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Surveillance for Newcastle disease outbreak stays pertinent 总被引:2,自引:0,他引:2
Haneveld JK 《Tijdschrift voor diergeneeskunde》2011,136(4):262-263
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Rojas R. Glenda Patiño Fabián Pérez Jesús Medina Claudio Lares María Méndez César Aular Johan Parkhouse R. M. E. Cortéz María M. 《Tropical animal health and production》2019,51(1):165-169
Tropical Animal Health and Production - The aim of this study was to assess transmission of Taenia solium cysticercosis in Palmarito Arriba, a small village in the rural area of the Portuguesa... 相似文献
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Johan H. Smelt Ariette E. Van De Peppel-Groen Minze Leistra 《Pest management science》1995,44(4):323-334
The transformation of aldicarb sulfoxide and aldicarb sulfone was studied in incubations with water-saturated subsoils under simulated field conditions at 10°C. The subsoils were collected at four locations from beneath the water table at a depth of 2.5 to 3.5 m. In three of the subsoils, the half-life of sulfoxide, incubated at concentrations of 0.14-0.17 mg litre?1, ranged from 0.7 to 2.8 years. At higher concentrations (8-13 mg litre?1), its half-life ranged from 3.4 to 6.4 years. At the lower concentration, a large fraction of sulfoxide was transformed into sulfone. The rates of transformation of the sulfone at the lower concentration in the three subsoils corresponded to half-lives of 3.3 to 8.1 years, but in only one subsoil was a significant transformation rate (half-life 6.7 years) measured at the higher concentration during the 2.3-year incubation period. The half-lives at the lower concentrations were more like those in field studies, and perhaps would still underestimate transformation rates under field conditions. After a year, 2.5-15% of the higher sulfoxide and sulfone doses had been trapped as [14C] carbon dioxide. In the fourth subsoil, with more anaerobic conditions, the half-life of sulfoxide at both concentrations was less than 0.02 year and that of sulfone was about 0.04 year. Four or five radio-labelled transformation products could be traced in this subsoil and about half of the dose of both compounds was trapped as [14C] carbon dioxide. 相似文献
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A procedure for the isolation of microsomes containing cytochrome-P450 isozymes from Ustilago maydis is described. Yields of P450 amount to approximately 19(±+ 6) pmol mg?1 of microsomal protein. The wavelength of maximum absorbance of the reduced carbon monoxide difference spectrum is 448-449 nm. The azole fungicides prochloraz, etaconazole, imazalil, triadimefon and 3-(2,4-dichlorophenyl)-2-(1H-1,2,4-triazol-1-yl)-4(3H)-quinazoline, which differ markedly in toxicity to U. maydis, all induce type II binding difference spectra at extremely low concentrations (10?9-10?8 M). The DMI concentrations which cause half saturation of type II binding difference spectra (IC50) do not correlate with the fungicidal activities of the azoles. Binding of carbon monoxide to ferrous cytochrome-P450 was only slightly inhibited to different degrees by the DMIs tested. However, the inhibition of carbon monoxide binding also does not correlate with fungitoxicity of the DMIs. The results in this paper suggest that the spectrophotometric studies with this preparation are not useful for evaluating selective toxicity of DMIs to intact sporidia of U. maydis. 相似文献
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Johan C. Kapteyn Richard J. Milling Donald J. Simpson Maarten A. De Waard 《Pest management science》1994,40(4):313-319
The sensitivity of cytochrome-P450-dependent sterol 14α-demethylase (P45014DM) to prochloraz and several prochloraz analogues was studied in a cell-free assay of Botrytis cinerea Pers. ex Fr. The EC50 values (concentrations which inhibited radial growth of B. cinerea by 50%) of the compounds tested ranged from 3.3 × 10 ?8 to 1.7 × 10 ?5 M. The IV50 values (concentrations which inhibited cell-free C4-demethyl sterol synthesis by 50%) in cell-free assays of B. cinerea ranged from 2.6 × 10 ?9 to 4.4 × 10 ?7 M. Ranking compounds in terms of their relative inhibitory potencies showed quite similar trends to the order of fungitoxicity, but the IC50 values did not quantitatively reflect the differences in toxicity. Therefore, the differential inhibition of cell-free P45014DM activity by these compounds cannot fully account for their differences in activity towards B. cinerea. Additional mechanisms must be involved. The compounds tested were generally more potent in the B. cinerea assay than in similar assays developed for Penicillium italicum Wehmer and, in particular, Saccharomyces cerevisiae Meyen. This correlated with the relatively higher activity of most test compounds to B. cinerea. Results suggest that the cell-free assay of B. cinerea is more useful to evaluate candidate fungicides as inhibitors of sterol 14α-demethyiase activity than similar assays from model organisms. The present study confirms that the affinity of prochloraz analogues for P45014DM depends on the nature of the N-1 substituent of the imidazole and the azole ring. It was also found that addition of an amino group at C-2 of the imidazole moiety of prochloraz gave a compound (6) which inhibited 4, 4-demethyl sterol biosynthesis in B. cinerea at a different site from the P45014DM. This was confirmed by the observation that laboratory-generated triadimenol-resistant isolates of B. cinerea showed reduced sensitivity to triadimenol and prochloraz, but not to compound 6. 相似文献
490.
Haneveld JK 《Tijdschrift voor diergeneeskunde》2008,133(14-15):622-623