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841.
Naima Ghalmi Marie Malice Jean-Marie Jacquemin Sidi-Mohamed Ounane Leila Mekliche Jean-Pierre Baudoin 《Genetic Resources and Crop Evolution》2010,57(3):371-386
Twenty landraces of cowpea (Vigna unguiculata (L.) Walp.) scattered throughout Algeria were compared through morphological and genetic characterization. At the morphological
level, for qualitative characters there was no intra-landrace variation and for quantitative characters the variations were
low except for landrace NAG2 Three different cultigroups were located in Algeria: Biflora that was dominant in the Sahara,
Melanophtalmus in the North and Unguiculata including one landrace in Kabylia and two in Sahara. The AMOVA analysis indicated
that the genetic variation was lower within than among agro-ecological regions. A Mantel test, revealed a correlation between
the qualitative morphological data and the geographical data (R = 0.28; P < 0.01), indicating that the degree of morphological change among landraces was roughly proportional to the geographical
distances separating them. Genetic diversity was analyzed by using 11 random amplified polymorphic DNA (RAPD) and 12 inter-simple
sequence repeat (ISSR) markers. No intra-landrace variability was found. The eleven RAPD primers yielded 77 bands, of which
45 (58.44%) were polymorphic; the genetic similarity ranged from 66.0 to 96.7%. The twelve ISSR primers provided a total of
104 bands, of which 65 (62.5%) were polymorphic; the genetic similarity ranged from 62.8 to 97.8%. cluster analysis showed
a good match between genetic background and geographical distribution, which was confirmed by the results of the Mantel test.
In particular, geographical data and genetic data were found to be correlated: (R = 0.33; P < 0.01) for RAPD, (R = 0.37; P < 0.01) for ISSR, and (R = 0.33; P < 0.01) for a combined RAPD-ISSR dataset. Moreover, despite the absence of significant correlation between morphological
and RAPD data (R = 0.14; P = 0.14), significant correlations between morphological data and both ISSR (R = 0.27, P < 0.05) and a combined RAPD-ISSR dataset (R = 0.22, P < 0.05) were noted. ISSR markers were better linked to morphological variation than were RAPD markers. However, despite this,
genetic distances among these landraces were found to be essentially the same no matter which markers were used. 相似文献
842.
Amy Marie Patrin Oen Magnus Sparrevik David N. Barton Udaya Sekhar Nagothu Gerald Jan Ellen Gijs D. Breedveld Jens Skei Adriaan Slob 《Journal of Soils and Sediments》2010,10(2):202-208
Introduction
Management options for large-scale contaminated sediment remediation projects can be challenging with regard to competing stakeholder interests. This has become apparent during the Oslofjord sediment remediation project (2005–2009) which caused considerable public discussion.Background
To learn from this project, the ‘Sediment and society’ project was initiated to develop a collaborative approach that will incorporate local and scientific knowledge in order to achieve mutual gains, win-win outcomes for the stakeholders, in the management of contaminated marine sediments.Method development
The project focuses on two Norwegian harbours: Oslo Harbour and Bergen Harbour. The Oslo Harbour case has been analysed ex-post, using elements of risk governance: participation, communication, information/knowledge and risk perception. The Bergen Harbour case is focused on the establishment of a citizens' jury as well as a stakeholder panel in Bergen Harbour.Preliminary results and observations
Thus far, the results suggest three important commonalities or challenges for stakeholder involvement: (1) how to include people who have important management information and local knowledge, but not much influence in the decision-making process; (2) how to secure resources to ensure participation and (3) how to engage and motivate stakeholders to participate early in the sediment remediation planning process. 相似文献843.
Ethyl formate and ethanol in air, eg in fumigant studies, were readily detected by gas chromatography (GC) (flame ionisation). Residues in wheat, barley and sultanas were analysed by GC, after extraction in polar solvents (eg methanol, aqueous propanol). Both natural levels and levels resulting from fumigation with ethyl formate were measured. Formic acid was extracted from commodities with polar solvents (eg methanol, water) and analysed by GC after esterification. Solvent extracts of commodities were concentrated after addition of disodium hydrogen orthophosphate, and an aliquot added to acidified alcohols (several combinations of acids and alcohols were tested) in a sealed container. Formic acid esters were determined by GC, from headspace sampling over the esterification solvent. Esterification was faster with strong acids than with boric acid. However, esterification with boric acid/butanol gave the least interference of all tested methods. Product identity was confirmed by GC/mass spectrometry. High natural levels of formic acid, and low natural levels of ethyl formate and ethanol, presented problems in identifying residues arising from fumigation. These natural levels are relevant to food regulations for ethyl formate, especially those based on ‘total formic acid, free and combined’. Polar columns (eg FFAP, carbowax) were useful for measurement of formic acid esters, which eluted before the alcohols used for esterification or extraction, whereas elution followed the molecular mass on non-polar columns, such as GS-Q or DB-624. © 1999 Society of Chemical Industry 相似文献
844.
Aluminum concentrations were measured in surface waters, pore waters and surface peats of 15 wetlands in south-central Ontario. Wetlands were grouped floristically and chemically as mineralpoor, moderately-poor or mineral-rich fen. Mineral-poor fens were dominated bySphagnum, were low in alkalinity (0.31μeq L?1) and pH (4.5–6.3). Moderately-poor fens had a mixture of vegetation (Sphagnum, sedges and grasses), mid-alkalinity (23–91μeq L?1) and pH (5.8–6.4). Mineral-rich fens were dominated by sedges and grasses, had high alkalinity (104–181μeq L?1) and circumneutral pH (6.2–6.3). Surface water Al concentrations were less in mineral-poor versus moderately-poor and mineral-rich fens (F=32.0; P<0.05). Pore water Al concentrations were lower in 4 of 5 mineral versus the mineral-rich fens (F=92.15; P<0.05). In all but two cases pore water Al (all species <0.2μm) were greater within the fen peats versus the overlying surface waters suggesting that peats could act as a source of Al to the overlying waters. In all wetlands, 70 and 30% of peat Al was recovered by a hydroxylamine hydrochloride/acetic extract (primarily inroganic) and an ammonium hydroxide extract (primarily organic), respectively. Differences in “extractable” Al recovered by the two reagents (i.e., inorganic+organic Al) among the 15 wetlands were independent of wetland type. Distribution coefficients, k d , were different among the 3 types of wetlands (F=25.0; P<0.05) with theSphagnum dominated mineral-poor fens containing higher values versus the sedge and grass dominated mineral-rich fens. Lower surface and pore water concentrations of Al in mineralpoor versus mineral-rich fens may in part be a result of differences in the degree of minerotrophic influences between the two types of peatlands. As well, the greater binding capacity ofSphagnum peat as indicated by higher k d 's in the mineral-poor fens, may have contributed to the observed lower pore water and surface water Al concentrations in mineral-poor versus mineral-rich fens. It has been postulated that anthropogenic acidification of peatlands will accelerate the transformation of a mineral-rich fen to that of a mineral-poor fen and ultimately to bog. Changes in Al geochemistry that may ensue as this transition occurs include decreases in pore and surface water Al concentrations with concurrent increases in peat bound Al. 相似文献
845.
In 1935, Bienenstock and coworkers claimed the presence of gluten-like material in the germ of the carob seed. The viscoelastic properties of the water-insoluble proteins isolated from carob germ, which we propose to call caroubin, have been confirmed by dynamic (G′ and G″) and static rheological measurements (texture profile analysis, viscoelastogram). Biochemical analyses showed important similarities (high glutamic acid content, size-exclusion HPLC profile, PAGE patterns of reduced and unreduced proteins) as well as large differences (high arginine and low cysteine and proline content of caroubin, carbohydrate composition) between caroubin and wheat gluten. Besides potential new industrial uses of carob seed, caroubin could be a valuable material to help us understand the physicochemical basis of the viscoelastic properties of plant protein complexes like wheat gluten. 相似文献
846.
Marie‐France Dignac Ingrid Kgel‐Knabner Kerstin Michel Egbert Matzner Heike Knicker 《植物养料与土壤学杂志》2002,165(3):281-289
Due to high nitrogen deposition in central Europe, the C : N ratio of litter and the forest floor has narrowed in the past. This may cause changes in the chemical composition of the soil organic matter. Here we investigate the composition of organic matter in Oh and A horizons of 15 Norway spruce soils with a wide range of C : N ratios. Samples are analyzed with solid‐state 13C nuclear magnetic resonance (NMR) spectroscopy, along with chemolytic analyses of lignin, polysaccharides, and amino acid‐N. The data are investigated for functional relationships between C, N contents and C : N ratios by structural analysis. With increasing N content, the concentration of lignin decreases in the Oh horizons, but increases in the A horizons. A negative effect of N on lignin degradation is observed in the mineral soil, but not in the humus layer. In the A horizons non‐phenolic aromatic C compounds accumulate, especially at low N values. At high N levels, N is preferentially incorporated into the amino acid fraction and only to a smaller extent into the non‐hydrolyzable N fraction. High total N concentrations are associated with a higher relative contribution of organic matter of microbial origin. 相似文献
847.
Greiner R Larsson Alminger M Carlsson NG Muzquiz M Burbano C Cuadrado C Pedrosa MM Goyoaga C 《Journal of agricultural and food chemistry》2002,50(23):6865-6870
Using a combination of high-performance ion chromatography analysis and kinetic studies, the pathway of dephosphorylation of myo-inositol hexakisphosphate by the phytases purified from faba bean and lupine seeds, respectively, was established. The data demonstrate that the legume seed phytases under investigation dephosphorylate myo-inositol hexakisphosphate in a stereospecific way. The phytase from faba bean seeds and the phytase LP2 from lupine seeds degrade phytate by sequential removal of phosphate groups via D-Ins(1,2,3,5,6)P(5), D-Ins(1,2,5,6)P(4), D-Ins(1,2,6)P(3), and D-Ins(1,2)P(2) to finally Ins(2)P, whereas the phytases LP11 and LP12 from lupine seeds generate the final degradation product Ins(2)P via D-Ins(1,2,4,5,6)P(5), D-Ins(1,2,5,6)P(4), D-Ins(1,2,6)P(3), and D-Ins(1,2)P(2). 相似文献
848.
Olsson ME Andersson CS Oredsson S Berglund RH Gustavsson KE 《Journal of agricultural and food chemistry》2006,54(4):1248-1255
The effects of extracts from five cultivars of strawberries on the proliferation of colon cancer cells HT29 and breast cancer cells MCF-7 were investigated, and possible correlations with the levels of several antioxidants were analyzed. In addition, the effects of organic cultivation compared to conventional cultivation on the content of antioxidants in the strawberries and strawberry extracts on the cancer cell proliferation were investigated. The ratio of ascorbate to dehydroascorbate was significantly higher in the organically cultivated strawberries. The strawberry extracts decreased the proliferation of both HT29 cells and MCF-7 cells in a dose-dependent way. The inhibitory effect for the highest concentration of the extracts was in the range of 41-63% (average 53%) inhibition compared to controls for the HT29 cells and 26-56% (average 43%) for MCF-7 cells. The extracts from organically grown strawberries had a higher antiproliferative activity for both cell types at the highest concentration than the conventionally grown, and this might indicate a higher content of secondary metabolites with anticarcinogenic properties in the organically grown strawberries. For HT29 cells, there was a negative correlation at the highest extract concentration between the content of ascorbate or vitamin C and cancer cell proliferation, whereas for MCF-7 cells, a high ratio of ascorbate to dehydroascorbate correlated with a higher inhibition of cell proliferation at the second highest concentration. The significance of the effect of ascorbate on cancer cell proliferation might lie in a synergistic action with other compounds. 相似文献
849.
Entomopathogenic nematodes (EPN) in the families Steinernematidae and Heterorhabditidae occur naturally in the soil and are produced commercially for the management of soil-dwelling pests. EPN infected cadavers also represent a potential resource for other soil organisms. We examined the short-term (24 h) response in abundance, diversity and community composition of localized soil microinvertebrates to the presence of EPN-infected insect cadavers in no-till and conventional-till maize. We hypothesized that the response of soil microinvertebrates to the EPN-infected cadavers would vary by soil management practices and EPN species. We expected to observe greater numbers and diversity of arthropods in no-till compared with conventional-till soil, and in the vicinity of steinernematid-infected insect cadavers compare to what would be found in the vicinity of heterorhabditid-infected cadavers. 45,606 invertebrates were collected and identified to 134 morphotaxa. Tillage regime accounted for the majority of the variation observed (84.6%), whereas nematode treatment accounted for 7.5%. Taxonomic richness of invertebrates was greater in treatments with Steinernema carpocapsae-infected cadavers than with Heterorhabditis bacteriophora-infected cadavers. Some invertebrates increased in abundance where EPN were applied whereas others decreased, regardless of tillage practice. Applications of Galleria cadavers infected with steinernematids elicited positive responses from two mite taxa, Galumnidae and Scheloribates spp., while negative responses were elicited from three mite (Histiostomatidae, Scheloribates spp., Eupodes spp.), taxa and Entomobryidae (Collembola) in response to applications of Heterorhabditis-infected cadavers. 相似文献
850.
Pruyne D Evangelista M Yang C Bi E Zigmond S Bretscher A Boone C 《Science (New York, N.Y.)》2002,297(5581):612-615
Nucleation of branched actin filaments by the Arp2/3 complex is a conserved process in eukaryotic cells, yet the source of unbranched actin filaments has remained obscure. In yeast, formins stimulate assembly of actin cables independently of Arp2/3. Here, the conserved core of formin homology domains 1 and 2 of Bni1p (Bni1pFH1FH2) was found to nucleate unbranched actin filaments in vitro. Bni1pFH2 provided the minimal region sufficient for nucleation. Unique among actin nucleators, Bni1pFH1FH2 remained associated with the growing barbed ends of filaments. This combination of properties suggests a direct role for formins in regulating nucleation and polarization of unbranched filamentous actin structures. 相似文献