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61.
Mineral deficiencies can seriously reduce crop yield and economic returns to farmers. Reflectance measurements may provide inexpensive and fast estimates of the mineral status of plants. This study was conducted to examine specific changes of leaf reflectance due to nutrient deficiencies. During the 1998 and 1999 growing seasons leaf scans of N‐, P‐, Mg‐, and Fe‐deficient corn plants were performed with a digital LEICA S1 PRO camera under controlled light conditions. Leaf scans were evaluated with the L*a*b*‐color system. This is a three‐dimensional system with parameter a* describing the green/red percentage and parameter b* the blue/yellow percentage of a color. L* represents the lightness of a color. The a* and b* parameters provided good prediction of N, P, Mg, and Fe status of the plants in the wavelength ranges of 380—390 nm, 430—780 nm, 516—780 nm, 516—IR, and 540—600 nm because reflectance changed specifically due to the nutrient deficiency. Analyses of water‐soluble and propanol‐soluble pigments showed no significant changes in absorbance during latent deficiency. The results indicate that reflectance measurements may provide a powerful tool for the specific detection of latent nutrient deficiencies in corn plants. 相似文献
62.
Claudio Caruso Andrea Gustinelli Paolo Pastorino Pier Luigi Acutis Riccardo Prato Loretta Masoero Simone Peletto Maria Letizia Fioravanti Marino Prearo 《Journal of fish diseases》2019,42(5):773-776
This work reports a mortality outbreak, occurred in 2015 and affecting juveniles of European perch (Perca fluviatilis L.) farmed in Italy. Perch rhabdovirus (PRV) was detected by viral isolation and biomolecular investigations. Phylogenetic analysis clustered our isolate into genogroup B, which also includes PRV isolates from Perca fluviatilis identified in France (2004–2009); diagnostic investigations also revealed opportunistic bacteria (Aeromonas hydrophila) and parasites (Chilodonella piscicola). Since, occasionally, PRV has been reported in the natural environment, which is often a source of eggs and broodstock for farms, it could be possible that both similar France and Italian isolate were imported from a same place elsewhere and have a common origin. Improving biosecurity measures (batch control) and disinfection of egg strings with an iodine‐based solution helps prevent apparent vertical transmission of PRV. 相似文献
63.
Pedohydrological properties were investigated on a piped slope in the Bergisches Land in the Rhenish Slate Mountains (Nordrhein‐Westfalen, Germany). The study confirmed that genesis and development of pipes decisively depend on hydrological conditions in the soils. Vertical water permeability of saturated samples was very high. This promoted fast seepage. Many macropores produced by earthworms also caused high transport capacity for soil water. Even more efficient were the burrows of moles and mice, enabling immediate infiltration and direct vertical and lateral water movement. On the contrary, the horizontal saturated permeability was low indicating no correlation with piping. Porosity of piped soils was not different to that of other soils of the region without pipes. 相似文献
64.
Federico Pallottino Marcello Biocca Pierfrancesco Nardi Simone Figorilli Paolo Menesatti Corrado Costa 《Precision Agriculture》2018,19(6):1011-1026
The relevance of precision agriculture produced a growth of the related literature over the years. However, a structured analysis of the published material is still missing. Thus, this study attempts to analyze the global scientific output of precision agriculture researches published during the period 2000–2016. By using a science mapping approach, mainly based on the application of network analysis tools, it was possible to investigate pivotal aspects of this research field such as publication trends, research topics and their geographical distribution. Using the Scopus database 17,756 scientific publications were retrieved from the chosen period. The number of publications increased after 2006, highlighting the vibrancy of the field. By authoring 35% of the publications, U.S.A. and China were the most active knowledge producer countries. Moreover, the generation of time resolved maps allowed us to identify agriculture engineering, computer science and agriculture studies as three main research areas characterizing precision agriculture panorama. The paper discusses the distribution of these topics at global level, among European countries and in Italy. Overall, this analysis represents the first holistic view of precision agriculture research providing valuable information for farmers, policy makers and researchers. 相似文献
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Vincenzo Alterio Emma Langella Giuseppina De Simone Simona Maria Monti 《Marine drugs》2015,13(4):1688-1697
The Carbon Concentration Mechanism (CCM) allows phytoplakton species to accumulate the dissolved inorganic carbon (DIC) necessary for an efficient photosynthesis even under carbon dioxide limitation. In this mechanism of primary importance for diatoms, a key role is played by carbonic anhydrase (CA) enzymes which catalyze the reversible hydration of CO2, thus taking part in the acquisition of inorganic carbon for photosynthesis. A novel CA, named CDCA1, has been recently discovered in the marine diatom Thalassiosira weissflogii. CDCA1 is a cambialistic enzyme since it naturally uses Cd2+ as catalytic metal ion, but if necessary can spontaneously exchange Cd2+ to Zn2+. Here, the biochemical and structural features of CDCA1 enzyme will be presented together with its putative biotechnological applications for the detection of metal ions in seawaters. 相似文献
68.
Chiara Nobili Simone D’Angeli Maria Maddalena Altamura Valeria Scala Anna Adele Fabbri Massimo Reverberi Corrado Fanelli 《European journal of plant pathology / European Foundation for Plant Pathology》2014,139(2):423-438
Wheat germinating caryopses may represent a starting point for the Fusarium Head Blight disease; however, only few studies concern the defence repertoire of wheat caryopses against fungal challenge. The germinating caryopses of two wheat commercial varieties (Blasco and Sagittario), differentially susceptible to FHB in the field, were inoculated with F. graminearum and the redox status in the interaction milieu, oxylipin production, the expression profile of some host-defence related genes, and programmed cell death in the aleuronic layer, were analysed. In Sagittario, the redox balance was profoundly modified and 9-oxylipins accumulated during fungal contamination. In this variety, F. graminearum produced a high quantity of deoxynivalenol whilst programmed cell death, also through metacaspases activation, was enhanced in the aleuronic layer of its caryopses. In Blasco, the expression of tolerance factors such as Pathogenesis-Related-protein1, glucosyl-transferase and glutathione transferase genes was up-regulated consequent to infection. Results show that unscavenged ROS and 9-oxylipins may be related to deoxynivalenol accumulation in the germinating caryopses of wheat after F. graminearum infection. 相似文献
69.
Edyta Wojciechowska Christoph H. Weinert Björn Egert Bernhard Trierweiler Markus Schmidt-Heydt Bernd Horneburg Simone Graeff-Hönninger Sabine E. Kulling Rolf Geisen 《European journal of plant pathology / European Foundation for Plant Pathology》2014,139(4):735-747
Tomato fruits can be contaminated by saprophytic strains of Alternaria alternata which is the reason for the frequent occurrence of Alternaria toxins like alternariol, alternariol monomethylether or tenuazonic acid in these types of products. It was shown earlier that alternariol is a colonization factor for tomatoes. In the current analysis two different tomato genotypes were analysed by untargeted comprehensive two-dimensional gas chromatography mass spectrometry (GC×GC-MS). This analysis revealed clear differences in the metabolic profiles which were paralleled by differences in resistance towards Alternaria colonization. One of the genotypes was more resistant against A. alternata infection and contained high amounts of chlorogenic acid in contrast to the other genotype which was sensitive against infection. In in vitro analysis, chlorogenic acid reduced alternariol biosynthesis during the first days of growth of A. alternata. Expression analysis of the alternariol polyketide synthase gene, a key gene in the biosynthesis of alternariol, also revealed a temporal reduction in its expression in the first phases of growth. However by chromatographic analysis it could be demonstrated that chlorogenic acid was degraded over time. This degradation leads to a relief of inhibition resulting in an only temporal inhibition of alternariol biosynthesis. In vivo colonization experiments revealed that chlorogenic acid reduces colonization of tomatoes by A. alternata in a concentration dependent manner, which however is partly counteracted by the addition of alterariol. 相似文献
70.
Saulo da Luz e Silva Paulo Roberto Leme Soraia Marques Putrino Anglica Simone Cravo Pereira Amaury Camilo Valinote Jos Carlos Machado Nogueira Filho Dante Pazzanese Duarte Lanna 《Livestock Science》2009,122(2-3):290-295
The purpose of this work was to evaluate the fatty acid composition of the Longissimus muscle from carcasses of Nellore steers fed diets with calcium salts of fatty acids (CSFA) and high moisture corn. Forty eight steers were fed during 70 days four diets containing dry corn (DC), high moisture corn (HM), dry corn plus CSFA (DC-CSFA) or high moisture corn plus CSFA (HM-CSFA). Fatty acid composition of the Longissimus muscle was determined by gas chromatography. Corn type had no effect on the ether extract percentage and in the content of the majority of the fatty acids, although steers fed HMC showed higher levels of polyunsaturated fatty acids and polyunsaturated/saturated ratio. Feeding CSFA increased ether extract percentage but had no effect on total of saturated, unsaturated and saturated: unsaturated ratio. Both high moisture corn and calcium salts of fatty acids increased CLA (cis9, trans11) and total CLA concentrations in intramuscular fat. 相似文献