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571.
Mozzarella stretching water (MSW) is a dairy effluent generated from mozzarella cheese production that does not have a real use and is destined to disposal, causing environmental problems and representing a high disposal cost for dairy producers. Spent brewery yeast (SBY) is another promising food waste produced after brewery manufacturing that could be recycled in new biotechnological processes. Aurantiochytrium mangrovei is an aquatic protist known as producer of bioactive lipids such as omega 3 long chain polyunsaturated fatty acids (ω3 LC-PUFA), in particular docosahexaenoic acid (DHA). In this work MSW and SBY have been used to formulate new sustainable growth media for A. mangrovei cultivation and production of DHA in an attempt to valorize these effluents. MSW required an enzymatic hydrolysis to enhance the biomass production. The new media obtained from hydrolysed MSW was also optimized using response surface methodologies, obtaining 10.14 g L−1 of biomass in optimized medium, with a DHA content of 1.21 g L−1.  相似文献   
572.
An in-depth study on the inhibitory mechanism on protein tyrosine phosphatase 1B (PTP1B) and aldose reductase (AR) enzymes, including analysis of the insulin signalling pathway, of phosphoeleganin, a marine-derived phosphorylated polyketide, was achieved. Phosphoeleganin was demonstrated to inhibit both enzymes, acting respectively as a pure non-competitive inhibitor of PTP1B and a mixed-type inhibitor of AR. In addition, in silico docking analyses to evaluate the interaction mode of phosphoeleganin with both enzymes were performed. Interestingly, this study showed that phosphoeleganin is the first example of a dual inhibitor polyketide extracted from a marine invertebrate, and it could be used as a versatile scaffold structure for the synthesis of new designed multiple ligands.  相似文献   
573.
An individual-based model for Sparus aurata was developed, taking into account the effects on the growth rate of water temperature, food availability and diet composition. The model was identified on the basis of the recent literature regarding the physiological ecology of this species. It was subsequently calibrated and validated by using original field data collected at two Italian fish farms located, respectively, in the Adriatic and Tyrrhenian Seas. The mass budget of uneaten food and faeces was computed using the model at each farm: the optimal ingestion rate of a fish was computed based on its wet weight and the temperature of the water, while the faeces estimation considered the different digestibility of lipids, carbohydrates and proteins in the diet. From an applied perspective, the future use of this growth model in relation to mariculture site selection and monitoring might typically be to estimate both the yield and the amount of uneaten food and faeces discharged from a fish cage. This second output represents a useful input for deposition models which are routinely used in the field of mariculture monitoring by different EU countries. The integration of growth and deposition models in a single system could provide a useful tool for the site-selection and monitoring of finfish mariculture operations in Mediterranean environments.  相似文献   
574.

BACKGROUND

The Japanese beetle Popillia japonica Newman is an insect pest native to Japan that has spread into North America, the Azores and, recently, into continental Europe. Here, we present a study assessing the effectiveness of a long-lasting insecticide-treated net (LLIN), assembled in semiochemical-baited attract-and-kill devices (A&Ks) as a low environmental impact means to control P. japonica in the field. We compared the attractiveness of three different forms of A&Ks that were left outdoors throughout the summer, and the residence time of P. japonica landing on them. Moreover, we performed a preliminary study testing the effectiveness of new LLINs after storage. Collected data also allowed us to investigate the beetles' diel flight patterns in relation to meteorological conditions.

RESULTS

Killing effectiveness of the field-exposed A&Ks declined steadily over the flight season (from 100% to 37.5%) associated with a decrease in residues of α-cypermethrin, the active ingredient in the LLINs. The different A&K forms (pyramidal, octahedral and ellipsoidal) attracted similar numbers of beetles. Individual beetles' residence time ranged from 75 to 95 s and differed slightly between A&K forms. Effectiveness of LLINs decreased by ≈30% after 1 year storage. Based on numbers landing on A&Ks, the beetles' flight activity peaked about 14:30 h and was inversely correlated with relative humidity.

CONCLUSION

This study indicates that semiochemical-baited A&Ks are effective for controlling P. japonica in the field. Because of active ingredient decay, the LLINs should be replaced after 30–40 days of field exposure to ensure that the A&Ks remain fully functional. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
575.

Background

The timely and flexible treatment of solid set canopy delivery systems (SSCDS) is expanding. Laboratory and field trials were conducted to evaluate the performance of three different irrigators (Pulsar™ system and nozzle combination), typically used in anti-frost and irrigation in vineyards/apple orchards, for plant protection product (PPP) delivery in a Guyot-trained trellised vineyard.

Results

Results showed that irrigator setups perform best when matched to the task—flat fan emitters for horizontal spray application (canopy top) and circular emitters for middle and low canopy application. A combination configuration of a double-sided flat fan and circular emitter system was indicated as the best option for homogenous coverage and minimal ground losses.

Conclusion

The tested emitters hold promise for SSCDS delivery of PPPs in vineyards. Further validation of the alternative use of this technology is warranted. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
576.
577.

Key message The application of the ITOC model allows the estimation of available biomass potentials from forests on the basis of National Forest Inventory data. The adaptation of the model to country-specific situations gives the possibility to further enhance the model calculations.

Context

With the rising demand for energy from renewable sources, up-to-date information about the available amount of biomass on a sustainable basis coming from forests became of interest to a wide group of stakeholders. The complexity of answering the question about amounts of biomass potentials from forests thereby increases from the regional to the European level.

Aims

The described ITOC model aims at providing a tool to develop a comparable data basis for the actual biomass potentials for consumption.

Methods

The ITOC model uses a harmonized net annual increment from the National Forest Inventories as a default value for the potential harvestable volume of timber. The model then calculates the total theoretical potential of biomass resources from forests. By accounting for harvesting restrictions and losses, the theoretical potential of biomass resources from forests is reduced and the actual biomass potentials for consumption estimated.

Results

The results from ITOC model calculations account for the difference between the amounts of wood measured in the forests and the actual biomass potentials which might be available for consumption under the model assumptions.

Conclusion

The gap between forest resource assessments and biomass potentials which are available for consumption can be addressed by using the ITOC model calculation results.
  相似文献   
578.
This paper presents a critical survey of some recent developments in the theory of international trade. Particular emphasis is given to the role of increasing returns to scale and labor mobility in shaping the pattern of industrial location across integrating countries. The goal is to review and discuss the novel insights and predictions of the so‐called “new” theories in order to pose and stimulate avenues for future research.  相似文献   
579.
Summary Some 238 landraces from Algeria and Tunisia representative of the mediterraneum typicum durum wheat type and 265 landraces from Syria and Jordan representing the syriacum type were grown in a semi-arid Mediterranean environment of Northern Syria characterized by moderate drought stress. The germplasm types were compared for mean value, level of variation and relationships with grain yield of various morpho-physiological traits possibly usable for indirect selection of best yielding materials. The syriacum germplasm showed higher yield mainly due to greater earliness of cycle, slightly longer grain filling period, shorter stature, lower early growth vigour and higher drought tolerance expressed by a visual score recorded in another, more stressful environment in the region. It also showed lower variation for all morpho-physiological characters except plant glaucousness, for which it was more variable. The wheat types differed not only for architecture but also for optima of individual morpho-physiological traits required to maximize the yield response in the given environment. Higher yield of syriacum materials was attained at same heading and three to four days delayed maturity with respect to average phenology of three well-adapted control cultivars, and it was favoured by increasing number of kernels per spike, early vigour and drought tolerance. Higher yield of mediterraneum typicum landraces was related to heading and maturity dates approaching those of the control cultivars and to increasing kernel weight, early vigour and drought tolerance. Plant stature hardly affected the yield. Both absent and strong glaucousness could confer a yield advantage in syriacum materials.  相似文献   
580.
Summary Foreign DNA was introduced into cell suspension cultures and leaf tissue of Eustoma grandiflorum Griseb. (lisianthus) by microprojectile bombardment. For this purpose a low-cost bombardment device that uses a helium flux to accelerate microprojectiles was built. When cell suspensions were used, an average of 4.1 Kan resistant calli were recovered per shot after 4 months' cultivation on selective medium. Most of the Kan resistant plants regenerated from calli were positive to GUS assay. Both the nptII and gus genes were successfully amplified from alkali-treated leaves of putative transgenic plants by PCR analysis. Transgenic plants were not recovered from bombarded leaves. Considering the host range specificity of Agrobacterium, and the response of the species to plant regeneration from suspension culture, microprojectile bombardment is, at present, the most efficient procedure for genetic transformation of lisianthus.Abbreviations BA 6-benzyladenine - Cx cefotaxime - 2,4 D (2,4-dichlorophenoxy) acetic acid - FDA fluorescein diacetate - gus -glucuronidase - IAA indole-3-acetic acid - IBA indole-3-butyric acid - 2iP (2-isopentenyl) adenine - Kan kanamycin - nptII neomycin phosphotransferase II - PCR polymerase chain reaction  相似文献   
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