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101.
Pascal Danthu Miarantsoa Rakotobe Pascale Mauclère Hanitra Andrianoelisoa Olivier Behra Voninavoko Rahajanirina Barbara Mathevon Eliane Ralembofetra Philippe Collas de Chatelperron 《Agroforestry Systems》2008,72(2):127-135
Fallow with Psiadia altissima is one of the most common post-‘slash and burn’ vegetation successions described in the evergreen forests of eastern Madagascar.
Some fallows consist of almost pure stands of this species, of which the leaves produce an essential oil offering international
commercial interest. The present research aims to evaluate the production potential of essential oil derived from different
fallows rich in P. altissima. The study has revealed that fallows aged 4 and 6 years since the last crop abandonment produce the most essential oil (around
20 l ha−1), but relative to fallow duration, the youngest fallows (1- or 2-year-old) are the most productive, respectively producing
12 and 6 l ha−1 year−1. Additionally, the trees from the youngest fallows have a substantial capacity for regeneration from coppice shoots, on condition
that the cut is performed well above the root collar. Although farmers earn five times less from harvesting leaves than from
cultivating rice from tavy, the possibility is there for them to complement their income and diversify their production. The overall results show that
sustainable exploitation of fallows of P. altissima is a conceivable option. However, this can only be achieved through an integrated approach that takes into account the environmental
and social constraints associated with the development of this new activity. 相似文献
102.
103.
Julia Siqueira Simoes Eliane Teixeira Mársico César Aquiles Lázaro De La Torre Sérgio Borges Mano Robson Maia Franco Luiz Felipe Lopes Dos Santos 《Journal Of Aquatic Food Product Technology》2019,28(6):703-714
The Malaysian freshwater prawn Macrobrachium rosenbergii was used for nutritional, bacteriological and sensory evaluations. Prawns were refrigerated (0 ± 1°C) and divided into two groups named T1 and T2 corresponding to permeable and impermeable (O2/CO2) packaging, respectively, in order to evaluate their shelf life. The percent composition ensured its high nutritional value, and consumer testing showed that acceptability was close to ideal, with good purchase intent. The type of treatment did not significantly influence the parameters assessed, and the shelf life was established as 150 h. The mesophilic bacteria count was the determining factor for quality assessment. Total volatile basic nitrogen and pH were not good parameters for evaluating quality, whereas the biogenic amines, especially agmatine, appeared to be appropriate quality parameters. 相似文献
104.
Cludio C. Maretti Adriana R. Leo Ana Paula Prates Eliane Simes Ricardo B.A. Silva Ktia T. Ribeiro Leonardo Geluda Manoel S. Sampaio Fernanda F.C. Marques Anna C. Lobo Luís H. de Lima Leonardo M. Pacheco Warwick A. Manfrinato Antnio Q. Lezama Matheus T.P. Couto Paula M. Pereira Moara M. Giasson Paulo H.M. Carneiro Aldízio L. de Oliveira Filho Bernardo F.A. Brito Maurício S. Pompeu Guilherme F. Dutra Mara C. Nottingham Giovanna Palazzi Fabiana O. Hessel Andr L. Lima Bruna De Vita S. Santos Rodrigo Medeiros Marcelo M. Oliveira Mauro O. Pires Mnica Assad Mariana G. Pereira Marcelo R. Kinouchi Rosana J. Subir 《水产资源保护:海洋与淡水生态系统》2019,29(Z2):44-70
- 相似文献
105.
Yan Boucher Maude Perrault-Hébert Richard Fournier Pierre Drapeau Isabelle Auger 《Landscape Ecology》2017,32(2):361-375
Context
Although logging has affected circumboreal forest dynamics for nearly a century, very few studies have reconstructed its influence on landscape structure at the subcontinental scale.Objectives
This study aims to document spatiotemporal patterns of logging and fire since the introduction of logging in the early twentieth-century, and to evaluate the effects of these disturbances on landscape structure.Methods
We used historical (1940–2009) logging and fire maps to document disturbance patterns across a 195,000-km2 boreal forest landscape of eastern Canada. We produced multitemporal (1970s–2010s) mosaics providing land cover status using Landsat imagery.Results
Logging significantly increased the rate of disturbance (+74 %) in the study area. The area affected by logging increased linearly with time resulting in a significant rejuvenation of the landscape along the harvesting pattern (south–north progression). From 1940 to 2009, fire was the dominant disturbance and showed a more random spatial distribution than logging. The recent increase of fire influence and the expansion of the proportion of area classified as unproductive terrestrial land suggest that regeneration failures occurred.Conclusions
This study reveals how logging has modified the disturbances dynamics, following the progression of the logging frontier. Future management practices should aim for a dispersed spatial distribution of harvests to generate landscape structures that are closer to natural conditions, in line with ecosystem-based management. The challenges of defining sustainable practices will remain complex with the predicted increase in fire frequency, since this factor, in combination with logging, can alter both the structure and potentially the resilience of boreal forest.106.
Coffee flavor is the product of a complex chain of chemical transformations. The green bean has only a faint odor that is not at all reminiscent of coffee aroma. It contains, however, all of the necessary precursors to generate the unmistakable coffee flavor during roasting. The levels and biochemical status of these precursors may vary in relation to genetic traits, environmental factors, maturation level, postharvest treatment, and storage. To improve our understanding of coffee flavor generation, the sensory and biochemical impact of maturation was assessed. Maturation clearly favored the development of high-quality flavor in the coffee brew. A specific subclass of green coffee beans, however, generated high-quality coffee flavor irrespective of maturation. Biochemical aspects were examined using a dynamic system: immature and mature green coffee suspensions were incubated under air or argon. On the analytical side, a specific pool of flavor precursors was monitored: chlorogenic acids, green coffee proteins, and free amino acids. A link between maturation, the redox behavior of green coffee suspensions, and their sensory scores was identified. Compared to ripe beans, unripe beans were found to be more sensitive to oxidation of chlorogenic acids. Aerobic incubation also triggered the fragmentation or digestion of the 11S seed storage protein and the release of free amino acids. 相似文献
107.
Amanda Oliveira Magalhães Eliane Teixeira Mársico Manoel Soares Soares Júnior Márcio Caliari 《Journal Of Aquatic Food Product Technology》2020,29(7):661-670
ABSTRACT This work evaluated the technological, bacteriological, and sensorial quality of cookies produced with increasing levels (0%, 10%, 20%, 30%, and 40%) of mechanically separated meat flour from tilapia (MSMF) to replace rice flour (RF) in order to identify the optimal level without compromising the overall quality of the product. The cookies were analyzed for expansion index (EI), specific volume (SV), hardness, color, water activity (aw ), coagulase-positive staphylococci, coliforms at 45°C, Salmonella spp., and sensory acceptance. The inclusion of MSMF affected (P < .05) some characteristics such as EI, SV, aw , hardness, and color (L*, a*, b*), but all formulations met the legal bacteriological standards. Cookies with 20% substitution of RF by MSMF presented 58.82% carbohydrates, 18.53% proteins, and 11.31% lipids, and was the most accepted (P < .05); 51% of consumers rated it with a score of six or higher (above I liked slightly). It is concluded that the substitution of 20% of RF by MSMF can be used for nutritional enrichment of widely consumed conventional products. 相似文献
108.
David Roy Jean-Philippe Auger Mariela Segura Nahuel Fittipaldi Daisuke Takamatsu Masatoshi Okura Marcelo Gottschalk 《Canadian journal of veterinary research》2015,79(2):141-146
Streptococcus suis is an important swine pathogen and a zoonotic agent causing meningitis and septicemia. Although serotype 2 is the most virulent type, serotype 14 is emerging, and understanding of its pathogenesis is limited. To study the role of the capsular polysaccharide (CPS) of serotype 14 as a virulence factor, we constructed knockout mutants devoid of either cps14B, a highly conserved regulatory gene, or neu14C, a gene coding for uridine diphospho-N-acetylglucosamine 2-epimerase, which is involved in sialic acid synthesis. The mutants showed total loss of the CPS with coagglutination assays and electron microscopy. Phagocytosis assays showed high susceptibility of mutant Δcps14B. An in vivo murine model was used to demonstrate attenuated virulence of this non-encapsulated mutant. Despite the difference in the CPS composition of different serotypes, this study has demonstrated for the first time that the CPS of a serotype other than 2 is also an important antiphagocytic factor and a critical virulence factor. 相似文献
109.
Schaffartzik A Marti E Torsteinsdottir S Mellor PS Crameri R Rhyner C 《Veterinary immunology and immunopathology》2011,139(2-4):200-209
Salivary gland proteins of Culicoides spp. have been suggested to be among the main allergens inducing IgE-mediated insect bite hypersensitivity (IBH), an allergic dermatitis of the horse. The aim of our study was to identify, produce and characterize IgE-binding salivary gland proteins of Culicoides nubeculosus relevant for IBH by phage surface display technology. A cDNA library constructed with mRNA derived from C. nubeculosus salivary glands was displayed on the surface of filamentous phage M13 and enriched for clones binding serum IgE of IBH-affected horses. Ten cDNA inserts encoding putative salivary gland allergens were isolated and termed Cul n 2 to Cul n 11. However, nine cDNA sequences coded for truncated proteins as determined by database searches. The cDNA sequences were amplified by PCR, subcloned into high level expression vectors and expressed as hexahistidine-tagged fusion proteins in Escherichia coli. Preliminary ELISA results obtained with these fusions confirmed the specific binding to serum IgE of affected horses. Therefore, the putative complete open reading frames derived from BLAST analyses were isolated by RACE-PCR and subcloned into expression vectors. The full length proteins expressed in Escherichia coli showed molecular masses in the range of 15.5-68.7 kDa in SDS-PAGE in good agreement with the masses calculated from the predicted protein sequences. Western blot analyses of all recombinant allergens with a serum pool of IBH-affected horses showed their ability to specifically bind serum IgE of sensitized horses, and ELISA determinations yielded individual horse recognition patterns with a frequency of sensitization ranging from 13 to 57%, depending on the allergen tested. The in vivo relevance of eight of the recombinant allergens was demonstrated in intradermal skin testing. For the two characterized allergens Cul n 6 and Cul n 11, sensitized horses were not available for intradermal tests. Control horses without clinical signs of IBH did not develop any relevant immediate hypersensitivity reactions to the recombinant allergens. The major contribution of this study was to provide a repertoire of recombinant salivary gland allergens repertoire from C. nubeculosus potentially involved in the pathogenesis of IBH as a starting basis for the development of a component-resolved serologic diagnosis of IBH and, perhaps, for the development of single horse tailored specific immunotherapy depending on their component-resolved sensitization patterns. 相似文献
110.