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11.
Building on the early works of Alfred Marshall, analyses of local economies have emphasized the spatial function of clusters and industrial districts in terms of external economies of localization and agglomeration. Recent literature has emphasized the importance of culture and the complementarities between culture and local tangible and intangible assets. This paper aims to provide an analytical foundation for these processes with a view to developing tools for policy design, analysis and evaluation. By “system‐wide cultural districts,” we refer to a new approach to local development where cultural production and participation present significant strategic complementarities with other production chains. In this view, culture drives the accumulation of intangible assets such as human, social, and cultural/symbolic capital, thereby fostering economic and social growth and environmental sustainability.  相似文献   
12.
Walnuts (Juglans regia L.) are relevant components of the Mediterranean diet providing important macronutrients, micronutrients and other bioactive constituents including unsaturated fatty acids, proteins, fiber, vitamins, minerals, phytosterols and polyphenols. Although the walnut beneficial effects in human health are widely recognized by a lot of epidemiologic studies very little is known regarding its effect on damaged DNA. The aim of the present study was to investigate the effect of Juglans regia L. ethanolic extract from kernel on the induction of DNA strand breaks by thiol/Fe3+/O2 mixed function oxidase, tert-butyl hydroperoxide or UVC radiations in acellular and cellular models. Plasmid DNA cleavage and fast Halo assay were used to monitor oxidative damage to DNA. Both approaches showed protection of oxidatively injured DNA. These results agree with a lot of scientific proofs which recommend walnut as dietary adjunct in health promotion and prevention as well as in treatment of lifestyle-related oxidative diseases.  相似文献   
13.
Summary Solanum commersonii Dun. is a diploid (2n=2x=24, 1EBN) wild species of potential value for potato breeding. It is a reproductively isolated species and cannot be crossed with Tuberosum haploids (2n=2x=24, 2EBN) or other diploid 2EBNSolanum species. In order to overcome the EBN barriers, triploid hybrids were produced between Phureja-Tuberosum haploid hybrids, which form 2n pollen grains by parallel spindles, and tetraploidS. commersonii. Microsporogenesis analysis of the triploids indicated a trend towards low values of chromosome distribution at Anaphase I; lagging chromosomes were often observed as well. Despite these abnormalities, the percentage of stainable pollen was very high, ranging from 5.0% to 74.3%. A high variation in pollen grain diameter was also evident. Parallel and tripolar orientation of spindles at Metaphase II of microsporogenesis was a common feature of all the triploids analyzed, but dyads and triads were observed at a very low frequency. Therefore, also the frequency of 2n pollen was very low; the different size of stainable pollen appears to represent the ploidy levels which are possible according to the distribution of chromosomes in Anaphase I. The results obtained also suggest thatS. commersonii could have minor genes acting at the end of meiosis in such a way that, despite the presence of parallel/tripolar spindles, dyads/triads are not formed.Contribution no. 124 from the Research Center for Vegetable Breeding.  相似文献   
14.
This study evaluates quantitatively the suitability of the use of site-specific socio-economic and environmental data as indicators to rapidly assess patterns of diversity and genetic erosion risk in cassava. Socio-economic data as well as farmers’ estimation of genetic erosion were collected in the study area, the Ucayali region of the Peruvian Amazon, through interviews with 285 cassava farmers in 50 communities, while diversity was assessed based on agromorphological characterization of 295 cassava accessions. Using multivariate regression analyses, 50 and 45% of the variation in respectively diversity and genetic erosion estimation could be explained by a selected set of socio-economic and environmental indicators. In both regression models four out of the total of 38 variables proved to contribute significantly (at p < 0.10 level). Additionally, the study revealed that farmers are a good direct source of information on the diversity present at community level, which can contribute to the development of methodologies to assess diversity more rapidly. The results of this study are valuable for the development of models to rapidly assess diversity dynamics in large areas.  相似文献   
15.
A 6-year study was conducted in an organically managed orange orchard located in Sicily (Southern Italy) to assess the effect of compost and organic fertiliser utilisation on soil quality. Adopting a randomised-block experimental design with three replicates, four treatments were carried out. In treatments 1 and 2, two different composts (C1 from distillery by-products and C2 from livestock waste) were applied. The plots of treatment 3 were fertilised using dried poultry manure. The control treatment was fertilised by mineral/synthetic fertilisers. In order to verify the hypothesis that composts and organic fertilisers improve soil fertility, soil quality was evaluated by selecting dynamic soil parameters, as indicators linked to C and N cycles. Total organic C, total N, C/N ratio, humified fraction, isoelectric focussing (IEF) of extracted organic matter, microbial biomass C, potentially mineralisable N under anaerobic conditions, potentially mineralisable C, C mineralisation quotient and metabolic quotient were determined for each sample. Moreover, the Community Level Physiological Profile (by Biolog technique) was defined, calculating derived functional biodiversity and versatility indexes. Parameters related to IEF and potentially mineralisable C showed significant differences among the treatments. Moreover, total C, total N and humification parameters tended to increase, while no differences were observed in biodiversity indexes. On these findings, it was concluded that composts and poultry manure only weakly affected soil properties, though they increased soil potentially available nutritive elements to crops.  相似文献   
16.
Coevolution of mammals and their gut microbiota has profoundly affected their radiation into myriad habitats. We used shotgun sequencing of microbial community DNA and targeted sequencing of bacterial 16S ribosomal RNA genes to gain an understanding of how microbial communities adapt to extremes of diet. We sampled fecal DNA from 33 mammalian species and 18 humans who kept detailed diet records, and we found that the adaptation of the microbiota to diet is similar across different mammalian lineages. Functional repertoires of microbiome genes, such as those encoding carbohydrate-active enzymes and proteases, can be predicted from bacterial species assemblages. These results illustrate the value of characterizing vertebrate gut microbiomes to understand host evolutionary histories at a supraorganismal level.  相似文献   
17.
A recent increasing demand in Western countries for pomegranate products by consumers is especially supported for the nutritional and medicinal characteristics, due to the antioxidant properties of this fruit. Some studies have been published on the morphological and biochemical characteristics of pomegranate fruits in some Mediterranean countries, but little information is available about the genotypes present in Italy and in particular in Apulia (Southeastern region of Italy). This study (2008–2009) evaluated morpho-pomological and chemical parameters of eight pomegranate genotypes localized in private small orchards. Significant differences were observed among the pomegranate genotypes for many of the parameters investigated. In particular, fruit weight ranged from 168.9 g (SouMol) to 574.9 g (SouOst), °Brix from 14.7 (ComTri) to 18.0 (SouMol), titratable acidity from 5.4 (ComMol) to 25.0 (SouTri) g/L. SouMol showed the highest polyphenols (97.1 mg/L) and vitamin C (236.3 mg/L) contents. Oil content of the seeds was between 5.90% and 10.30%, no differences have been observed for the fatty acid composition with conjugated linoleic acid (CLA) isomers as the most abundant fraction (81.23%). Considering all the evaluated parameters, and especially those referring to the organoleptic characteristics and antioxidants content, it must be stated that the best genotypes worthy to be considered from agricultural and industrial points of view were AdeSgi for fresh market and SouOst for the juice industry.  相似文献   
18.
The volatiles produced by leaves and fruits of Olea europaea cv. Olivastra Seggianese have been analyzed in two different phenological stages. Furthermore, the volatiles of the virgin olive oil obtained from ripe fruits has been characterized. The volatiles were sampled by means of two different techniques: hydrodistillation and SPME. Differences were observed between the two different collection times, the different organs, and sampling techniques. The major constituents were often aldehydes, particularly (E)-2-hexenal (9.8-48.0%); however, also many terpenoids have been identified, mainly (E,E)-alpha-farnesene (0.2-27.0%), linalool (0-3.6%), beta-caryophyllene (0-8.1%), and valencene (0-2.5%). This is the first investigation on this cultivar.  相似文献   
19.
Anthocyanins of red orange juices were analyzed by micro-HPLC coupled on-line with an MS detector equipped with an ESI source. The use of microcolumn HPLC greatly enhanced detection performance, allowing direct identification of the anthocyanins present in the orange juices. The use of a soft ionization technique allows detection of the molecular ions of the aglycons. Eight components were identified, five of them for the first time in red orange juice. Three additional anthocyanins were detected, of which only the aglycon was identified.  相似文献   
20.
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