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11.
A variety of common environmental pollutants are known to affect the animal behaviour, but the occurrence and extent of pollution-induced behavioural changes in wild populations are practically unknown. Here we show that heavy metal pollution reduces the normal intra-specific aggressive behaviour in wild populations of the wood ant, Formica aquilonia, a dominant territorial ant species in boreal forests. Ants exposed to long-term pollution around a copper smelter showed higher heavy metal concentrations and were less aggressive towards the member of foreign unpolluted colony than the ants from an uncontaminated area. A pollution-related decline in the level of aggressiveness in this keystone general predator species may potentially affect the structure of invertebrate community of boreal and temperate forests. Further studies are needed to find out whether the change in aggressiveness is directly caused by metal toxicity or indirectly via secondary pollution effects, such as changed resource levels.  相似文献   
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Abstract

The growing interest in pilgrimages has led to their being organised in Finland—a traditionally protestant country. They are certainly arranged with the best of intentions. Yet, the ‘St Henrik’s Road’, which purports to follow a mediaeval pilgrim route between Turku and Kokemäki, leaves much to be desired. There is no evidence that such a route ever existed—the hypotheses about it have been accepted much too uncritically. The present propaganda for the pilgrimages along ‘St Henrik’s Road’ lulls the general public into believing that the fragments of the mediaeval landscapes connected with the memories of Henrik, the national saint of Finland, are taken care of. The finances for the management of cultural landscapes are, however, scarce, and other sites more truly connected with the history of the saint, or of greater historical importance, are therefore in danger of being neglected.  相似文献   
14.
The isoflavonoids, equol, formononetin, daidzein, genistein, biochanin A, and O-demethylangolensin (O-DMA), were analyzed from commercial cartons of skimmed Finnish milk by HPLC-diode array detector (DAD)-FL. We found 411 +/- 65 ng/mL of equol and traces of formononetin and daidzein in organic skimmed milk whereas conventionally produced milk contained 62 +/- 16 ng/mL of equol and no formononetin or daidzein.  相似文献   
15.
Drought and heat tolerance of the Sunagoke moss (Racomitrium japonicum) and the low thermal conductivity of the dry moss tissue offer novel greening and insulation possibilities of roofs and walls to mitigate the heat island phenomenon in urban environments. However, damage may appear in the moss panels under humid conditions in Japan. In this study we characterized fungi associated with the damaged areas of the Sunagoke moss panels. Fungi were identified by morphology and internal transcribed spacer (ITS) sequence analysis and tested for pathogenicity on R. japonicum (Grimmiaceae) and an unrelated moss species (Physcomitrella patens; Funariaceae) under controlled conditions. Alternaria alternata, Fusarium avenaceum and Fusarium oxysporum caused severe necrosis and death, whereas Cladosporium oxysporum and Epicoccum nigrum caused milder discoloration or chlorosis in both moss species. The fungi pathogenic on moss were closely related to fungal pathogens described from cultivated vascular plants. Ammonium increased severity of fungal diseases in moss. This study demonstrated that fungi can cause economically significant diseases in cultivated moss and hamper commercial use of the moss panels unless appropriate control methods are developed. Use of a single moss clone to cover large surfaces and the air pollutants such as ammonium may increase the risk for fungal disease problems.  相似文献   
16.
Using an available light source at a wavelength of 254 nm, common acrylate monomers were polymerized without any photoinitiators, which was confirmed using Fourier transform IR (FTIR) spectroscopy, 1H NMR, gel permeation chromatography and fast atom bombardment mass spectrometric measurements. It was found that phenyl acrylate shows higher conversion than n‐ and t‐butyl acrylates. A trifunctional acrylate was also used for UV curing. The cured films were fabricated successfully on different kinds of substrates by using a batch‐ or conveyor‐type irradiation apparatus. It is indicated from FTIR spectral measurements that ca 40%–50% of acryloyl groups are consumed by the photopolymerization. Oxygen concentration in the sample chamber influences the photopolymerization, indicating that the polymerization proceeds via a radical process. © 2018 Society of Chemical Industry  相似文献   
17.
Random mutagenesis on thermophilic 3-isopropylmalate dehydrogenases(IPMDH; EC 1.1.1.85) produced mutant enzymes which adapt tolow temperatures. These mutants had higher activity at lowertemperatures than the wild-type enzyme without losing high thermostability.Here we report three structures of the mutants of Thermus thermophilusIPMDH determined by X-ray diffraction which was adapted to alow-temperature environment. Two of them have unstable coenzymebinding states and the other one probably has a stable substratebinding state. The present research suggests that the adaptationis correlated with the binding of either coenzyme or the substrate.  相似文献   
18.
Chronic low-grade inflammation plays a central role in the pathogenesis of osteoarthritis (OA), and several pro- and anti-inflammatory cytokines have been implicated to mediate and regulate this process. Out of these cytokines, particularly IFNγ, IL-1β, IL-4 and IL-17 are associated with different phenotypes of T helper (TH) cells and macrophages, both examples of cells known for great phenotypic and functional heterogeneity. Chondrocytes also display various phenotypic changes during the course of arthritis. We set out to study the hypothesis of whether chondrocytes might adopt polarized phenotypes analogous to TH cells and macrophages. We studied the effects of IFNγ, IL-1β, IL-4 and IL-17 on gene expression in OA chondrocytes with RNA-Seq. Chondrocytes were harvested from the cartilage of OA patients undergoing knee replacement surgery and then cultured with or without the cytokines for 24 h. Total RNA was isolated and sequenced, and GO (Gene Ontology) functional analysis was performed. We also separately investigated genes linked to OA in recent genome wide expression analysis (GWEA) studies. The expression of more than 2800 genes was significantly altered in chondrocytes treated with IL-1β [in the C(IL-1β) phenotype] with a fold change (FC) > 2.5 in either direction. These included a large number of genes associated with inflammation, cartilage degradation and attenuation of metabolic signaling. The profile of genes differentially affected by IFNγ (the C(IFNγ) phenotype) was relatively distinct from that of the C(IL-1β) phenotype and included several genes associated with antigen processing and presentation. The IL-17-induced C(IL-17) phenotype was characterized by the induction of a more limited set of proinflammatory factors compared to C(IL-1β) cells. The C(IL-4) phenotype induced by IL-4 displayed a differential expression of a rather small set of genes compared with control, primarily those associated with TGFβ signaling and the regulation of inflammation. In conclusion, our results show that OA chondrocytes can adopt diverse phenotypes partly analogously to TH cells and macrophages. This phenotypic plasticity may play a role in the pathogenesis of arthritis and open new therapeutic avenues for the development of disease-modifying treatments for (osteo)arthritis.  相似文献   
19.
Transient receptor potential ankyrin 1 (TRPA1) is an ion channel mainly studied in sensory neurons where it mediates itch, pain and neurogenic inflammation. Recently, some nonneuronal cells have also been shown to express TRPA1 to support inflammatory responses. To address the role of TRPA1 in skin inflammation, we aimed to investigate TRPA1 expression in keratinocytes. HaCaT cells (a model of human keratinocytes) and skin biopses from wild-type and TRPA1 deficient mice were used in the studies. TRPA1 expression in nonstimulated keratinocytes was very low but significantly inducible by the proinflammatory cytokine tumor necrosis factor (TNF) in an nuclear factor kappa B (NF-κB), and mitogen-activated protein (MAP) kinase (p38 and c-Jun N-terminal kinase, JNK)-dependent manner. Interestingly, drugs widely used to treat skin inflammation, the calcineurin inhibitors tacrolimus and cyclosporine and the glucocorticoid dexamethasone, significantly decreased TRPA1 expression. Furthermore, pharmacological inhibition and genetic deletion of TRPA1 reduced the synthesis of TNF-induced monocyte chemoattractant protein 1 (MCP-1) in keratinocytes and mouse skin biopsies. In conclusion, these findings point to an inflammatory role for TRPA1 in keratinocytes and present TRPA1 as a potential drug target in inflammatory skin diseases.  相似文献   
20.
The nonlinear amplitude recording of volume holographic gratings is theoretically and experimentally studied in electrolytically colored potassium bromide crystals. A maximum diffraction efficiency of 10.8% is obtained, which substantially exceeds the 3.7% maximum diffraction efficiency for linear recording.  相似文献   
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