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71.
The smear‐ripened soft cheeses are characterised by a surface orange‐red‐brown colour, which has a microbial origin. For a long time, this colouration was mainly imputed to Brevibacterium linens. However, the latest published works, based on molecular biology, have shown a minor role for this bacterium. This study shows the results obtained with an industrial cheese named Vieux‐Pané, which is characterised by the presence of carotenoids from Brevibacterium linens group at its surface. This demonstrates that, under certain conditions, the Brevibacterium linens group (Brevibacterium linens and Brevibacterium aurantiacum sp. nov.) is able to produce pigments and to colour cheeses effectively.  相似文献   
72.
The 4-Hydroxy-2,6-dioxabicyclo(3,3,0)Octan-8-one[1S,4S,5R], monoketone, is obtained by catalytic oxidation of isosorbide—or 2,6-dioxabicyclo(3,3,0)4,8-octandiol[1R,4S,5R,8R]—in an aqueous solution with a stream of oxygen and in the presence of a platinum on carbon catalyst. Setting up sequentially two experimental designs made it possible to study the three main factors which influence the monoketone formation in the case of two reactors of different size and profile. Optimisation of selective and/or quantitative conditions is carried out by comparing response surfaces. Several functional configurations for a discontinuous reactor under agitation are proposed as a function of the constraints chosen.  相似文献   
73.
Evidence from psychological research has shown the importance of fear on attitude and/or behavior change. The experiment hereby quoted tests the influence of commitment (high vs. low) on an attempt of persuasive message for a forthcoming effect, that is, after reading an antialcohol message to subjects. The idea consists in inducing alcohol consumers toward modifying their attitude and behavioral intentions toward alcohol. As expected, the high committed drinkers (i.e., regular drinkers) resist persuasion (on the level of both attitude and intention). The low committed drinkers (i.e., occasional drinkers) do not resist persuasion but adopt further on a more favorable attitude toward alcohol. The drinkers who had read a strongly threatening, yet at the same time strongly reassuring, message express the strongest intention to reduce their alcohol consumption. Results are described with reference to Witte's (1998) extended parallel process model. A new perspective is presented at the end of our paper, that is, toward a "committing communication." (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
74.
Payne RJ  Peyrot F  Kerbarh O  Abell AD  Abell C 《ChemMedChem》2007,2(7):1015-1029
The in silico design, synthesis, and biological evaluation of ten potent type II dehydroquinase inhibitors are described. These compounds contain an anhydroquinate core, incorporated as a mimic of the enolate reaction intermediate. This substructure is attached by a variety of linking units to a terminal phenyl group that binds in an adjacent pocket. Inhibitors were synthesised from (-)-quinic acid using palladium-catalysed Stille and carboamidation chemistry. Several inhibitors exhibited nanomolar inhibition constants against type II dehydroquinases from Streptomyces coelicolor and Mycobacterium tuberculosis. These are among the most potent inhibitors of these enzymes reported to date.  相似文献   
75.
We have designed a mass stable reporter (msr) tag with m/z over 500, trifluoroacetyl(alpha,alpha-diethyl)Gly-Lys(Nepsilonbiotin)-(D)Lys-Cys, for the quantification of the uptake and study of the degradation processes of cell-penetrating peptides (CPP), by matrix assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. This tag was found stable in cell lysis conditions. Using a quantitative MALDI-TOF mass spectrometry analysis based method, an accurate tracking of a new CPP and of its degradation products could be done. (1) The new msr(W/R) nonapeptide (H-RRWWRRWRR-NH2) enters chinese hamster ovary (CHO) K1 cells with a kinetic reaching a steady state after 30-60 min of incubation. This plateau was stable for 4 h and decreased slowly afterward. (2) The peptide msr(W/R) nonapeptide was not cytotoxic over 48 h incubation with CHO cells. (3) After 1 h incubation, the msr(W/R) nonapeptide accumulated with a 3-fold higher concentration than the extracellularly added concentration (7.5 microM). (4) The intracellular quantification was accurate with less than 3% of the quantified peptide being potentially membrane-bound. (5) There was no leakage of the full-length CPP outside the cells. And, finally, (6) analysis of the degradation process of this new CPP suggests that the peptide did not traffick to lysosomes.  相似文献   
76.
Dietary supplementation with marine omega‐3 polyunsaturated fatty acids (n‐3 PUFA) can have beneficial effects on a number of risk factors for cardiovascular disease (CVD). We compared the effects of two n‐3 PUFA rich food supplements (freeze‐dried Odontella aurita and fish oil) on risk factors for CVD. Male rats were randomly divided into four groups of six animals each and fed with the following diets: control group (C) received a standard diet containing 7 % lipids; second group (HF high fat) was fed with a high‐fat diet containing 40 % lipids; third group (HFFO high fat+fish oil) was fed with the high‐fat diet supplemented with 0.5 % fish oil; and fourth group (HFOA high fat+O. aurita) received the high‐fat diet supplemented with 12 % of freeze‐dried O. aurita. After 8 weeks rats fed with the high‐fat diet supplemented with O. aurita displayed a significantly lower bodyweight than those in the other groups. Both the microalga and the fish oil significantly reduced insulinemia and serum lipid levels. O. aurita was more effective than the fish oil in reducing hepatic triacyglycerol levels and in preventing high‐fat diet‐induced steatosis. O. aurita and fish oil also reduced platelet aggregation and oxidative status induced by high fat intake. After an OA supplementation, the adipocytes in the HFOA group were smaller than those in the HF group. Freeze‐dried O. aurita showed similar or even greater biological effects than the fish oil. This could be explained by a potential effect of the n‐3 PUFA but also other bioactive compounds of the microalgae.  相似文献   
77.
Functionalized oligoribonucleotides are essential tools in RNA chemical biology. Various synthetic routes have been developed over recent years to conjugate functional groups to oligoribonucleotides. However, the presence of the functional group on the oligoribonucleotide backbone can lead to partial or total loss of biological function. The limited knowledge concerning the positioning of functional groups therefore represents a hurdle for the development of oligoribonucleotide chemical tools. Here we describe a systematic investigation of site‐specific labeling of pre‐miRNAs to identify positions for the incorporation of functional groups, in order not to hinder their processing into active mature miRNAs.  相似文献   
78.
Biodegradable poly(ε‐caprolactone‐co‐δ‐valerolactone) copolymers were synthesized and investigated to study their behavior in aqueous medium. The copolyesters were produced by ring opening polymerization between ε‐caprolactone (CL) and δ‐valerolactone (VL) in bulk at 140°C using tin(II) octoate as catalyst. They were characterized by using 1H NMR, size exclusion chromatography, differential scanning calorimetry, and MALDI TOF mass spectrometry. Reactivity ratio determination gave an insight on their microstructure. Hydration, hydrolytic degradation, and biocide release of P(CL‐VL) films with different molecular weights values were studied. A one‐order kinetic whose rate constant decreases with copolymer macromolecular weight was observed. Although the molecular weight decrease remained relatively weak after 8 months of immersion, a correlation between molecular weight and hydrolysis rate was shown by high performance liquid chromatography‐mass spectrometry. The ability of the P(CL‐VL) films to release active compounds dispersed in the films was studied by atomic absorption spectroscopy. The release behavior of all copolymers was identical with a zero‐order kinetic. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43007.  相似文献   
79.
Although the viable but not culturable (VBNC) state has been studied in detail in bacteria, it has been suggested that maintenance of viability with loss of culturability also exists in eukaryotic cells, such as in the wine spoilage yeast Brettanomyces. To provide conclusive evidence for the existence of a VBNC state in this yeast, we investigated its capacity to become viable and nonculturable after sulfite stress, and its ability to recover culturability after stressor removal. Sulfite addition induced loss of culturability but maintenance of viability. Increasing the medium pH to decrease the concentration of toxic SO(2) allowed yeast cells to become culturable again, thus demonstrating the occurrence of a VBNC state in Brettanomyces upon SO(2) exposure. Relative to culturable Brettanomyces, VBNC yeast cells were found to display a 22% decrease in size on the basis of laser granulometry. Assays for 4-ethylguaiacol and 4-ethylphenol, volatile phenols produced by Brettanomyces, indicated that spoilage compound production could persist in VBNC cells. These morphological and physiological changes in VBNC Brettanomyces were coupled to extensive protein pattern modifications, as inferred by comparative two-dimensional electrophoresis and mass spectrometric analyses. Upon identification of 53 proteins out of the 168 spots whose abundance was significantly modified in treated cells relative to control, we propose that the SO(2)-induced VBNC state in Brettanomyces is characterized by a reduced glycolytic flux coupled to changes in redox homeostatis/protein turnover-related processes. This study points out the existence of common mechanisms between yeast and bacteria upon entry to the VBNC state.  相似文献   
80.
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