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71.
Sea buckthorn (Elaeagnus rhamnoides (L.) A. Nelson) is a shrub growing in coastal areas. Its organs contain a range of bioactive substances including vitamins, fatty acids, various micro and macro elements, as well as phenolic compounds. Numerous studies of sea buckthorn have found it to have anticancer, anti-ulcer, hepatoprotective, antibacterial, and antiviral properties. Some studies suggest that it also affects the hemostasis system. The aim of the study was to determine the effect of six polyphenols rich and triterpenic acids rich fractions (A–F), taken from various organs of sea buckthorn, on the activation of blood platelets using whole blood, and to assess the effect of the tested fractions on platelet proteins: fraction A (polyphenols rich fraction from fruits), fraction B (triterpenic acids rich fraction from fruits), fraction C (polyphenols rich fraction from leaves), fraction D (triterpenic acids rich fraction from leaves), fraction E (polyphenols rich fraction from twigs), and fraction F (triterpenic acids rich fraction from twigs). Hemostasis parameters were determined using flow cytometry and T-TAS (Total Thrombus-formation Analysis System). Additionally, electrophoresis was performed under reducing and non-reducing conditions. Although all tested fractions inhibit platelet activation, the greatest anti-platelet activity was demonstrated by fraction A, which was rich in flavonol glycosides. In addition, none of the tested fractions (A–F) caused any changes in the platelet proteome, and their anti-platelet potential is not dependent on the P2Y12 receptor.  相似文献   
72.
Silver nanoparticles (AgNPs) are the one of the most extensively used nanomaterials. The strong antimicrobial properties of AgNPs have led to their use in a wide range of medical and consumer products. Although the neurotoxicity of AgNPs has been confirmed, the molecular mechanisms have not been extensively studied, particularly in immature organisms. Based on information gained from previous in vitro studies, in the present work, we examine whether ionotropic NMDA glutamate receptors contribute to AgNP-induced neurotoxicity in an animal model of exposure. In brains of immature rats subjected to a low dose of AgNPs, we identified ultrastructural and molecular alterations in the postsynaptic region of synapses where NMDA receptors are localized as a multiprotein complex. We revealed decreased expression of several NMDA receptor complex-related proteins, such as GluN1 and GluN2B subunits, scaffolding proteins PSD95 and SynGAP, as well as neuronal nitric oxide synthase (nNOS). Elucidating the changes in NMDA receptor-mediated molecular mechanisms induced by AgNPs, we also identified downregulation of the GluN2B-PSD95-nNOS-cGMP signaling pathway which maintains LTP/LTD processes underlying learning and memory formation during development. This observation is accompanied by decreased density of NMDA receptors, as assessed by a radioligand binding assay. The observed effects are reversible over the post-exposure time. This investigation reveals that NMDA receptors in immature rats are a target of AgNPs, thereby indicating the potential health hazard for children and infants resulting from the extensive use of products containing AgNPs.  相似文献   
73.
The C-terminal-fragments of alpha1-antitrypsin (AAT) have been identified and their diverse biological roles have been reported in vitro and in vivo. These findings prompted us to develop a monoclonal antibody that specifically recognizes C-36 peptide (corresponding to residues 359–394) resulting from the protease-associated cleavage of AAT. The C-36-targeting mouse monoclonal Immunoglobulin M (IgM) antibody (containing κ light chains, clone C42) was generated and enzyme-linked immunosorbent assay (ELISA)-tested by Davids Biotechnologie GmbH, Germany. Here, we addressed the effectiveness of the novel C42 antibody in different immunoassay formats, such as dot- and Western blotting, confocal laser microscopy, and flow cytometry. According to the dot-blot results, our novel C42 antibody detects the C-36 peptide at a range of 0.1–0.05 µg and shows no cross-reactivity with native, polymerized, or oxidized forms of full-length AAT, the AAT-elastase complex mixture, as well as with shorter C-terminal fragments of AAT. However, the C42 antibody does not detect denatured peptide in SDS-PAGE/Western blotting assays. On the other hand, our C42 antibody, unconjugated as well as conjugated to DyLight488 fluorophore, when applied for immunofluorescence microscopy and flow cytometry assays, specifically detected the C-36 peptide in human blood cells. Altogether, we demonstrate that our novel C42 antibody successfully recognizes the C-36 peptide of AAT in a number of immunoassays and has potential to become an important tool in AAT-related studies.  相似文献   
74.
New analytical laboratory tools for qualitative analysis of alternative and renewable solid biofuels have been developed. The primary target of this research was to develop and then validate a rapid method for semi-quantitative and qualitative analyses of the second-generation solid biofuels. X-ray fluorescence spectroscopy (XRF) was used in combination with a two-step, multivariate modelling procedure. First, soft independent modelling of class analogies (SIMCA) and classification and regression trees (C&RT) were applied to develop and validate the classifier, which enabled different biomass origins (agrarian biomass, forest biomass and furniture waste) and different possible sources of contamination (plastic, fossil fuels and lignin-cellulose after biomass acid hydrolysis) to be distinguished. Next, the model attempted to predict the concentration of individual components using partial least-squares regression (PLSR) models. In our study, we compared C&RT and SIMCA, and the classification models (algorithms) constructed by the C&RT method were characterised as having better properties than those based on SIMCA. The C&RT classification algorithm was able to predict the origin of biomass sources with a non-error rate greater than 95%. For predictions of the addition type, the non-error rate was greater than 91%. The developed methods can rapidly and adequately determine (qualitatively) the origin of biofuels and indicate possible sources of contamination.  相似文献   
75.
Gender differences in cognitive outcome were examined in children born prematurely who had incurred early cerebral lesions and in a high-risk comparison group. The boys and girls, who had suffered perinatal intracranial hemorrhage (the most common neurological insult in the preterm infant) were similar in their antenatal, perinatal, and postnatal course, as well as in their sociofamilial attributes. After statistical adjustment to account for the extent of the insult, a significant gender difference in cognitive recovery was observed in the lesion group. Girls outperformed boys by about half a standard deviation on standardized intelligence tests. No gender differences were observed in the comparison group. The implications of the results for theories and empirical findings on gender differences in vulnerability to deviation from normal development are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
76.
77.
Spin‐polarized charge transfer at the interface between a ferromagnetic (FM) metal and a molecule can lead to ferromagnetic coupling and to a high spin polarization at room temperature. The magnetic properties of these interfaces can not only alter those of the ferromagnet but can also stabilize molecular spin chains with interesting opportunities toward quantum computing. With the aim to enhance an organic spintronic device's functionality, external control over this spin polarization may thus be achieved by altering the ferromagnet/molecule interface's magnetic properties. To do so, the magnetoelectric properties of an underlying ferroelectric/ferromagnetic interface are utilized. Switching the ferroelectric polarization state of a PbZr0.2Ti0.8O3 (PZT) bottom layer within a PZT/Co/FePc‐based (Pc ‐ phthalocyanine) device alters the X‐ray magnetic circular dichroism of the Fe site within the phthalocyanine molecular top layer. Thus, how to electrically alter the magnetic properties of an interface with high spin polarization at room temperature is demonstrated. This expands electrical control over spin‐polarized FM/molecule interfaces, which is first demonstrated using ferroelectric molecules, to all molecular classes.  相似文献   
78.
Critical analysis of light depolarization technique (LDT) widely used in polymer crystallization kinetics is presented. It is demonstrated, that intensity of light depolarized on a system of birefringent crystals cannot be treated as a measure of volume fraction of crystalline phase (degree of crystallinity). Intensity of light depolarized in a polycrystalline system is a non-linear function of the product of the degree of crystallinity and function of average crystal dimensions. Closed-form expression for depolarization ratio is derived and the range of conditions where linear approximation is acceptable is discussed.In spite of interpretational weaknesses, further development of light depolarization technique seems to be justified by potentially short response time. LDT may appear useful for studying rapid crystallization processes (above 1 kHz sampling frequency), which cannot be followed by measurements of density, X-ray diffraction or calorimetry. However, the LDT data either have to be combined with independent measurements of crystal thickness, or treated as a ‘crystallization characteristic’ per se, quantitatively inconsistent with calorimetric, volumetric or X-ray diffraction data.  相似文献   
79.
Innovation is an important source of growth for many companies. It is also challenging, as it may require that the companies build a new position in the supply chain. The literature is devoid of analysis of different ways to build such positions in the construction industry. The purpose here is to explore the challenges involved in implementing innovations that require companies to establish new positions in a construction supply chain. Three in‐depth case studies in the Swedish timber housing industry illustrate different challenges that arise with the different modes of repositioning of organic growth, collaboration and acquisition, and with moving either backward or forward in the supply chain. Organic growth is a slow process that prevents companies from taking a first‐mover advantage. Acquisitions can involve difficulties with exploiting acquired competences. Collaboration brings the risks of diversity of interests and transient solutions. Furthermore, and as shown in the cases studied, challenges are associated with pre‐existing competencies and relationships, with technology‐oriented companies facing customer‐related difficulties and market‐oriented companies mainly facing ones involving technological solutions. The construction industry’s idiosyncrasies amplify these challenges, as its fragmentation makes it difficult to connect with external companies at new positions. Stronger ties with business partners are likely to enable construction companies to exploit more easily innovations that require repositioning in the supply chain.  相似文献   
80.
Adult feeding intensity, oviposition, and larval development of Sitophilus granarius (Coleoptera: Curculionidae) were observed on grain from three Polish wheat varieties (Begra, Korweta, and LGR 896/64a) washed with petroleum ether to remove cuticular lipids. Extraction of lipids did not cause any statistically significant changes in the physicochemical, biochemical and technological (milling, rheological and baking) properties of the wheat grain studied. Wheat grain washed with petroleum ether did not show any visible changes in the surface and morphology of the outer layer of the wheat grain. However, differences were noted in the microstructure of the kernel surface. Grain with a thicker seed coat (LGR 896/64a) was infested at a lower rate than the other varieties. Of the 18 hydrocarbons extracted from the grain surface, three compounds - n-heptacosane (C27), n-nonacosane (C29) and n-hentriacontane (C31) - were found in significant amounts. In general, beetles produced 64-95% less dust and laid 7-16% fewer eggs in kernels from which cuticular lipids had been removed. This implies that these compounds have a major role in food selection and the search for an oviposition site prior to grain infestation.  相似文献   
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