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41.
de Terra H 《Science (New York, N.Y.)》1956,124(3235):1282-1285
42.
de Terra H 《Science (New York, N.Y.)》1953,118(3077):748-749
43.
Laura Nahuelhual Tomás Vallejos Gonzalo Campos Ximena Vergara Stefan Gelcich Rodrigo Estévez 《Fish and Fisheries》2023,24(3):504-521
Wicked problems are typically social justice and social change problems, complex and messy. They mobilize opposed views about the essential nature of the issues, their relative importance and adequate responses. We assert that illegal fishing in small-scale fisheries (SSF) can be considered a wicked problem and our aim is to test this assertion. We relied on a conceptual framework that defines wicked problems as (1) indefinable and non-generalizable, (2) ambiguously bounded, (3) temporally exacting, (4) repercussive, (5) doubly hermeneutic and (6) morally consequential. We applied a qualitative research approach based on field data comprising three illustrative Chilean SSF, whereas secondary data complemented the analysis. The results demonstrate that illegal fishing fits most of the requirements of a wicked policy problem. It is indefinable and non-generalizable, with different representations and uncertainty about its nature, magnitude and effects. Depictions of the nature of the problem varied from a lack of regulations' legitimacy, to a ‘combat’ to be won. It is ambiguously bounded, caused by interrelated sub-problems (e.g. poverty, access), involving multiple policy sectors, administrative scales and actors. It is also temporally exacting and repercussive as it lacks criteria to prove that a solution has been reached and the implications of alternative solutions (e.g. self-regulation) are unknown. As long as illegal fishing is reframed as a wicked problem, the stakeholders involved can also recognize that there are no perfect solutions and therefore promote a mix of substandard governance approaches. 相似文献
44.
F D Galey R Terra R Walker J Adaska M A Etchebarne B Puschner E Fisher R H Whitlock T Rocke D Willoughby E Tor 《Journal of veterinary diagnostic investigation》2000,12(3):204-209
Four hundred twenty-seven of 441 adult Holstein dairy cattle from a 1,200-cow dairy died over a 1-week period during early spring 1998. Affected animals were from 4 late lactation pens, one of which included the bull string. Signs included weakness, recumbency, watery diarrhea, and death. Eighty animals from the 4 pens were dead approximately 8 hours after the first ill cows were noted. Affected cows would collapse on stimulation and extend all 4 limbs with moderate rigidity. Several lacked lingual tonus and had abdominal breathing patterns. The animals had been fed a load of total mixed ration that included a rotten bale of oat hay containing a dead cat. No common toxicants were identified, and pathologic examination revealed no consistent lesions. Testing of tissue from the cat carcass found in the feed sample using mouse protection bioassay identified the presence of type C botulinum toxin. Samples of feed, tissue from affected animals, cat tissue from feed, milk, and serum were also tested using an enzyme-linked immunosorbent assay (ELISA) specific for type C botulinum. Two samples of rumen contents were tested and found to be positive for botulism by ELISA, and 1 of 3 liver samples had a weak positive finding. No botulinum toxin was found in milk or sera using the ELISA. 相似文献
45.
Marlon Felipe Higuita Palacio Olga I Montoya Clara I Saldamando Erika García-Bonilla Howard Junca Gloria E Cadavid-Restrepo Claudia Ximena Moreno-Herrera 《Journal of insect science (Online)》2021,21(6)
Spodoptera frugiperda is a polyphagous pest of several crops of economic importance. Nowadays, the insect is broadly distributed in America and, recently, in Africa, Asia, and Australia. The species has diverged into corn and rice strains. The role of the gut microbiota in insect physiology is relevant due to its participation in crucial functions. However, knowledge of seasonal variations that alter the gut microbiome in pests is limited. Gut microbiome composition between the dry and rainy seasons was analyzed with cultured and uncultured approaches in S. frugiperda corn strain larvae collected at Northwest Colombia, as seasonal microbiome changes might fluctuate due to environmental changes. On the basis of culture-dependent methods, results show well-defined microbiota with bacterial isolates belonging to Enterococcus, Klebsiella (Enterobacteriales: Enterobacteriaceae), Enterobacter (Enterobacterales: Enterobacteriaceae), and Bacillus (Bacillales: Bacillaceae) genera. The community composition displayed a low bacterial diversity across all samples. The core community detected with uncultured methods was composed of Enterococcus, Erysipelatoclostridium (Erysipelotrichales: Erysipelotrichaceae), Rasltonia (Burkholderiales: Burkholderiaceae), and Rhizobium (Hyphomicrobiales: Rhizobiaceae) genera, and Enterobacteriaceae family members. Significant differences in microbiome diversity were observed between the two seasons. The relative abundance of Erysipelatoclostridium was high in the dry season, while in the phylotype ZOR0006 (Erysipelotrichales: Erysipelotrichaceae) and Tyzzerella (Lachnospirales: Lachnospiraceae) genus, the relative abundance was high in the rainy season. The overall low gut bacterial diversity observed in the S. frugiperda corn strain suggests a strong presence of antagonist activity as a selection factor possibly arising from the host, the dominant bacterial types, or the material ingested. Targeting the stability and predominance of this core microbiome could be an additional alternative to pest control strategies, particularly in this moth. 相似文献
46.
47.
48.
de Terra H 《Science (New York, N.Y.)》1934,80(2081):447-449
49.
Román BS Garrido V Muñoz PM Arribillaga L García B De Andrés X Zabaleta V Mansilla C Farrán I Lasa I De Andrés D Amorena B Lasarte JJ Grilló MJ 《Veterinary research》2012,43(1):31
ABSTRACT: The Extradomain A from fibronectin (EDA) has an immunomodulatory role as fusion protein with viral and tumor antigens, but its effect when administered with bacteria has not been assessed. Here, we investigated the adjuvant effect of EDA in mice immunizations against Salmonella enterica subspecies enterica serovar Enteritidis (Salmonella Enteritidis). Since lipopolysaccharide (LPS) is a major virulence factor and the LPS O-polysaccharide (O-PS) is the immunodominant antigen in serological diagnostic tests, Salmonella mutants lacking O-PS (rough mutants) represent an interesting approach for developing new vaccines and diagnostic tests to differentiate infected and vaccinated animals (DIVA tests). Here, antigenic preparations (hot-saline extracts and formalin-inactivated bacterins) from two Salmonella Enteritidis rough mutants, carrying either intact (SEΔwaaL) or deep-defective (SEΔgal) LPS-Core, were used in combination with EDA. Biotinylated bacterins, in particular SEΔwaaL bacterin, decorated with EDAvidin (EDA and streptavidin fusion protein) improved the protection conferred by hot-saline or bacterins alone and prevented significantly the virulent infection at least to the levels of live attenuated rough mutants. These findings demonstrate the adjuvant effect of EDAvidin when administered with biotinylated bacterins from Salmonella Enteritidis lacking O-PS and the usefulness of BEDA-SEΔwaaL as non-live vaccine in the mouse model. 相似文献
50.
Vernica S. Ciganda María Lpez-Aizpún Miguel A. Repullo Di Wu Jos A. Terra David Elustondo Tim Clough Laura M. Cardenas 《植物养料与土壤学杂志》2019,182(1):40-47
In grassland systems, cattle and sheep urine patches are recognized as nitrous oxide (N2O) emission hot spots due to the high urinary nitrogen (N) concentrations. Hippuric acid (HA) is one of the constituents of ruminant urine that has been reported as a natural inhibitor of soil N2O emissions. The aim of this study was to examine the potential for elevated ruminant urine HA concentrations to reduce N2O emissions, in situ, on an acidic heavy clay soil under poorly drained conditions (WFPS > 85%). A randomized complete block design experiment with three replications and four treatments was conducted using the closed‐static‐flux chamber methodology. The four treatments were applied inside the chambers: control with no artificial urine application (C), control artificial urine (U), and enriched artificial urine with two rates of HA (55.8 and 90 mM, U+HA1, U+HA2). Soil inorganic‐N, soil dissolved organic carbon (DOC), soil pH as well as N2O and methane (CH4) fluxes were monitored over a 79‐d period. Although N2O emissions were not affected by the HA enriched urine treatments, U+HA2 positively affected the retention of N as until day 3, when the soil pH dropped to values < 5. Subsequently, as a consequence of rainfall events and soil acidification, it is likely that leaching or sorption onto clay reduced the efficacy of HA, masking any treatment differential effect on N2O emissions. Moreover, CH4 fluxes as well as DOC results reflected the soil anaerobic conditions which did not favour nitrification processes. Further research is needed to determine the fate of HA into the soil which might clarify the lack of an in situ effect of this compound. 相似文献