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311.
Fábio Alex Custódio André W. C. Rosado Roberto Lanna Filho José Antonio Martinelli Miguel Dall’Agnol Rodrigo R. Lopes Olinto L. Pereira 《Plant pathology》2021,70(1):110-122
In Brazil, Paspalum species are commonly used in sports lawns, landscape projects, and as forage for livestock. Paspalum guenoarum plants showing symptoms of take-all disease were observed in the state of Rio Grande do Sul, Brazil. The fungus Gaeumannomyces graminis is the only species reported associated with this disease on Paspalum. In recent years, new species of Gaeumannomyces have been proposed based on molecular studies, which demonstrated the existence of a species complex. Take-all affects rice and wheat, but the aetiology of this disease on P. guenoarum is still unknown; this work aimed to elucidate the aetiology of the take-all on P. guenoarum in Brazil and evaluate possible alternative hosts of agricultural importance. Based on combined phylogenetic analyses of ITS, LSU, TEF-1α, and RPB1 sequences, the fungal pathogen was identified as Atripes paspali gen. et sp. nov., which is proposed as a new genus in the Magnaporthaceae family. A representative isolate of A. paspali was inoculated on healthy P. guenoarum plants and reproduced the same symptoms of take-all observed in the field. Furthermore, this fungus is also able to cause take-all on wheat plants; temperature directly affected the incidence and development of the disease in wheat. Take-all on P. guenoarum is caused by A. paspali. 相似文献
312.
This paper presented a conceptual framework to country competitiveness using the Index of Competitiveness (IVCR), revealed for Ecuador to determine the most competitive and potential products exported to China; also measured the export complementarities through other indicators and by comparison with similar products exported by competing countries. This study used the 6-digit Harmonized System (HS) and the 10-digit NANDINA tariff codes for more specific items. Thereby we can identify trends that allow the Ecuadorian authorities analyze the state of bilateral agreements and develop action strategies, moreover help exporters identify potential market niches, considering that China is currently one of the developing countries with higher growth and expanding economy. The results showed that the most competitive agricultural products consisted on fish flour, bovine skins, mollusks, fish wastes and cocoa grains. The founded potential products were broad beans, fruits, fish viscera, algae, alpaca hair or hair wastes. Nevertheless these were none adding value commodities we need to find some mechanisms to deepen the exportable offer of value-added goods. 相似文献
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315.
A Mubarak CP Bondonno AH Liu MJ Considine L Rich E Mas KD Croft JM Hodgson 《Journal of agricultural and food chemistry》2012,60(36):9130-9136
There is mounting evidence that specific dietary polyphenols can enhance vascular health by augmenting nitric oxide. Our aim was to investigate the acute effects of chlorogenic acid, an important dietary phenolic acid present in coffee (400 mg, equivalent to 2 cups of coffee), on nitric oxide status, endothelial function, and blood pressure. Healthy men and women (n = 23) were recruited to a randomized, double-blind, placebo-controlled, crossover trial. Chlorogenic acid resulted in significantly higher plasma concentrations of chlorogenic acid (P < 0.001). Relative to control, the mean post-treatment systolic blood pressure (-2.41 mmHg, 95% CI: -0.03, -4.78; P = 0.05) and diastolic blood pressure (-1.53 mmHg, 95% CI: -0.05, -3.01; P = 0.04) were significantly lower with chlorogenic acid. Markers of nitric oxide status (P > 0.10) and the measure of endothelial function (P = 0.60) were not significantly influenced. Chlorogenic acid can lower blood pressure acutely, an effect that, if sustained, would benefit cardiovascular health. 相似文献
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Apparent electrical conductivity of soil (ECa) is a property frequently used as a diagnostic tool in precision agriculture, and is measured using vehicle‐mounted proximal sensors. Crop‐yield data, which is measured by harvester‐mounted sensors, is usually collected at a higher spatial density compared to ECa. ECa and crop‐yield maps frequently exhibit similar spatial patterns because ECa is primarily controlled by the soil clay content and the interrelated soil moisture content, which are often significant contributors to crop‐yield potential. By quantifying the spatial relationship between soil ECa and crop yield, it is possible to estimate the value of ECa at the spatial resolution of the crop‐yield data. This is achieved through the use of a local regression kriging approach which uses the higher‐resolution crop‐yield data as a covariate to predict ECa at a higher spatial resolution than would be prudent with the original ECa data alone. The accuracy of the local regression kriging (LRK) method is evaluated against local kriging (LK) and local regression (LR) to predict ECa. The results indicate that the performance of LRK is dependent on the performance of the inherent local regression. Over a range of ECa transect survey densities, LRK provides greater accuracy than LK and LR, except at very low density. Maps of the regression coefficients demonstrated that the relationship between ECa and crop yield varies from year to year, and across a field. The application of LRK to commercial scale ECa survey data, using crop yield as a covariate, should improve the accuracy of the resultant maps. This has implications for employing the maps in crop‐management decisions and building more robust calibrations between field‐gathered soil ECa and primary soil properties such as clay content. 相似文献
318.
Carlos R. Fonseca Gislene Ganade Ronei Baldissera Carlos R. Boelter Lucas M. Campos Vanda S. Fonseca Fernando Joner Ana M. Leal-Zanchet Alex S. Mesquita Claudia P. Paz Fabio N. Piovensan Anamaria Stranz Emerson M. Vieira 《Biological conservation》2009,142(6):1209-31
Since pristine Atlantic Forest remnants are vanishing, and biological reserves are in short, conservation of biodiversity will largely depend on proper management of the anthropogenic matrix. Here, we test (1) the effectiveness of ecologically-managed tree monocultures in maintaining Araucaria Forest biodiversity, (2) how this effectiveness change among taxa, and (3) we discuss management principles that can be used by the forestry industry in order to contribute positively to biodiversity conservation. The study was conducted in the São Francisco de Paula National Forest, southern Brazil, an environmental mosaic composed mostly of patches of Araucaria Forest and ecologically-managed monocultures of Araucaria, Pinus and Eucalyptus. Using standardized sampling methods in these four main habitats, we have recorded the richness and species composition of small mammals, birds, leaf-litter frogs, butterflies, galling insects, spiders, opiliones, flatworms, woody plants, epiphytic angiosperms, epiphytic ferns, lichens, and fruit-body producing fungi. Overall, we recorded 506 species in Araucaria Forest, 181 (36%) of which were exclusive of this habitat while 325 (64%) could be found in at least one monoculture. Distribution patterns of species richness and number of records across taxonomic groups showed that a large biodiversity can be found inside ecologically-managed plantations of Araucaria, Pinus, and Eucalyptus. For all studied taxa, except for epiphytic angiosperms and fruit-body producing fungi, more than half of the Araucaria Forest species could be found living on monocultures. We discuss how the actual management practices of the forest industry can be improved to contribute positively to the conservation of the Atlantic Forest biodiversity. 相似文献
319.
320.
Bermejo M Rodríguez-Teijeiro JD Illera G Barroso A Vilà C Walsh PD 《Science (New York, N.Y.)》2006,314(5805):1564
Over the past decade, the Zaire strain of Ebola virus (ZEBOV) has repeatedly emerged in Gabon and Congo. Each human outbreak has been accompanied by reports of gorilla and chimpanzee carcasses in neighboring forests, but both the extent of ape mortality and the causal role of ZEBOV have been hotly debated. Here, we present data suggesting that in 2002 and 2003 ZEBOV killed about 5000 gorillas in our study area. The lag between neighboring gorilla groups in mortality onset was close to the ZEBOV disease cycle length, evidence that group-to-group transmission has amplified gorilla die-offs. 相似文献