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991.
Angela J. Pereira-Morales Leandro P. Casiraghi Ana Adan 《Chronobiology international》2019,36(2):225-236
Among the factors that contribute to the onset and maintenance of depressive disorders, rhythmicity of symptoms and consumption of caffeine have recently gained attention. The current study aimed to examine the differential rhythmicity of relevant variables in a sample of young participants, considering the presence of depressive symptomatology and the frequency of caffeinated drinks consumption. A significant 24-hour differential rhythmicity of mood, cognitive and physiological variables was found indicating an evening peak pattern in the participants with depressive symptoms. Interestingly, caffeinated drinks consumption was differentially associated with self-perceived peaks, according to the presence of depressive symptomatology. Our findings are among the first reports about the potential association of the 24-hours rhythmicity of relevant mood-related variables, depressive symptoms, and caffeine intake. These results support the view that the identification of risk factors for depression, and the application of novel measurements and analysis methods in the development of new preventive strategies should be a public health priority. 相似文献
992.
Mariana Morais Vidal Cristina Banks‐Leite Leandro Reverberi Tambosi rica Hasui Pedro Ferreira Develey Wesley Rodrigues Silva Paulo Roberto Guimares Jean Paul Metzger 《Ecography》2019,42(10):1765-1776
Habitat loss can trigger cascades of secondary extinctions, changing the organization of interacting assemblages. Until recently, most extinction models in interaction systems had limited ecological realism. Here, we estimate a realistic sequence of species extinctions resulting from habitat loss to assess its impacts on the structure of frugivory networks from the Brazilian Atlantic Forest. We show that realistic and random extinctions led to similar patterns. We also identified a threshold in the response of network structure to habitat loss. When forest cover was reduced to less than 40% of the landscape, network organization changed dramatically. Hence, the number of species being lost, rather than the order of species extinctions, is the key determinant of its impacts on the organization of frugivory networks. We highlight the need to conserve around 40% of forest cover to keep the basic organization of frugivory networks, a threshold already reached at the best‐preserved Brazilian Atlantic Forest bioregion. 相似文献
993.
Renato R. Hilário Leandro Jerusalinsky Sidnei Santos Raone Beltrão-Mendes Stephen F. Ferrari 《Primates; journal of primatology》2017,58(2):343-352
Identifying the factors that determine local extinction of populations is crucial to ensure species conservation. Forest-dwelling primates are especially vulnerable to habitat fragmentation, although few studies have provided systematic evidence of local extinctions. Over an 11-year period, approximately 100 remnant populations of the endangered Coimbra Filho’s titi monkey (Callicebus coimbrai) have been found within the geographic range of the species in Bahia and Sergipe, Northeast Brazil. During the present study, extinction of 13 of these populations was recorded through intensive surveys. These extinctions were detected from evidence of intensive logging and clear-cutting, interviews with local residents and systematic searches of the sites where occurrence of the species had been confirmed in previous surveys. These local extinctions represent approximately 10 % of the known populations of C. coimbrai and up to 28.3 % of the area occupied by the species. Comparison of the vegetation structure in fragments where extinction was recorded and where the species still occurs indicated that sparser understorey may be a correlate of extinction, combined with the fact that extinctions occurred within fragments characterised by relatively high levels of anthropogenic disturbance. These findings reinforce the Endangered status of the species and the urgent need for intensification of conservation measures within the most impacted areas of the geographic distribution of C. coimbrai. 相似文献
994.
995.
It is the time for oceanic seabirds: Tracking year‐round distribution of gadfly petrels across the Atlantic Ocean 下载免费PDF全文
996.
Phylogenetically closely related species tend to be more similar to each other than to more distantly related ones, a pattern called phylogenetic signal. Appropriate tests to evaluate the association between phylogenetic relatedness and trait variation among species are employed in a myriad of eco-evolutionary studies. However, most tests available to date are only suitable for datasets describing continuous traits, and are most often applicable only for single trait analysis. The Mantel test is a useful method to measure phylogenetic signal for multiple (continuous, binary and/or categorical) traits. However, the classical Mantel test does not incorporate any evolutionary model (EM) in the analysis. Here, we describe a new analytical procedure, which incorporates explicitly an evolutionary model in the standard Mantel test (EM-Mantel). We run numerical simulations to evaluate its statistical properties, under different combinations of species pool size, trait type and number. Our results showed that EM-Mantel test has appropriate type I error and acceptable power, which increases with the strength of phylogenetic signal and with species pool size but depended on trait type. EM-Mantel test is a good alternative for measuring phylogenetic signal in binary and categorical traits and for datasets with multiple traits. 相似文献
997.
Increased light‐use efficiency sustains net primary productivity of shaded coffee plants in agroforestry system 下载免费PDF全文
Fabien Charbonnier Olivier Roupsard Guerric le Maire Joannès Guillemot Fernando Casanoves André Lacointe Philippe Vaast Clémentine Allinne Louise Audebert Aurélie Cambou Anne Clément‐Vidal Elsa Defrenet Remko A. Duursma Laura Jarri Christophe Jourdan Emmanuelle Khac Patricia Leandro Belinda E. Medlyn Laurent Saint‐André Philippe Thaler Karel Van Den Meersche Alejandra Barquero Aguilar Peter Lehner Erwin Dreyer 《Plant, cell & environment》2017,40(8):1592-1608
In agroforestry systems, shade trees strongly affect the physiology of the undergrown crop. However, a major paradigm is that the reduction in absorbed photosynthetically active radiation is, to a certain extent, compensated by an increase in light‐use efficiency, thereby reducing the difference in net primary productivity between shaded and non‐shaded plants. Due to the large spatial heterogeneity in agroforestry systems and the lack of appropriate tools, the combined effects of such variables have seldom been analysed, even though they may help understand physiological processes underlying yield dynamics. In this study, we monitored net primary productivity, during two years, on scales ranging from individual coffee plants to the entire plot. Absorbed radiation was mapped with a 3D model (MAESPA). Light‐use efficiency and net assimilation rate were derived for each coffee plant individually. We found that although irradiance was reduced by 60% below crowns of shade trees, coffee light‐use efficiency increased by 50%, leaving net primary productivity fairly stable across all shade levels. Variability of aboveground net primary productivity of coffee plants was caused primarily by the age of the plants and by intraspecific competition among them (drivers usually overlooked in the agroforestry literature) rather than by the presence of shade trees. 相似文献
998.
Species turnover in Amazonian frogs: low predictability and large differences among forests 下载免费PDF全文
Youszef O.C. Bitar Hanna Tuomisto Leandra C. Pinheiro Leandro Juen Maria C. Santos‐Costa 《Biotropica》2017,49(5):695-705
The factors explaining species turnover at different spatial scales have been intensively studied, but most work in Amazonia has mainly focused on plants. For animals, it is not as obvious which environmental variables most affect differences in species composition among sites. We sought to identify what causes anuran turnover in Amazonian terra firme forests, and how the effectiveness of these factors varies among regions and across spatial scales. We sampled frogs in 56 plots along ponds and streams distributed over three terra firme forest areas in Eastern Amazonia. Using multiple regressions on distance matrices, we partitioned the variation in species turnover into components explained by variation in environmental and spatial distances. This was done in parallel for each area separately, and for all areas together, to assess the consistency of results between scales and across areas at the same scale. Each community seemed to respond to a set of factors specific to that area, and the identity of the variables that emerged as significant differed among areas and scales. Both geographical distances and environmental differences had larger explanatory power at the regional scale than at the local scale. The large differences among results from different areas caution against making broad generalizations about species turnover patterns from a single community, as real differences may exist among areas. 相似文献
999.
Robson Xavier Faria André Luis Almeida Souza Barbara Lima Luis Armando Candido Tietbohl Caio Pinho Fernandes Raquel Rodrigues Amaral Bettina Monika Ruppelt Marcelo Guerra Santos Leandro Rocha 《Journal of bioenergetics and biomembranes》2017,49(6):473-483
Chagas disease is caused by the Trypanosoma cruzi affecting millions of people, and widespread throughout Latin America. This disease exhibits a problematic chemotherapy. Benznidazole, which is the drug currently used as standard treatment, lamentably evokes several adverse reactions. Among other options, natural products have been tested to discover a novel therapeutic drug for this disease. A lot of plants from the Brazilian flora did not contain studies about their biological effects. Restinga de Jurubatiba from Brazil is a sandbank ecosystem poorly studied in relation to plant biological activity. Thus, three plant species from Restinga de Jurubatiba were tested against in vitro antiprotozoal activity. Among six extracts obtained from leaves and stem parts and 2 essential oils derived from leave parts, only 3 extracts inhibited epimastigote proliferation. Substances present in the extracts with activity were isolated (quercetin, myricetin, and ursolic acid), and evaluated in relation to antiprotozoal activity against epimastigote Y and Dm28 Trypanosoma cruzi strains. All isolated substances were effective to reduce protozoal proliferation. Essentially, quercetin and myricetin did not cause mammalian cell toxicity. In summary, myricetin and quercetin molecule can be used as a scaffold to develop new effective drugs against Chagas’s disease. 相似文献
1000.
Juliana Mendes Campolina Carolina São Leandro Sigrist Jane Maria Faulstich de Paiva Andréa Oliveira Nunes Virgínia Aparecida da Silva Moris 《The International Journal of Life Cycle Assessment》2017,22(12):1957-1968