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191.
Aline De Vleminck Koen Pardon Kim Beernaert Dirk Houttekier Robert Vander Stichele Luc Deliens 《PloS one》2016,11(4)
ObjectivesTo explore how GPs conceptualise advance care planning (ACP), based on their experiences with ACP in their practice.MethodsFive focus groups were held with 36 GPs. Discussions were analysed using a constant comparative method.ResultsFour overarching themes in the conceptualisations of ACP were discerned: (1) the organisation of professional care required to meet patients’ needs, (2) the process of preparing for death and discussing palliative care options, (3) the discussion of care goals and treatment decisions, (4) the completion of advance directives. Within these themes, ACP was both conceptualised in terms of content of ACP and/or in terms of tasks for the GP. A specific task that was mentioned throughout the discussion of the four different themes was (5) the task of actively initiating ACP by the GP versus passively waiting for patients’ initiation.ConclusionsThis study illustrates that GPs have varying conceptualisations of ACP, of which some are more limited to specific aspects of ACP. A shared conceptualisation and agreement on the purpose and goals of ACP is needed to ensure successful implementation, as well as a systematic integration of ACP in routine practice that could lead to a better uptake of all the important elements of ACP. 相似文献
192.
Thiago Aparecido da Silva Vania Sammartino Mariano Aline Sardinha-Silva Maria Aparecida de Souza Tiago Wilson Patriarca Mineo Maria Cristina Roque-Barreira 《PloS one》2016,11(2)
ArtinM is a D-mannose-binding lectin extracted from the seeds of Artocarpus heterophyllus that interacts with TLR2 N-glycans and activates antigen-presenting cells (APCs), as manifested by IL-12 production. In vivo ArtinM administration induces Th1 immunity and confers protection against infection with several intracellular pathogens. In the murine model of Candida albicans infection, it was verified that, in addition to Th1, ArtinM induces Th17 immunity manifested by high IL-17 levels in the treated animals. Herein, we investigated the mechanisms accounting for the ArtinM-induced IL-17 production. We found that ArtinM stimulates the IL-17 production by spleen cells in BALB/c or C57BL/6 mice, a response that was significantly reduced in the absence of IL-23, MyD88, or IL-1R. Furthermore, we showed that ArtinM directly induced the IL-23 mRNA expression and the IL-1 production by macrophages. Consistently, in cell suspensions depleted of macrophages, the IL-17 production stimulated by ArtinM was reduced by 53% and the exogenous IL-23 acted synergistically with ArtinM in promoting IL-17 production by spleen cell suspensions. We verified that the absence of IL-23, IL-1R, or MyD88 inhibited, but did not block, the IL-17 production by ArtinM-stimulated spleen cells. Therefore, we investigated whether ArtinM exerts a direct effect on CD4+ T cells in promoting IL-17 production. Indeed, spleen cell suspensions depleted of CD4+ T cells responded to ArtinM with very low levels of IL-17 release. Likewise, isolated CD4+ T cells under ArtinM stimulus augmented the expression of TGF-β mRNA and released high levels of IL-17. Considering the observed synergism between IL-23 and ArtinM, we used cells from IL-23 KO mice to assess the direct effect of lectin on CD4+ T cells. We verified that ArtinM increased the IL-17 production significantly, a response that was inhibited when the CD4+ T cells were pre-incubated with anti-CD3 antibody. In conclusion, ArtinM stimulates the production of IL-17 by CD4+ T cells in two major ways: (I) through the induction of IL-23 and IL-1 by APCs and (II) through the direct interaction with CD3 on the CD4+ T cells. This study contributes to elucidation of mechanisms accounting for the property of ArtinM in inducing Th17 immunity and opens new perspectives in designing strategies for modulating immunity by using carbohydrate recognition agents. 相似文献
193.
Grazielle R. Goes Peter S. Rocha Aline R. S. Diniz Pedro H. N. Aguiar Carlos R. Machado Leda Q. Vieira 《PLoS neglected tropical diseases》2016,10(4)
Background
During Trypanosoma cruzi infection, macrophages produce reactive oxygen species (ROS) in a process called respiratory burst. Several works have aimed to elucidate the role of ROS during T. cruzi infection and the results obtained are sometimes contradictory. T. cruzi has a highly efficiently regulated antioxidant machinery to deal with the oxidative burst, but the parasite macromolecules, particularly DNA, may still suffer oxidative damage. Guanine (G) is the most vulnerable base and its oxidation results in formation of 8-oxoG, a cellular marker of oxidative stress.Methodology/Principal Findings
In order to investigate the contribution of ROS in T. cruzi survival and infection, we utilized mice deficient in the gp91phox (Phox KO) subunit of NADPH oxidase and parasites that overexpress the enzyme EcMutT (from Escherichia coli) or TcMTH (from T. cruzi), which is responsible for removing 8-oxo-dGTP from the nucleotide pool. The modified parasites presented enhanced replication inside murine inflammatory macrophages from C57BL/6 WT mice when compared with control parasites. Interestingly, when Phox KO macrophages were infected with these parasites, we observed a decreased number of all parasites when compared with macrophages from C57BL/6 WT. Scavengers for ROS also decreased parasite growth in WT macrophages. In addition, treatment of macrophages or parasites with hydrogen peroxide increased parasite replication in Phox KO mice and in vivo.Conclusions
Our results indicate a paradoxical role for ROS since modified parasites multiply better inside macrophages, but proliferation is significantly reduced when ROS is removed from the host cell. Our findings suggest that ROS can work like a signaling molecule, contributing to T. cruzi growth inside the cells. 相似文献194.
195.
How predation by Podisus nigrispinus is influenced by developmental stage and density of its prey Alabama argillacea 总被引:1,自引:0,他引:1
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Bárbara Davis B. dos Santos Francisco S. Ramalho José B. Malaquias Aline C. S. Lira Jéssica K. S. Pachú Francisco S. Fernandes José C. Zanuncio 《Entomologia Experimentalis et Applicata》2016,158(2):142-151
The functional response of a predator to the density of its prey is affected by several factors, including the prey's developmental stage. This study evaluated the functional response of Podisus nigrispinus (Dallas) (Hemiptera: Heteroptera: Pentatomidae) females to fourth instars and pupae of Alabama argillacea (Hübner) (Lepidoptera: Noctuidae), an important pest of cotton (Gossypium hirsutum L., Malvaceae) in Brazil. The prey were exposed to the predator for 12 and 24 h, and in densities of 1, 6, 12, 18, 24, and 30 items per predator female. The predation data were subjected to polynomial regression logistic analysis to determine the type of functional response. Holling and Rogers' equations were used to estimate parameters such as attack rate and handling time. Podisus nigrispinus females showed functional response types II and III by preying on larvae and pupae, respectively. The attack rate and handling time did not differ between the 12 and 24 h exposure times. Predation rate was higher at higher larval and pupal densities; predation was highest at a density of 30 prey items per female, and it was similar at 18 and 24 prey per predator. Understanding the interaction of predators and their food resources helps to optimize biological control strategies. It also helps the decision‐making and the improvement of release techniques of P. nigrispinus in the field. 相似文献
196.
T. F. Rakotoarisoa T. Richter H. Rakotondramanana J. Mantilla-Contreras 《Economic botany》2016,70(4):365-379
In diverse ecosystems, invasive plant species represent a serious threat for nature conservation by leading to loss of native species as well as environmental degradation. The water hyacinth (Eichhornia crassipes) belongs to the top 10 worldwide most troublesome aquatic weeds. This study assesses the use of this invasive plant as a new source of raw material for handicrafts to substitute for the traditionally used papyrus (Cyperus madagascariensis) in the poor and remote region of Lake Alaotra in Madagascar. It has been recently observed that the current exploitation of papyrus in this region adds pressure on the receding Alaotra wetland and notably decreases habitat and food resources for the locally endemic and critically endangered lemur species Hapalemur alaotrensis. Within our research, water hyacinth handicrafts were produced by local artisans and compared with papyrus handicrafts regarding production path (collection, transportation, and processing of raw material) with a focus on financial costs, workload, and selling price. In addition, structured interviews were conducted with town-based handicraft retailers and potential customers to specify market expectations (quality, design, and marketing strategies). Our study revealed that despite the requirement for a longer time regarding raw material selection and drying (7 days vs 3 days) as well as additional financial costs (23% in addition) for ornaments, water hyacinth handicrafts displayed many advantages in comparison to papyrus handicrafts: (a) assembling water hyacinth handicrafts was easier and faster (33% less time investment), (b) led to robust products that were rated as being of acceptable to very good quality by 91% of the interviewees (c) and sold at three times (mean 2.25 US$) the sale prices of the traditional papyrus handicrafts (mean 0.75 US$). The use of water hyacinth has therefore the potential to increase local household incomes, open up new markets, and attenuate the pressure on the Alaotra wetland biodiversity by reducing the use of papyrus. A SWOT (strengths, weaknesses, opportunities and threats) analysis combined with research findings on rural handicrafts was drafted to identify four main steps for promoting the market establishment of water hyacinth handicrafts at Lake Alaotra: creation of artisans’ clusters and networks, improvement of managerial and marketing competence, access to finance and exploration of markets possibilities. This research can provide insights for other small rural handicraft enterprises in developing countries facing problem with water hyacinth throughout the world. 相似文献
197.
Visitation rate of pollinators and nectar robbers to the flowers and inflorescences of Tabebuia aurea (Bignoniaceae): effects of floral display size and habitat fragmentation
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Jorge A. Lobo Davi de Lacerda Ramos Aline Cabral Braga 《Botanical journal of the Linnean Society. Linnean Society of London》2016,181(4):667-681
Large floral displays favour pollinator attraction and the import and export of pollen. However, large floral displays also have negative effects, such as increased geitonogamy, pollen discounting and nectar/pollen robber attraction. The size of the floral display can be measured at different scales (e.g. the flower, inflorescence or entire plant) and variations in one of these scales may affect the behaviour of flower visitors in different ways. Moreover, the fragmentation of natural forests may affect flower visitation rates and flower visitor behaviour. In the present study, video recordings of the inflorescences of a tree species (Tabebuia aurea) from the tropical savannah of central Brazil were used to examine the effect of floral display size at the inflorescence and tree scales on the visitation rate of pollinators and nectar robbers to the inflorescence, the number of flowers approached per visit, the number of visits per flower of potential pollinators and nectar robbers, and the interaction of these variables with the degree of landscape disturbance. Nectar production was quantified with respect to flower age. Although large bees are responsible for most of the pollination, a great diversity of flower insects visit the inflorescences of T. aurea. Other bee and hummingbird species are highly active nectar robbers. Increases in inflorescence size increase the visitation rate of pollinators to inflorescences, whereas increases in the number of inflorescences on the tree decrease visitation rates to inflorescences and flowers. This effect has been strongly correlated with urban environments in which trees with the largest floral displays are observed. Pollinating bees (and nectar robbers) visit few flowers per inflorescence and concentrate visits to a fraction of available flowers, generating an overdispersed distribution of the number of visits per inflorescence and per flower. This behaviour reflects preferential visits to young flowers (including flower buds) with a greater nectar supply. 相似文献
198.
da Silva Aline Cunha Grativol Clícia Thiebaut Flávia Hemerly Adriana Silva Ferreira Paulo Cavalcanti Gomes 《Planta》2016,243(5):1265-1277
Planta - In the present study, miRNA precursors in the genomes of three palm species were identified. Analyzes of sequence conservation and biological function of their putative targets contribute... 相似文献
199.