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691.
Growth promotion of maize by legume soils 总被引:4,自引:0,他引:4
Maize (Zea mays cv W64A × W182E) was grown in a low nutrient sandy loam. Inoculation with legume soils (4.1% v/v) gave a 3 to 4 fold increase
in shoot growth relative to the control after 5 to 8 weeks growth in greenhouse conditions. Plants were routinely irrigated
with 1/10 Hoagland solution (with 10mM KNO3). With half strength Hoagland solution (10mM KNO3) there was no clear growth response. This growth response was observed with a variety of legume soils but not with any of
the maize soils tested. The response to alfalfa soil was eliminated or much reduced by gamma irradiation (3.6 Mrad) or autoclaving
of the inoculum. The bactericide streptomycin had no effect on the growth response whereas the fungicides benomyl and PCNB
eliminated it. This suggests that fungi and not bacteria are involved in the growth promotion. 相似文献
692.
693.
694.
A detailed method is presented tor the creation of head-to-tail multimers of short blunt restriction fragments, ligaled into
a plasmid vector in a singletube: reaction. Random priming of the concatemer insert readily yields hybridization probes of
high specificity, unattainable from the short monomer fragments. 相似文献
695.
A. C. Agnello E. D. van Hullebusch G. Esposito 《International journal of phytoremediation》2015,17(7):669-677
Enhanced phytoremediation adding biodegradable amendments like low molecular weight organic acids and surfactants is an interesting area of current research to overcome the limitation that represents low bioavailability of pollutants in soils. However, prior to their use in assisted phytoremediation, it is necessary to test if amendments per se exert any toxic effect to plants and to optimize their application mode. In this context, the present study assessed the effects of citric acid and Tween® 80 (polyethylene glycol sorbitan monooleate) on the development of alfalfa (Medicago sativa) plants, as influenced by their concentration and frequency of application, in order to evaluate the feasibility for their future use in enhanced phytoremediation of multi-contaminated soils. The results showed that citric acid negatively affected plant germination, while it did not have any significant effect on biomass or chlorophyll content. In turn, Tween® 80 did not affect plant germination and showed a trend to increase biomass, as well as it did not have any significant effect on chlorophyll levels. M. sativa appeared to tolerate citric acid and Tween® 80 at the tested concentrations, applied weekly. Consequently, citric acid and Tween® 80 could potentially be utilized to assist phytoremediation of contaminated soils vegetated with M. sativa. 相似文献
696.
697.
Jan Roosien Alberto N. Sarachu Fieke Alblas Lous Van Vloten-Doting 《Plant molecular biology》1983,2(2):85-88
A mutant of alfalfa mosaic virus (AMV), which in contrast to wild type (wt) can invade cowpea plants systemically, is replicated more efficiently in cowpea protoplasts than the wt. Mutant preparations isolated from infected cowpea protoplasts contained a higher amount of middle component (M, containing RNA 2) than wt preparations. Both in cowpea plants and in cowpea protoplasts a wt phenotype is obtained upon addition of wt M to this mutant, suggesting a correlation between the type of plant reaction evoked by the virus infection and the regulation of viral RNA synthesis. 相似文献
698.
Martha C. Hawes Laura Y. Smith Martha Stephenson 《Plant Cell, Tissue and Organ Culture》1991,27(3):303-308
Root border cells were isolated from alfalfa seedlings, and incubated in culture medium with growth regulators. Alfalfa seedlings yielded 1500±100 cells per root, and initial viability of the cells was 95±5%. Multiple cell divisions occurred in the border cells within two weeks. Cell clusters transferred to solidified medium containing growth regulators developed into rapidly growing, friable callus. When transferred to growth regulator-free medium, some of the calluses generated normal roots.Abbreviations BRD cells
border cells
- SHDN
Schenk & Hildebrandt salts medium with growth regulators
- SHO
Schenk & Hildebrandt salts medium without growth regulators
- NAA
I-naphthaleneacetic acid 相似文献
699.
Plamen D. Denchev Alexander I. Kuklin Atanas I. Atanassov Alan H. Scragg 《Plant Cell, Tissue and Organ Culture》1993,33(1):67-73
A method for direct somatic embryogenesis in alfalfa (Medicago falcata) is described. The time course in the development phase has been followed for fresh weight, cell density, pH, sugar uptake and embryo number and type. The method of disrupting the explant material has also been shown to influence subsequent embryo formation. 相似文献
700.
The pathogenicity of two populations of the northern root-knot nematode, Meloidogyne hapla Chitwood, population 1 (P1) from alfalfa and population 2 (P2) from sainfoin, was studied on both alfalfa and sainfoin for 25 weeks. Alfalfa and sainfoin plants inoculated with P2 had significantly (P ≤ 0.05) higher mortality than plants inoculated with P1. Plant stands over all weeks for the uninoculated control, P1, and P2 were 90.5, 78.5, and 64.0% for alfalfa and 84.5, 51.0, and 41.0% for sainfoin, respectively. The increased virulence of P2 was again shown when means of plant species were combined (inoculation × week of count interaction). Plants inoculated with P2 had significantly higher mortality than either those inoculated with P1 or the uninoculated control beginning at week 7 and continuing through week 25. Plant stands over species at 25 weeks for the uninoculated control, P1, and P2 were 82.5, 29.0, and 18.0%, respectively. Sainfoin was significantly more susceptible to either population than alfalfa (plant species × week of count interaction). Separation between species first occurred after week 7 and continued until week 25. Percentages of plants remaining for alfalfa and sainfoin were 61.5 and 25.0 after 25 weeks. Significantly higher reproduction occurred in the alfalfa plants remaining after 25 weeks in P2 than in P1. Mean number of eggs per root system were 60,371 for P1 and 104,438 for P2, a difference of 42%. The results of this study indicate a need for breeders to adequately sample nematode populations present in the intended area of cultivar use and to design screening procedures to account for population pathogenicity variability. 相似文献