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111.
Casas M Pujols J Rosell R de Deus N Peralta B Pina S Casal J Martín M 《Veterinary microbiology》2009,135(3-4):248-252
The objective of the present work was to ascertain the date in which hepatitis E virus (HEV) was introduced in the Spanish pig population. For this, a serological retrospective study was carried out using archived sera. A total of 2871 serum samples gathered between 1985 and 1997 and collected in 208 farms of Spain were tested for anti-HEV IgG by an in-house ELISA. Of the 2871 sera analyzed by ELISA, 1390 were positive for anti-HEV antibodies (48.4%, 95% CI: 46.9-49.9%) and that corresponded to 204/208 farms (98%, 95% CI: 96.1-99.9%) having at least one positive pig. Our results show that HEV was present and widespread in Spanish swine farms at least since 1985. Any significant changes in prevalence were detected from 1 year to another and therefore, HEV infection in swine should be considered endemic in Spain. 相似文献
112.
Bassarello C Bifulco G Montoro P Skhirtladze A Benidze M Kemertelidze E Pizza C Piacente S 《Journal of agricultural and food chemistry》2007,55(16):6636-6642
On the basis of the biological activities exhibited by the phenolic constituents of Yucca schidigera, the antioxidant activity of the methanol extract of Yucca gloriosa roots was evaluated in the TEAC assay. The strong activity exerted by this extract prompted investigation of its phenolic constituents, yielding three new phenolic derivatives, gloriosaols C, D, and E, along with gloriosaols A and B previously isolated from Y. gloriosa roots and yuccaols C-E isolated from Y. schidigera. ESIMS and NMR data of gloriosaols C-E closely resembled those reported for gloriosaols A and B, two diasteroisomers characterized by unusual spirostructures. Careful inspection of ROESY spectra revealed that gloriosaols C-E are diastereoisomers of gloriosaols A and B. A possible assignment of the relative configuration of gloriosaols C-E, derived according to an integrated NMR-quantum mechanical (QM) approach, which was already applied to the determination of the stereostructures of gloriosaols A and B, is also proposed. Gloriosaols A-E exhibited potent antioxidant activity measured by the TEAC assay, showing the potential use of Y. gloriosa as a source of antioxidant principles. 相似文献
113.
Development of a soil degradation assessment tool for organic olive groves in southern Spain 总被引:1,自引:0,他引:1
Forty-six organic olive orchards under different soil management systems were evaluated in the province of Córdoba (southern Spain) to assess the state of their soil properties and the degree of degradation of their topsoil, and the possibilities for monitoring any soil degradation risk. Our study indicated that 55% of the olive farms sampled (OF) presented a low soil degradation, in which most of their deficiencies were a low content in some soil nutrients such as P, which may be partly due to the moderate fertility of some soils in the area. This result could be explained by the low or moderate intensity of the farming systems used in a large part of the study area. Seven percent of the sampled OFs had a large number of physical, chemical and biological soil properties, that could be considered as being degraded, and these olive orchards were classified as seriously degraded. The remaining OFs were in an intermediate state. The degree of soil degradation was not correlated with any specific soil management method or with predicted soil erosion rates, suggesting that it was the result of specific and varied on-farm conditions difficult to detect without a field evaluation. Three soil degradation indexes were obtained through a principal component analysis of the soil properties analyzed. These indexes were able to distinguish between OFs with low soil degradation and those in a serious state of degradation. Two of the indexes are basically integrative ones that can be used in relatively large surveys considering a large number of soil properties. The third index developed used only three soil properties, organic C, water stable macroaggregates, and extractable P, and has the potential to be used as a relatively easy and inexpensive screening test of soil degradation for organic olive farms in the area. 相似文献
114.
SSR-based genetic diversity assessment among Tunisian winter barley and relationship with morphological traits 总被引:10,自引:1,他引:10
For studying genetic diversity caused byselection for adaptation and end-use, 17microsatellites (SSR), representative ofthe barley genome, were used in 26 barley(Hordeum vulgare L.) accessions andcultivars in Tunisia. Theaccessions/cultivars originate fromdifferent geographic regions and are ofdifferent end-use. For the 15 polymorphicSSR, the mean number of alleles per locuswas 3.6 and the average polymorphisminformation content was 0.45. Clusteranalysis based on SSR data and onmorphological data clearly differentiatethe genotypes according to their type(local landraces vs. varieties), row-numberand end-use. The correlation between bothdiversity measures was highly significant(r = 0.25, p<10-5) and thecorrespondence between the clustering basedon SSR and morphological data wasrelatively good. Our results show the largegenetic diversity of the Tunisian barleycultivars and the association of thisdiversity with adaptation traits. 相似文献
115.
Vinaixa M Marín S Brezmes J Llobet E Vilanova X Correig X Ramos A Sanchis V 《Journal of agricultural and food chemistry》2004,52(20):6068-6074
This paper presents the design, optimization, and evaluation of a mass spectrometry-based electronic nose (MS e-nose) for early detection of unwanted fungal growth in bakery products. Seven fungal species (Aspergillus flavus, Aspergillus niger, Eurotium amstelodami, Eurotium herbariorum, Eurotium rubrum, Eurotium repens, and Penicillium corylophillum) were isolated from bakery products and used for the study. Two sampling headspace techniques were tested: static headspace (SH) and solid-phase microextraction (SPME). Cross-validated models based on principal component analysis (PCA), coupled to discriminant function analysis (DFA) and fuzzy ARTMAP, were used as data treatment. When attempting to discriminate between inoculated and blank control vials or between genera or species of in vitro growing cultures, sampling based on SPME showed better results than those based on static headspace. The SPME-MS-based e-nose was able to predict fungal growth with 88% success after 24 h of inoculation and 98% success after 48 h when changes were monitored in the headspace of fungal cultures growing on bakery product analogues. Prediction of the right fungal genus reached 78% and 88% after 24 and 96 h, respectively. 相似文献
116.
Servili M Taticchi A Esposto S Urbani S Selvaggini R Montedoro G 《Journal of agricultural and food chemistry》2008,56(21):10048-10055
The sensory and health properties of virgin olive oil (VOO) are highly related to its volatile and phenolic composition. Oxygen control in the pastes during malaxation may be a new technological parameter to regulate enzymatic activities, such as polyphenoloxidase, peroxidase, and lipoxygenase, which affect the phenolic and volatile composition of VOO. In this work, we monitored CO2 and O2 concentrations during industrial-scale olive paste malaxation with various initial O2 concentrations within the malaxer headspace. Results show that the O2 concentration in the malaxer headspace did not affect CO2 production during processing, whereas a strong influence was observed on the changes of the phenolic composition of olive pastes and VOOs, with high correlation coefficient for the total phenols (R = 0.94), especially for oleuropein and demethyloleuropein derivatives (R = 0.81). In contrast, aroma production during malaxation was minimally affected by the O2 concentration in the malaxer headspace. 相似文献
117.
NITRATE UPTAKE KINETICS AND METABOLIC PARAMETERS IN TWO RICE VARIETIES GROWN IN HIGH AND LOW NITRATE
Leandro Azevedo Santos Walterliny Almeida Santos Marcus Vinícius Loss Sperandio Carlos Alberto Bucher Sonia Regina de Souza Manlio Silvestre Fernandes 《Journal of plant nutrition》2013,36(7):988-1002
A study was conducted on the effect of nitrate (NO3) levels on nitrate uptake kinetics and nitrogen (N) metabolism in two rice varieties, Piaui (landrace) and IAC-47 (improved). At 27 days after germination (DAG) N supply was suspended for 72 h, and then restored as 0.2 or 2 mM nitrate. The nitrate uptake kinetics was determined by the depletion method. Plants were harvested at 0, 6, and 24 h. Plants of the Piaui variety under 0.2 mM nitrate showed higher Vmax and lower KM, indicating higher efficiency of nitrate uptake at low supply. In the sheaths of both varieties, there was a greater accumulation of nitrate and lower activities of nitrate reductase and glutamine synthetase. The V-H+-ATPase activity increased between 0 and 6 h accompanying the nitrate influx, suggesting that the activity of this proton pump is necessary for the antiport activity (H+/2NO? 3) involved in the accumulation of nitrate into vacuoles. 相似文献
118.
Sonia de Caralt Javier Sánchez-Fontenla María J. Uriz Rene H. Wijffels 《Marine drugs》2010,8(6):1731-1742
Marine sponges produce secondary metabolites that can be used as a natural source for the design of new drugs and cosmetics. There is, however, a supply problem with these natural substances for research and eventual commercialisation of the products. In situ sponge aquaculture is nowadays one of the most reliable methods to supply pharmaceutical companies with sufficient quantities of the target compound. In this study, we focus on the aquaculture of the sponge Dysidea avara (Schmidt, 1862), which produces avarol, a sterol with interesting pharmaceutical attributes. The soft consistency of this species makes the traditional culture method based on holding explants on ropes unsuitable. We have tested alternative culture methods for D. avara and optimized the underwater structures to hold the sponges to be used in aquaculture. Explants of this sponge were mounted on horizontal ropes, inside small cages or glued to substrates. Culture efficiency was evaluated by determination of sponge survival, growth rates, and bioactivity (as an indication of production of the target metabolite). While the cage method was the best method for explant survival, the glue method was the best one for explant growth and the rope method for bioactivity. 相似文献
119.
Gina Cannarozzi Solomon Chanyalew Kebebew Assefa Abate Bekele Regula Blösch Annett Weichert Dominik Klauser Sonia Plaza-Wüthrich Korinna Esfeld Moritz Jöst Abiel Rindisbacher Habte Jifar Victoria Johnson-Chadwick Ermias Abate Wuyan Wang Rizqah Kamies Negussu Husein Worku Kebede Kidist Tolosa Yazachew Genet Kidu Gebremeskel Brikti Ferede Firew Mekbib Federico Martinelli Hans Christian Pedersen Suhail Rafudeen Shimelis Hussein Muluneh Tamiru Naomi Nakayama Mike Robinson Ian Barker Samuel Zeeman Zerihun Tadele 《Euphytica》2018,214(2):31
Indigenous crops also known as orphan crops are key contributors to food security, which is becoming increasingly vulnerable with the current trend of population growth and climate change. They have the major advantage that they fit well into the general socio-economic and ecological context of developing world agriculture. However, most indigenous crops did not benefit from the Green Revolution, which dramatically increased the yield of major crops such as wheat and rice. Here, we describe the Tef Improvement Project, which employs both conventional- and molecular-breeding techniques to improve tef—an orphan crop important to the food security in the Horn of Africa, a region of the world with recurring devastating famines. We have established an efficient pipeline to bring improved tef lines from the laboratory to the farmers of Ethiopia. Of critical importance to the long-term success of this project is the cooperation among participants in Ethiopia and Switzerland, including donors, policy makers, research institutions, and farmers. Together, European and African scientists have developed a pipeline using breeding and genomic tools to improve the orphan crop tef and bring new cultivars to the farmers in Ethiopia. We highlight a new variety, Tesfa, developed in this pipeline and possessing a novel and desirable combination of traits. Tesfa’s recent approval for release illustrates the success of the project and marks a milestone as it is the first variety (of many in the pipeline) to be released. 相似文献