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71.
Danielle de Carla Dias Marta Verardino De Stéfani Cláudia Maris Ferreira Fernanda Menezes França Maria José Tavares Ranzani‐Paiva Antenor Aguiar Santos 《Aquaculture Research》2010,41(7):1064-1071
The effects of two probiotics (P1–Lactobacillus acidophilus, Bifidobacterium bifidum and Enterococcus faecium and P2–Bacillus subtilis) supplemented to commercial feed (40% crude protein) on the haematological and immunological parameters of the bullfrog Lithobates catesbeianus were studied. Two doses of each probiotic (5 and 10 g kg?1 of food) were added to the diets and fed to frogs, totalling five treatments over 112 days. Haematological analyses consisted of total and differential leucocyte counts, erythrocyte and thrombocyte counts, haematocrit, haemoglobin levels and RBC indices (mean corpuscular volume, mean corpuscular haemoglobin – and mean corpuscular haemoglobin concentration) and the immunological parameters included phagocytic capacity and phagocytic index of peritoneal phagocytes. The results showed that the probiotics did not significantly influence any of the haematological parameters measured. However, immunological assays showed that the probiotics had an immunostimulating effect. The greatest effects were seen with probiotic P1 fed at a dose of 10 g kg?1 of diet and probiotic P2 fed at 5 g kg?1 of diet. 相似文献
72.
73.
Maximum daily trunk shrinkage and stem water potential reference equations for irrigation scheduling of lemon trees 总被引:1,自引:2,他引:1
Maria Fernanda Ortuño Juan José Brito Yelitza García-Orellana Wenceslao Conejero Arturo Torrecillas 《Irrigation Science》2009,27(2):121-127
Measurements of midday stem water potential (ψstem) and maximum daily trunk shrinkage (MDS) were done over a 3-year period in adult Fino lemon trees (Citrus
limon (L.) Burm. fil.) grafted on sour orange (C. aurantium L.) rootstocks. Plants were irrigated daily above their water requirements in order to obtain non-limiting soil water conditions.
The results indicated that reference equations can be obtained for MDS and ψstem by pooling data across several seasons using crop reference evapotranspiration (ETo), daily mean vapor pressure deficit (VPDm) and mean daily air temperature (T
m) in the case of MDS, and ETo in the case of ψstem. The best predictor of MDS under non-limiting soil water conditions was T
m, suggesting that MDS reference values can be obtained by means of easy and cheap measurements. MDS and ψstem values were not influenced significantly by yield or crop load variations between years. A negative linear relationship between
MDS and ψstem was found, pointing to an unchanging radial hydraulic conductivity in the bark tissues and suggesting that the MDS is controlled
by water potential. 相似文献
74.
Francis C. Ogbonnaya Gouyou Ye Richard Trethowan Fernanda Dreccer Douglas Lush John Shepperd Maarten van Ginkel 《Euphytica》2007,157(3):321-336
Wheat is one of the major food crops in the world. It is Australia’s largest crop and most important agricultural commodity.
In Australia the crop is grown under rainfed conditions with inherently important regional environmental differences; wheat
growing areas are characterized by winter dominant rainfall in southern and western Australia and summer rainfall in northern
Australia. Maximizing yield potential across these diverse regions is dependent upon managing, either genetically or agronomically,
those factors in the environment that limit yield. The potential of synthetic backcross lines (SBLs) to increase yield in
the diverse agroecological zones of Australia was investigated. Significant yield advantages were found for many of the SBLs
across diverse environments. Depending on the environment, the yield of the SBLs ranged from 8% to 30% higher than the best
local check in Australia. Apart from adaptation to semiarid water stressed conditions, some SBLs were also found to be significantly
higher yielding under more optimal (irrigated) conditions. The four testing environments were classified into two groups,
with the northern and southern environments being in separate groups. An elite group of SBLs was identified that exhibited
broad adaptation across all diverse Australian environments included in this study. Other SBLs showed specific adaptation
to either northern or southern Australia. This study showed that SBLs are likely to provide breeders with the opportunity
to significantly improve wheat yield beyond what was previously possible in a number of diverse production environments. 相似文献
75.
Erlon L. Pereira Alisson C. Borges Fernanda F. Heleno Tiago H. C. Costa Ann H. Mounteer 《Water, air, and soil pollution》2017,228(6):213
Economic and environmental stimuli for biodiesel production have also increased production of glycerol, a byproduct present in biodiesel industry wastewater (BIW). The objective of the present study was to analyze which factors influenced glycerol biodegradation in anaerobic sequencing batch reactors (AnSBR) in the attempt to optimize chemical oxygen demand (COD) removal efficiency. Six factors were analyzed: pH, temperature, mixing speed, influent COD, inoculum mass, and reaction time. The results indicated that mixing speed, temperature, mass of inoculum, and reaction time had direct influence on COD removal efficiency in BIW. The reactor used in the experiments operated with efficiencies and applied loads above those mentioned in the literature. The mathematical model generated in this study can be used for estimating efficiency, process control and scale up of AnSBR. 相似文献
76.
Barbarella Matos de Macchi Farlen José Bebber Miranda Fernanda Silva de Souza Eulógio Carlos Queiroz de Carvalho Ant?nio Peixoto Albernaz José Luiz Martins do Nascimento Renato Augusto DaMatta 《Veterinary research》2013,44(1):8
Malaria is a serious infectious disease caused by parasites of the Plasmodium genus that affect different vertebrate hosts. Severe malaria leads to host death and involves different pathophysiological phenomena such as anemia, thrombocytopenia and inflammation. Nitric oxide (NO) is an important effector molecule in this disease, but little is known about its role in avian malaria models. Plasmodium gallinaceum- infected chickens were treated with aminoguanidine (AG), an inhibitor of inducible nitric oxide synthase, to observe the role of NO in the pathogenesis of this avian model. AG increased the survival of chickens, but also induced higher parasitemia. Treated chickens demonstrated reduced anemia and thrombocytopenia. Moreover, erythrocytes at different stages of maturation, heterophils, monocytes and thrombocytes were infected by Plasmodium gallinaceum and animals presented a generalized leucopenia. Activated leukocytes and thrombocytes with elongated double nuclei were observed in chickens with higher parasitemia; however, eosinophils were not involved in the infection. AG reduced levels of hemozoin in the spleen and liver, indicating lower inflammation. Taken together, the results suggest that AG reduced anemia, thrombocytopenia and inflammation, explaining the greater survival rate of the treated chickens. 相似文献
77.
Rosa RM Melecchi MI da Costa Halmenschlager R Abad FC Simoni CR Caramão EB Henriques JA Saffi J de Paula Ramos AL 《Journal of agricultural and food chemistry》2006,54(19):7324-7330
The genus Hibiscus thrives in a variety of climates and produces a diversity of natural compounds with bioactive properties. We have studied the chemical composition and the in vivo antioxidant properties of Hibiscus tiliaceus L. methanolic flower extract, as well as its mutagenic/antimutagenic effects. Vitamin E and some stigmasterol derivatives that might confer an antioxidant effect to the extract were present. Treatment with this extract protected several Saccharomyces cerevisiae strains defective in antioxidant defenses against H2O2 and t-BOOH cytotoxicities, showing a clear antioxidant activity. The effect is the same for all strains used, independent of the antioxidant defense disrupted, suggesting that protection may be due to molecules that act as versatile and wide spectrum nonenzymatic antioxidants, such as vitamins or phytosterols. The extract was not mutagenic in either Salmonella typhimurium or S. cerevisiae and showed a significant antimutagenic action against oxidative mutagens in S. cerevisiae. 相似文献
78.
Pereira FM Rosa E Fahey JW Stephenson KK Carvalho R Aires A 《Journal of agricultural and food chemistry》2002,50(21):6239-6244
Broccoli inflorescences have been recognized as components of healthy diets on the basis of their high content of fiber, vitamin C, carotenoids, and glucosinolates/isothiocyanates. Broccoli sprouts have been recently shown to have high levels of glucoraphanin (4-methylsulfinylbutyl glucosinolate), the precursor of the chemoprotective isothiocyanate, sulforaphane. This study evaluated the effects of temperature and developmental stage on the glucosinolate content of broccoli sprouts. Seedlings cultivated using a 30/15 degrees C (day/night) temperature regime had significantly higher glucosinolate levels (measured at six consecutive days postemergence) than did sprouts cultivated at lower temperatures (22/15 and 18/12 degrees C; p < 0.001). Both higher (33.1 degrees C) and lower (11.3 degrees C) constant temperatures induced higher glucosinolate levels in sprouts grown to a uniform size. Glucosinolate levels were highest in cotyledons and lowest in roots of sprouts dissected both early and late in the 11 day developmental span investigated. Nongerminated seeds have the highest glucosinolate levels and concordantly greater induction of mammalian phase 2 detoxication enzymes. Levels decline as sprouts germinate and develop, with consistently higher glucosinolate content in younger developmental stages, independent of the temperature regime. Temperature stress or its associated developmental anomalies induce higher glucosinolate levels, specific elevations in glucoraphanin content, and parallel induction of phase 2 chemoprotective enzymes. 相似文献
79.
Lorena M. Lagos Oscar U. Navarrete Fumito Maruyama David E. Crowley Fernanda P. Cid María L. Mora Milko A. Jorquera 《Biology and Fertility of Soils》2014,50(8):1253-1266
Management of soils to facilitate plant beneficial microbial interactions requires basic knowledge of the species composition and microbial community structures in the plant rhizosphere. Here, we examined composition of bacterial communities associated with rhizosphere microsites located at the root tips and mature root zones of Lolium perenne when grown in Chilean ash-derived volcanic soils (Andisols: Freire and Piedras Negras soil series). Community structures were analyzed by pyrosequencing of 16S ribosomal RNA (rRNA) genes followed by in silico analysis for phylogenetic assignments (MOTHUR and Visualization tool for Taxonomic Compositions of Microbial Community (VITCOMIC)). Analysis of the community structure revealed significant differences in community structures in relation to the soil series, which differed particularly in the relative abundance of Cyanobacteria and Firmicutes. However, no significant differences were observed with respect to root microsite location in the same Andisol series. Predominant taxa included members of the Proteobacteria, Actinobacteria, and Acidobacteria. Analysis by VITCOMIC showed that dominant bacterial groups comprised only 5 to 10 % of the total bacterial community and the remaining majority of bacteria included low-abundant taxa (Fusobacteria, Thermotogae, Lentisphaerae, Tenericutes, Deferribacteres Spirochaetes, Planctomycetes, Thermotogae, and Deinococcus-Thermus), most of which have not been previously reported or associated with the plant rhizosphere according to GenBank database. The results indicate that most of bacteria in the Chilean Andisols have not been described to the rhizosphere plants and their functional traits are still largely unknown. 相似文献
80.
Henrique M. Ribeiro David Fangueiro Fátima Alves Ernesto Vasconcelos João Coutinho Roland Bol Fernanda Cabral 《植物养料与土壤学杂志》2010,173(1):39-45
The dynamics of C mineralization in an organically managed Cambic Arenosol amended with hen manure, a stabilized compost (compost), and three different combinations of both fertilizers (varying from a 1:100 to a 1:10 ratio) were studied during an incubation experiment to estimate the potential of such combinations to preserve/restore soil C content relative to single applications. A strong increase of the CO2‐C emissions relative to the unamended soil (control) was observed after soil application of all five organic‐fertilizer treatments. A significantly higher amount of applied C was lost in hen‐manure treatment (648 mg CO2‐C [g C applied]–1) when compared to compost (159 mg CO2‐C [g C applied]–1) or to the three combined treatments (176–195 mg CO2‐C [g C applied]–1). The first‐order exponential model and the double exponential model were used to fit the C‐mineralization data in the treatments considered. Results showed that mixing “small” amounts of hen manure with compost did not affect the total amount of potentially mineralizable C, but significantly increased the mineralization rate constant. Clearly, combinations of both fertilizers promoted an initial faster mineralization of the organic matter, and consequently a faster release of nutrients, without affecting the total amount of C sequestered in soil. 相似文献