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201.
Three olive cultivars (Oliva Nera di Colletorto, Noccioluta, and a probably a new local genotype) from two strictly related areas of Molise region (south-centre of Italy) were characterized by combining molecular data (eight SSRs analyzed on leaves) and morphological features (thirty-one parameters from leaves, drupes and pits). Both molecular and morphological analyses have shown a very good separation of the three endemic cultivars. A high correlation between morphological and molecular data was found using Mantel's test. The morphological traits of pits were less influenced by environmental pressure than the leaves and drupes; therefore, the pits are more affected by genetic control and might be considered a helpful tool for cultivar characterization and identification. Potential and limitations of three statistical models computed to perform cultivar identification by morphological measures is also discussed. We demonstrated that molecular and morphological analyses are useful for distinguishing new accessions and studying local varieties to preserve genetic diversity, even at small geographical scale in such an unequivocal way; hence the methodology could be proposed as a tool to discriminate widespread cultivars, with long genetic distances.  相似文献   
202.
Changes in the phenolic composition, phenol extractability indices, and mechanical properties occur in grape berries during the ripening process, but the heterogeneity of the grapes harvested at different ripening stages affects the reliability of the results obtained. In this work, these changes were studied in Nebbiolo grapes harvested during five consecutive weeks and then separated according to three density classes. The changes observed in chemical and mechanical parameters through the ripening process are more related to berry density than harvest date. Therefore, the winemaker has to select the flotation density according to the objective quality properties of the wine to be elaborated. On the other hand, the stiffer grapes were associated with a higher accumulation of proanthocyanidins. The harder grapes provided the higher concentration and extractability of flavanols reactive to vanillin, whereas the thicker ones facilitated the extraction of proanthocyanidins.  相似文献   
203.
This study was performed to assess the impact of glutathione on the reaction between (+)-catechin and carbonyl compounds in wine-related conditions. (+)-Catechin (0.50 mM) and either glyoxylic acid (0.25 mM) or acetaldehyde (0.25 mM) were added to a model wine system with 0.0, 0.25, and 2.5 mM of glutathione added. UPLC-DAD and LC-MS analysis showed that the formation of carbonyl-bridged (+)-catechin dimers was inhibited in the samples with a glutathione to carbonyl ratio of 10:1 compared to the samples without glutathione. At a ratio of 1:1, glutathione inhibited the acetaldehyde-bridged dimers but only had a minor impact on the glyoxylic acid-bridged dimers. Further investigations showed that this trend of inhibition by glutathione on the glyoxylic acid-derived dimer was independent of temperatures, 20 °C vs 45 °C, or the presence of metal ions, 0.2 mg/L copper(II) and 5 mg/L iron(II). (1)H NMR analysis and LC-MS analysis provided evidence that glutathione inhibited dimer formation via different mechanisms depending on the carbonyl compound. For acetaldehyde-derived dimers, the main mode of inhibition was the ability of glutathione to form a (methyl-glutathionyl-methine)-(+)-catechin complex. Alternatively, the formation of a glutathione-glyoxylic acid addition product impeded the reaction between glyoxylic acid with (+)-catechin. These results demonstrate that glutathione, at sufficient concentration, can have a substantial impact on carbonyl-derived polymerization reactions in wine-like conditions.  相似文献   
204.
Thirteen cultivars and two hybrids of Clementine fruits (Citrus clementina Hort. Ex. Tan) cultivated in Italy were characterized according to pH, titratable acidity, total soluble solids, total polyphenols, carotenoids, vitamin C, hesperidin, rutin, narirutin and naringin and radical scavenging activity. The presence of rutin in Clementine fruit juice is reported for the first time here. The results indicated that all chemical parameters statistically differentiated each cultivar (P < 0.001). In particular, principal component analysis showed a clear discrimination of five cultivars from all the other varieties based on vitamin C and total polyphenols for the Caffin cultivar, which showed also the highest antioxidant activity; narirutin for the Etna hybrid cultivar; hesperidin, rutin and total soluble solids for the SRA 89 cultivar; and naringin, hesperidin and rutin for the Esbal cultivar. Moreover, the Mandalate hybrid cultivar showed the lowest antioxidant activity as well as vitamin C and total polyphenols content, while titratable acidity and naringin level were the highest. The antioxidant activity assessed in all the fruits was closely correlated with vitamin C and total polyphenols content, rather than with the flavonoid compounds.  相似文献   
205.
206.
Coastal water bodies are a particularly heterogeneous resource, typified by high spatial and temporal variability that could influence the aquaculture in coastal zones. However, the development of coastal aquaculture may produce negative impacts on the coastal area by the potential release of nutrients and organic matter that can be a source of pollution in receiving waters. The aim of this paper was to evaluate the performance of constructed wetland in controlling the dynamics of deoxygenating matter (organic matter and ammonia) and eutrophicating matter [organic matter and soluble reactive phosphorus (SRP)] in the waters entering (inflow) and flowing out (outflow) from a coastal aquaculture fish farm. We observed that constructed wetland systems are effective in removing fractions of total suspended solids, COD, total ammonia nitrogen and SRP contained in the inflow water with higher efficiency in the spring period (60.37%, 14.89%, 65.38% and 17.6% respectively) than in the summer period (45.10%, 8.06%, 32.43% and 8.00% respectively). Similar pattern was recorded for the treatment of the outflow waters, showing that the wetland system reduced most of the deoxygenating and eutrophicating matter produced as a consequence of feeding and fish metabolic activity. During the summer season, high algae mortality can reduce the performance of the wetland system in the outflow water control; this lower efficiency could be improved by controlling the biomass of algae by vegetation harvesting.  相似文献   
207.

This work evaluated the effects of food frequencies and self-feeding on the behavior, performance, and blood biochemistry of Colossoma macropomum. Juveniles weighing 3.63?±?0.05 g were distributed in 27 aquariums (40 L), with six fish per aquarium, to evaluate nine treatments in three replications in a 12L:12D photoperiod. The treatments were 24-h self-feeding (SF); daytime self-feeding at will (SFD); nighttime self-feeding at will (SFN); and feeding at fixed frequencies of two (2D), four (4D), and six times (6D) daytime and twice (2 N), four (4 N), and six times (6 N) nightly. The treatments were offered in automatic feeders, with fixed frequencies programmed. Extruded commercial feed, with 46% protein, was used. The experimental period was 40 days. In the SF treatment, the animals exhibited 95.7% nocturnal and 4.3% diurnal feeding activity (p?<?0.05). In the treatment SFD and SFN, the animals showed feeding activity throughout the day and night. Final weight, weight gain, and total feed intake were higher for animals at fixed daytime and nighttime frequencies (p?<?0.05). Feed conversion was better for animals in SF, SFD, 4D, SFN, and 4 N (0.89, 0.76, 0.91, 0.85, and 0.88, respectively) (p?<?0.05). Cholesterol and high-density lipoproteins were lower for fish in SF, SFN, 2 N, 4 N, and 6 N (p?<?0.05). SF treatment animals had lower triglyceride content, 154.20 mg dL?1 (p?<?0.05). Colossoma macropomum has nocturnal food preferences, however, with remarkable plasticity. Juveniles of this species fed four times during the day or night show good performance. Dietary patterns influenced the blood metabolic indicators of this species and the periods studied.

  相似文献   
208.
Agroforestry Systems - Pepper producers are searching for more sustainable production systems. Shaded cultivation is presented as a management option to attenuate black pepper environmental...  相似文献   
209.
Understanding how soil fertility changes due to environmental conditions and stand-age-dependent for-est attributes is important for local-scale forest restoration.We evaluated the effects of stand-age-dependent forest attributes (plant community composition and litter stock)on soil and technosol fertility across two second-growth Atlantic forests (SGF) after the deposition of mining tail-ings in Mariana,southeastern Brazil.We hypothesized that technosol fertility in the SGF tailings is positively affected by plant community composition variability,stand age,and litter stock.We used total exchangeable bases and organic matter as fertility indicators for technosol and soil,and spe-cies composition and litter stock as stand-age-dependent forest attributes.Our results showed significant differences in the stand-age-dependent forest attributes and soil chemi-cal properties between the two forest patches (SGF tailing and SGF non-tailing) evaluated.Thus,there was a marked gradient of litter storage and fertility between soil and tech-nosol that can be important forest recovery indicators for the affected plant communities.Furthermore,according to the tested models,we corroborated the hypothesis that techno-sol fertility is positively affected by stand age,plant com-munity composition variability,and litter stock,which may contribute considerably to forest recovery on tailings.Our results demonstrate that the fertility predictors analyzed to explain the forest recovery on tailings can also be considered as ecological indicators for assessing forest restoration in areas impacted by mining tailings in Mariana.  相似文献   
210.
Lawsonia intracellularis infection causes proliferative enteropathy (PE) in many mammalian species, with porcine and equine proliferative enteropathy (PPE and EPE) known worldwide. Hamsters are a well-published animal model for PPE infection studies in pigs. There is no laboratory animal model for EPE infection studies and it is not known whether there is species-specificity for equine or porcine isolates of L. intracellularis in animal models. The objective of this study was to determine whether it is possible to generate typical EPE lesions in hamsters after inoculation with an equine strain of L. intracellularis (EPE strain) and whether it is comparatively possible to generate PPE lesions in rabbits after inoculation with a porcine strain of L. intracellularis (PPE strain). In 2 separate trials, 4-week-old and 3-week-old weanling golden Syrian hamsters were challenged with EPE strains and compared to uninfected (both trials) and PPE-infected controls (Trial 2 only). Concurrently, 6 female New Zealand white juvenile rabbits were infected with PPE strain and observed concomitantly to 8 similar rabbits infected with EPE strain for a different experiment. Hamsters and rabbits were observed for 21 to 24 days post-infection (DPI), depending on the experiment. Neither infected species developed clinical signs. The presence of disease was assessed with diagnostic techniques classically used for pigs and horses: immune-peroxidase monolayer assay on sera; quantitative polymerase chain reaction (qPCR) detection of molecular DNA in feces; and hematoxylin and eosin (H&E) stain and immunohistochemistry (IHC) on intestinal tissues. Our results showed that EPE-challenged hamsters do not develop infection when compared with PPE controls (IHC, P = 0.009; qPCR, P = 0.0003). Conversely, PPE-challenged rabbits do not develop typical intestinal lesions in comparison to EPE-challenged rabbits, with serological response at 14 DPI being significantly lower (P = 0.0023). In conclusion, PPE and EPE strains appear to have different host-specificities for hamsters and rabbits, respectively.  相似文献   
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