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301.
Pigmentation capability of red porgy (Pagrus pagrus) skin reared under open sea‐cage conditions and fed an astaxanthin‐enriched diet was studied. Skin lipid peroxide levels and lipid composition were also evaluated to establish the antioxidant role of astaxanthin under these sunlight‐exposure conditions. Fish placed either in an offshore sea cage system (SC) or in an inland tank facility (T) housed inside a ‘shade‐house’ enclosure were fed a commercial diet supplemented with 22 mg kg?1 astaxanthin. No differences in growth or survival were found. Both groups displayed a red skin, but SC fish presented a darker pigmentation, which externally reflected the higher deposition of melanin, astaxanthin and tunaxanthin found in its skin. The lower level of lipid peroxides found in SC fish might be related with the higher level of astaxanthin mentioned above. Nevertheless, lipid and fatty acid profiles did not show significant differences between groups. Our results indicate that sustainable production of red porgy with a natural red hue is possible on the basis of proper adjustment of two factors illumination and dietary astaxanthin.  相似文献   
302.
The aim of this study was to assess the effect of two rearing conditions: outdoor environment with great volume tanks (500 m3) and low stocking density (~0.4 kg m?3); and indoor environment with smaller volume tanks (10 m3) and higher stocking density (~5 kg m?3), on muscle, liver and ovary lipid composition of Seriola dumerili broodstock born in captivity. The rearing conditions tested seem to affect the pattern of lipid body deposition in broodstock fish of S. dumerili, increasing the muscle and liver triacylglycerides (TG) accumulation of fish kept under indoor conditions, probably due to reduced energy expenditure in swimming, with some variations in the fatty acid profile that may respond to the differences in the culture conditions tested. No significant differences were found for Gonadosomatic Index (GSI) or ovary lipid deposition between groups in this study, which may suggest that the conditions tested do not have a major effect on ovary development. However, one season later the females kept under outdoor conditions released eggs spontaneously, whereas those kept under indoor conditions did not spawn, suggesting that the conditions tested actually have an effect on the broodstock's reproductive fitness. More studies are needed in order to evaluate whether the conditions tested have or not any influence on ovary development.  相似文献   
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Microalgae are microorganisms with a singular biochemical composition, including several biologically active compounds with proven pharmacological activities, such as anticancer, antioxidant and anti-inflammatory activities, among others. These properties make microalgae an interesting natural resource to be used as a functional ingredient, as well as in the prevention and treatment of diseases, or cosmetic formulations. Nevertheless, natural bioactives often possess inherent chemical instability and/or poor solubility, which are usually associated with low bioavailability. As such, their industrial potential as a health-promoting substance might be severely compromised. In this context, encapsulation systems are considered as a promising and emerging strategy to overcome these shortcomings due to the presence of a surrounding protective layer. Diverse systems have already been reported in the literature for natural bioactives, where some of them have been successfully applied to microalgae compounds. Therefore, this review focuses on exploring encapsulation systems for microalgae biomass, their extracts, or purified bioactives for food, pharmaceutical, and cosmetic purposes. Moreover, this work also covers the most common encapsulation techniques and types of coating materials used, along with the main findings regarding the beneficial effects of these systems.  相似文献   
305.
The main biological characteristics for black scabbardfish in the Canary Islands waters were established, focusing on its reproductive behaviour and strategy and its growth pattern. The sex proportion differs significantly from the 1:1 ratio, being clearly unbalanced towards the females. The sex ratio according to depth clearly shows the presence of male and female individuals in all the studied layers, thus sex segregation does not happen according to depth. The Canaries can be considered to be a reproduction site for A. carbo, since samples showing all stages of maturity have been observed. The gonadosomatic index (GSI) showed that the mean values were higher in the third and fourth quarters of the year. The index values clearly allow the differentiation of the individuals in resting or in spent (II and V) stages from individuals in ripe or in ripe and running stages, indicating that index levels higher than 2 are typical of maturation followed by spawning process. Up to twelve marks, assumed to be annuli, were visible in the sampled otoliths. Three to five years old were the dominant age classes and only 7.7% of fish were 7 years old or older. Age estimates ranged between 2 and 8 years for males and between 2 and 12 years for females. Estimated growth parameters were: L = 1477 ± 18.73 mm; k = 0.200 ± 0.016 year−1; and t0 = −4.58 ± 0.413 year. Biological aspects of the black scabbardfish suggest that this species has a generalist life-history strategy.  相似文献   
306.
The evaluation of Tiber River quality, in a stretch including a sewage treatment plant, has been carried out by the contemporary evaluation of water effect on Daphnia and benthic macroinvertebrates community structure. To achieve a good status of a river water by the end of 2015, as provided in the Water Framework Directive (WFD) 2000/60/EC, is necessary to know the quality starting point. To this end, several endpoints are expected by the WFD, including Daphnia toxicity test and macroinvertebrate community analysis. River water sampling was conducted in the four seasons, from upstream to downstream a sewage treatment plant. I endpoint. At the outfall of the sewage treatment plant, river water showed very high acute toxicity to Daphnia only in summer; some toxic effect can be found also upstream in spring. Results at the outfall were consistent with the hypothesis that disinfectants, mainly used in summer to treat discharging waters, are responsible of river water acute toxicity: Daphnia tests with each disinfectant (NaClO, PAA, ClO2) showed high toxicity. River waters were also utilized in Daphnia reproduction tests. Samples at the outfall (excluding the summer one, undoubtedly toxic) caused slight reduction in survival and fecundity. Disinfectants were also checked in reproduction tests. Still at NOEC24h, they caused a significant toxicity on both death rate and reproduction. II endpoint. Macroinvertebrate benthic community composition was evaluated upstream and downstream the sewage treatment plant, on these data Extended Biotic Index (EBI), was determined to get a score as quality class. A reduction of water quality score was found downstream the plant, one season delayed (autumn) respect the acute test on Daphnia. Effect of disinfectant discharge, river dilution capability on a short spatial scale and use of different endpoints are discussed in term of river stretch quality.  相似文献   
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  • 1. The fishing effort and turtle catch of vessels harbouring at Lampedusa island and fishing in the wider central Mediterranean area was monitored using a voluntary logbook programme. Two large trawlers were monitored between 2003 and 2005 and six small vessels using trawl nets, pelagic longline or bottom longline were monitored in the summer 2005.
  • 2. The observed turtle catch rates of pelagic longline and bottom trawl were among the highest recorded in the basin, and high catch rates by bottom longline were observed too. This suggests that the area contains major oceanic and neritic habitats for the loggerhead turtle Caretta caretta in the Mediterranean Sea.
  • 3. When fishing effort is considered, these results suggest a very high number of captures by Italian trawlers and longliners in the area, as well as by fleets from other countries. This is reason of concern for the conservation of the loggerhead turtle within the Mediterranean Sea.
  • 4. Different fishing gear have different technical/operational characteristics affecting turtle catch and mortality and the present knowledge about associated parameters of these gear varies too.
  • 5. All this considered, specific actions are recommended: (i) an awareness campaign to fishermen to reduce post‐release mortality, (ii) technical modifications to pelagic longline gear to reduce turtle catch, (iii) further investigation into turtle bycatch in all fishing gear, with priority given to bottom longline fishing and quantification of mortality caused by trawlers, (iv) assessment of the turtle populations affected by fishing activity in the area, and (v) international cooperation in undertaking threat assessments, and implementing regulations, management measures and monitoring.
Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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