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31.
Mapping Spatial Patterns with Morphological Image Processing 总被引:4,自引:3,他引:1
Peter Vogt Kurt H. Riitters Christine Estreguil Jacek Kozak Timothy G. Wade James D. Wickham 《Landscape Ecology》2007,22(2):171-177
We use morphological image processing for classifying spatial patterns at the pixel level on binary land-cover maps. Land-cover
pattern is classified as ‘perforated,’ ‘edge,’ ‘patch,’ and ‘core’ with higher spatial precision and thematic accuracy compared
to a previous approach based on image convolution, while retaining the capability to label these features at the pixel level
for any scale of observation. The implementation of morphological image processing is explained and then demonstrated, with
comparisons to results from image convolution, for a forest map of the Val Grande National Park in North Italy. 相似文献
32.
Aboveground net primary production (ANPP) and N and P use patterns were determined for western larch (Larix occidentalis Nutt.), a deciduous conifer, and lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.), an evergreen conifer, in the Cascade Mountains of Washington, USA. Western larch and lodgepole pine retranslocated 87 and 66% of foliage N and 66 and 78% of foliage P, respectively. At the stand level, N use efficiency of western larch was greater than that of lodgepole pine, whereas P use efficiency of lodgepole pine was greater than that of western larch. Western larch and lodgepole pine were comparable in ANPP and production efficiency (ANPP/foliage mass) if needle longevity is considered. The similarity in ANPP of the evergreen lodgepole pine and the deciduous western larch may be related in part to the lower initial construction cost of the foliage, and the efficient use of nitrogen by western larch. 相似文献
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Stalder HP Meier P Pfaffen G Wageck-Canal C Rüfenacht J Schaller P Bachofen C Marti S Vogt HR Peterhans E 《Preventive veterinary medicine》2005,72(1-2):37-41; discussion 215-9
We have genetically analyzed ruminant pestiviruses. All >150 bovine viral diarrhea (BVD) viruses isolated from cattle in Switzerland belonged to genotype 1, with subgenogroups e, h, k and b found in decreasing frequency. To date, representatives of subgenogroup k have been detected in Switzerland only. Despite serological evidence of Border disease in sheep, only few Border disease viruses have been isolated, all of which belong to the novel group 3. Serological evidence suggested that pestivirus infections may occur also in wild ruminants in Switzerland but no isolates are available for analysis. In addition, we describe two pestiviruses, one a cell culture contaminant and the other isolated from a buffalo, that cluster with a recently proposed novel pestivirus species. 相似文献
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Zhipeng Zhou Guoliang Li Siyu Tan Dongdong Li Thea Mi Weiß Xiangfeng Wang Shaojiang Chen Tobias Würschum Wenxin Liu 《Plant Breeding》2020,139(3):562-574
Grain yield and its component traits are essential targets in maize breeding. These traits are genetically complex and controlled by a large number of quantitative trait loci (QTL). The aim of this study was to compile reported QTL and major genes for grain yield and its component traits in a QTL atlas, as a valuable resource for the maize community. To this end, 1,177 QTL related to maize yield were collected from 56 studies published between 1992 and 2018. These QTL were projected to genetic map “IBM2 2008 Neighbors”, which led to the identification of 135 meta-QTL. Some genomic regions appear to be hotspots for yield-related meta-QTL, often affecting more than one of the investigated traits. Moreover, we catalogued 20 major maize loci associated with yield and identified 65 maize homologs of 21 rice yield-related genes. Interestingly, we found that a significant proportion of them are located in meta-QTL regions. Collectively, this study provides a reference for QTL fine-mapping and gene cloning, as well as for molecular marker-assisted breeding of yield-related traits in maize. 相似文献
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Candolfi M. Bigler F. Campbell P. Heimbach U. Schmuck R. Angeli G. Bakker F. Brown K. Carli G. Dinter A. Forti D. Forster R. Gathmann A. Hassan S. Mead-Briggs M. Melandri M. Neumann P. Pasqualini E. Powell W. Reboulet J. -N. Romijn K. Sechser B. Thieme Th. Ufer A. Vergnet Ch. Vogt H. 《Anzeiger für Sch?dlingskunde》2000,73(6):141-147
This paper is a guidance document for side-effect testing with plant protection products on non-target arthropods under semi-field
and field conditions. The principles, methods, endpoints and interpretation of non-target arthropod semi-field and field trials
which should be conducted for registration of plant protection products in the European Union are presented and discussed.
The recommendations presented reflect the opinions of the experts from authority, academia, industry and consulting which
participated at the IOBC (International Organisation of Biological Control), BART (Beneficial Arthropod Regulatory Testing)
group and EPPO (European Plant Protection Organisation) Joint Initiative workshop held in Versailles (France) on the 25–26
October, 1999. 相似文献
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