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31.
José Antonio Curiel Rossana Coda Antonio Limitone Kati Katina Mari Raulio Giammaria Giuliani Carlo Giuseppe Rizzello Marco Gobbetti 《Journal of Cereal Science》2014
Wheat flour, which was rendered gluten-free by sourdough lactic acid bacteria fermentation and fungal proteases, was used for manufacturing experimental gluten-free pasta (E-GFp), according to a traditional process with low temperature drying cycle. Chemical, technological, structural, nutritional and sensory features were characterized and compared with those of commercial gluten-free (C-GFp) and durum wheat pasta (C-DWp). As shown through immunological analyses, the residual concentration of gluten of the hydrolyzed wheat flour was below 10 ppm. E-GFp showed rapid water uptake and shorter optimal cooking time compared to the other pastas. Despite the absence of the gluten network, the supplementation with pre-gelatinized rice flour allowed structural properties of E-GFp, which were comparable to those of C-GFp. The in vitro protein digestibility of E-GFp resulted the highest. Probably due to proteolysis during sourdough fermentation; chemical scores, essential amino acid profile, biological value and nutritional index of E-GFp were higher than those of C-DWp. The hydrolysis index (HI) of E-GFp was ca. 30% lower than that found for C-GFp. As shown by sensory analysis, the characteristic of E-GFp were acceptable. The manufacture of E-GFp should be promising to expand the choice of gluten-free foods, which combine sensory and nutritional properties. 相似文献
32.
Daniela Bertotto Carlo Poltronieri Elena Negrato Duilio Majolini Giuseppe Radaelli Claudia Simontacchi 《Aquaculture Research》2010,41(8):1261-1267
Plasma cortisol is the most commonly used indicator of stress in fish but, as the blood sampling procedure itself can be a source of stress, it would be helpful to measure cortisol using less invasive matrices. It is also necessary to find alternative matrices as stress indicators in dead fish in which blood sampling is impossible. In the present study, we investigated transport stress in three aquaculture species, European sea bass (Dicentrarchus labrax L.), common carp (Cyprinus carpio L.) and rainbow trout (Oncorhynchus mykiss Walbaum), by cortisol determination (radioimmunoassay) in plasma and other matrices (skin mucus, gut content, lateral muscle and caudal fin). Cortisol significantly increased after transport in all species and matrices, except in the sea bass gut content, where it remained unchanged. The three species responded to transport stress by producing different cortisol levels. In conclusion, the significant correlation found between plasma cortisol and most of the other matrices opens up the possibility of using them to evaluate stress in fish: mucus sampling is a less invasive method than blood sampling, and in addition to muscle and fin sampling, it can be used in postmortem fish. 相似文献
33.
Massimo Iovino Mirko Castellini Vincenzo Bagarello Giuseppe Giordano 《Land Degradation \u0026amp; Development》2016,27(2):200-210
Both capacitive indicators derived from the water retention curve and dynamic measurements of the flow‐weighted mean pore radius, R0, were used to assess the soil physical quality of two agricultural areas (cropland and olive orchard) and two natural areas (grassland and managed woodlot plantation) potentially subject to soil degradation. The overall idea of the study was to investigate whether a dynamic indicator quantitatively derived from hydraulic conductivity measurements could be used to supplement the traditionally applied capacitive indicators retrieved from water retention measurements. According to the available criteria, only the surface layer of the cropland site showed optimal soil physical quality. In the grassland and woodlot sites, the physical quality was deteriorated also as a consequence of compaction because of grazing. Overall, the physical quality was better in tilled than nontilled soils. The optimal soil in terms of capacitive indicators had hydraulic conductivity close to saturation that was intermediate among the different land uses, and it remained 1·3–1·9 times higher than that observed in the natural sites even when the largest pores emptied. A depth effect on R0 was observed only when larger macropores were activated. It was suggested that water transmission parameters are more affected by changes in large pore domain. The plant available water content and Dexter's S‐index showed inverse statistically significant regressions with R0. The empirical relationships were physically convincing given that, at increasing R0, the contribution of macropores increases, water is transmitted faster below the root zone and the soil's ability to store water is reduced. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
34.
Anthocyanin composition in berries of Rhamnus alaternus L., a perennial wild shrub typical of the Mediterranean area, was determined for the first time. The pigments were extracted from the berries with 0.1% HCl in methanol and purified using a C-18 solid-phase cartridge. High-performance liquid chromatography diode array detection-mass spectrometry analysis showed that delphinidin 3-O-rutinoside represented about 62.4% of the total pigments. Other anthocyanins were 3-O-rutinoside derivatives of cyanidin (8.4%), petunidin (15.8%), pelargonidin (4.7%), and peonidin and malvidin (8.7%). The concomitant presence of the six most common anthocyanidins suggested that R. alaternus berries, besides being a good pigment source, could also be a useful tool for anthocyanin identification. 相似文献
35.
36.
Vicentini CB Forlani G Manfrini M Romagnoli C Mares D 《Journal of agricultural and food chemistry》2002,50(17):4839-4845
Some pyrazolo[3,4-d]pyrimidin-4(5H)-thione, pyrazolo[3,4-d][1,3]thiazin-4-one/thione, and pyrazolo[1,5-c][1,3,5]thiadiazine-4-one/thione derivatives were synthesized and screened for antifungal activity against the causal agent of rice blast disease, Magnaporthe grisea. In all cases a remarkable inhibition of fungal growth was found in the range from 10 to 200 microg x mL(-1). Several compounds were able to control mycelium growth at a rate of 10 microg x mL(-1), a concentration at which the reference compound tricyclazole was completely ineffective. At least in the case of the most active substance, at the same dose the growth of seedlings or cultured cells of rice was substantially unaffected. Results allowed definition of structural requirements either to maintain or to enhance mycotoxic activity. 相似文献
37.
Changes in phenolic composition and antioxidant activity of virgin olive oil during frying 总被引:2,自引:0,他引:2
Gómez-Alonso S Fregapane G Salvador MD Gordon MH 《Journal of agricultural and food chemistry》2003,51(3):667-672
The concentration of hydroxytyrosol (3,4-DHPEA) and its secoiridoid derivatives (3,4-DHPEA-EDA and 3,4-DHPEA-EA) in virgin olive oil decreased rapidly when the oil was repeatedly used for preparing french fries in deep-fat frying operations. At the end of the first frying process (10 min at 180 degrees C), the concentration of the dihydroxyphenol components was reduced to 50-60% of the original value, and after six frying operations only about 10% of the initial components remained. However, tyrosol (p-HPEA) and its derivatives (p-HPEA-EDA and p-HPEA-EA) in the oil were much more stable during 12 frying operations. The reduction in their original concentration was much smaller than that for hydroxytyrosol and its derivatives and showed a roughly linear relationship with the number of frying operations. The antioxidant activity of the phenolic extract measured using the DPPH test rapidly diminished during the first six frying processes, from a total antioxidant activity higher than 740 micromol of Trolox/kg down to less than 250 micromol/kg. On the other hand, the concentration of polar compounds, oxidized triacylglycerol monomers (oxTGs), dimeric TGs, and polymerized TGs rapidly increased from the sixth frying operation onward, when the antioxidant activity of the phenolic extract was very low, and as a consequence the oil was much more susceptible to oxidation. The loss of antioxidant activity in the phenolic fraction due to deep-fat frying was confirmed by the storage oil and oil-in-water emulsions containing added extracts from olive oil used for 12 frying operations. 相似文献
38.
Assessing antioxidant and prooxidant activities of phenolic compounds 总被引:30,自引:0,他引:30
Methods for determining primary antioxidant activity were evaluated. A beta-carotene bleaching method and a free radical method using 2, 2-diphenyl-1-picrylhydrazyl (DPPH(*)) were modified to rapidly test samples for potential antioxidant activity. Malonaldehyde production in a linoleic acid emulsion system assayed by an HPLC method was also used to determine antioxidant and prooxidant activities initiated by a metal catalyst (Cu(2+)). All methods were used to assess activity of selected phenolic compounds including several anthocyanidins/anthocyanins and selected berry extracts. Most phenolic compounds had prooxidant activity at low concentrations, unlike synthetic antioxidants (BHA and BHT). Compounds with similar structures exhibited comparable trends in antioxidant activity. Antioxidant activity usually increased with an increase in the number of hydroxyl groups and a decrease in glycosylation. The antioxidant activity of many phenolic compounds and extracts was comparable to those of synthetic antioxidants using the beta-carotene bleaching and HPLC methods. 相似文献
39.
40.
Fluorescence spectroscopy of a green fluorescent protein mutant at single-molecule resolution has revealed a remarkable oscillatory behavior that can also be driven by applied fields. We show that immediately before unfolding, several periodic oscillations among the chemical substates of the protein chromophore occur. We also show that applied alternating electric or acoustic fields, when tuned to the protein characteristic frequencies, give rise to strong resonance effects. 相似文献