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21.
Rudik SK 《Historia medicinae veterinariae》2003,28(2):41-46
The Ukraine is one of the centers of domestication of animals. Many archaeological excavations and chronicles evidence this. The wild horse tarpan was domesticated in Ukraine. There were huge herds of tarpans lived in Ukraine. Tarpans were distinguished for their speed, quality of their hooves (it was very important for the shoeless horses). The last tarpan mare was killed at Ukrainian territory at 1898. In contradistinction to the Eq. Prezewalskii the tarpan was the direct ancestor of the European domesticated horse breeds. 相似文献
22.
Genetic variability of PRRS virus in Austria: consequences for molecular diagnostics and viral quantification 总被引:5,自引:0,他引:5
Porcine reproductive and respiratory syndrome virus is a virus with a relatively high level of sequence variation, especially between the European and the American-type strains. This high degree of sequence variations will influence the accuracy of results obtained by molecular diagnostic methods, especially if mutations are located in the primer or probe binding regions of PCR or real-time PCR based assays. In order to provide the basis for the development of an accurate, region-tailored assay we have analysed samples obtained from several Austrian pig herds using a series of RT-PCR assays. Subsequent sequencing of the PCR products from ORF5 and phylogenetic analysis revealed the occurrence of both the European and the American-type of porcine reproductive and respiratory syndrome virus in Austria. Since vaccination with the American-type vaccine is not authorized in Austria the import of vaccinated animals is the most likely explanation for the occurrence of these strains. The study highlights the importance of a detailed study on the sequence variations occurring in the region of interest before the development of a reliable PCR-based assay. 相似文献
23.
Rosypal AC Hall JE Bakunova S Patrick DA Bakunov S Stephens CE Kumar A Boykin DW Tidwell RR 《Veterinary parasitology》2007,145(3-4):207-216
Canine leishmaniasis caused by Leishmania infantum is enzootic in the North American foxhound population. Currently available chemotherapy for canine leishmaniasis is not completely effective and relapses are common in treated dogs. Pentamidine and related aromatic diamidines possess broad spectrum antiprotozoal activity. The in vitro antileishmanial activities of 35 aromatic cationic molecules were determined, using pentamidine as the reference drug. The compounds were examined for activity against promastigotes of L. infantum isolated from a foxhound from Virginia. The compounds most active against Leishmania parasites were reversed amidines. Compound 9, a reversed amidine, exhibited the highest activity against L. infantum, with a 50% inhibitory concentration (IC(50)) of 0.0042 microM compared with 14.2 microM for pentamidine. Antileishmanial activities of nine compounds were at least 1000-fold higher relative to the reference drug. Results from this study indicate that several pentamidine-related compounds warrant further investigation as possible new agents for the treatment of canine leishmaniasis. 相似文献
24.
Vacek Zdeněk Cukor Jan Vacek Stanislav Linda Rostislav Prokůpková Anna Podrázský Vilém Gallo Josef Vacek Oldřich Šimůnek Václav Drábek Ondřej Hájek Vojtěch Spasić Marko Brichta Jakub 《European Journal of Forest Research》2021,140(5):1243-1266
European Journal of Forest Research - In the time of ongoing climate change and the increasing area of post-mining landscape, the successful afforestation of reclamation sites by suitable adaptive... 相似文献
25.
Stanislav Kucbel Peter Jaloviar Milan Saniga Jaroslav Vencurik Vladimír Klimaš 《European Journal of Forest Research》2010,129(3):249-259
The old-growth forest remnants of Western Carpathians provide a unique possibility to study the disturbance regimes of forest
ecosystems without human influence. This study investigated the gap dynamics in beech-dominated old-growth forest Badínsky
prales in Central Slovakia. Considering the decline of silver fir in last decades, the study analyzed the main characteristics
of disturbance regime with the emphasis on the role of fir. On a 5-ha research plot, the dominant tree species was beech,
the proportion of fir reached about 10%. However, a significantly higher proportion of fir (>30%) was observed in the coarse
woody debris. In total, 45 canopy openings were recorded. Canopy gaps and expanded gaps covered 11.3 and 37.9% of the forest
area, respectively. Despite the highest frequency of small gaps <100 m2, their proportion of the overall gap area reached only 20%, what suggests the important role of intermediate and large gaps
in the gap dynamics as well. The analysis of gapmakers’ crown projections confirmed a rather low contribution of fir (14.6%)
to the gap formation despite its relatively intensive mortality. A high variability of the next generation age between the
gaps (6–44 years) was recorded what suggests a large temporal variation of the disturbance events. The lateral expansion of
adjacent trees was found to be the determining process for the closure of small canopy openings. The intermediate and large
gaps are more likely closed by the height growth of natural regeneration and understory trees that are present on the majority
of the area. 相似文献
26.
Stanislav Vacek Iva Ulbrichová Jiří Remeš Vilém Podrázský Marek Vach 《Scandinavian Journal of Forest Research》2019,34(4):267-281
We studied the effects of magnesium (Mg) NPK fertilizer applied in 2000 to maturing Norway spruce (Picea abies /L./ Karst.) stands with yellowing symptoms and situated on poor acidified soils in the ?umava mountains (the Czech Republic). Long-term defoliation, nutrient content in the foliage and diameter increment were evaluated in three specific variants: yellowing trees, trees without yellowing symptoms and fertilized trees. The results indicate differences in soil characteristics, nutrient content and radial growth with response to climate. Fertilization increased Mg content and base saturation in the soil and decreased the amount of exchangeable aluminum and hydrolytic acidity. Differences were significant especially in magnesium, calcium and phosphorus contents in the foliage of yellowing trees. There was also a significant difference in manganese content; yellowing trees showed deficiency in comparison with both fertilized and unfertilized healthy trees. Two years after the initial fertilization (to present), defoliation and yellowing symptoms in the unfertilized yellowing trees were more pronounced compared to other variants. These symptoms were more influenced by fertilization than foliation. The duration of significant positive effects of fertilization on diameter increment lasted for a shorter time than the effect on foliage. Simultaneously, higher sensitivity to climatic factors was observed in the fertilized trees. 相似文献
27.
Journal of Plant Diseases and Protection - Ethanol extracts of Rosmarinus officinalis, Lavandula angus-tifolia and Ruta graveolens were tested against adults of Acanthoscelides obtectus and... 相似文献
28.
The damage caused by Thrips tabaci to a susceptible hybrid of early white cabbage was studied in field experiments undertaken during 2004 and 2005. The three treatments tested were beds of cabbage mulched with: (1) barley straw, (2) hay, and (3) black polyethylene (PE) sheeting. Bare-soil (un-mulched) beds were used as the control treatment. One early and one late experiment were performed in both years. In the early experiments, the mulches were applied at the start of the experiment, whereas in the late experiments the soil was first covered with black polyethylene for approximately 1 month. In both years, the springs were cold and wet, and so the thrips appeared late and their numbers were low. The highest mean actual weight and trimmed weight were recorded for cabbage grown in 2005 under PE mulch (actual early: 995 g, actual late: 1184 g, trimmed early: 870 g, trimmed late: 1056 g). Year 2004 gave lower values (110g for both variables) under barley straw and hay mulch (165 g and 160 g, respectively). There was no evidence of an allelopathic effect of water extracts of either barley straw or hay. 相似文献
29.
Stanislav Trdan Filip Vučajnk Tanja Bohinc Matej Vidrih 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2019,69(1):89-94
In 2017, we conducted a field experiment to test the influence of a mixture of two plant growth-promoting bacteria (Pseudomonas fluorescens and Azospirillum brasilense) on the yield of three potato varieties. In addition, the influence of the mixture on potato susceptibility to infection by the pseudofungus Phytophthora infestans and fungus Alternaria solani and to attacks by the Colorado potato beetle (Leptinotarsa decemlineata) was investigated. It was the first experiment of its kind in Europe. In the unusually hot and dry year, a positive influence on the yield (17%–31%) was found in all three varieties when the tubers were soaked in the bacterial mixture prior to sowing. We observed no significant differences in potato resilience/susceptibility to harmful organisms among the different treatments (soaked tubers, sprayed tubers, untreated tubers); however, there were significant differences in the productivity between the tuber varieties. The results of our research indicate the bacterial mixture used in this study has a high potential to support satisfactory potato yields under dry conditions and under low levels of infection by foliar fungal diseases and attacks by foliar insects. 相似文献
30.
Stanislav Korenko Emanuel Kula Michal Holec Martin Jarab Veronika Michalkov 《European Journal of Soil Biology》2008,44(5-6):559
We studied the influence of liming with the dolomitic limestone on the epigeic spider community in the birch stand of the Krušné hory Mts. in the Czech Republic. The treatment was carried out with the purpose of reducing the negative effect of anthropogenic air pollution and consequently to increase the ecological stability of the wood stand. Lime treatment in different amounts (6, 3, 1.5 and 0 t ha−1) was applied in August 2003 and for the following three years the spider community was investigated. We compared occurrences of spiders on studied plots with different lime treatment and tested the influence of the environmental factors, altogether with liming, on the spider community. The most significant factor appeared to be the character of habitat and both, hierarchical cluster analysis and canonical correspondence analysis, did not confirm any significant feedback of liming to the spider community in birch stand of the Krušné hory Mts. 相似文献