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81.
82.
In plants, iron (Fe) and manganese (Mn) have many functions, as the transport and electron transference during photosynthesis, and their deficiencies affect the chlorophyll formation, plant growth and grain yield (GY). We carried out two experiments under greenhouse conditions with the aim of determining the influence of Fe and Mn on nutritional status, physiological components, soil chemical properties and yield components of soybean plants. In both experiments, five Fe and Mn rates were used. The GY, shoot dry weight yield (SDWY), the number of grain per pot (NGP), photosynthesis rate (A) and chlorophyll content were influenced by Fe rates, while GY, SDWY, root length and A were influenced by Mn rates. Iron and Mn concentrations in leaves and grains increased with rates of Fe and nutrients. The Mehlich 1 and DTPA-TEA extractants were efficient to determine the Fe and Mn available in the soil.  相似文献   
83.
The use of active biodegradable films from renewable sources like anchovy, with the incorporation of organic acids, such as sorbic acid (SA) and benzoic acid (BA), is an alternative to decrease environmental pollution and minimize the development of fungi in foods. This study investigated the respective influences of SA and BA at 0, 0.50, 0.75, and 1.50% on the growth of Aspergillus flavus and Rhizopus oryzae and on Argentine anchovy protein film properties (L*, a*, b*, tensile strength, elongation at break, solubility in water, water vapor permeability, and Fourier transform infrared spectroscopy (FTIR)). Results showed that the incorporation of SA or BA at different levels significantly increased the water vapor permeability, water solubility, and elongation at break of the films, but decreased the tensile strength and L* parameter (p < 0.05). FTIR evidenced an interaction between the BA and Argentine protein isolate. Also, the influences of the SA or BA concentration on antifungal activity was observed. The greatest effectiveness was obtained for films containing SA against R. oryzae compared to BA film treatments. In conclusion, the Argentine anchovy protein films could retain their antifungal property by incorporation of these organic acids.  相似文献   
84.
Expansion of soybean [Glycine max (L.) Merrill] cultivated in Brazil to regions with low fertility soils gave rise to studies on the possibility of obtaining highly productive cultivars with high nutrient use efficiency. An experiment in greenhouse conditions was conducted to assess phosphorus (P) use efficiency (PUE) by 13 soybean genotypes. The genotypes were grown in an Ustoxix Quartzipsamment with two P rates [0 (no P application) and 150 mg P kg?1], whose source was monoammonium phosphate (MAP, P2O5 44%). Shoot dry weight (SDW), grain yield (GY), grain harvest index (GHI), relative yield (RY), and physiological components (photosynthetic rate, stomatal conductance, respiratory rate, and internal CO2 concentration) were influenced by soybean genotypes and P rates. Genotypes BMX Apolo RR, BRS 360RR, BRS 378RR, CD 219RR, DM 2302RR, TMG 7161RR, and Vtop RR were classified as non-efficient and non-responsive to P application, while BMX Potência RR, Vmax RR, FPS Solar RR, NA 5909RR, TMG 1066RR, and M 6210 IPRO were classified as efficient and responsive. Phosphorus application increased the values of physiological components, which was not observed for N, K, Ca, Mg, and S concentration in the leaves and grains. Soybean genotypes selection for increased P efficiency could help growers overcome the problem of soybean cultivation on new areas or degraded pastures.  相似文献   
85.
The appropriate supply of magnesium (Mg) to the common bean (Phaseolus vulgaris L.) according to the requirements of each variety increases the productivity and nutritional value of grains. However, there are few studies on soil's ability to provide the adequate amount of the nutrient and on the reaction of plants with different Mg concentrations. The present study analyzed the response of the common bean plant to soil fertility, grain yield (GY), shoot dry weight (SDW) yield, nutritional status and the response of physiological components of the plant to the concentrations of Mg applied to the tropical soil. Thus, an experiment was conducted in a completely randomized design, in 5 × 4 factorial arrangement, with three replicates. The varieties BRS Estilo, IAPAR 81, BRS Ametista, IPR Campos Gerais (CG) and IPR Tangará were cultivated in an Ustoxix Quatzipsamment with five rates of Mg [0, 50, 100, and 200 mg kg?1, source magnesium chloride (MgCl2)]. The common bean varieties and the Mg rates significantly affected the soil chemical properties. Photosynthetic rate, stomatal conductance, transpiration rate, intercellular concentration of carbon dioxide (CO2), and total soluble sugars significantly correlated with common bean GY and SDW yield. The nutrient content in leaves and grains showed difference responses among the varieties. IAPAR 81 showed the highest rate of mobilization of nitrogen, phosphorus, magnesium, sulfur, boron, copper and zinc (N, P, Mg, S, B, Cu, and Zn) for grains, being an important factor in studies of crop biofortification.  相似文献   
86.
Soybean [Glycine max (L.) Merril] is the leading food crop worldwide, and selection of soybean genotypes for different levels of soil acidity may raise crop yield without the need to increase in planted area. An experiment in greenhouse conditions was conducted to determine the effects of two lime rates on soil chemical properties, grain yield (GY), yield components, nutritional status and physiological components of 15 soybean genotypes adapted to tropical and subtropical conditions. Genotypes BMX Apolo RR, BMX Potência RR, BRS 295RR, BRS 359RR, FPS Solar IPRO and TMG 716 IRR were the least responsive to soil acidity reduction, and BMX Turbo RR and BRS 360RR were the most responsive. Number of pods per pot, shoot dry weight yield, GY, photosynthesis, stomatal conductance, transpiration and chlorophyll increased significantly with increase in lime rate. Cultivar FPS Solar IPRO showed the highest foliar P, K, Ca and Mg concentrations in soybean, which was not observed in the grain, indicating the presence of genetic factors and the dilution effect on nutrient uptake.  相似文献   
87.
A 14-year-old spayed female domestic short-haired cat was presented for evaluation of a mass in the right eye. Ophthalmic examination revealed a blind right eye and presence of two distinct masses: a pink and a red-to-brown mass, the latter occupying most of the cornea and part of the conjunctiva. Exenteration was performed under general anesthesia, and the ocular tissues were processed routinely for histopathology. Upon microscopic examination, a malignant epithelial neoplasm and a benign vascular neoplasm were present in the cornea. The conjunctiva and the third eyelid were also affected. Upon immunohistochemistry, the epithelial tumor was positive for cytokeratin and negative for vimentin and the endothelial tumor was negative for cytokeratin and positive for vimentin. A diagnosis of squamous cell carcinoma (SCC) and hemangioma was made. The SCC was affecting the cornea, bulbar conjunctiva (lateral and inferior) and the base of the third eyelid, whereas the hemangioma was affecting the cornea and medial limbus. To the authors' knowledge, this is the first report of concomitant SCC and hemangioma affecting the ocular surface in a cat.  相似文献   
88.
The aim of this research was to formulate a unique product, croaker pâté, and to determine its physicochemical, microbiological, and sensorial characterization. Three formulations of pâté were elaborated. The pâtés fit in the stipulated regulations for the microbiological test. Regarding the texture, the pâtés presented a significant difference (p < 0.05) among each other. In the sensorial tests, the favorite pâté of the panel was formulation 3; in the acceptance test, it had higher levels of acceptance for color, flavor, and global acceptance in comparison with commercial pâté.  相似文献   
89.
The use of natural resources, especially processing wastes, as low cost and environmentally friendly alternative aiming high value-added applications is a subject of broad interest. Since the Brazilian silk production annually generates a large amount of waste during the silk fibers processing, this work explores the preparation and characterization of silk fibroin hydrogels using spinning waste silk fibers from textile processing and the processed ones. Hydrogels were obtained directly by dialyzing silk fibroin solutions against frequent changes of water until the gelation point and then lyophilized and characterized in terms of their morphology, crystallinity, thermal resistance and secondary structure. X-ray diffraction analysis revealed the presence of β-sheet conformation related to sol-gel transition. FT-IR spectra indicated the coexistence of random coil (silk I) and β-sheet (silk II) structures, with predominance of β-sheet conformation for hydrogels from processed silk fibers. From thermogravimetric analysis the presence of β-sheet secondary conformation was demonstrated by a degradation peak around 292 °C for both hydrogels. Freeze-dried hydrogels presented sheet or leaf like morphology and no significant change was observed among the hydrogels from waste silk fibers and processed ones. These characteristics suggest that silk fibroin hydrogels prepared from spinning waste silk fibers and obtained directly by dialysis can be potential candidates for biomaterials application, such as drug delivery systems and for wound dressings.  相似文献   
90.
Abstract

Continuous limestone application can inhibit the copper (Cu) uptake by plants. This experiment was carried out in greenhouse conditions using two soils (Typic Oxisol and Typic Entisol) with different clay and soil organic matter (SOM) levels to evaluate the effects of liming on Cu fertilization. The treatments consisted of two dolomitic limestone rates (0 and 7.5?g per pot, equivalent to 0 and 5.0?Mg ha?1) and five Cu rates (0, 2, 4, 8, and 16?mg kg?1). Regardless of the soil type, the limestone and Cu rate interaction did not affect the grain yield (GY), however, they did increase the productivity, shoot dry weight yield (SDWY), number of grains per pod, number of pods per pot, pod weight per pot, weight of 100 seeds, root volume, photosynthetic rate, and chlorophyll, and Ca, Mg, and Cu contents in the soil and leaves. It was concluded that for soybeans cultivated in Typic Entisol and Typic Oxisol, there was no association between 5.0?Mg ha?1 of limestone and the Cu rates. However, in isolation, limestone and Cu rate caused a significant increase in the soybean productivity, physiological components, and yield characteristics.  相似文献   
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