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241.
Allen R. Dedrick Eduardo Bautista Wayne Clyma David B. Levine Shirley A. Rish Albert J. Clemmens 《Irrigation and Drainage Systems》2000,14(1-2):41-67
Diagnostic Analysis (DA) is a methodologyfor assessing and understanding the performance of anagricultural system. This analysis is thefirst step in a large system change process, known asthe Management Improvement Program (MIP), whoseobjective is to improve the performance of the agricultural system.A group of Federal andstate of Arizona agencies agreed to apply the MIPmethodology in a western U.S. setting. The purpose of theapplication was to test the applicability of the MIPapproach and to refine themethodology. This paper describes how the DAmethodology was applied in the Maricopa-StanfieldIrrigation and Drainage District (MSIDD) area incentral Arizona, USA, and summarizes the lessonsderived from that experience. Specific findings ofthe DA study and the response of MSIDD areaagriculture to those findings are discussed inseparate articles. 相似文献
242.
Ernesto David Narvez‐Gonzlez Juan de Dios Figueroa‐Crdenas Suketoshi Taba Eduardo Castao Tostado Ramn lvar Martínez Peniche Froyln Rincn Snchez 《Cereal Chemistry》2006,83(6):595-604
Chemical composition (moisture, total lipids, protein, and apparent amylose) and some physical features (1,000 kernel weight, hardness, and anatomical composition) were determined in 71 accessions representing races of maize from Latin America. Their microstructural characteristics (size and compaction of endosperm cell bodies, pericarp thickness, horny‐floury endosperm ratio, and morphology and size of starch granules) were also evaluated using environmental scanning electron microscopy (ESEM). Compaction was the most important microstructural feature of the maize kernels, representing kernel hardness. Highly compact kernels tended to be hard, with high protein, pericarp, and hard‐endosperm content and high pericarp thickness, but with low moisture, amylose content, and kernel weight and size. The opposite was observed in the least compact kernels. Highly compact kernels tended to have small, polygonal starch granules (<10 μm), while the least compact kernels contained large, spherical granules (>10 μm). These results suggest that microstructure is responsible for the physical features of maize kernels and that microstructure is related to chemical composition. 相似文献
243.
Orihuela PL Picollo MI Audino PG Barrios S Zerba E Masuh H 《Pest management science》2006,62(11):1039-1044
New esterase substrates were synthesized using cis-, trans- and cis-trans-permethrinic acid chloride and then used to measure pyrethroid-cleaving enzymes in insects. The new substrates, namely cis-, trans- and cis-trans-7-coumaryl permethrates (7-CP), show a structure very similar to permethrin insecticide and yield fluorescent products on hydrolysis. These substrates were hydrolyzed by a commercial porcine preparation that provided esterase-specific activity, and were stable at different pH values (5.2-7.8). Studies made with house fly, Musca domestica (L.), homogenates showed that these compounds are appropriate for determining pyrethroid hydrolysis activity on individual insects. The measured activity of house fly esterase was 870 relative fluorescence units (RFU) min(-1) with cis-7-CP as substrate, 1117 RFU min(-1) with trans-7-CP as substrate and 1423 RFU min(-1) with cis-trans-7-CP as substrate. The fluorescent substrates for pyrethroid-cleaving esterases described in this paper have advantages over methods already given in the literature. They are substrates with structures very similar to pyrethroids, the cleavage of which can be followed by an increase in fluorescence emission at 440 nm; it takes only about 5 min to measure the reaction, and moreover the high sensitivity of the fluorescence technique allows the quantification of esterase activity on individual insects. 相似文献
244.
245.
246.
Weiss BP Berdahl JS Elkins-Tanton L Stanley S Lima EA Carporzen L 《Science (New York, N.Y.)》2008,322(5902):713-716
Angrites are among the oldest known pristine basaltic meteorites and record the earliest stages of planet formation and differentiation. Our paleomagnetic analysis of three angrites found that they record a past magnetic field of approximately 10 microteslas on the angrite parent body extending from 4564 to at least 4558 million years ago. Because the angrite paleomagnetic record extends beyond the expected lifetime of the early circumstellar disk, these paleofields were probably generated internally on the angrite parent body, possibly by an early dynamo in a rapidly formed metallic core. 相似文献
247.
Ruggero D Grisendi S Piazza F Rego E Mari F Rao PH Cordon-Cardo C Pandolfi PP 《Science (New York, N.Y.)》2003,299(5604):259-262
Mutations in DKC1 cause dyskeratosis congenita (DC), a disease characterized by premature aging and increased tumor susceptibility. The DKC1 protein binds to the box H + ACA small nucleolar RNAs and the RNA component of telomerase. Here we show that hypomorphic Dkc1 mutant (Dkc1m) mice recapitulate in the first and second generations (G1 and G2) the clinical features of DC. Dkc1m cells from G1 and G2 mice were impaired in ribosomal RNA pseudouridylation before the onset of disease. Reductions of telomere length in Dkc1m mice became evident only in later generations. These results suggest that deregulated ribosome function is important in the initiation of DC, whereas telomere shortening may modify and/or exacerbate DC. 相似文献
248.
Benedito Donizete Menozzi Giselle Souza da Paz Laís Moraes Paiz Hans Garcia Garces Brunna Mayla Vasconcelos Adorno Fernando Almeida‐Silva Rosely Maria Zancope Oliveira Virgínia Bodelo Richini‐Pereira Jssica Luana Chechi Eduardo Bagagli Sandra de Moraes Gimenes Bosco Helio Langoni 《Zoonoses and public health》2020,67(2):138-147
Bats are essential to the global ecosystem, but their ability to harbour a range of pathogens has been widely discussed, as well as their role in the emergence and re‐emergence of infectious diseases. This paper describes the first report of coinfection by two zoonotic agents, rabies virus (RABV) and the fungus Histoplasma suramericanum in a bat. The bat was from the Molossus molossus species, and it was found during the daytime in the hallway of a public psychiatric hospital in a municipality in São Paulo State, southeastern Brazil. RABV infection was diagnosed by the direct fluorescent antibody test and mouse inoculation test. The fungus was isolated by in vitro culture. Both diagnoses were confirmed by molecular techniques. Phylogenetic analysis showed that the fungus isolate had proximity to H. suramericanum in the Lam B clade, while the RABV isolate was characterized in the Lasiurus cinereus lineage. Since the M. molossus bat was found in a peri‐urban transition area (urban/peri‐urban), the possibility of cross‐species transmission of this RABV lineage becomes more plausible, considering that this scenario may provide shelter for both M. molossus and L. cinereus. These are relevant findings since there has been an increase in bat populations in urban and peri‐urban areas, particularly due to environmental modifications and anthropogenic impacts on their habitat. Thus, the detection of two zoonotic agents in a bat found in a public hospital should raise awareness regarding the importance of systematic surveillance actions directed towards bats in urban areas. 相似文献
249.
Coggan JS Bartol TM Esquenazi E Stiles JR Lamont S Martone ME Berg DK Ellisman MH Sejnowski TJ 《Science (New York, N.Y.)》2005,309(5733):446-451
Neurotransmitter release is well known to occur at specialized synaptic regions that include presynaptic active zones and postsynaptic densities. At cholinergic synapses in the chick ciliary ganglion, however, membrane formations and physiological measurements suggest that release distant from postsynaptic densities can activate the predominantly extrasynaptic alpha7 nicotinic receptor subtype. We explored such ectopic neurotransmission with a novel model synapse that combines Monte Carlo simulations with high-resolution serial electron microscopic tomography. Simulated synaptic activity is consistent with experimental recordings of miniature excitatory postsynaptic currents only when ectopic transmission is included in the model, broadening the possibilities for mechanisms of neuronal communication. 相似文献
250.
Leonardo Recena Aydos Luane Aparecida do Amaral Ana Cristina Jacobowski Roberta Serafim de Souza Eduardo Benedetti Parisotto Mariana Biava de Menezes Felipe Francisco Bittencourt Junior Emely Schuindt Fernandes Iandara Schettert Silva Luciane Candeloro Portugal Cláudio Gonçalves Oliveira Gustavo Tsuyoshi Senra Masuko Leandro Fontoura Cavalheiro Carlos Eduardo Domingues Nazário Elisvânia Freitas dos Santos Maria Lígia Rodrigues Macedo 《Journal of animal physiology and animal nutrition》2021,105(2):364-375
Metabolic syndrome (MetS) and obesity are growing in many parts of the world, becoming public health problems. It is proposed that foods with functional properties can assist in the treatment of these diseases. Crude buriti pulp oil (BPO) is a food traditionally consumed by residents in the Pantanal, Cerrado and Brazilian Amazon. It is rich in oleic acid, tocopherols and carotenoids, emerging as a potential functional food. Thus, this study aimed to evaluate the effect of the supplementation of BPO on metabolic disorders caused by a high-fat diet. Four groups of C57BL6 mice were used, a lean group with AIN-93M diet and control oil supplementation, an obese group with a high-fat diet and control oil supplementation, and two obese groups with a high-fat diet and BPO supplementation in the amounts of 50 and 100 mg/kg. BPO worsened the metabolic state caused by the high-fat diet, worsening risk factors associated with MetS, as the abdominal circumference and retroperitoneal fat, serum levels of total cholesterol, uric acid, alanine transaminase, glucose and triglycerides, and renal fat, in addition to changes in glycaemic control and oxidative stress markers. C57BL/6 mice fed with a high-fat diet and supplemented with BPO presented a worsening in metabolic risk factors associated with MetS. 相似文献