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排序方式: 共有127条查询结果,搜索用时 15 毫秒
71.
72.
In this work we studied an artisanal fishery targeting mainly soles (Solea senegalensis and Solea solea) and cuttlefish (Sepia officinalis) with trammel nets. Catches of target species, bycatches and discards were studied from October 2004 until August 2005 in the west coast of Portugal. A total of 37 sampling surveys onboard commercial fishing vessels were conducted. The number and weight of individuals of all species caught were registered, as well as the amount discarded and retained by fishermen. A total of 112 species were identified: Scomber japonicus, Chelidonichthys obscura and Callioynimus lyra were the most discarded fishes, corresponding to 28% in weight and 36% in number of discards. Discards represented 22%, in weight, of the total catches, while the amount retained by fishermen for consumption or direct selling was 12%, also in weight. The overall estimate of the annual discards value due to this fishery was ca. 170 tonnes, comprising near 45 fishing vessels. Inconsistencies between the catches recorded onboard and the official landings were detected for the main target species. Some bycatches of species under recovery plans were also found. 相似文献
73.
74.
Milella L Caruso M Galgano F Favati F Padula MC Martelli G 《Journal of agricultural and food chemistry》2011,59(10):5293-5298
Thirteen cultivars and two hybrids of Clementine fruits (Citrus clementina Hort. Ex. Tan) cultivated in Italy were characterized according to pH, titratable acidity, total soluble solids, total polyphenols, carotenoids, vitamin C, hesperidin, rutin, narirutin and naringin and radical scavenging activity. The presence of rutin in Clementine fruit juice is reported for the first time here. The results indicated that all chemical parameters statistically differentiated each cultivar (P < 0.001). In particular, principal component analysis showed a clear discrimination of five cultivars from all the other varieties based on vitamin C and total polyphenols for the Caffin cultivar, which showed also the highest antioxidant activity; narirutin for the Etna hybrid cultivar; hesperidin, rutin and total soluble solids for the SRA 89 cultivar; and naringin, hesperidin and rutin for the Esbal cultivar. Moreover, the Mandalate hybrid cultivar showed the lowest antioxidant activity as well as vitamin C and total polyphenols content, while titratable acidity and naringin level were the highest. The antioxidant activity assessed in all the fruits was closely correlated with vitamin C and total polyphenols content, rather than with the flavonoid compounds. 相似文献
75.
Daniela Sgarbi Cocenza Mariana A. de Moraes Marisa M. Beppu Leonardo Fernandes Fraceto 《Water, air, and soil pollution》2012,223(6):3093-3104
The use of membranes prepared with alginate and chitosan to adsorb paraquat aqueous solution was evaluated as a potential alternative technique for remediation of contaminated water. Production of bilayer membranes was based on the electrostatic interaction between alginate (a polyanion) and chitosan (a polycation). Herbicide adsorption experiments were performed using three different membranes, consisting of pure alginate, pure chitosan, and a chitosan/alginate bilayer. Adsorption was characterized using the Langmuir and Freundlich isotherm models, as well as by applying pseudo-first order and pseudo-second order kinetic models. The potential use of the membranes in environmental applications was evaluated using water collected from the Sorocabinha River in S?o Paulo State, Brazil. The results indicated that interactions between the membranes and the herbicide were strongly related to the type of biopolymer and the physical?Cchemical characteristics of the herbicide. 相似文献
76.
77.
The extraction, fractionation and HIV-1 inhibition potential of polysaccharides extracted from three species of marine sponges, Erylus discophorus, Cliona celata and Stelletta sp., collected in the Northeastern Atlantic, is presented in this work. The anti-HIV activity of 23 polysaccharide pellets and three crude extracts was tested. Crude extracts prepared from Erylus discophorus specimens were all highly active against HIV-1 (90 to 95% inhibition). Cliona celata pellets showed low polysaccharide content (bellow 38.5%) and almost no anti-HIV activity (<10% inhibition). Stelletta sp. pellets, although quite rich in polysaccharide (up to 97.3%), showed only modest bioactivity (<36% HIV-1 inhibition). Erylus discophorus pellets were among the richest in terms of polysaccharide content (up to 98%) and the most active against HIV-1 (up to 95% inhibition). Chromatographic fractionation of the polysaccharide pellet obtained from a specimen of Erylus discophorus (B161) yielded only modestly active fractions. However, we could infer that the active molecule is most probably a high molecular weight sulfated polysaccharide (>2000 kDa), whose mechanism is possibly preventing viral attachment and entry (fusion inhibitor). 相似文献
78.
Leticia Andrea Fernández Pablo Zalba Marisa Anahí Gómez Marcelo Antonio Sagardoy 《Biology and Fertility of Soils》2007,43(6):805-809
The efficiency of 13 phosphate-solubilizing bacteria (PSB; four Burkholderia sp., five Enterobacter sp., and four Bradyrhizobium sp.) was assessed in a soil plate assay by evaluating soil phosphorus (P) availability. A commercial argentine strain, Pseudomonas
fluorescens, was used for comparing solubilizing activity. Burkholderia sp. PER2F, Enterobacter sp. PER3G, and Bradyrhizobium sp. PER2H strains solubilized the largest quantities of P in the soil plate assay after 60 days as compared with the other
strains, including the commercial one. The effect of PSB inoculation on growth and nutrient uptake of soybean plants was also
studied under greenhouse conditions. Plants inoculated with Burkholderia sp. PER2F had the highest aerial height and showed an appropriate N/P ratio. However, none of the PSB increased P uptake
by plants. This suggests that PSB inoculation does not necessarily improve P nutrition in soybean, nor was there any relationship
between P availability in the soil plate assay and P content in the soybean shoot in the greenhouse. We concluded that the
selection of efficient PSB strains as possible inoculation tools for P-deficient soils should focus on the integral interpretation
of soil assays, greenhouse experiments, and field trials. 相似文献
79.
Marques C Ferreira M Gomes JF Leitão N Costa M Serra P Correia JH Pomba CF 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2011,40(2):185-187
Background: The A, B, and AB feline blood types are recognized worldwide and their frequencies vary geographically and among breeds. Frequencies of feline blood types have been reported previously from northern Portugal; however, they are unknown in other parts of the country. Objectives: This 13‐year retrospective study was undertaken to determine the frequency of feline blood types in domestic shorthair (DSH) cats from the Lisbon area of central Portugal. Methods: Blood samples were obtained at the Veterinary Teaching Hospital of the Technical University of Lisbon and its Veterinary Blood Bank and at several veterinary clinics in the Lisbon area. Blood‐typing was performed by the classical agglutination assay or using a cartridge assay. Results: The study population comprised 515 DSH cats of both sexes and various ages. Frequencies of blood types A, B, and AB were 97.5%, 2.1%, and 0.4%, respectively. Conclusion: As in other parts of the world, this study showed a clear predominance of type‐A cats in the Lisbon area of Portugal. 相似文献
80.
Anabela Marisa Azul Sara Margarida Mendes José Paulo Sousa Helena Freitas 《Agroforestry Systems》2011,82(2):121-138
The impacts of land use on soil biodiversity are still poorly understood, although soil fungi and macrofauna are recognized
to provide benefits to ecosystems. Here, we tested whether land use practices used to control shrub density influences the
fruiting macromycetes (ectomycorrhizal-forming fungi—ECMF—and saprobes) and soil macrofauna diversity and abundance in Montado
ecosystems. To address this influence, we conducted a 2-years’ period monitoring of fungi fruitbodies and macrofauna in sixteen
experimental plots in Montado landscape in southern Portugal. A total of 4,881 frutibodies (57 taxa of ECMF and 64 taxa of
saprobic fungi) and 3,667 soil invertebrates (73 species and morphospecies) were monitored in the experimental plots. There
was greater losses in sporocarps production and taxa composition, particularly the ECMF, in plots where shrub density was
controlled by permanent grazing (Ca) or involving cutting practices followed by soil tillage (M), in comparison with cutting
practices with no soil tillage (Cu) and the control (C). The ECMF Laccaria laccata and Xerocomus subtomentosus exhibited a close relation with C and Cu plots while the saprobes, e.g., Entoloma conferendum, were associated to Ca and M plots. Most species associated to Cu plots were present in C plots during the 2 years, but not
in Cu after the cutting practices (in the second year of sampling). Regarding soil macrofauna, higher values of taxa and species
richness were observed in C and Cu plots in the first year of sampling. The ant species Aphaenogaster senilis and several Staphylinid morphospecies exhibited a close relation with M plots, whilst most spider families were directly
associated to C and Cu plots. After the shrub cutting practices, higher values of taxa and species richness of soil macrofauna
were observed in M and Ca plots; the presence of species with a high competitive ability to colonize disturbed areas faster
might explain the results. Contrary to the frutibodies production and diversity, species richness and abundance within soil
macrofauna were identical between Cu and C in 2004. Thus, fruiting macromycetes and soil macrofauna diversity and abundance
in Montado’s, appear highly sensitive to land use and somewhat reflected a trend of severity to the current shrub management
practices. 相似文献