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961.
Nuria Bonilla Carmen Vida Maira Martínez-Alonso Blanca B. Landa Nuria Gaju Francisco M. Cazorla Antonio de Vicente 《Applied and environmental microbiology》2015,81(10):3405-3418
One of the main avocado diseases in southern Spain is white root rot caused by the fungus Rosellinia necatrix Prill. The use of organic soil amendments to enhance the suppressiveness of natural soil is an inviting approach that has successfully controlled other soilborne pathogens. This study tested the suppressive capacity of different organic amendments against R. necatrix and analyzed their effects on soil microbial communities and enzymatic activities. Two-year-old avocado trees were grown in soil treated with composted organic amendments and then used for inoculation assays. All of the organic treatments reduced disease development in comparison to unamended control soil, especially yard waste (YW) and almond shells (AS). The YW had a strong effect on microbial communities in bulk soil and produced larger population levels and diversity, higher hydrolytic activity and strong changes in the bacterial community composition of bulk soil, suggesting a mechanism of general suppression. Amendment with AS induced more subtle changes in bacterial community composition and specific enzymatic activities, with the strongest effects observed in the rhizosphere. Even if the effect was not strong, the changes caused by AS in bulk soil microbiota were related to the direct inhibition of R. necatrix by this amendment, most likely being connected to specific populations able to recolonize conducive soil after pasteurization. All of the organic amendments assayed in this study were able to suppress white root rot, although their suppressiveness appears to be mediated differentially. 相似文献
962.
Angela P. Sánchez Carolina Pardo‐Diaz Juan Enciso‐Romero Astrid Muñoz Chris D. Jiggins Mauricio Linares 《Evolution; international journal of organic evolution》2015,69(6):1619-1629
Heliconius butterflies provide good examples of both homoploid hybrid speciation and ecological speciation. In particular, examples of adaptive introgression have been detected among the subspecies of Heliconius timareta, which acquired red color pattern elements from H. melpomene. We tested whether the introgression of red wing pattern elements into H. timareta florencia might also be associated with incipient reproductive isolation (RI) from its close relative, H. timareta subsp. nov., found in the eastern Andes. No choice experiments show a 50% reduction in mating between females of H. t. subsp. nov. and males of H .t. florencia, but not in the reciprocal direction. In choice experiments using wing models, males of H. timareta subsp. nov. approach and court red phenotypes less than their own, whereas males of H. t. florencia prefer models with a red phenotype. Intrinsic postzygotic isolation was not detected in crosses between these H. timareta races. These results suggest that a color pattern trait gained by introgression is triggering RI between H. timareta subsp. nov. and H. t. florencia. 相似文献
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965.
Positive-strand RNA viruses genome replication invariably is associated with vesicles or other rearranged cellular membranes. Brome mosaic virus (BMV) RNA replication occurs on perinuclear endoplasmic reticulum (ER) membranes in ~70 nm vesicular invaginations (spherules). BMV RNA replication vesicles show multiple parallels with membrane-enveloped, budding retrovirus virions, whose envelopment and release depend on the host ESCRT (endosomal sorting complexes required for transport) membrane-remodeling machinery. We now find that deleting components of the ESCRT pathway results in at least two distinct BMV phenotypes. One group of genes regulate RNA replication and the frequency of viral replication complex formation, but had no effect on spherule size, while a second group of genes regulate RNA replication in a way or ways independent of spherule formation. In particular, deleting SNF7 inhibits BMV RNA replication > 25-fold and abolishes detectable BMV spherule formation, even though the BMV RNA replication proteins accumulate and localize normally on perinuclear ER membranes. Moreover, BMV ESCRT recruitment and spherule assembly depend on different sets of protein-protein interactions from those used by multivesicular body vesicles, HIV-1 virion budding, or tomato bushy stunt virus (TBSV) spherule formation. These and other data demonstrate that BMV requires cellular ESCRT components for proper formation and function of its vesicular RNA replication compartments. The results highlight growing but diverse interactions of ESCRT factors with many viruses and viral processes, and potential value of the ESCRT pathway as a target for broad-spectrum antiviral resistance. 相似文献
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968.
Judd AS Souers AJ Wodka D Zhao G Mulhern MM Iyengar RR Gao J Lynch JK Freeman JC Falls HD Brodjian S Dayton BD Reilly RM Gintant G Limberis JT Mikhail A Leitza ST Houseman KA Diaz G Bush EN Shapiro R Knourek-Segel V Hernandez LE Marsh KC Sham HL Collins CA Kym PR 《Bioorganic & medicinal chemistry letters》2007,17(8):2365-2371
A series of potent 2-carboxychromone-based melanin-concentrating hormone receptor 1 (MCHr1) antagonists were synthesized and evaluated for hERG (human Ether-a-go-go Related Gene) channel affinity and functional blockade. Basic dialkylamine-terminated analogs were found to weakly bind the hERG channel and provided marked improvement in a functional patch-clamp assay versus previously reported antagonists of the series. 相似文献
969.
Souers AJ Iyengar RR Judd AS Beno DW Gao J Zhao G Brune ME Napier JJ Mulhern MM Lynch JK Freeman JC Wodka D Chen CJ Falls HD Brodjian S Dayton BD Diaz GJ Bush EN Shapiro R Droz BA Knourek-Segel V Hernandez LE Marsh KC Reilly RM Sham HL Collins CA Kym PR 《Bioorganic & medicinal chemistry letters》2007,17(4):884-889
The incorporation of constrained tertiary amines into an existing class of N-benzyl-4-aminopiperidinyl chromone-based MCHr1 antagonists led to the identification of a series of chiral racemic compounds that displayed good to excellent functional potency, binding affinity, and selectivity over the hERG channel. Further separation of two distinct chiral racemic compounds into their corresponding pairs of enantiomers revealed a considerable selectivity for MCHr1 for one configuration, in addition to a striking difference in oral exposure between one pair of enantiomers in diet-induced obese mice. Oral administration of the most potent compound in this class in the same animal model led to significant reduction of fat mass in a semi-chronic model for weight loss. 相似文献
970.
Effects of potato plants expressing a barley cystatin on the predatory bug Podisus maculiventris via herbivorous prey feeding on the plant 总被引:1,自引:0,他引:1
Alvarez-Alfageme F Martínez M Pascual-Ruiz S Castañera P Diaz I Ortego F 《Transgenic research》2007,16(1):1-13
The aim of this study was to assess the effects of potato plants expressing a barley cystatin on a potentially cystatin-susceptible
natural enemy by predation on susceptible and non-susceptible preys feeding on the plant. We have focussed on the impact of
the variant HvCPI-1 C68 → G, in which the only cysteine residue was changed by a glycine, on the growth and digestive physiology of the Colorado
potato beetle (CPB), Leptinotarsa decemlineata, and the Egyptian cotton leafworm (ECW), Spodoptera littoralis. Moreover, we have studied the prey-mediated effects of the barley cystatin at the third trophic level, using the predatory
spined soldier bug (SSB), Podisus maculiventris, as a model. Feeding trials conducted with CPB larvae reared on transgenic potato plants expressing the C68 → G variant resulted in significantly lower weight gains compared to those fed on non-transformed (NT) plants. On the contrary,
larger weight gains were obtained when ECW larvae, that lack digestive cysteine proteases, were reared on transgenic potato
expressing the cystatin, as compared to larvae fed on NT plants. No negative effects on survival and growth were observed
when SSB nymphs were exposed to HvCPI-1 C68 → G by predation on either CPB or ECW larvae reared on transgenic potato plants expressing the barley cystatin, despite the
fact that the inhibitor suppressed in vitro gut proteolysis of the predatory bug. To investigate the physiological background, biochemical analysis were carried out
on guts of insects dissected at the end of the feeding assays.
Fernando álvarez-Alfageme and Manuel Martínez are contributed equally to this work. 相似文献