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Yield of micropropagated sugarcane varieties in different soil types following inoculation with diazotrophic bacteria 总被引:4,自引:1,他引:3
André Luiz Martinez de Oliveira Erineudo Lima de Canuto Segundo Urquiaga Veronica Massena Reis José Ivo Baldani 《Plant and Soil》2006,284(1-2):23-32
It is well described that the beneficial interactions between plants and bacteria are genotype and site specific. Brazilian
sugarcane varieties can obtain up to 70% of their nitrogen requirement from biological nitrogen fixation (BNF), and this contribution
is related to the Brazilian breeding and selection processes, by example of the variety SP70-1143. In this study the effect
of two inoculation mixtures containing diazotrophic bacteria in our earlier pot experiment was evaluated with two sugarcane
varieties, a known responder, SP70-1143, and a newly selected variety, SP81-3250, to investigate the sugarcane genotype effect
and the role of the mixtures. The sugarcane varieties SP70-1143 and SP81-3250 were grown under commercial field conditions
at three sites with contrasting soil types: an Alfisol, an Oxisol and an Ultisol that means a low, medium and high natural
fertility respectively. The stem yield and BNF contribution in response to bacterial inoculation were influenced by the strain
combinations in the inoculum, the plant genotype, and the soil type and nitrogen fertilization, confirming the genetic and
environmental influence in PGP-bacteria interactions. Inoculation effects on the BNF contribution and stem yield increased
in the variety SP70-1143 grown in the Alfisol without nitrogen fertilization for three consecutive crops, and it was equivalent
to the annual nitrogen fertilization. The plants grown in the Oxisol showed small increases in the productivity of the variety
SP70-1143, and in the Ultisol the sugarcane plants presented even decreases in the stem productivity due to inoculation with
diazotrophic bacteria mixtures. The results demonstrate the feasibility of the inoculation technology using diazotrophic bacteria
in micropropagated sugarcane varieties grown in soils with low to medium levels of fertility. In addition, the results also
indicated that specific plant – bacteria – environment combinations are needed to harness the full benefits of BNF.
Section Editor: C. P. Vance 相似文献
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AbstractThe location of nectar secretion in flowers of Jaltomata has not been identified with certainty until now: removal of the corolla and androecium from one side of living flowers allowed us to see, in progress, nectar secretion by the ovarian nectary. We studied Jaltomata quipuscoae, a wild plant that grows in southern Peru and produces copious, red floral nectar. Unmanipulated flowers do not set fruit in a pollinator-free greenhouse, demonstrating lack of autogamy, but self-compatibility was demonstrated by manual self-pollinations leading to fruit-set. Anther dehiscence is staggered with the anthers of a flower dehiscing over hours on the same day. The corolla and nectar are UV-absorptive. Flowers last 4–10 days, are usually protogynous during the first day the corolla is open, and do not close for the night. 相似文献
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Slowly adapting stretch receptor (SAO) pacemaker neurons, driven with periodic tugs, were analyzed by way of Poincaré mappings (Appendix). Two behaviors were apparent, i) Intermittency characterized previously unclear situations: discharges shifted irregularly between prolonged epochs where spike phases (relative to tugs) and intervals barely changed (slid), and brief bursts with marked variations (skipped), ii) Locking was well-known: phases and intervals remained almost fixed, regardless of the initiation. Changing frequencies, map domains with locking (ordered according to spikes/tugs ratios), alternated with intermittent ones. The best fit for any experimental map was a curve, not straight but certainly unidimensional, continuous and monotonic; it varied characteristically with frequency. This suggested relations called diffeomorphisms, implying periodicity and quasi-periodicity. Outcomes, expanding previous knowledge and meaningful biologically, were i)a precise, exhaustive behavior list (including between behavior transitions) and ii)a thorough understanding or model. This, in turn, provides norms for more specific models (single-variable ones suffice), constraints upon basic mechanisms (one variable, reflecting several real ones combined, should behave as the phase), and forecasts for future experimentation (e.g., unexamined tug frequencies and amplitudes).Supported by funds from CONACYT (PCEXCNA 040539) to ODM and a donation from Trent J. Wells Inc. to JPS 相似文献
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Soares Isis Capella Pacheco Rafael Sanches da Silva Cleudison Gabriel Nascimento Santos Rafael Salazar Baldani Jose Ivo Urquiaga Segundo Vidal Marcia Soares Simoes-Araujo Jean Luiz 《Plant and Soil》2021,462(1-2):525-541
Plant and Soil - Soil microbiome roles in agriculture is becoming more and more important. This importance is also reflected on the way plants are seen: complex organisms formed by the plant itself... 相似文献
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Huergo-Zapico L Gonzalez-Rodriguez AP Contesti J Gonzalez E López-Soto A Fernandez-Guizan A Acebes-Huerta A de Los Toyos JR Lopez-Larrea C Groh V Spies T Gonzalez S 《Cancer immunology, immunotherapy : CII》2012,61(8):1201-1210
MICA is a ligand of the activating receptor NKG2D, expressed by NK and T cells. MICA expression is induced in cancer cells favoring their elimination by the immune system; however, many advanced tumors shed soluble MICA (sMICA), which impairs NKG2D-mediated cytotoxicity. ERp5 and GRP78 are endoplasmic reticulum-resident proteins that are translocated to the surface of epithelial tumor cells where they interact with MICA and are involved in sMICA shedding. In this study, we analyze the role of ERp5 and GRP78 in sMICA shedding in chronic lymphocytic leukemia (CLL). Immunofluorescence and flow cytometry analyses showed that ERp5 and GRP78 were significantly expressed on the surface of B cells and leukemia cells, but they were not expressed on T cells. The expression of ERp5 and GRP78 was significantly higher in leukemia cells than in B cells from controls. ERp5 and GRP78 co-localized with MICA on the surface of leukemia cells and the levels of expression of ERp5 and GRP78 correlated with the level of expression of membrane-bound MICA in CLL patients. Associated with higher expression of membrane-bound ERp5 and GRP78, serum sMICA levels were approximately threefold higher in patients than in controls. Elevated sMICA levels in CLL patients were associated with the down-modulation of NKG2D surface expression on CD8 T cells. Finally, pharmacological inhibition of B cell lines and stimulated leukemia cells showed that ERp5 activity is involved in sMICA shedding in CLL. In conclusion, these results uncover a molecular mechanism which regulates MICA protein shedding and immune evasion in CLL. 相似文献
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Segundo Urquiaga Rogério P. Xavier Rafael F. de Morais Rafael B. Batista Nivaldo Schultz José M. Leite Jerusa Maia e Sá Karolina P. Barbosa Alexander S. de Resende Bruno J. R. Alves Robert M. Boddey 《Plant and Soil》2012,356(1-2):5-21