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E. A. Hagen‐Plantinga G. Bosch W. H. Hendriks 《Journal of animal physiology and animal nutrition》2014,98(3):491-496
The aim of this study was to determine possible differences in felinine excretion between domesticated cat breeds. For this purpose, urine was collected from a total of 83 privately owned entire male cats from eight different breeds in the Netherlands during the period of November 2010 till November 2011. In the collected samples, free felinine and creatinine concentrations were measured. Free felinine concentrations were expressed relative to the urinary creatinine concentration to compensate for possible variations in renal output. The mean (±SD) felinine:creatinine (Fel:Cr) ratio as measured over all cats was 0.702 (±0.265). Both the Abyssinian and Sphynx breeds showed the highest Fel:Cr ratio (0.878 ± 0.162 and 0.878 ± 0.341 respectively) which significantly differed from the ratios of the British Shorthairs (0.584 ± 0.220), Birmans (0.614 ± 0.266), Norwegian Forest cats (0.566 ± 0.296) and Siberian cats (0.627 ± 0.124). The Fel:Cr ratios of the Persians (0.792 ± 0.284) and Ragdolls (0.673 ± 0.256) showed no statistical difference with either of the other breeds. A significant proportion of the observed variation between the different feline breeds could be explained by hair growth, as both hair growth and felinine production compete for available cysteine. Shorthaired and hairless cat breeds generally showed a higher Fel:Cr ratio compared to longhaired cat breeds, with the exception of Persian cats. Further research is warranted to more closely study the effect of hair growth on felinine production. 相似文献
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J. R. Caradus A. C. MacKay D. R. Woodfield J. van den Bosch S. Wewala 《Euphytica》1989,42(1-2):183-196
Summary Morphology, flowering, cyanogenesis and leaf markings of 109 white clover (Trifolium repens L.) cultivars, grown as spaced plants and in small plots, were measured. Principal component analysis and cluster analysis were used to compare cultivars. Cultivars were classified into four broad groups. The most important criteria for distinguishing between groups were leaf size, cyanogenesis and combinations of these. Group I, termed small, included small-leaved, prostrate cultivars; Group II, termed intermediate, included the majority of the cultivars which were characterised by medium sized leaves and relatively low cyanogenesis levels; Group III, termed large, included the large-leaved highly cyanogenic cultivars; and Group IV, termed ladino, included large-leaved acyanogenic cultivars. 相似文献
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M. S. Reed I. Fazey L. C. Stringer C. M. Raymond M. Akhtar‐Schuster G. Begni H. Bigas S. Brehm J. Briggs R. Bryce S. Buckmaster R. Chanda J. Davies E. Diez W. Essahli A. Evely N. Geeson I. Hartmann J. Holden K. Hubacek A. A. R. Ioris B. Kruger P. Laureano J. Phillipson C. Prell C. H. Quinn A. D. Reeves M. Seely R. Thomas M. J. van der Werff Ten Bosch P. Vergunst L. Wagner 《Land Degradation \u0026amp; Development》2013,24(4):307-322
It is increasingly recognised that land degradation monitoring and assessment can benefit from incorporating multiple sources of knowledge, using a variety of methods at different scales, including the perspectives of researchers, land managers and other stakeholders. However, the knowledge and methods required to achieve this are often dispersed across individuals and organisations at different levels and locations. Appropriate knowledge management mechanisms are therefore required to more efficiently harness these different sources of knowledge and facilitate their broader dissemination and application. This paper examines what knowledge is, how it is generated and explores how it may be stored, transferred and exchanged between knowledge producers and users before it is applied to monitor and assess land degradation at the local scale. It suggests that knowledge management can also benefit from the development of mechanisms that promote changes in understanding and efficient means of accessing and/or brokering knowledge. Broadly, these processes for knowledge management can (i) help identify and share good practices and build capacity for land degradation monitoring at different scales and in different contexts and (ii) create knowledge networks to share lessons learned and monitoring data among and between different stakeholders, scales and locations. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献