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991.
T. G. Dobrovol’skaya A. V. Golovchenko A. V. Yakushev E. N. Yurchenko N. A. Manucharov I. Yu. Chernov 《Eurasian Soil Science》2017,50(4):470-475
The analysis of bacterial complexes, including the number, taxonomic composition, physiological state, and proportion of ecological trophic groups was performed in a high moorland related to different elements of the microrelief. The abundance of bacteria, their ability for hydrolysis of polymers and the share of r-strategists were found to be higher in the sphagnum hillocks than on the flat surfaces. The total prokaryote biomass was 4 times greater in the sphagnum samples from microhighs (hillocks). On these elements of the microrelief, the density of actinomycetal mycelium was higher. Bacteria of the hydrolytic complex (Cytophaga and Chitinophaga genera) were found only in microhigh samples. 相似文献
992.
Ala’a F. Eftaiha Nidal Qinna Iyad S. Rashid Mayyas M. Al Remawi Munther R. Al Shami Tawfiq A. Arafat Adnan A. Badwan 《Marine drugs》2010,8(5):1716-1730
Metronidazole, a common antibacterial drug, was incorporated into a hydrophilic polymer matrix composed of chitosan xanthan gum mixture. Hydrogel formation of this binary chitosan-xanthan gum combination was tested for its ability to control the release of metronidazole as a drug model. This preparation (MZ-CR) was characterized by in vitro, ex vivo bioadhesion and in vivo bioavailability study. For comparison purposes a commercial extended release formulation of metronidazole (CMZ) was used as a reference. The in vitro drug-release profiles of metronidazole preparation and CMZ were similar in 0.1 M HCl and phosphate buffer pH 6.8. Moreover, metronidazole preparation and CMZ showed a similar detachment force to sheep stomach mucosa, while the bioadhesion of the metronidazole preparation was higher three times than CMZ to sheep duodenum. The results of in vivo study indicated that the absorption of metronidazole from the preparation was faster than that of CMZ. Also, MZ-CR leads to higher metronidazole Cmax and AUC relative to that of the CMZ. This increase in bioavailability might be explained by the bioadhesion of the preparation at the upper part of the small intestine that could result in an increase in the overall intestinal transit time. As a conclusion, formulating chitosan-xanthan gum mixture as a hydrophilic polymer matrix resulted in a superior pharmacokinetic parameters translated by better rate and extent of absorption of metronidazole. 相似文献
993.
M. K. O’Neill C. C. Shock K. A. Lombard R. F. Heyduck E. B. G. Feibert D. Smeal R. N. Arnold 《Agroforestry Systems》2010,79(3):409-418
The rapid growth rates of hybrid poplar (Populus spp.) enable rotations of 3–6 years for biofuels or 10–15 years to obtain merchantable timber, but many clones are susceptible
to nutrient deficiencies when grown in alkaline soils. A 1995 Oregon study demonstrated that clone OP-367 (P. deltoides × P. nigra) was the only clone tested that performed well on alkaline soils. Tests in Colorado and New Mexico confirmed the adaptation
of this clone. A multi-clonal trial was established in 2003 at Farmington, New Mexico and Ontario, Oregon in order to screen
a larger number of clones for adaptability to alkaline soils. Trees were planted at 1.5 × 1.5 m spacing and irrigated by surface
drip irrigation. Diameter at breast height (DBH) and tree height were recorded annually (2003–2006); wood volumes (WVol) and
total aboveground biomass (TAB) were calculated from these measurements. Of the 25 clones tested, 19 were common to both sites.
Mean height was greater at the Ontario site through the first 3 years (2003–2005). By the end of four seasons, the tallest
Farmington entry was OP-367 at 9.4 m with 177 Mg ha−1 TAB while the tallest Ontario entry was Malheur-3 at 8.9 m with 195 Mg ha−1 TAB and several other clones had statistically similar production. Given the growth and productivity range at these two sites,
it is difficult to make generalizations across wide areas, but it appears feasible to identify clones suited to alkaline soils
in arid and semi-arid regions. 相似文献
994.
Anna Young-Mathews Steven W. Culman Sara Sánchez-Moreno A. Toby O’Geen Howard Ferris Allan D. Hollander Louise E. Jackson 《Agroforestry Systems》2010,80(1):41-60
Forested riparian buffers in California historically supported high levels of biodiversity, but human activities have degraded
these ecosystems over much of their former range. This study examined plant communities, belowground biodiversity and indicators
of multiple ecosystem functions of riparian areas across an agricultural landscape in the Sacramento Valley of California,
USA. Plant, nematode and soil microbial communities and soil physical and chemical properties were studied along 50-m transects
at 20 sites that represented the different land use, soil and vegetation types in the landscape. Riparian zones supported
greater plant diversity and nearly twice as much total carbon (C) per hectare compared to adjacent land managed for agricultural
uses, but had generally lower soil microbial and nematode diversity and abundance. When woody plant communities were present
in the riparian zone, plant diversity and species richness were higher, and soil nitrate and plant-available phosphorus levels
were lower. Belowground diversity and community structure, however, appeared to depend more on plant productivity (as inferred
by vegetation cover) than plant diversity or species richness. Greater plant species richness, nematode food web structure,
total microbial biomass, woody C storage and lower soil nitrate and phosphorus loading were correlated with higher visual
riparian health assessment scores, offering the possibility of managing these riparian habitats to provide multiple ecosystem
functions. 相似文献
995.
Allison L. O’Kell Barbara Ambros 《The Canadian veterinary journal. La revue veterinaire canadienne》2010,51(3):305-307
A 3-year-old Labrador retriever was presented to the Western College of Veterinary Medicine for a tibial plateau levelling osteotomy. While performing a pre-operative epidural, thiopental was inadvertently administered into the epidural space. Treatment included epidural saline flushing and intravenous methylprednisolone sodium succinate. No neurologic deficits were detected. 相似文献
996.
997.
Eva Guillamón Ana García-Lafuente Miguel Lozano Matilde D´Arrigo Mauricio A. Rostagno Ana Villares José Alfredo Martínez 《Fitoterapia》2010
Edible mushrooms are a valuable source of nutrients and bioactive compounds in addition to a growing appeal for humans by their flavors and culinary features. Recently, they have become increasingly attractive as functional foods for their potential beneficial effects on human health. Hence, food industry is especially interested in cultivated and wild edible mushrooms. 相似文献
998.
Claire Marsden Guerric le Maire José-Luiz Stape Danny Lo Seen Olivier Roupsard Osvaldo Cabral Daniel Epron Augusto Miguel Nascimento Lima Yann Nouvellon 《Forest Ecology and Management》2010
By allowing the estimation of forest structural and biophysical characteristics at different temporal and spatial scales, remote sensing may contribute to our understanding and monitoring of planted forests. Here, we studied 9-year time-series of the Normalized Difference Vegetation Index (NDVI) from the Moderate Resolution Imaging Spectroradiometer (MODIS) on a network of 16 stands in fast-growing Eucalyptus plantations in São Paulo State, Brazil. We aimed to examine the relationships between NDVI time-series spanning entire rotations and stand structural characteristics (volume, dominant height, mean annual increment) in these simple forest ecosystems. Our second objective was to examine spatial and temporal variations of light use efficiency for wood production, by comparing time-series of Absorbed Photosynthetically Active Radiation (APAR) with inventory data. 相似文献
999.
Daniel O. Morris Raymond C. Boston Kathleen O’Shea Shelley C. Rankin 《Veterinary dermatology》2010,21(4):400-407
It has been shown that people and pets can harbour identical strains of meticillin‐resistant (MR) staphylococci when they share an environment. Veterinary dermatology practitioners are a professional group with a high incidence of exposure to animals infected by Staphylococcus spp. The objective of this study was to assess the prevalence of carriage of MR Staphylococcus aureus (MRSA), MR S. pseudintermedius (MRSP) and MR S. schleiferi (MRSS) by veterinary dermatology practice staff and their personal pets. A swab technique and selective media were used to screen 171 veterinary dermatology practice staff and their respective pets (258 dogs and 160 cats). Samples were shipped by over‐night carrier. Human subjects completed a 22‐question survey of demographic and epidemiologic data relevant to staphylococcal transmission. The 171 human‐source samples yielded six MRSA (3.5%), nine MRSP (5.3%) and four MRSS (2.3%) isolates, while 418 animal‐source samples yielded eight MRSA (1.9%) 21 MRSP (5%), and two MRSS (0.5%) isolates. Concordant strains (genetically identical by pulsed‐field gel electrophoresis) were isolated from human subjects and their respective pets in four of 171 (2.9%) households: MRSA from one person/two pets and MRSP from three people/three pets. In seven additional households (4.1%), concordant strains were isolated from only the pets: MRSA in two households and MRSP in five households. There were no demographic or epidemiologic factors statistically associated with either human or animal carriage of MR staphylococci, or with concordant carriage by person–pet or pet–pet pairs. Lack of statistical associations may reflect an underpowered study. 相似文献
1000.
Carlos R. Cunha Author Vitae Emanuel Peres Author Vitae Raul Morais Author Vitae Ana A. Oliveira Author Vitae Samuel G. Matos Author Vitae Miguel A. Fernandes Author Vitae P.J.S.G. Ferreira Author Vitae Author Vitae 《Computers and Electronics in Agriculture》2010,73(2):154-164
This paper describes a Viticulture Service-Oriented Framework (VSOF) which turns around context elements or tags that are placed in the field and which can be decoded by mobile devices such as mobile phones or PDAs. The tags are used to automatically associate a field location to the relevant database tables or records and also to access contextual information or services. By pointing a mobile device to a tag, the viticulturalist may download data such as climatic data or upload information such as disease and pest incidence in a simple way, without having to provide coordinates or any other references, and without having to return to a central office. This work is part of an effort to implement a large-scale distributed cooperative network in the Douro Demarcated Region in Northeast Portugal, a region in which the effort makes particular sense due to the extremely variable topography and mesoclimates. The possibility of exchanging contextualized information and accessing contextualized services in the field, using well-known devices such as cell phones, may contribute to increase the rate of adoption of information technology in viticulture, and contribute to more efficient and closer-to-the-crops practices. 相似文献