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111.
Aluminum (Al) occurs abundantly in soil and solubilized aluminum ions in acid soil inhibit plant growth, in particular, root growth. Although several toxic effects of Al on plant growth have been reported, the mechanism of Al toxicity remains to be clarified. 相似文献
112.
Achmadi Jumberi Mina Yamada Satoshi Yamada Hideyasu Fujiyama 《Soil Science and Plant Nutrition》2013,59(4):657-664
A greenhouse experiment was conducted to investigate the effect of exchangeable Na on the growth and absorption of metal elements in barley, rye, and maize. The plants were cultivated in soils whose exchangeable sodium percentages (ESP) were 6.6 (saline soil: Saline), 17.4 (saline-sodic soil: Sodic 1), and 39.6 (sodic soil: Sodic 2), which were prepared from Tottori sand dune soil (Control). The dry weight (DW) and concentrations of metal elements Ca, Mg, Mn, Zn, and Cu) in shoots were analyzed. The shoot DW was smaller with higher ESP, but in barley the difference between all the treatments was no longer observed with time. In Sodic soils, the growth of barley was vigorous, whereas rye growth was poor, and maize plants died by 5 weeks after planting. The Na concentration in shoots of all the species was higher with higher ESP. The K concentration in shoots was low at the early growth stage, but in barley it was higher in the Saline and both Sodic soils than in the Control at the subsequent stages. The concentrations of Ca and Mg in shoots of barley and maize in the Saline and both Sodic soils were higher than those in the Control, but in rye the concentrations were lowest in Sodic 2. The concentrations of Mn, Zn, and Cu in barley shoots in the Saline and bothSodic soils tended to be higher than those in the Control, whereas in rye they were lower than in the Control in both Sodic soils. Barley showed a higher ability to absorb low available microelements than rye and maize. These results indicate that barley is tolerant to sodicity as well as salinity, maize is tolerant to salinity, but is very sensitive to sodicity, and rye is moderately sensitive to both stresses. We suggest that the tolerance of grain crops to ESP involves a tolerance to a high Na concentration in shoots, the ability to keep suitable concentrations of essential cations in the presence of a high concentration of Na in shoots and the ability to absorb low available microelements. 相似文献
113.
Sobhi M. Girgis Frederic P. Bem Chrysostomos I. Dovas Athanassios Sclavounos Apostolos D. Avgelis Mina Tsagris Nikos Katis Panayota E. Kyriakopoulou 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(2):203-211
Unusual symptoms were observed on ‘Baresana’ x ‘Baresana’ Vitis vinifera hybrid vines in the Grapevine Variety Collection of the Grapevine Institute, Athens. The affected vines showed sharp angular
mosaic on leaves, along the veins and in vein angles, malformations, abortive flowers or very few berries with smaller, wrinkled
and non-germinating seeds, as well as gradual decline, severe stunting and death of the vine. Serological tests on diseased
vines for the presence of 13 known grapevine viruses gave negative results. An infectious agent was transmitted mechanically
to several herbaceous indicator plants. Koch’s Postulates were fulfilled, and the agent, proven to be a virus, was named Grapevine angular mosaic virus (GAMV). Serological tests have been developed for the virus. The most conserved polymerase region showed significant similarity
of GAMV with members of subgroup 1 of the Ilarvirus genus; however ML phylogenetic analysis could not support its clustering within this subgroup. GAMV differs serologically
and in particle morphology from Grapevine line pattern virus (GLPV) a putative member of the Ilarvirus genus that infects grapevine. It is proposed that GAMV is a novel member of the Ilarvirus genus. 相似文献
114.
Application of the amount of oxygen consumption to the investigation of the oxidation mechanism of lignin during oxygen-alkali treatment 总被引:1,自引:1,他引:0
Aiko Imai Iori Tomoda Tomoya Yokoyama Yuji Matsumoto Gyosuke Meshitsuka Guolin Tong 《Journal of Wood Science》2008,54(1):62-67
The dioxygen consumption by kraft lignin and several lignin model compounds during oxygen-alkali treatments were directly
analyzed using a dioxygen fl owmeter. The average dioxygen consumption by 200 g of kraft lignin was about 3 moles. Because
this value was as much as those obtained for monomeric phenolic lignin model compounds, guaiacol and vanillyl alcohol, it
was postulated that not only phenolic but also nonphenolic moieties in kraft lignin are extensively oxidized. The dioxygen
consumption by 0.5 moles (one equivalent of aromatic units) of a dimeric lignin model compound, guaiacylglycerol-β-guaiacyl
ether (GG), was also similar to that for 1 mole of guaiacol and vanillyl alcohol, regardless of the type of the aromatic moiety,
which supports the above postulation. The most plausible mechanism for the oxidation of nonphenolic moieties is the oxidation
of side chains of residual β-O-4 substructures by active oxygen species. By this mechanism, nonphenolic moieties in kraft lignin and GG are converted into
corresponding phenolic moieties, and the oxidation by dioxygen progresses.
Part of this article was presented at the 13th International Symposium on Wood, Fiber, and Pulping Chemistry (13th ISWFPC),
Auckland, New Zealand, May 2005 相似文献
115.
The effects of canopy and shrub layer coverage on the frequency of oviposition by a papilionid butterfly, Luehdorfia japonica, were investigated. Density of larval host plant tended to be higher where shrub layer was thinner, and the frequency of
oviposition was correlated with host plant abundance. On the other hand, host plant abundance and the frequency of oviposition
were not correlated with canopy layer coverage. Eggs were mainly found at or near the forest edge irrespective of host plant
abundance. 相似文献
116.
Hisayuki Arakawa Yohei Ohi Akira Matsumoto Kenji Takio Takumi Kimoto Katsutoshi Kawabe 《Fisheries Science》2012,78(5):1083-1090
The populations of red alga Gelidium elegans along the coast of Miyakejima Island were severely damaged by a volcanic eruption in 2000. The effect of this volcanic eruption has been long lasting, and populations of this red alga still have not recovered. We investigated the effect of seabed sediment particles derived from volcanic ash on the substrate adhesion of G.?elegans spores. The analysis provides evidence that increasing amounts of sediment particles result in lower adhesion rates of G.?elegans spores, and that smaller sediment particles have a greater influence on adhesion. The amount of seabed sediment particles around Miyakejima Island was 9.3?C1815.4?mg/cm2. This amount has changed greatly from year to year. The adhesion rate of G.?elegans spores in water around Miyakejima Island was 0?% at all points in 2008 and 2010, but it was estimated as 6.3?C38.6?% in 2009. These results suggest that there is significant inhibition of algal spore adhesion by seabed sediment particles derived from volcanic ash around Miyakejima Island. 相似文献
117.
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120.
Timothy D. Sherman Mary V. Duke Robert D. Clark Ernest F. Sanders Hiroshi Matsumoto Stephen O. Duke 《Pesticide biochemistry and physiology》1991,40(3)
Two isomeric pairs of pyrazole phenyl ether herbicides [AH 2.429, 4-chloro-1-methyl-5-(4-nitrophenoxy)-3-(trifluoromethyl)-1H-pyrazole; AH 2.430, 4-chloro-1-methyl-3-(4-nitrophenoxy)-5-(trifluoromethyl)-1H-pyrazole; AH 2.431, 5-((4-chloro-1-methyl-5-(trifluoromethyl)-1H-pyrazol-3-yl)oxy)-2-nitrobenzoic acid; and AH 2.432, 5-((4-chloro-1-methyl-3-(trifluoromethyl)-1H-pyrazol-5-yl)oxy)-2-nitrobenzoic acid were evaluated for herbicidal activity in both intact plants and in tissue sections. Their capacity to induce accumulation of porphyrins in tissue sections and to inhibit protoporphyrinogen oxidase (Protox) in vitro were determined. In whole plant tests, the order of herbicidal activity was AH 2.430 AH 2.431 > AH 2.429 > AH 2.432. AH 2.430 consistently caused light-dependent membrane leakage in both green and far-red light grown cucumber cotyledon and barley primary leaf tissue sections after incubation for 20 hr in darkness in 0.1 mM solutions. The same treatment caused marked increases in protoporphyrin IX (PPIX) content during the 20-hr dark incubation. AH 2.429 and 2.431 were less effective and not effective in all tissues in causing herbicidal damage and PPIX accumulation. AH 2.432 was ineffective in tissue section assays. Mg-PPIX levels were not significantly affected by any of the compounds. Protochlorophyllide levels were decreased by AH 2.430 and 2.431 in barley and increased by AH 2.429, 2.431, and 2.432 in cucumber. A positive relationship was found between herbicidal activity and the amount of PPIX that was caused to accumulate by each compound. All of the compounds inhibited Protox activity. Positive correlations were found between herbicidal activity in planta over a 300-fold range and in vitro Protox inhibition and the amount of PPIX caused to accumulate in vivo. These data support the view that the pyrazole phenyl ethers exert their herbicidal activity entirely through inhibition of Protox. 相似文献