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61.
The suitability of plantation monocultures for the conservation of forest animals is an issue under continous debate. The adaptability of forest dwellers and the forest management regime seem to play key roles. In this study, I investigated the habitat selection of a generalist bird, the great spotted woodpecker (Dendrocopos major), within a pine (Pine spp.) monoculture, as well as the importance of the native habitat features within the pine matrix for the species’ conservation. I compared 52 plots with woodpecker presence against 121 plots where the species was absent, as well as 68 nest-trees against 90 random ones. Regression analyses were used to investigate the habitat attributes involved in the habitat selection. Although the great spotted woodpecker is considered a generalist forest dweller, it shows a marked habitat selection. Based on presence/absence records, the woodpecker prefers well-forested patches with high levels of tree diversity and with good coverage of a secondary species such as the strawberry tree (Arbutus unedo). To excavate their nests, woodpeckers select large trees in patches where other trees are also larger, rejecting patches with a high number of small trees. The most striking conclusion from this work is the preference shown for native trees, especially Portuguese oaks (Quercus faginea), as nest-trees. This is noteworthy because native trees are smaller and they are surrounded by smaller trees than pines. These findings support that woodpecker conservation benefits from an increase of habitat heterogeneity, particularly by the retention of native woodland patches within the plantation matrix. 相似文献
62.
Liliam Cristina Angelo Antonio Salvio Mangrich Karen Mary Mantovani Sailer Santos dos Santos 《Journal of Soils and Sediments》2014,14(2):353-359
Purpose
Charcoal is utilized in Brazil for the metallurgical industry. Small size pieces, called charcoal fines, are rejected and sometimes are used to produce energy by burning. This charcoal can be used as soil conditioner to improve retention of metal ions in soil. However, changing the charcoal's surface chemistry via oxidation may increase retention of metal ions.Materials and methods
Two kinds of oxidants were employed, nitric acid and selenium dioxide/hydrogen peroxide. Vanadyl ion (VO2+) and copper ion (Cu2+) were utilized as probe to study the metal ion complexation by the partially oxidized charcoal obtained. FTIR and EPR spectroscopy were used to characterize the materials.Results and discussion
Oxidation with nitric acid increased nitrogen content, while oxidation with SeO2/H2O2 elevated carbon content of treated charcoals. Organic free radicals (OFRs) with the unpaired electron in p orbitals of aromatic structures were confirmed by the EPR g-factors that ranged from 2.0038 to 2.0031. The oxidation with selenium dioxide/hydrogen peroxide formed charcoal with largest quantity of OFR. Loading charcoal with VO2+ and Cu2+ resulted in formation of complexes were oxygen acted as coordination atom. The formed complexes were of axial symmetry. The configurations around the Cu2+ ions were: CUNCu2+ complex (more stable square planar symmetry) and CFNCu2+ complex (less stable distorted tetrahedral configuration). Both complexes had oxygen as coordinating atoms. CFNVO2+ and CFSeVO2+ complexes presented complexation sites of axial symmetry, C4v, with oxygen as coordinating atoms.Conclusions
The oxidative treatment of charcoal with SeO2/H2O2 is more appropriate to produce soil organic conditioner for complexation of metal ions. 相似文献63.
64.
To evaluate differences in growth and adaptability of maritime pine (Pinus pinaster Ait.), we studied growth, polycyclism, needle tissue carbon isotope composition (delta(13)C) as an estimate of water-use efficiency (WUE) and survival of seven populations at 10 years of age growing in a performance trial at a provenance test site in Escaroupim, Portugal. Six populations were from relatively high rainfall sites in Portugal and southwestern France (Atlantic group), and one population was from a more arid Mediterranean site in Spain. There were significant differences between some populations in total height, diameter at breast height, delta(13)C of bulk needle tissue, polycyclism and survival. A population from central Portugal (Leiria, on the Atlantic coast) was the tallest and had the lowest delta(13)C. Overall, the variation in delta(13)C was better explained by the mean minimum temperatures of the coldest month than by annual precipitation at the place of origin. Analyses of the relationships between delta(13)C and growth or survival revealed a distinct pattern for the Mediterranean population, with low delta(13)C (and WUE) associated with the lowest growth potential and reduced survival. There were significant negative correlations between delta(13)C and height or survival in the Atlantic group. Variation in polycyclism was correlated with annual precipitation at the place of origin. Some Atlantic populations maintained a high growth potential while experiencing moderate water stress. A detailed knowledge of the relationships between growth, survival and delta(13)C in contrasting environments will enhance our ability to select populations for forestry or conservation. 相似文献
65.
Santos TC Marques MS Menezes IA Dias KS Silva AB Mello IC Carvalho AC Cavalcanti SC Antoniolli AR Marçal RM 《Fitoterapia》2007,78(5):333-336
The aqueous extract of Hyptis suaveolens leaves was studied for their antinociceptive property in chemical and thermal models of nociception in mice. Oral administration of the aqueous extract (100, 200, and 400 mg/kg) dose-dependently reduced the number of writhings induced by acetic acid, decreased the licking activity of the early phase in formalin test and increased the reaction time in hot-plate test. The antinociceptive effect was significantly antagonized by naloxone (3 mg/kg; i.p.). Preliminary acute toxicity study showed that no animal death with doses up to 5 g/kg (p.o.). 相似文献
66.
67.
Rodrigo Schveitzer;Roberto Fábio Conway Baccarat;Carlos Augusto Prata Gaona;Wilson Wasielesky;Rafael Arantes; 《Reviews in Aquaculture》2024,16(2):785-795
Microbial flocs (bioflocs) present in the water of intensive culture tanks are formed by a variety of microorganisms and other kinds of particulate organic matter, such as faeces and uneaten feed. During shrimp culture, biofloc concentrations increase. It has been reported that some level of control over biofloc levels, which can be quantified by the concentration of total suspended solids (TSS), is necessary for the adequate performance of the system. Some authors suggest that TSS concentrations below 600 mg L−1 are more appropriate for the superintensive culture of the Pacific white shrimp Litopenaeus vannamei in biofloc technology (BFT). However, subsequent research results contradict some of the arguments supporting the suggested solids limits, for example, the impact of increased solids on gill obstruction and subsequent shrimp survival. Recent studies have also shown the relationship between the control of solids and other important aspects of the system not considered so far, such as the control of opportunistic bacteria. Therefore, this topic seems worthy of revisiting, and it will be helpful to find new guidance toward understanding the levels of bioflocs that should be kept in L. vannamei culture tanks. In this review, we addressed the reasons that led to the establishment and limitations of the current biofloc levels for L. vannamei culture. The effects of maintaining low and high levels of bioflocs on both shrimp performance and the culture system are also analysed. Finally, perspectives on the management of biofloc levels are discussed, highlighting the advantages and disadvantages of each proposed strategy. 相似文献
68.
Aline de Camargo Santos;Bruce Schaffer;Diane Rowland;Matthew Bremgartner;Pamela Moon;Barry Tillman;Edivan Rodrigues de Souza;Elias Bassil; 《Journal of Agronomy and Crop Science》2024,210(4):e12736
Water deficit priming through regulated deficit irrigation has been shown to be beneficial for peanut cultivation, leading to improved water-use efficiency during the crop cycle and enhanced stress acclimation. The effects of priming using water deficit can be heritable, but little is known about stress priming effects on the physiology and growth of successive generations undergoing water stress. Two experiments were conducted to assess cross-generational priming by determining physiological and growth responses of offspring of primed and non-primed peanut plants of two genotypes, COC-041 and New Mexico Valencia C (NMV-C), both previously found to be strongly responsive to priming. Seeds were collected from parental plants subjected to mild water stress by regulated deficit irrigation (primed) or adequate irrigation (non-primed). These seeds were then planted, and the offspring were monitored for physiological and growth responses to water stress, including on a whole-plant basis using a high-throughput physiological phenotyping platform and on individual leaves by periodic single-leaf measurements. Measurements included whole-plant transpiration (plant-Tr), root water uptake, leaf transpiration, stomatal conductance and net CO2 assimilation (leaf-Tr, leaf-gs, and leaf-A), leaf water and osmotic potential (leaf-Ψw and leaf-Ψo), leaf osmotic adjustment, leaf relative water content (leaf-RWC) and cumulative plant-Tr. Offspring of both genotypes from primed parent plants had faster early establishment, with more uniform germination, and more rapid initial seedling growth compared to offspring from non-primed parent plants. Although offspring of both non-primed and primed plants of both genotypes exhibited a significant reduction of plant-Tr, gas exchange, leaf-Ψw, leaf-Ψo, and leaf-RWC when exposed to water stress, offspring of primed plants showed increased water use efficiency through reduced leaf-gs, leaf-Tr and plant-Tr while maintaining leaf-A under water stress. Despite offspring of both primed and non-primed plants being susceptible to severe water stress, offspring of primed plants exhibited overall enhanced water use efficiency, leading to greater dry biomass production per gram of transpired water and a trend of less growth reduction due to water stress compared to offspring of non-primed plants, especially for the genotype COC-041. This study shows the potential of water deficit priming to promote cross-generational changes in physiological function under limited water availability, by enhancing crop stress acclimation in the next plant generation. 相似文献
69.
Hernández Juan Augusto Lepe Marissa Macedo Rafael Arredondo Victalina Cortez Carlos Eliseo García Luis Jorge Prado Omar 《Tropical animal health and production》2017,49(1):173-178
Tropical Animal Health and Production - A study was conducted with the objective to characterize the morphology of Socorro Island Merino sheep. A total of 67 sheep, 62 females, 26 purebred and 36... 相似文献
70.
Castro W. J. R. Zanine A. M. Ferreira D. J. Souza A. L. Pinho R. M. A. Parente M. O. M. Parente H. N. Santos E. M. 《Tropical animal health and production》2020,52(5):2461-2468
Tropical Animal Health and Production - The use of agricultural by-products might provide an important alternative to improve animal agriculture and to reduce feeding costs. The effects of... 相似文献