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131.
Raimunda Sâmia Nogueira Brilhante Pedro Henrique de Aragão Rodrigues Lucas Pereira de Alencar Giovanna Barbosa Riello Joyce Fonteles Ribeiro Jonathas Sales de Oliveira Débora de Souza Collares Maia Castelo-Branco Tereza de Jesus Pinheiro Gomes Bandeira André Jalles Monteiro Marcos Fábio Gadelha Rocha Rossana de Aguiar Cordeiro José Luciano Bezerra Moreira José Júlio Costa Sidrim 《Mycopathologia》2015,180(5-6):421-426
132.
Myrciamyia pterandrae (Diptera, Cecidomyiidae), a new galling species associated with Pterandra pyroidea (Fabaceae), an endemic plant species in Brazilian Cerrado, is described based on larva, pupa, male and female. M. pterandrae galls were collected in the municipality of Quartel de São João, State of Minas Gerais, southeastern Brazil. Larvae were removed from the galls and pupae, and adults were obtained by rearing. The specimens were mounted on slides, and the diagnostic morphological characters were illustrated. M. pterandrae is compared to Myrciamyia maricaensis Maia, 1996 the unique, previously known species of the genus. 相似文献
133.
Camille?Ferreira?Maia Breno?Ricardo?Serr?o da?Silva Allan?Klynger da?Silva?LobatoEmail authorView authors OrcID profile 《Journal of Plant Growth Regulation》2018,37(4):1099-1112
Growth and development are vital processes in the life cycles of plants. Brassinosteroids (BRs) are steroids that when exogenously applied can regulate several biological responses. The aim of this research was to investigate the possible interferences caused by the exogenous application of BR on growth and metabolism using two genotypes of the DWARF gene, MT-d and MT-D, that are BR-deficient and BR-efficient, respectively. The experiment had four treatments with two genotypes (BR-efficient and BR-deficient) and two levels of brassinosteroids (0 and 100 nM BR, described as ??BR and +?BR, respectively). This study revealed that the exogenous application of BR promoted improvement in growth, inducing increases in all variables of both genotypes evaluated. In general, BR-deficient plants sprayed with BR had effects more intense, confirming the benefits of this steroid on photosynthetic apparatus and gas exchange. The changes in the anatomical characteristics of the leaf are related to the contribution of BR on the influx and consequent fixation of CO2. In addition, modifications related to root anatomy occurred as a result of the BR action with the purpose of increasing the root protection and absorption of water and nutrients. Increases in photosynthetic pigments suggest that the role of BR is linked with chlorophyll biosynthesis and the maintenance of chloroplast integrity, resulting from associations with the increases found in the activities of antioxidant enzymes that modulate the accumulation of reactive oxygen species. 相似文献
134.
Diogo Gama Caetano Fernanda Heloise Côrtes Gonzalo Bello Sylvia Lopes Maia Teixeira Brenda Hoagland Beatriz Grinsztejn Valdilea Gonçalves Veloso Monick Lindenmeyer Guimarães Mariza Gonçalves Morgado 《Retrovirology》2018,15(1):62
Background
Despite the low level of viral replication in HIV controllers (HICs), studies have reported viral mutations related to escape from cytotoxic T-lymphocyte (CTL) response in HIV-1 plasma sequences. Thus, evaluating the dynamics of the emergence of CTL-escape mutants in HICs reservoirs is important for understanding viremia control. To analyze the HIV-1 mutational profile and dynamics of CTL-escape mutants in HICs, we selected 11 long-term non-progressor individuals and divided them into the following groups: (1) viremic controllers (VCs; n?=?5) and (2) elite controllers (ECs; n?=?6). For each individual, we used HIV-1 proviral DNA from PBMCs related to earliest (VE) and latest (VL) visits to obtain gag and nef sequences using the Illumina HiSeq system. The consensus of each mapped gene was used to assess viral divergence, and next-generation sequencing data were employed to identify SNPs and variations within and flanking CTL epitopes.Results
Divergence analysis showed higher values for nef compared to gag among the HICs. EC and VC groups showed similar divergence rates for both genes. Analysis of the number of SNPs showed that VCs present more variability in both genes. Synonymous/non-synonymous mutation ratios were?<?1 for gag among ECs and for nef among ECs and VCs, exhibiting a predominance of non-synonymous mutations. Such mutations were observed in regions encoding CTL-restricted epitopes in all individuals. All ECs presented non-synonymous mutations in CTL epitopes but generally at low frequency (<?1%); all VCs showed a high number of mutations, with significant frequency changes between VE and VL visits. A higher frequency of internal mutations was observed for gag epitopes, with significant changes across visits compared to Nef epitopes, indicating a pattern associated with differential genetic pressure.Conclusions
The high genetic conservation of HIV-1 gag and nef among ECs indicates that the higher level of viremia control restricts the evolution of both genes. Although viral replication levels in HICs are low or undetectable, all individuals exhibited CTL epitope mutations in proviral gag and nef variants, indicating that potential CTL escape mutants are present in HIC reservoirs and that situations leading to a disequilibrium of the host-virus relationship can result in the spread of CTL-escape variants.135.
Environmental change and predator diversity drive alpha and beta diversity in freshwater macro and microorganisms
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Pablo Augusto P. Antiqueira Owen L. Petchey Viviane Piccin dos Santos Valéria Maia de Oliveira Gustavo Quevedo Romero 《Global Change Biology》2018,24(8):3715-3728
Global biodiversity is eroding due to anthropogenic causes, such as climate change, habitat loss, and trophic simplification of biological communities. Most studies address only isolated causes within a single group of organisms; however, biological groups of different trophic levels may respond in particular ways to different environmental impacts. Our study used natural microcosms to investigate the predicted individual and interactive effects of warming, changes in top predator diversity, and habitat size on the alpha and beta diversity of macrofauna, microfauna, and bacteria. Alpha diversity (i.e., richness within each bromeliad) generally explained a larger proportion of the gamma diversity (partitioned in alpha and beta diversity). Overall, dissimilarity between communities occurred due to species turnover and not species loss (nestedness). Nevertheless, the three biological groups responded differently to each environmental stressor. Microfauna were the most sensitive group, with alpha and beta diversity being affected by environmental changes (warming and habitat size) and trophic structure (diversity of top predators). Macrofauna alpha and beta diversity was sensitive to changes in predator diversity and habitat size, but not warming. In contrast, the bacterial community was not influenced by the treatments. The community of each biological group was not mutually concordant with the environmental and trophic changes. Our results demonstrate that distinct anthropogenic impacts differentially affect the components of macro and microorganism diversity through direct and indirect effects (i.e., bottom‐up and top‐down effects). Therefore, a multitrophic and multispecies approach is necessary to assess the effects of different anthropogenic impacts on biodiversity. 相似文献
136.
Wei‐Qun Jiang Sílvia M. M. A. Pereira‐Lima Cristina Ventura Susana P. G. Costa Lídia Albuquerque Raquel Gonalves‐Maia Hernni L. S. Maia 《Journal of peptide science》2005,11(10):627-632
Accurate kinetic measurements of the rate constants for the acidolysis of five N-acetyl-N-(4-methoxybenzyl)-alpha,alpha-trialkyl glycine cyclohexyl amides in TFA were performed at 25 degrees C and the reactions monitored by HPLC. In all cases the results were consistent with a first order behaviour with respect to the substrate. No direct correlation was obtained with these data between the rate constant values and structure, but a good correlation coefficient was obtained when a multiple regression analysis was applied by taking advantage of a Taft equation using appropriate polar and steric substituent parameters. In a plot of the values observed for log k against those calculated by this equation all five points fell very close to the line of perfect correlation. The calculated sensitivity coefficients to polar and steric contributions were used to discuss the experimental results and showed that the acidolysis were comparatively less affected by steric effects than expected. 相似文献
137.
U. P. Jacobina S. M. Q. Lima D. Gama Maia G. Souza H. Batalha-Filho R. A. Torres 《Genetica》2018,146(6):505-515
We assessed the presence of independent evolving lineages of the trahira, Hoplias malabaricus, one of the few freshwater fish species having wide distribution in the Neotropics which is the region with the highest global diversity of freshwater fish. To achieve that goal, 58 mitochondrial sequences of cytochrome c oxidase subunit I (COI; DNA barcoding) were generated from collected samples and 85 obtained from public databases, which were analyzed in comparison to chromosomal and geological data. The magnitude of genetic diversity found among different sampling sites was greater than 2%. Molecular species delimitation methods indicated the existence of a least four distinct lineages. The recognised cytotypes did not form monophyletic groups, suggesting that the karyotypic macrostructure could be a homoplastic character. The haplotype relationships suggested secondary contacts between the ecoregions of Northern and Northeastern Brazil that were shaped by coastal routes between adjacent watersheds during the Pleistocene epoch and probable exchanges of their ichthyofaunas. Our results indicated that multiple factors have driven the diversification of H. malabaricus, from ancient geological events linked to the reactivation of tectonic faults to more recent occurrences related to eustatic changes in ocean levels. Ultimately, the magnitude of its genetic diversity suggests the necessity of revising its taxonomic status. 相似文献
138.
139.
In this study, point mutations were introduced in plant uncoupling mitochondrial protein AtUCP1, a typical member of the plant uncoupling protein (UCP) gene subfamily, in amino acid residues Lys147, Arg155 and Tyr269, located inside the so-called UCP-signatures, and in two more residues, Cys28 and His83, specific for plant UCPs. The effects of amino acid replacements on AtUCP1 biochemical properties were examined using reconstituted proteoliposomes. Residue Arg155 appears to be crucial for AtUCP1 affinity to linoleic acid (LA) whereas His83 plays an important role in AtUCP1 transport activity. Residues Cys28, Lys147, and also Tyr269 are probably essential for correct protein function, as their substitutions affected either the AtUCP1 affinity to LA and its transport activity, or sensitivity to inhibitors (purine nucleotides). Interestingly, Cys28 substitution reduced ATP inhibitory effect on AtUCP1, while Tyr269Phe mutant exhibited 2.8-fold increase in sensitivity to ATP, in accordance with the reverse mutation Phe267Tyr of mammalian UCP1. 相似文献
140.
Effect of arbuscular mycorrhizal fungi on the acclimatization of micropropagated banana plantlets 总被引:1,自引:0,他引:1
A. M. Yano-Melo L. C. Maia O.J. Saggin Jr. J. M. Lima-Filho N. F. Melo 《Mycorrhiza》1999,9(2):119-123
The effect of arbuscular mycorrhizal fungi (AMF) on micropropagated banana plantlets was evaluated during the acclimatization
period. Plants were inoculated with Acaulospora scrobiculata, Glomus clarum or Glomus etunicatum. After cultivation in a greenhouse for 3 months, height, leaf area, fresh weight and dry matter of root and shoots, level
of AMF colonization, nutrient level, photosynthesis and transpiration rate, water potential and stomatal conductance were
measured. The number of AMF spores produced in each treatment was also determined. Plantlets inoculated with AMF had greater
height, leaf area and fresh weight of shoots and roots, as well as higher rates of photosynthesis and transpiration than controls.
Plants inoculated with Glomus were superior in most of the evaluated parameters.
Accepted: 24 May 1999 相似文献