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排序方式: 共有439条查询结果,搜索用时 15 毫秒
431.
Esmeralda Chamorro Legarda Mateus Aranha Martins Patriula Kaliana Moreira Pereira Ramon Felipe Siqueira Carneiro Isabela Claudiana Pinheiro Walter Quadros Seiffert Claudia Machado Marco Antonio de Lorenzo Felipe do Nascimento Vieira 《Aquaculture Research》2020,51(9):3571-3581
This work compared the effects of different densities of Mugil curema integrated in the rearing of Litopenaeus vannamei in a biofloc system on the yield and ecological performance of the system. For that, an experiment lasting 55 days was conducted. Four groups were evaluated as follows: (a) T0: shrimp reared without mullet, (b) T10: shrimp reared with 22 fish per tank, (c) T20: shrimp reared with 43 fish per tank, and (d) T30: shrimp reared with 65 fish per tank, each treatment with four replicates. The sludge:biomass ratio was higher in the T0 treatment, while the T10–T20 treatments were more efficient, producing more biomass and less sludge. The use of water was 17% more efficient in all treatments with mullet. Mullet survival was higher in the T10 and T20 treatments (mean: 84 ± 8%) than in the T30 (61 ± 5%) treatment. The fish final biomass and yield limits of the system were 0.37 kg and 3.7 kg/m3 respectively. Finally, there was no increase in the total nitrogen output of the system up to the T10 density. In conclusion, it is possible to integrate mullet up to 3.7 kg/m3, increasing the yield in 20% and decreasing water use. 相似文献
432.
Step-heating analyses for Mid-Atlantic Ridge glass samples show that maximum 40Ar/36Ar values correlate with 206,207,208Pb/204Pb. These correlations hold for the whole Atlantic Ocean and therefore are unlikely to result from shallow-level contamination processes. Instead, they are taken as mixing hyperbolae between the degassed-depleted upper mantle and a recycled component characterized by high 206Pb/204Pb ratios (19 to 21) and low 40Ar/36Ar ratios (300 to 1000). These relations imply that argon may also be a tracer of mantle recycling. 相似文献
433.
Physiological responses of reared sea bream (Sparus aurata Linnaeus, 1758) to an Amyloodinium ocellatum outbreak 下载免费PDF全文
M Moreira D Schrama F Soares T Wulff P Pousão‐Ferreira P Rodrigues 《Journal of fish diseases》2017,40(11):1545-1560
Amyloodiniosis represents a major bottleneck for semi‐intensive aquaculture production in Southern Europe, causing extremely high mortalities. Amyloodinium ocellatum is a parasitic dinoflagellate that can infest almost all fish, crustacean and bivalves that live within its ecological range. Fish mortalities are usually attributed to anoxia, associated with serious gill hyperplasia, inflammation, haemorrhage and necrosis in heavy infestations; or with osmoregulatory impairment and secondary microbial infections due to severe epithelial damage in mild infestation. However, physiological information about the host responses to A. ocellatum infestation is scarce. In this work, we analysed the proteome of gilthead sea bream (Sparus aurata) plasma and relate it with haematological and immunological indicators, in order to enlighten the different physiological responses when exposed to an A. ocellatum outbreak. Using 2D‐DIGE, immunological and haematological analysis and in response to the A. ocellatum contamination we have identified several proteins associated with acute‐phase response, inflammation, lipid transport, homoeostasis, and osmoregulation, wound healing, neoplasia and iron transport. Overall, this preliminary study revealed that amyloodiniosis affects some fish functional pathways as revealed by the changes in the plasma proteome of S. aurata, and that the innate immunological system is not activated in the presence of the parasite. 相似文献
434.
E. L. Suhendro H. D. Almeida-Dominguez L. W. Rooney R. D. Waniska R. G. Moreira 《Cereal Chemistry》1998,75(6):854-858
An objective bending technique was developed to measure corn tortilla texture. During the test, tortilla strips were bent to a 40° angle. The bending technique detected differences in uniformity, thickness, and puffing. Thick tortillas required more force to bend and had greater moduli of deformation values than thin tortillas. The bending technique detected changes in tortilla texture during storage and textural differences among commercial corn tortillas purchased at supermarkets. Experimental error of the method was low for both commercial and laboratory-prepared tortillas. Parameters measured by the bending technique were significantly correlated with subjective rollability and flexibility test scores. The bending technique was sensitive to sample characteristics, fast, simple, repeatable, and provided information regarding the relationship between force (stress) and distance, which could be used to determine the linear region of viscoelastic materials. 相似文献
435.
436.
Chaves Fernanda Machado Pavan Isadora Carolina Betim da Silva Luiz Guilherme Salvino de Freitas Lidia Broglio Rostagno Mauricio Ariel Antunes Adriane Elisabete Costa Bezerra Rosângela Maria Neves Simabuco Fernando Moreira 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(1):54-62
Plant Foods for Human Nutrition - Pomegranate (Punica granatum) is known to contain polyphenols with many potential health benefits, including anti-tumoral, anti-inflammatory, and anti-microbial... 相似文献
437.
Maize participatory breeding in Portugal: Comparison of farmer's and breeder's on‐farm selection 下载免费PDF全文
Pedro Mendes‐Moreira Zlatko Satovic João Mendes‐Moreira João Pedro Santos João Pedro Nina Santos Silas Pêgo Maria Carlota Vaz Patto 《Plant Breeding》2017,136(6):861-871
“VASO” is a Portuguese participatory maize breeding project (1984), where several maize landraces such as “Pigarro” have been selected both by a farmer's (phenotypic recurrent selection) and a breeder's approach (S2 lines recurrent selection). The objectives of this study were to determine the phenotypic and genotypic responses to participatory selection using these two different approaches, to clarify to which extent both selection methods preserve genetic diversity, and conclude what is the preferred method to apply in sustainable farming systems. The results, obtained via ANOVA, regression analyses and molecular markers, indicate that for both selection methods, genetic diversity was not significantly reduced, even with the most intensive breeder's selection. Although there were some common outputs, such as the determinated versus indeterminated ears, cob and ear weight ratio per ear and rachis 2, specific phenotypic traits evolved in opposite directions between the two selection approaches. Yield increase was only detected during farmer selection, indicating its interest on PPB. Candidate genes were identified for a few of the traits under selection as potential functional markers in participatory plant breeding. 相似文献
438.
E. L. Suhendro H. D. Almeida-Dominguez L. W. Rooney R. D. Waniska R. G. Moreira 《Cereal Chemistry》1999,76(4):536-540
An objective extensibility test was evaluated to measure texture of corn tortillas. A tortilla strip is pulled apart by a tensile force during the test. Force at 1 mm deformation, force required to rupture the tortilla strip, modulus of deformation, and extensibility distance were correlated to subjective rollability and flexibility scores. Hard, firm tortillas required more force to deform and to rupture and had greater moduli of deformation than soft, flexible tortillas. Tortilla texture was affected by manufacturer of commercial tortillas and by aging. The coefficient of variation ranged from 6.0 to 16.7% for force at 1 mm deformation and work required to rupture, respectively. The extensibility technique is sensitive, fast, simple, and repeatable. 相似文献
439.
Tortilla chips were slow dried after baking and then fried in fresh soybean oil. Control chips were not dried before frying. Final oil content of sun-dried tortilla chips was significantly (P < 0.05) lower than those receiving the control treatment. As a result of drying, the structure of the tortilla chips was tighter before frying but expanded significantly during frying. An attempt was made to produce tortilla chips with the same characteristics of the sun-dried chips using impinging hot-air drying techniques. Results indicated that tortilla chips drying rate was mostly affected by air temperature; texture was crispier at higher air temperatures; shrinkage of the piece was higher at lower convective heat transfer coefficient; and microstructure looked smoother at higher air temperature. 相似文献