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101.
Bioguided isolation and identification of the nonvolatile antioxidant compounds from fennel (Foeniculum vulgare Mill.) waste 总被引:1,自引:0,他引:1
Parejo I Viladomat F Bastida J Schmeda-Hirschmann G Burillo J Codina C 《Journal of agricultural and food chemistry》2004,52(7):1890-1897
A bioguided isolation of an aqueous extract of fennel waste led to the isolation of 12 major phenolic compounds. Liquid chromatography coupled to atmospheric pressure chemical ionization mass spectrometry (LC/UV/APCI-MS) combined with spectroscopic methods (NMR) was used for compound identification. Radical scavenging activity was tested using three methods: DPPH*, superoxide nitro-blue tetrazolium hypoxanthine/xanthine oxidase, and *OH/luminol chemiluminescence. In addition to products described in the literature, eight antioxidant compounds were isolated and identified for the first time in fennel: 3-caffeoylquinic acid, 4-caffeoylquinic acid, 1,5-O-dicaffeoylquinic acid, rosmarinic acid, eriodictyol-7-O-rutinoside, quercetin-3-O-galactoside, kaempferol-3-O-rutinoside, and kaempferol-3-O-glucoside. The structures of eriodictyol-7-O-rutinoside and quercetin-3-O-glucuronide were completely elucidated by two-dimensional NMR experiments. The isolated compounds exhibited a strong antiradical scavenging activity, which may contribute to the interpretation of the pharmacological effects of fennel. 相似文献
102.
Janneth Jara-Samaniego Dolores Perez-Murcia Concepción Paredes Luis Gálvez-Sola Irene Gavilanes-Terán 《Communications in Soil Science and Plant Analysis》2015,46(4):157-169
In South America, a high percentage of urban waste streams are not well managed, implying associated health and environmental risks. In Ecuador, around 2.7 million tons of municipal solid wastes (MSW) are generated annually, with 80 percent located in urban areas. Correct management and hygienic and ecological issues from these increased quantities of waste is the responsibility of municipalities that must provide sewerage, wastewater treatment, and solid waste management, according to the Constitution of the Republic (Art 264). With only seven licensed landfill areas out of thirty-one in total (66 percent mechanized and 34 percent manually sorted), a sustainable waste management model must be developed to reduce environmental hazards and also to obtain new bioproducts such as compost or fertilizers. Agricultural utilization of MSW compost is the most cost-effective management option compared to traditional means such as landfilling or incineration, and this option also enables the recycling of potential plant nutrients. In this work, the problem we addressed was to obtain analytical information about representative MSW samples from different origins and locations within the Chimborazo region in order to establish its potential for composting. In the studied MSW samples (which included sludge from aerobic wastewater treatment plants), high nutrient contents and low concentrations of heavy metals were observed, showing great potential to develop high-quality compost. In addition, improvement of separate collections of food market and/or municipal gardening wastes can provide specific clean waste streams of degradable materials to be managed separately from not separately collected MSW. 相似文献
103.
Miranda-Fuentes P. Yousef-Yousef M. Valverde-García P. Rodríguez-Gómez Irene M. Garrido-Jurado I. Quesada-Moraga E. 《Journal of pest science》2021,94(3):933-945
Journal of Pest Science - The use of entomopathogenic fungi for pest control is gaining increasing attention. These fungi act as contact biological insecticides but also via endophytic colonization... 相似文献
104.
Millán-Leiva Anabel Marín Óscar De la Rúa Pilar Muñoz Irene Tsagkarakou Anastasia Eversol Heather Christmon Krisztina vanEngelsdorp Dennis González-Cabrera Joel 《Journal of pest science》2021,94(4):1505-1517
Journal of Pest Science - Managed honey bees have suffered severe seasonal losses for most of the past 30 years, while at the same time there is a growing need for food crop pollination.... 相似文献
105.
We determined the influence of environmental factors (air and soil temperature, precipitation, photoperiod) on onset of xylem growth in Scots pine (Pinus sylvestris L.) within a dry inner Alpine valley (750 m a.s.l., Tyrol, Austria) by repeatedly sampling micro-cores throughout 2007-10 at two sites (xeric and dry-mesic) at the start of the growing season. Temperature sums were calculated in degree-days (DD) ≥5 °C from 1 January and 20 March, i.e., spring equinox, to account for photoperiodic control of release from winter dormancy. Threshold temperatures at which xylogenesis had a 0.5 probability of being active were calculated by logistic regression. Onset of xylem growth, which was not significantly different between the xeric and dry-mesic sites, ranged from mid-April in 2007 to early May in 2008. Among most study years, statistically significant differences (P<0.05) in onset of xylem growth were detected. Mean air temperature sums calculated from 1 January until onset of xylem growth were 230 ± 44 DD (mean ± standard deviation) at the xeric site and 205 ± 36 DD at the dry-mesic site. Temperature sums calculated from spring equinox until onset of xylem growth showed somewhat less variability during the 4-year study period, amounting to 144 ± 10 and 137 ± 12 DD at the xeric and dry-mesic sites, respectively. At both sites, xylem growth was active when daily minimum, mean and maximum air temperatures were 5.3, 10.1 and 16.2 °C, respectively. Soil temperature thresholds and DD until onset of xylem growth differed significantly between sites, indicating minor importance of root-zone temperature for onset of xylem growth. Although spring precipitation is known to limit radial growth in P. sylvestris exposed to a dry inner Alpine climate, the results of this study revealed that (i) a daily minimum air temperature threshold for onset of xylem growth in the range 5-6 °C exists and (ii) air temperature sum rather than precipitation or soil temperature triggers start of xylem growth. Based on these findings, we suggest that drought stress forces P. sylvestris to draw upon water reserves in the stem for enlargement of first tracheids after cambial resumption in spring. 相似文献
106.
Ioannis V. Ganopoulos Konstantinos Kazantzis Ioannis Chatzicharisis Irene Karayiannis Athanasios S. Tsaftaris 《Euphytica》2011,181(2):237-251
It is important to couple phenotypic analysis with genetic diversity for germplasm conservation in gene bank collections.
The use of molecular markers supports the study of genetic marker-trait associations of biological and agronomic interest
on diverse genetic material. In this report, 19 Greek traditional sweet cherry cultivars and two international cultivars,
which were used as controls, were grown in Greece and characterized for 17 morpho-physiological traits, 15 simple sequence
repeat (SSR) loci and 10 inter simple sequence repeat (ISSR) markers. To our knowledge, this is the first report on molecular
genetic diversity studies in sweet cherry in Greece. Principal component analysis (PCA) of nine qualitative and eight quantitative
morphological parameters explain over 77.33% of total variability in the first five axes. The SSR markers yielded a combined
matching probability ratio (MPR) of 9.569 × e−12. The 15 SSR loci produced a total of 92 alleles. Ten ISSR primers generated
91 bands, with an average of 9.1 bands per primer. Expected heterozygosity (gene diversity) values of 15 SSR loci and 10 ISSR
markers averaged at 0.683 and 0.369, respectively. Based on stepwise multiple regression analysis (MRA), SSR alleles were
found associated with harvest time and fruit polar diameter. Furthermore, three ISSR markers were correlated with fruit harvest
and soluble solids and four ISSR markers were correlated with fruit skin color. Stepwise MRA identified six SSR alleles associated
with harvest time with a high correlation (P < 0.001), with linear associations with high F values. Hence, data analyzed by the use of MRA could be useful in marker-assisted breeding programs when no other genetic
information is available. 相似文献
107.
108.
Cost-effectiveness of groundwater conservation measures: A multi-level analysis with policy implications 总被引:1,自引:0,他引:1
Groundwater in Spain, as in other arid and semiarid countries worldwide, has been widely used in the expansion of irrigated agriculture. In the Spanish Mancha Occidental aquifer, the excessive, and sometimes illegal, water abstraction for irrigation has promoted outstanding socioeconomic development in the area, but it has also resulted in exploitation of the aquifer and degradation of valuable wetlands. Water policies implemented in the region have not yet managed to restore the aquifer and face strong social opposition. This paper uses a multi-scale modeling approach to explore the environmental and socio-economic impacts of alternative water conservation measures at the farm and basin levels. It also analyzes their comparative cost-effectiveness to help policy makers identify the least costly policy option for achieving the goal of the Mancha Occidental aquifer's sustainability. To conduct this analysis, a Mathematical Programming Model has been developed to simulate: the closing-up and taxed-legalization of unlicensed wells, uniform volumetric and block-rate water prices, water quotas, and water markets. Aggregate results show that net social costs are not substantially different across policy option, so none of the considered policy options will be clearly more cost-effective than the others. However, there are significant differences between private and public costs (at the farm and sub-basin levels), which will be critical for determining the application in practice of these policies. Results show that controlling illegal water mining (through the legalization of unlicensed wells) is necessary, but is not sufficient to recover the aquifer. Rather, effective water management in this area will require the implementation of other water management policies as well. Among them, uniform volumetric and block-rate water pricing policies will entail the lowest net social cost, but will produce important income losses in the smallest and most water-intensive farms, which might put at risk the viability of these farms and the social acceptance of the policies. Further investigations on social costs, policy enforcement capacity and public participation in water management are highly recommended. 相似文献
109.
Van Breedam W Costers S Vanhee M Gagnon CA Rodríguez-Gómez IM Geldhof M Verbeeck M Van Doorsselaere J Karniychuk U Nauwynck HJ 《Veterinary immunology and immunopathology》2011,141(3-4):246-257
The porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most important viral pathogens in the swine industry. Despite great efforts of pig holders, veterinarians, researchers and vaccine developers, the virus still causes major production losses. It is clear that efficient and correct monitoring and rational development of vaccines are crucial in the combat against this pathogen. PRRSV-specific monoclonal antibodies (mAbs) are essential tools for both diagnostic and research purposes. This study describes the production of PRRSV GP3-, GP5- and N-specific hybridomas and an extensive characterization of the mAbs. The N-specific mAbs generated in this study appear to be useful tools for diagnostics, as they were found to react with genetically very different PRRSV isolates and may serve to discriminate between European and American type PRRSV isolates. These mAbs also allowed detection of the PRRSV N protein in both formalin-fixed, paraffin-embedded tissue sections and frozen tissue sections of PRRSV-infected lungs, further illustrating their diagnostic value. Different neutralization assays pointed out that none of the GP3- and GP5-specific mAbs tested shows virus-neutralizing capacity. This is noteworthy, as these mAbs recognize epitopes in the predicted ectodomains of their target protein and since the GP5-specific antibodies specifically react with the antigenic region that corresponds to the "major neutralizing epitope" suggested for American type PRRSV. The current findings argue against an important role of the identified antigenic regions in direct antibody-mediated neutralization of European type PRRSV in vivo. However, it is also clear that findings concerning a specific PRRSV epitope cannot always be generalized, as the antigenic determinants and their biological properties may differ radically between different virus isolates. 相似文献
110.
Barranco I Gómez-Laguna J Rodríguez-Gómez IM Salguero FJ Pallarés FJ Bernabé A Carrasco L 《Veterinary immunology and immunopathology》2011,139(2-4):210-216
Apoptosis is a strictly regulated mechanism of cell death that involves a complex network of biochemical pathways. Whether a cell undergoes apoptosis or not depends on a delicate balance of anti- and pro-apoptotic stimuli. This phenomenon can be induced by two different pathways: intrinsic and extrinsic pathways. The main aim of this study was to determine the ideal fixative and antigen retrieval method in porcine paraffin embedded tissues for the immunohistochemical detection of apoptosis mediators, from both extrinsic and intrinsic pathways. Tonsil, retropharyngeal lymph node and lung tissue samples were fixed in 10% neutral buffered formalin, Bouin solution and zinc salts fixative (ZSF) and different unmasking methods were carried out. Both 10% neutral buffered formalin and ZSF resulted as the fixatives of election to study apoptosis phenomena. Tween 20 (0.01% in PBS), citrate buffer (microwave, pH 6.0) and/or protease type XIV were the antigen retrieval methods which displayed better labelling. Our results allow to deep in the knowledge of apoptosis and its role in the pathogenesis of porcine diseases. 相似文献