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991.
Gisele Cristina dos Santos Bazanella Gabriel Francisco da Silva Angélica Marquetotti Salcedo Vieira Rosangela Bergamasco 《Water, air, and soil pollution》2012,223(9):6083-6093
The occurrence of fluoride in groundwater has been reported in many countries, mainly because the excess fluoride in drinking water can lead to dental or skeletal fluorosis. Fluoride removal by coagulation with Moringa oleifera seeds, followed by separation with membranes, was investigated in this work. Artificially fluoridated water, at a starting fluoride concentration of 10?mg?L?1, was submitted to a coagulation process with aqueous extracts of M. oleifera seeds. The coagulation process was followed by ultrafiltration with membranes at different pressures. The coagulation process with 2.5?g?L?1 of M. oleifera promoted a reduction of 90.90?% in the fluoride content of the treated water, making it possible for poor communities to consume this water. It is noteworthy that the combined coagulation/filtration process using raw coagulant showed the highest values of colour and turbidity, which, however, were still below the limits set for drinking water by Brazilian legislation. The advantage of proposing a sequential process using membrane separation is that it removes colour and turbidity, caused by the use of M. oleifera as a coagulant, resulting in water that meets potability standards. 相似文献
992.
993.
Jo?o Silva Dias 《Genetic Resources and Crop Evolution》2012,59(6):1201-1206
Portuguese perennial kale is a rare leafy vegetable and forage crop in Portugal. It may be a relic of a primitive kale form which could have been grown on a large scale in Portugal and in West Europe. This kale has strong branching habit with rosettes of leaves in the stems. It shows a strongly reduced flowering ability and for this reason is vegetatively propagated. In the past, perennial kale has probably been widely distributed in West Europe, but the crop has gradually declined in occurrence in this area. At present it is an almost extinct vegetable crop and by this reason deserves to be preserved. 相似文献
994.
995.
Daniel Bernardi Marcos Botton Uemerson Silva da Cunha Oderlei Bernardi Thibaut Malausa Mauro Silveira Garcia Dori Edson Nava 《Pest management science》2013,69(1):75-80
BACKGROUND: The spider mite, Tetranychus urticae, is the major strawberry pest in Brazil. The main strategies for its control comprise synthetic acaricides and predatory mites. The recent register of a commercial formula of azadirachtin (Azamax® 12 g L?1) can be viable for control of T. urticae. In this work, the effects of azadirachtin on T. urticae and its compatibility with predatory mites Neoseiulus californicus and Phytoseiulus macropilis in the strawberry crop were evaluated. RESULTS: Azadirachtin was efficient against T. urticae, with a mortality rate similar to that of abamectin. In addition, the azadirachtin showed lower biological persistence (7 days) than abamectin (21 days). Azadirachtin did not cause significant mortality of adult predatory mites (N. californicus and P. macropilis), but it did reduce fecundity by 50%. However, egg viability of the azadirachtin treatments was similar to that of the control (>80% viability). The use of azadirachtin and predatory mites is a valuable tool for controlling T. urticae in strawberry crop. CONCLUSIONS: Azadirachtin provided effective control of T. urticae and is compatible with the predatory mites N. californicus and P. macropilis. It is an excellent tool to be incorporated into integrated pest management for strawberry crop in Brazil. Copyright © 2012 Society of Chemical Industry 相似文献
996.
Ivan Cruz Maria de Lourdes Corrêa Figueiredo Rafael Braga da Silva Ivana Fernandes da Silva Cristiane deSouza Paula John E. Foster 《国际虫害防治杂志》2013,59(1):83-87
The fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), is a major pest of maize and frequently demands control measures. The timing of insecticide application is a key factor in determining its efficiency, so an experiment was designed to investigate this. Application of insecticide was based on three criteria: (i) the number of trap-caught moths in a Delta-type trap with a commercial sex pheromone lure placed in the center of the target area, soon after plant emergence; (ii) the percentage of plants exhibiting pinhole-type damage (10% or 20%) and (iii) the percentage of plants exhibiting shot hole-type damage (10% or 20%) compared to a check plot without any control measures. We found that the number of trap-caught moths was, compared to the other methods, the best means of deciding on insecticide application in maize to control the fall armyworm. Using pheromone traps, we obtained the best performance of the insecticide Spinosad, causing >90% larval mortality. Without insecticide application, maize yield reduction due to fall armyworm larva damage was 39%. 相似文献
997.
J. M. Serrano S. Shahidian J. R. Marques da silva 《European Journal of Soil Science》2014,65(4):562-572
The objective of this study was to test a simple input‐output model to estimate soil phosphorus (P) retention over 12 years in a Mediterranean pasture. A 6‐ha permanent pasture field in Southern Portugal was subjected to different management systems in terms of grazing and fertilizer application. The soil and pasture were monitored and samples were geo‐referenced with RTK GPS. The model was developed to explain the effect of P fertilizer, based on the premise that P added through fertilizer and amounts removed in harvested plant products are the main fluxes affecting available P status, and was used to estimate the soil P retention. The results show that P fertilizer addition to Mediterranean grazed pastures on shallow soils influences several P dynamics under different grassland management systems. A positive linear relationship between the P budgets and the changes in measured P was demonstrated over the study periods. This work highlights the difficulty associated with the creation of recommendation maps for differentiated P fertilizer application in pastoral systems and indicates that before any accurate decision making, the historic knowledge of changes in the concentrations of P in the soil should be considered, as well as a prediction of the residual effects of applied nutrient. The importance of this knowledge increases when the aim is to use techniques and technologies for variable‐rate fertilizer application and implementation of site‐specific management strategies in the context of precision agriculture. 相似文献
998.
Larissa Alves Guimar?es Paula Christine Jimenez Thiciana da Silva Sousa Hozana Patrícia S. Freitas Danilo Damasceno Rocha Diego Veras Wilke Jesús Martín Fernando Reyes Otília Deusdênia Loiola Pessoa Letícia Veras Costa-Lotufo 《Marine drugs》2014,12(12):5839-5855
The present study highlights the biological effects of chromomycin A2 toward metastatic melanoma cells in culture. Besides chromomycin A2, chromomycin A3 and demethylchromomycin A2 were also identified from the extract derived from Streptomyces sp., recovered from Paracuru Beach, located in the northeast region of Brazil. The cytotoxic activity of chromomycin A2 was evaluated across a panel of human tumor cell lines, which found IC50 values in the nM-range for exposures of 48 and 72 h. MALME-3M, a metastatic melanoma cell line, showed the highest sensitivity to chromomycin A2 after 48h incubation, and was chosen as a model to investigate this potent cytotoxic effect. Treatment with chromomycin A2 at 30 nM reduced cell proliferation, but had no significant effect upon cell viability. Additionally, chromomycin A2 induced accumulation of cells in G0/G1 phase of the cell cycle, with consequent reduction of S and G2/M and unbalanced expression of cyclins. Chromomycin A2 treated cells depicted several cellular fragments resembling autophagosomes and increased expression of proteins LC3-A and LC3-B. Moreover, exposure to chromomycin A2 also induced the appearance of acidic vacuolar organelles in treated cells. These features combined are suggestive of the induction of autophagy promoted by chromomycin A2, a feature not previously described for chromomycins. 相似文献
999.
da Matta CB de Souza ET de Queiroz AC de Lira DP de Araújo MV Cavalcante-Silva LH de Miranda GE de Araújo-Júnior JX Barbosa-Filho JM de Oliveira Santos BV Alexandre-Moreira MS 《Marine drugs》2011,9(3):307-318
Marine natural products have been the focus of discovery for new products of chemical and pharmacological interest. The aim of this study was to evaluate the antinociceptive activity of the methanolic (ME), acetate (AE), hexanic (HE) and chloroform (CE) extracts obtained from Caulerpa mexicana, and ME, CE and HE obtained from Caulerpa sertularioides. These marine algae are found all over the world, mainly in tropical regions. Models such as the writhing test, the hot plate test and formalin-induced nociception test were used to evaluate antinociceptive activity in laboratory mice. In the writhing test, all the extracts were administered orally at a concentration of 100 mg/kg, and induced high peripheral antinociceptive activity, with a reduction in the nociception induced by acetic acid above 65%. In the hot plate test, treatment with extracts from C. sertularioides (100 mg/kg, p.o.) did not significantly increase the latency of response, although the ME, AE and HE from C. mexicana showed activity in this model. This result suggests that these extracts exhibit antinociceptive activity. In the formalin test, it was observed that ME, AE and HE obtained from C. mexicana reduced the effects of formalin in both phases. On the other hand only CE from C. sertularioides induced significant inhibition of the nociceptive response in the first phase. To better assess the potential anti-inflammatory activity of the extracts, the carrageenan-induced peritonitis test was used to test Caulerpa spp. extracts on cell migration into the peritoneal cavity. In this assay, all extracts evaluated were able to significantly inhibit leukocyte migration into the peritoneal cavity in comparison with carrageenan. These data demonstrate that extracts from Caulerpa species elicit pronounced antinociceptive and anti-inflamatory activity against several nociception models. However, pharmacological and chemical studies are continuing in order to characterize the mechanism(s) responsible for the antinociceptive action and also to identify the active principles present in the Caulerpa species. 相似文献
1000.
Dias MI Barros L Sousa MJ Ferreira IC 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(2):181-186
Coriander is commonly used for medicinal purposes, food applications, cosmetics and perfumes. Herein, the production of antioxidants
in vegetative parts (leaves and stems) of in vivo and in vitro grown samples was compared. In vitro samples were clone A- with notorious purple pigmentation in stems and leaves and clone B- green. Seeds were also studied
as they are used to obtain in vivo and in vitro vegetative parts. Lipophilic (tocopherols, carotenoids and chlorophylls) and hydrophilic (sugars, ascorbic acid, phenolics,
flavonols and anthocyanins) compounds were quantified. The antioxidant activity was evaluated by radical scavenging activity,
reducing power and lipid peroxidation inhibition. The in vivo sample showed the highest antioxidant activity mainly due to its highest levels of hydrophilic compounds. Otherwise, in vitro samples, mainly clone A, gave the highest concentration in lipophilic compounds but a different profile when compared to
the in vivo sample. Clones A and B revealed a lack of β-carotene, β- and δ-tocopherols, a decrease in α-tocopherol, and an increase in
γ-tocopherol and clorophylls in comparison to the in vivo sample. In vitro culture might be useful to explore the plants potentialities for industrial applications, controlling environmental conditions
to produce higher amounts of some bioactive products. 相似文献