lower. The differentiation is associated with IDO1. The revealed features of TDO2, with a significant increase in expression at the metastatic stage and the absence of other IC genes with correlated expression indicates that the prospect of inhibiting TDO2 in metastatic GC. IDO1 may be considered for inhibition in low-differentiated tumors.  相似文献   
99.
    
This study is aimed to explore the capacity of metal nanoparticles (NPs) iron, zinc, copper and their combinations introduced in the Murashige–Skoog (MS) nutrient medium (NM) to affect the growth and development of tomato plants (Solanum lycopersicum L.). NPs were prepared by a flow‐levitation method. Metal NPs were characterised by transmission and scanning electron microscopy, X‐ray phase analysis. Average NPs diameters were: iron – 27.0 nm, zinc – 54.0 nm, copper – 79.0 nm. MS NM was modified by substitution of common metal sulphates by neutral metal NPs instead of salts. Tomato seedlings cultivation on NM MS with NPs instead of salts assures improved seedling parameters (root length and root activity) in comparison with plants grown on standard MS. Venice cultivar tomato seedlings grown on NM with metal NPs demonstrated an increase in: seed germination by 10–180%, root length by 10–20%, and root activity by 10 –125%. After 45 days of cultivation, tomato seedlings were transplanted in a greenhouse and were grown up to the harvest. Effects in seed germination and increase of crop mass depended on metal nature and NPs concentration.Inspec keywords: copper, crops, nanoparticles, scanning electron microscopy, greenhouses, agriculture, nanofabrication, iron, zinc, transmission electron microscopyOther keywords: size 27.0 nm, size 54.0 nm, size 79.0 nm, time 45.0 d, Fe, Zn, Cu, metal nanoparticles, iron, zinc, tomato plants growth, Solanum lycopersicum L., flow‐levitation method, scanning electron microscopy, X‐ray phase analysis, metal sulphates, tomato seedlings cultivation, Murashige‐Skoog nutrient medium, Venice cultivar, copper, transmission electron microscopy, seed germination, greenhouse, seedlings transplantion  相似文献   
100.
    
Magnetite nanoparticles (Fe3O4 NPs) with peroxide-containing polymer shell have been synthesized using the method of coprecipitation from the mixture solutions of Fe (II) and Fe (III) salts in the presence of peroxide-containing copolymer (PCC). Polymer shell presence has been proved by elemental and complex thermal analysis. Synthesized Fe3O4 NPs possess superparamagnetic properties. Their specific saturation magnetization decreases gradually from 65 to 54 A·m2·kg−1 with increasing PCC concentration owing to the surface spin pinning effect caused by a polymer shell. The average sizes of Fe3O4 NPs estimated from the data of XRD analysis and magnetic measurements are in the range of 9–12 nm. The NP sizes determined by the DLS method lie in the range of 150–270 nm; this result is significantly larger than the sizes estimated by the two aforementioned methods evidencing a tendency for Fe3O4 NPs toward self-association. Cross-linked composite films based on polyvinyl alcohol have been obtained via radical curing initiated by the PCC shell of nanoparticles. The resulting composite films are magnetically sensitive films with rather high physico-mechanical properties (tensile strength reaches 48–67 MPa and relative elongation – 4%–21% depending on cross-linking degree), a priori non-toxic and biocompatible, which makes them promising materials for various applications.  相似文献   
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