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131.
CLIP identifies Nova-regulated RNA networks in the brain 总被引:1,自引:0,他引:1
132.
Giovanni Di Matteo Irene Tunno Pierfrancesco Nardi Paolo De Angelis Giada Bertini Gianfranco Fabbio 《Annals of Forest Science》2014,71(8):885-895
Context
Harvesting of Mediterranean oak coppice forests has been progressively suspended on a share of cover over the last decades. Positive growth trend in outgrown coppices no longer harvested on short rotations now drives natural forest restoration on wide areas, and it represents a potential carbon sink in view of global warming.Aims
Our goals were to estimate carbon (C) and nitrogen (N) content per compartment in two deciduous oak outgrown coppice forests, aged differently and growing under unequal site quality, to verify whether C concentration across compartments is in agreement with the conventional conversion rate of 0.5.Methods
Ecosystem C and N pools were assessed by multiplying the whole coppice mass (combining specific allometric functions, root-to-shoot ratio, and soil sampling) by respective C and N concentrations.Results
The results point out that the largest percentage of N was stored in 15-cm topsoil (84.06 and 73.34 % at the younger and older site, respectively), whereas the proportion of organic ecosystem C pool was more variable, as a consequence of the amount and allocation of phytomass. We found that, in most cases, C concentration was less than the conventional conversion rate of 0.5, especially in deadwood, O layer, and root compartments.Conclusion
The findings provide further knowledge of C and N storage into these new built-up forest types and the evidence that a detailed analysis may get higher accuracy in the pools estimate, producing a more reliable outlook on dynamics and climate change mitigation ability of these systems. 相似文献133.
Matteo Rossanese DVM SPSA CertAVP MSc MRCVS Brandan Wustefeld-Janssens BSc BVSc CertAVP DECVS MRCVS Cleo Price BVSc MRCVS Ben Mielke BVSc MRCVS Samantha Woods BSc MA VetMB CertSAS DECVS FHEA MRCVS Nicola Kulendra BVetMed CertVDI DECVS MRCVS Guillaume Chanoit DEDV MSc PhD DACVS DECVS FHEA 《Veterinary surgery : VS》2020,49(4):659-667
134.
Stagnati Lorenzo Busconi Matteo Soffritti Giovanna Martino Michelangelo Lanubile Alessandra Marocco Adriano 《Genetic Resources and Crop Evolution》2021,68(7):2931-2942
Genetic Resources and Crop Evolution - Sorghum [Sorghum bicolor (L.) Moench] is a subsistence crop and the main food for populations in arid or semiarid regions and it is appreciated for the... 相似文献
135.
Giovanni Pratesi Matteo Zoppi Thomas Vaiani Francesca Calastrini 《Water, air, and soil pollution》2007,179(1-4):283-296
Morphometric and compositional studies have been performed on both PM10–2.5 and PM2.5 aerosol collected in the city of Prato, Italy. Chemical analysis has been carried out using PIXE technique and factor analysis was applied for the source apportionment process. Industrial emissions, vehicular traffic as well as crustal dust and marine aerosol were the sources identified. SEM-EDS analysis has been employed to individually characterize particles collected during a week of the sampling campaign. The morphometric study, performed on 43,671 particles, revealed that, for both the fine and coarse fraction, about 2/3 of particles display a high roundness coefficient, 1/3 of them a medium value, while only a small number of particles (from silicates and organics) exhibits a low roundness coefficient. Similarly, particles with small surface area represent the greater portion in both fractions. Particles classified as organics, metals and oxides, chlorides, carbonates, phosphates, sulphates and silicates have been detected in the PM10–2.5 while in the PM2.5 chlorides and phosphates are lacking. Silicates are about the same percentage, by concentration number, in the coarse and fine fraction (20.7% and 20.5% respectively) showing that this material, at least one fifth of the total PM, might be the result of crustal erosion and anthropic activities. The purpose of this work has been that of providing a contribution to the study of particulate matter and took an effort for relating morphometric and compositional features of urban aerosol collected in a medium size industrial city. 相似文献
136.
Differentiation of natural and synthetic phenylalanine and tyrosine through natural abundance 2H nuclear magnetic resonance 总被引:1,自引:0,他引:1
Brenna E Fronza G Fuganti C Pinciroli M 《Journal of agricultural and food chemistry》2003,51(17):4866-4872
The natural abundance deuterium NMR characterization of samples of the amino acids tyrosine (1) and phenylalanine (2), examined as the acetylated methyl esters 4 and 6, has been performed with the aim to identify by these means the contribution in animals of the hydroxylation of the diet l-phenylalanine (2) to the formation of l-tyrosine (1), a feature previously revealed on the same samples through the determination of the phenolic delta(18)O values. The study, which includes also the NMR examination of benzoic acid (5) from 2 and of tyrosol (7) from 1, substantially fails in providing the required information because the mode of deuterium labeling of tyrosine samples of different origins is quite similar but indicates a dramatic difference in the deuterium labeling pattern of the two amino acids 1 and 2. The most relevant variation is with regard to the deuterium enrichments at the CH(2) and CH positions, which are inverted in the two amino acids of natural derivation. Moreover, whereas the diastereotopic benzylic hydrogen atoms of l-tyrosine (1) appear to be equally deuterium enriched, in l-phenylalanine (2) the (D/H)(3)(R)() > (D/H)(3)(S)(). Similarly, benzoic acid (5) shows separate signals for the aromatic deuterium nuclei, which are quite indicative of the natural or synthetic derivation. The mode of deuterium labeling of the side chain of 1 and 2 is tentatively correlated to the different origins of the two amino acids, natural from animal sources for l-tyrosine and biotechnological probably from genetically modified microorganisms for l-phenylalanine. 相似文献
137.
Bonoli M Bendini A Cerretani L Lercker G Toschi TG 《Journal of agricultural and food chemistry》2004,52(23):7026-7032
Capillary electrophoresis (CE) can be effectively used as a fast screening tool to obtain qualitative and semiquantitative information about simple and complex phenolic compounds of extra virgin olive oil. Three simple phenols (tyrosol, hydroxytyrosol, and vanillic acid), a secoiridoid derivative (deacetoxy oleuropein aglycon), and two lignans (pinoresinol and acetoxypinoresinol) were detected as the main compounds in extra virgin olive oils by high-performance liquid chromatography (HPLC) and capillary zone electrophoresis (CZE). Spectrophotometric indices, radical scavenging activity, and oxidative stability of extra virgin olive oil samples obtained from olives hand-picked at different ripening degrees were statistically correlated with the CZE and HPLC quantification. The concentration of phenols in extra virgin olive oil decreased with ripeness of olive fruits. The high correlations found between CZE and the other analytical results indicate that CE can be applied as a rapid and reliable tool to routinely determine phenolic compounds in extra virgin olive oils. 相似文献
138.
Maria Agnese Sabatini Gloria Innocenti Matteo Montanari Sonia Ganassi 《Pedobiologia》2006,50(2):185-190
Effects of compost products, enriched or not-enriched with a strain of the mycoparasitic fungus Trichoderma atroviride, on the survival of the collembolan Protaphorura armata and the viability of fungal conidia after the transit through the springtail gut were investigated. The effect of compost enriched with Ca-Lignosulphonate (Ca-Ls), a low cost by-product of the acid sulphite pulping process, with lignin-like structure, on P. armata was also evaluated. All compost products enriched or not with the mycoparasitic fungus or Ca-Ls did not affect P. armata survival. No statistical differences were found in animal survival for different types of product or in enriched and not-enriched products. In addition to adults, live juveniles were also observed in all compost products. The gut content of animals, collected at the end of the survival test from compost enriched with T. atroviride, was examined under the light microscope, and in a few cases observations revealed the presence of some T. atroviride conidia. Subsequent tests carried out to study the viability of conidia after the transit through the springtail gut showed that colonies of the fungus developed from all faecal pellets produced by adult and juveniles specimens of P. armata previously fed on conidia of T. atroviride. These results suggest compatibility between Collembola and Trichoderma or Ca-Ls in the composts. 相似文献
139.
Rinaldo Botondi Matteo Vailati Andrea Bellincontro Riccardo Massantini Roberto Forniti Fabio Mencarelli 《Postharvest Biology and Technology》2009,51(1):97-103
Little is known about the biochemistry of the marron (Castanea sativa cv Marrone fiorentino) when it is soaked in water for the curing process; the immersion treatment time is still empirical and based on traditional knowledge. A study was carried out by keeping marrons in water for 7 d at 14 °C. Tap water and acid water (pH 3) were used in the following water/marron ratios 1:1, 1:2, and 3:2. After curing, the marrons were moved to air storage at room temperature (20 °C and 90% RH) for 1 week (shelf-life), and at 0 °C and 90% RH for 60 d. A large accumulation of carbon dioxide in the head space of the glass jar where the marrons were kept, was observed during water soaking, above all in samples in acid water with a water/marron ratio 1:2. In the first 5 d of water curing, a significant increase in acetaldehyde concentration and phenol content was measured in the marron pulp and subsequently, both compounds declined. Ethanol decreased slightly or remained constant. During the following week of shelf-life, the lowest respiration rate was measured in 1:1 and 1:2 samples while the highest rate was measured in acid water samples. SSC (solid soluble contents) increased in marrons soaked in acid water but remained constant under shelf-life conditions. SSC, ethanol, acetaldehyde and polyphenols did not change following storage at 0 °C for 2 months, but acid water samples showed a higher percentage of decayed marrons. Finally, it is possible to define some technological parameters. The immersion time of marrons in water must be at least 5 and no longer than 7 d, in order to avoid cell destruction. A water/marron ratio of 1:1 is advised. Using acid water, the samples with the ratios of 1:2 and 1:1 showed higher polyphenol and sugar contents. However, the metabolic response of these marrons was assumed to be a “stress response” to acid water. 相似文献
140.
Matteo Garbarino Emanuele Lingua Peter J. Weisberg Alessandra Bottero Fabio Meloni Renzo Motta 《Landscape Ecology》2013,28(5):805-817
European larch (Larix decidua Mill.) forests in the Alps are cultural landscapes that have been shaped by humans for centuries through traditional management. Biological and historical data sources were employed, and a multi-scale approach was adopted to capture the influence of factors affecting the structure of these forests. Landscape and stand scale dynamics were analyzed in four watersheds (c. 13,000 ha) of the western and central Italian Alps that have experienced different land-use intensities. Observed landscape changes were generalized using path analyses developed from a common conceptual model. Stand structure and a range of environmental variables were sampled in 203 circular plots, and land use and anthropogenic variables were derived from thematic maps and aerial photographs. We used multivariate statistical analyses (ordination and SEM models) to relate forest structure, anthropogenic influences, land uses, and topography. The most commonly observed land cover transition was an expansion of forests at the expense of open areas. All studied watersheds were dominated by larch forests, but their structure and spatial pattern differed greatly. Anthropogenic variables were less important at Ventina, the least accessible site, but emerged as fundamental to explain stand structure in the other study sites. Complexity of topography and proximity to roads had influenced past human activities mainly in the most accessible sites. Regeneration density was greatest at lower elevations and closer to human settlements. Quantification of the role played by forest harvesting and cattle grazing in past centuries is critical for understanding how global change factors may influence future dynamics of mountain forests in the European Alps and similar cultural landscapes worldwide. 相似文献