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121.
Schönherr J Fernández V Schreiber L 《Journal of agricultural and food chemistry》2005,53(11):4484-4492
Time courses of cuticular penetration of FeCl3 and Fe(III) complexes of citric acid, EDTA, EDDHA (Sequestrene 138Fe), imidodisuccinic acid (IDHA), and ligninsulfonic acid (Natrel) were studied using astomatous cuticular membranes (CMs) isolated from Populus x canescens leaves. At 100% relative humidity, the Fe(III) chelates disappeared exponentially with time from the surface of the CMs; that is, penetration was a first-order process that can be described using rate constants or half-times of penetration (t(1/2)). Half-times ranged from 20 to 30 h. At 90% humidity, penetration rates were insignificant with the exception of Natrel, for which t(1/2) amounted to 58 h. Rate constants were independent of temperature (15, 25, and 35 degrees C). Permeability decreased with increasing Fe chelate concentration (IDHA and EDTA). At 100% humidity, half-times measured with FeIDHA were 11 h (2 mmol L(-1)), 17 h (10 mmol L(-1)) and 36 h (20 mmol L(-1)), respectively. In the presence of FeEDTA, penetration of CaCl2 was slowed greatly. Half-times for penetration of CaCl2, which were 1.9 h in the absence of FeEDTA, rose to 3.12 h in the presence of an equimolar concentration of EDTA and 13.3 h when the FeEDTA concentration was doubled. Hence, Fe chelates reduced permeability of CMs to CaCl2 and to the Fe chelates themselves. It is suggested that Fe chelates reduced the size of aqueous pores. This view is supported by the fact that rate constants for calcium salts were about 5 times higher than for Fe chelates with the same molecular weights. Adding Tween 20 (5 g L(-1)) as a humectant did not increase permeability to FeIDHA at 90% humidity and below, while addition of glycine betaine did. Penetration of FeCl3 applied at 5 g L(-1) (pH 1.5) was not a first order process as rate constants decreased rapidly with time. Only 2% of the dose penetrated during the first 2 h and less than that in the subsequent 8 h. Recovery was only 70%. This was attributed to the formation of insoluble Fe hydroxide precipitates on CMs. These results explain why in the past foliar application of Fe compounds had limited success. Inorganic Fe salts are instable and phytotoxic because of low pH, while Fe chelates penetrate slowly and 100% humidity is required for significant penetration rates. Concentrations as low as reasonably possible should be used. These physical facts are expected to apply to stomatous leaf surfaces as well, but absolute rates probably depend on leaf age and plant species. High humidity in stagnant air layers may favor penetration rates across stomatous leaf surfaces when humidity in bulk air is below 100%. 相似文献
122.
123.
Summary Dominant genes An
1 for pink flower colour and Br
1 and Br
2 controlling branching of the canes in Rubus coreanus are described. In an F1 progeny and in first backcrosses to red raspberry, some seedlings inherited the ability of R. coreanus to form up to three accessory buds per node. Polygenic systems controlling spine number and spine size are described, number and size being positively correlated. It is postulated that the greater size of spines of h (glabrous-caned) plants is due to linkage of a block of size-controlling genes with the H locus. The greater number of spines of H (hairy-caned) plants is attributed to a pleiotropic effect of the H allele. A new type of dwarf, cauli-flower, which occurred in the F1 and some first backcross progenies, is described. 相似文献
124.
Victoria Patiño-Suárez Dalila Aldana Aranda & Arturo George Zamora 《Aquaculture Research》2004,35(12):1149-1152
This work presents food ingestion and digestibility analysis carried out by means of epifluorescence microscopy of 1‐day‐old Strombus gigas (Linnaeus, 1758) larvae fed five different algal cells: Tetraselmis suecica, T. tetrathele, Chlorella keslleri, Chlorella sp. and Chaetoceros cerastoporum. Absolute ingestion and digestion indices (AII and ADI) were used to compare larval feeding behaviour. Differences in efficiency of ingestion and digestion were observed, according to the diet: the highest AII and ADI were observed with T. suecica and T. tetrathele (>90% and 85–88% respectively). With C. cerastoporum and Chlorella sp. these indices were zero. We confirm the use of Tetraselmis as a suitable diet for S. gigas hatchery. On the contrary, Chlorella sp. and C. cerastoporum are not recommended during the early larval stage, due to their non‐ingestion and digestion. 相似文献
125.
Tzu-Chun Lin Wanchien Victoria Hsiao Shang-Jung Han Shoou-Jeng Joung Jen-Chieh Shiao 《水产资源保护:海洋与淡水生态系统》2021,31(8):2193-2203
- Species identification of sharks under catch or trade regulations is important for law enforcement and species conservation. Rapid detection of Convention on the International Trade in Endangered Species (CITES)-listed species is needed for on-site screening.
- Species-specific primers were designed to target three mitochondrial genes (ND2, COI, and CytB) in both the simplex and multiplex loop-mediated isothermal amplification (LAMP) assay for the pelagic thresher shark (Alopias pelagicus), the bigeye thresher shark (Alopias superciliosus), and the scalloped hammerhead shark (Sphyrna lewini), respectively. Another primer set designed to target S. lewini was used for detection-limit testing of the LAMP assay.
- The refined direct multiplex LAMP was used to detect the three CITES-listed shark species and omitted the lengthy DNA extraction process. A homogenizer was used to release the DNA from the shark tissues, and a simplex or multiplex LAMP reaction was conducted for 30 min in an incubator at 65°C using species-specific primer sets.
- Positive LAMP reactions showed a colour change from pink to yellow, whereas negative reactions showed no colour change. Multiplex LAMP assays were performed using 84 samples, which successfully identified the target and non-target species and provided a fast (<1 h), simple, and reliable method to distinguish three CITES-listed shark species from the other non-target species, for either fresh or dry fin products.
- Results of this study and the method developed will play a critical role in assisting fishery agencies and customs officials in identifying the illegal catch and trade of CITES-listed shark species.
126.
del Valle Juana Cristina Zanazzi Aldo Nahuel Rodriguez Yamila Eliana Haran Nora Selma Laitano María Victoria Mallo Juan Carlos Fernández-Gimenez Analía Verónica 《Aquaculture International》2022,30(4):1645-1658
Aquaculture International - During the early ontogeny, the transition from endogenous (yolk protein) to exogenous feeding (artificial diets) represents a critical period linked to the... 相似文献
127.
Robert M. Boddey Phillip M. Chalk Reynaldo L. Victoria 《Soil biology & biochemistry》1984,16(6):583-588
The contribution of biological N2 fixation to the N nutrition of nodulated soybean was estimated using the 15N isotope dilution technique and a non-nodulating soybean isoline as a non-fixing control plant. The plants were grown in the field in concrete cylinders (60 cm dia) and harvested at seven stages of plant growth. Labelled N was added to the soil either as labelled organic matter before planting or in seven small additions (2kg N ha?1) of (NH4)2SO4 during the growing period.There was good agreement between isotope dilution estimates of nitrogen fixation for the two labelling methods. Acetylene reduction assays on intact root systems greatly underestimated N2 fixing activity. The difference in total N between nodulated and non-nodulated plants generally gave higher estimates compared with the isotope technique. The data indicate that this was because nodulated plants recovered more N from the soil than the non-nodulated plants. After 92 days of growth, the soybean derived approximately 250kg N ha?1 from biological N2 fixation. 相似文献
128.
Robert M. Boddey Phillip M. Chalk Reynaldo Victoria Eiichi Matsui 《Soil biology & biochemistry》1983,15(1):25-32
The contribution of associated biological nitrogen fixation to the nitrogen nutrition of Paspaulum notatum cv. batatais was estimated using the 15N-isotope dilution technique. The plants were grown in the field in concrete cylinders (60 cm dia) filled with soil, to which were added small quantities of 15N-labelled fertilizer at frequent intervals over 12 months. The pensacola cultivar of P. notatum was used as a non-N2-fixing control plant. This was justified by the observation that nitrogenase (intact core C2H2 reduction) activity associated with the pensacola cultivar was consistently much lower than that of the batatais cultivar.At the first harvest, no evidence for N2 fixation associated with the batatais cultivar was obtained, probably because of slow establishment of the N2-fixing association. However, at the subsequent three harvests the batatais cultivar exhibited a lower 15N-enrichment and yielded more N than the pensacola cultivar. These data together suggested that 8–25% of the N in the batatais cultivar originated from N2 fixation.The grass Paspalum maritimum was also included in the experiment and exhibited low nitrogenase activity similar to that of the pensacola cultivar of P. notatum. However, the total N and 15N data of these two grasses were not in good agreement indicating that it is important for the use of the isotope dilution technique that control plants are of very similar physiology and growth habit. 相似文献
129.
A.-H. Fostier M. B. Falótico E. S. B. Ferraz A. C. Tomazelli M. S. M. B. Salomão L. A. Martinelli R. L. Victoria 《Water, air, and soil pollution》2005,166(1-4):381-402
A sampling and analysis program has been completed between 1995 and 1998 in order to determine mercury concentrations in water, sediments, soils and fish in the Piracicaba river basin, one of the most populated and industrialized regions in Brazil. In sediment, the average Hg concentrations varied between 33 ± 17 ng g?1 and 106 ± 78 ng g?1, in samples collected during the rainy and dry season, respectively. The same averages were also found for soil samples (35 ± 14 and 109 ± 61 ng g?1). In water, the total Hg concentration varied between < 1.1 and 24.0 ng L?1. In piscivore fish, up to 943 μ g Hg kg?1 was found. Our results show that all compartments undergo Hg contamination, in view of the levels found in pristine environments. Water contamination seems to be due mainly to diffuse processes of soil erosion and suspension of river bed sediment during the rainy season. Also untreated wastewaters generated by industrial activities and from domestic sewage appear to be potential non-point sources in the most industrialized and populated part of the basin. On the other hand, atmospheric transport of mercury originating from the Campinas Metropolitan Region could be another source of mercury contamination, especially in the basin headwaters. 相似文献
130.