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71.
Angiogenesis is a fundamental process by which new blood vessels are formed. The angiogenesis process is induced by several growth factors. Among them angiogenin is the most potent blood vessel inducer known. In this paper, we have investigated the effect of green tea polyphenols, mainly the catechins, on an angiogenin-like protein induced angiogenesis process. The angiogenin-like protein was isolated from goat serum and the effect of green tea components was tested by the chicken chorioallantoic membrane (CAM) assay. The results show that green tea components are capable of reducing the vascularization on CAM that is induced by the angiogenin-like protein.  相似文献   
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73.
The present study investigates the chemical composition, anti-inflammatory, and antihypertensive activities, in vitro, from extracts of Cuphea lindmaniana and Cuphea urbaniana leaves. The extraction was performed ultrasound-assisted, and UHPLC/MS analysis was in positive mode ionization. The anti-inflammatory activity of the extracts and miquelianin were assayed at concentrations 0.001–10 μg/mL by chemotaxis on rat polymorphonuclear neutrophils. The antihypertensive activity was performed by angiotensin-converting enzyme (ACE) inhibition. From the nineteen proposed compounds, six of them are described for the first time in this genus. The extracts displayed antichemotactic effect with a reduction of 100 % of the neutrophil migration, in vitro, in most concentrations. The ACE-inhibition presented results ranging from 19.58 to 22.82 %. In conclusion, C. lindmaniana and C. urbaniana extracts contain a rich diversity of flavonoids and display in vitro anti-inflammatory and antihypertensive potential. Thus, this study could serve as a scientific baseline for further investigation, on developmental novel products with therapeutic actions.  相似文献   
74.
This research investigates an efficient dual valorization of olive mill wastewater in the biosynthesis of magnesium oxide nanoparticles and in the depollution of the effluent by Yarrowia lipolytica growth evaluation. After removal of polyphenols, the recovered biophenols were reacted with the magnesium precursor to provide magnesium oxide nanoparticles. In order to confirm the biosynthesized magnesium oxide nanoparticles, several analyses were undertaken. The Fourier transform infrared spectrum gives a broad absorption at 658 cm?1 confirming the presence of the magnesium oxide nanoparticles, while the UV/VIS absorption spectroscopy reveals an intense transition with a maximum absorption at 300 nm. The X‐ray diffraction and transmission electron microscopy analyses show that nanoparticles are in pure cubic crystalline with spherical and hexagonal shapes (average size is 19.4 nm). The zeta potential analysis illustrates a negative potential proving a good stability of the biosynthesized nanoparticles. Nanoparticles were assigned for their in vitro antibacterial activity against Escherichia coli, Enterobacter aerogenes, Salmonella typhimurium, Staphylococcus cohnii, and Bacillus niacini. The evaluation of the growth of Yarrowia lipolytica on the recovered olive mill wastewater after removal of polyphenols yielded 3.2 g/L of the Yarrowia biomass in 72 h without nutriment additions, providing an important decrease of chemical oxygen demand (73 %).  相似文献   
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This research was carried out to study phytochemical profile, in vitro antioxidant capacity, reducing power, anti‐hyperglycemic, anti‐inflammatory activities and simulated gastrointestinal digestion of 7‐day old cereal sprouts: spelt wheat ‘Nirvana’ (WSSpe), wheat ‘Simonida’ (WSSim), oat ‘Golozrni’ (OSG) and oat ‘Jadar’ (OSJ). OSG expressed significantly higher ( 0.05) total phenols (TPC) and flavonoids content (TFC), antioxidant capacities (DPPH and ABTS assays) and reducing power (EC50DPPH = 2.12 mg/ml; EC50ABTS = 0.87 mg/ml; EC0.5RP = 12.24 mg/ml) as well as anti‐hyperglycemic activity (EC50AHgA = 0.96 mg/ml). WSSpe had the highest content of chlorophyll (131.23 mg/100 g) and carotenoids (22.84 mg/100 g). WSSim possessed the most potent anti‐inflammatory activity (2.71 mg/ml), though not significantly different from OSG (2.77 mg/ml). The in vitro simulation of gastro‐intestinal digestion showed higher release of phenolic compounds in intestinal than in gastric fluid.  相似文献   
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Streptococcus mutans is a bacterium found in human oral biofilms (dental plaques) that is associated with the development of dental caries. Glucosyltransferases (GTFs) are key enzymes involved in dental plaque formation, and compounds that inhibit their activities may prevent dental caries. We developed a screening system for GTF-inhibitory activities, and used it to profile 44 types of herbal tea extracts. Lemon myrtle (Backhousia citriodora) extract exhibited the highest GTF-inhibitory activity, with an IC50 for GTF in solution of 0.14 mg mL?1. Furthermore, lemon myrtle extracts had the third-highest polyphenol content of all tested extracts, and strongly inhibited S. mutans biofilm. Interestingly, lemon myrtle extracts did not inhibit cell growth.  相似文献   
79.
During standardization of the methodology for estimating “cell-bound” alkaline phosphatase activity (APA: phosphomonoesterase) in Fucus spiralis L. (Phaeophyta), some of the nonphosphate moiety of the original phosphomonoester was found to be released to the medium subsequent to completion of the routine assays. This occurred with the two substrates generally employed in APA measurements: p-nitrophenyl phosphate (pNPP) and 4-methylumbelliferyl phosphate (MUP). Other marine macrophytes tested showed the same phenomenon. The conditions influencing retention were investigated to establish the simplest procedure for measuring APA. When using pNPP, the release of the product (p-nitrophenol) after the assays was maximum when assays were run for longer than 20 min and at slightly acid pH or at high pNPP concentrations. When using MUP, the leakage of the product (4-methylumbelliferone) after the assays was maximum when APA measurements were run for longer than 40 min and at neutral pH or at high MUP concentrations. The significance of the leakage of the nonphosphate moiety after APA assays is discussed.  相似文献   
80.
M. R. Davis 《Plant and Soil》1995,171(2):255-262
Interaction between soil acidity and vegetation phenolic concentration was investigated to identify mechanisms by which forests sustain productivity on extremely acidic, infertile soils. Contrasting soils on well-preserved marine terraces of the “Ecological Staircase’ near Mendocino, CA comprise an extreme edaphic gradient. Pygmy forests of dwarf (< 5m) Mendocino cypress (Cupressus pygmaea), Bolander pine (Pinus contorta var. bolanderi), and Bishop pine (Pinus muricata) are found on the oldest, most acidic soils, and along a gradient that includes three distinct levels of soil acidity, with pH(CaCl2) ranging from 5.0 to 3.0 in the upper mineral soil and from 4.0 to 2.0 in the litter layer where fine roots are concentrated. Mature foliage was collected from five sites on this edaphic gradient. Aqueous methanol extracts of the samples were analyzed for concentrations of total phenols and condensed tannin by the Prussian blue and acidified vanillin assays, respectively. There were significant differences (p<0.05) in foliar condensed tannin and phenolic concentrations within each species and concentrations were inversely related to soil pH, approximately doubling along the gradient. Natural selection for soil-regulated variation in polyphenol concentration is interpreted in the context of plant-litter-soil interactions as an adaptation that permits these conifers to survive in extremely acidic soils. H Lambers Section editor  相似文献   
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