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121.
José A. Orden Ricardo De la Fuente María Yuste Susana Martínez-Pulgarín José A. Ruiz-Santa-Quiteria Pilar Horcajo Antonio Contreras Antonio Sánchez Juan C. Corrales Gustavo Domínguez-Bernal 《Canadian journal of veterinary research》2010,74(1):54-58
The presence of antibodies to the intimin β-binding region (Int280-β) of attaching and effacing Escherichia coli (AEEC) in serum from 20 goat kids from 2 herds, as well as in goat colostrum, was investigated by enzyme-linked immunosorbent assay. In addition, the onset and subsequent pattern of shedding of AEEC from the same goat kids over a 6-mo period was investigated. All the colostrum and serum samples tested contained antibodies against Int280-β. The association between the antibody titer and the isolation of AEEC suggests that antibodies to intimin β do not prevent colonization of the intestine by AEEC in goat kids. The AEEC were generally shed only transiently. Most AEEC isolated from the kids belonged to serogroup O26. Three isolates belonged to serogroup O157. These data show that goat kids may be a reservoir of AEEC that are potentially pathogenic for humans. 相似文献
122.
Luciano Fernandes Sousa Rogério Martins Maurício Guilherme Rocha Moreira Lúcio Carlos Gonçalves Iran Borges Luiz Gustavo Ribeiro Pereira 《Agroforestry Systems》2010,79(2):189-199
This study aimed at evaluating the influence of a silvopastoral system (SPS) composed of “Aroeira” trees (Myracrodruon urundeuva) on the nutritional value of Brachiaria brizantha cv. Marandu forage grass over the rainy season. The experiment was conducted in the SPS located in the “Cerrado” biome in
Lagoa Santa County, Minas Gerais state, Brazil, in the agricultural year of 2004–2005. It was evaluated the influence of “Aroeira”,
whose density in the area was 140 trees/ha, on the following parameters of the B. brizantha cv. Marandu forage grass: forage mass harvest above stubble height, morphogenic attributes, bromatological composition and
nutritional value. The effects of “Aroeira” trees on the micro-climatic conditions were also evaluated. The experiment adopted
a randomized block design with five blocks (cutting seasons), two treatments (a shaded pasture—B. brizantha cv. Marandu shaded by M. urundeuva—and a pasture in full sun—B. brizantha cv. Marandu in full sun), and three replicates. The tree component, composed of the tree species M. urundeuva in the experimental density adopted, increased dry matter and crude protein of the forage mass harvest above stubble height,
without affecting the concentration of neutral detergent fibre or acid detergent fibre, thus causing dry matter and organic
matter in vitro degradability as well as effective degradability of the forage grass to remain the same as those obtained
in full sun. Therefore, the results of this study show the possibility of using trees and grass to increase both animal production
and environmental services. 相似文献
123.
J. S. Baggio F. P. Gonçalves S. A. Lourenço F. A. O. Tanaka S. F. Pascholati L. Amorim 《Plant pathology》2016,65(4):633-642
Rhizopus rot, caused by Rhizopus stolonifer, is a major postharvest disease of stone fruits. The disease is related to the occurrence of mechanical and physical damage; however, observations at a Brazilian wholesale market suggest that direct penetration can occur. Therefore, the penetration mechanisms of R. stolonifer in stone fruits were evaluated. To identify the production of enzymes that help with direct penetration by the pathogen, esterase activity, both in mycelial discs and in spore suspensions of the fungus in water and in modified Van Etten nutrient solution, was measured. Assays were also conducted to evaluate the growth of R. stolonifer on glucose or cutin as a sole carbon source. The pathogen grew on both media, and higher esterase activity was observed in the cutin medium. Wounded and unwounded peaches and nectarines were inoculated with R. stolonifer spore suspensions in water or in modified Van Etten nutrient solution. Wounded fruit inoculated with either of the R. stolonifer spore suspensions developed rhizopus rot, whereas unwounded fruit developed the rot only in the presence of spores in the modified Van Etten nutrient solution. Scanning electron and light microscopic examination showed the fungus can directly penetrate the nectarine cuticle. Diisopropyl fluorophosphate, a serine hydrolase inhibitor, prevented rot development in peaches. The results provide valuable evidence for the ability of R. stolonifer to directly penetrate unwounded stone fruits, probably due to the production of esterase enzymes. 相似文献
124.
Soil pollution by nonylphenol and nonylphenol ethoxylates and their effects to plants and invertebrates 总被引:1,自引:1,他引:0
Xavier Domene Wilson Ramírez Laura Solà Josep M. Alcañiz Pilar Andrés 《Journal of Soils and Sediments》2009,9(6):555-567
Background, aim, and scope
Nonylphenol polyethoxylates (NPEOs) are a widely used class of nonionic surfactants known to be toxic and endocrine-disrupting contaminants. Their use and production have been banned in the European Union and substituted by other surfactants considered as environmentally safer. However, their use continues in many countries without any legal control. Discharges of effluents from wastewater treatment plants and the application of sewage sludge application, landfilling, and accidental spillage to soils are the major sources of NPEOs in the environment. The biodegradation of these surfactants is relatively easy, leading to the accumulation of the simplest chemical forms of nonylphenol ethoxylates (NP, NP1EO, and NP2EO) and nonylphenol carboxy acids (NP2EC or NP1EC). However, these are also the most toxic end-products and have a higher environmental persistence. Compared to aquatic ecosystems, not much is known about the effects of NPEOs in terrestrial organisms, with few studies mainly centered on the effects on plants and soil microorganisms. The main aim of this study is to provide the range of concentrations of NPEOs with ecotoxicological effects on different plants and soil invertebrate species. In addition, we aim to identify the main soil properties influencing their toxicity. 相似文献125.
126.
Pilar Rallo 《The Journal of Horticultural Science and Biotechnology》2013,88(4):408-412
SUMMARYWe examined growth and development of the ‘Manzanilla’ olive fruit mesocarp in transverse equatorial sections during the first 12 weeks after full bloom (AFB). Sequential sampling and quantitative data provided an integrated view of the formation of this tissue. The mesocarp, or fruit flesh, was formed by relatively isodiametric parenchyma cells with a small number of isolated sclereids. By four weeks AFB a gradient in cell size characteristic of mature olive fruits began to appear. Biweekly measurements of cell size and number indicated that, as in other drupes, both cell division and expansion contribute to initial mesocarp growth. From six weeks AFB, further mesocarp growth was determined solely by cell expansion. Transverse areas of mesocarp and endocarp, also measured biweekly, revealed that both tissues expand in a similar manner until eight weeks AFB, after which mesocarp growth predominated. 相似文献
127.
José Wilacildo de Matos Oliveiro Guerreiro-Filho Wallace Gon?alves Daniel Alves Ramiro Bárbhara Joana dos Reis Fatobene 《Euphytica》2011,181(2):253-260
The coffee leaf miner, Leucoptera coffeella, is the most important pest of Coffea arabica plantations in Brazil, and all cultivars are susceptible to the insect. However, distinct reactions have been observed in
other species, such as C. congensis and C. canephora. In this work, the occurrence of antixenotic response was surveyed in individuals of Coffea species, selected for resistance to the leaf miner at both field and laboratory conditions. Tests performed on young plants
from C. arabica cultivars Icatu Precoce IAC 3282, Mundo Novo IAC 515-20, Tupi IAC 1669-33 and Catuaí Amarelo IAC 62 demonstrated that these
were preferred for oviposition when pooled with seedlings from C. canephora cv. Apoat? IAC 2258. Apoat? was also preferred over C. racemosa for oviposition. Similar results were observed in tests using detached leaves, and higher amount of eggs was counted in the
cv Obat? IAC 1669-20 and Catuaí Vermelho IAC 81, and lower oviposition frequency was observed in C. canephora cv. Guarini IAC 1598. C. congensis showed an oviposition frequency between C. arabica and C. canephora. Also, the results suggest that the frequency of oviposition is co-related with the plant resistance level, during larvae
infection. 相似文献
128.
López-Vázquez C García-Llobodanin L Pérez-Correa JR López F Blanco P Orriols I 《Journal of agricultural and food chemistry》2012,60(9):2242-2247
This study contributes fundamental knowledge that will help to develop a distillate of kiwi wine, made from kiwis of the Hayward variety grown in the southwest of Galicia (Spain). Two yeast strains, L1 (Saccharomyces cerevisiae ALB-6 from the EVEGA yeast collection) and L2 (S. cerevisiae Uvaferm BDX from Lallemand) were assessed to obtain a highly aromatic distillate. The kiwi spirits obtained were compared with other fruit spirits, in terms of higher alcohols, minor alcohols, monoterpenols, and other minor compounds, which are relevant in determining the quality and taste of the kiwi spirits. It was found that the kiwi juice fermented with yeast L1 produced a more aromatic distillate. In addition, kiwi distillates produced with both yeasts had the same ratio of trans-3-hexen-1-ol and cis-3-hexen-1-ol, which is lower than that found in other fruit distillates. 相似文献
129.
Tania Vidal Joana Luísa Pereira Nelson Abrantes Amadeu M V M Soares Fernando Gon?alves 《Water, air, and soil pollution》2012,223(9):6009-6023
Metal contamination of freshwater bodies resulting from mining activities or deactivated mines is a common problem worldwide such as in Portugal. Bra?al (galena ore) and Palhal (pyrrhotite, chalcopyrite, galena, sphalerite, and pyrite ore), located in a riverside position, are both examples of deactivated mining areas lacking implemented recovery plans since their shutdown in the early mid-1900s. In both mining areas, effluents still flow into two rivers. The purpose of this work was to evaluate the potential hazard posed by the mining effluents to freshwater communities. Therefore, short- and long-term ecotoxicological tests were performed on elutriates from river sediments collected at each site using standard test organisms that cover different functional levels (Vibrio fischeri, Pseudokirchneriella subcapitata, Lemna minor, and Daphnia sp.). The results show that elutriates from the sediments of Palhal were very toxic to all tested species, while in contrast, elutriates from Bra?al showed generally no toxicity for the tested species. Our study highlights the usefulness of using an ecotoxicological approach to help in the prioritization/scoring of the most critical areas impacted by deactivated mines. This ecotoxicological test battery can provide important information about the ecological status of each concerning site before investing in the application of time-consuming and costly methods defined by the Water Framework Directive or can stand as a meaningful complementary analysis. 相似文献
130.