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1.
Eve Galimany Inke Sunila Hlne Hgaret Montserrat Ramn Gary H. Wikfors 《Harmful algae》2008,7(5):702-711
Mussels (Mytilus edulis) were exposed to cultures of the toxic dinoflagellate Alexandrium fundyense or the non-toxic alga Rhodomonas sp. to evaluate the effects of the harmful alga on the mussels and to study recovery after discontinuation of the A. fundyense exposure. Mussels were exposed for 9 days to the different algae and then all were fed Rhodomonas sp. for 6 more days. Samples of hemolymph for hemocyte analyses and tissues for histology were collected before the exposure and periodically during exposure and recovery periods.Mussels filtered and ingested both microalgal cultures, producing fecal pellets containing degraded, partially degraded, and intact cells of both algae. Mussels exposed to A. fundyense had an inflammatory response consisting of degranulation and diapedesis of hemocytes into the alimentary canal and, as the exposure continued, hemocyte migration into the connective tissue between the gonadal follicles. Evidence of lipid peroxidation, similar to the detoxification pathway described for various xenobiotics, was found; insoluble lipofuchsin granules formed (ceroidosis), and hemocytes carried the granules to the alimentary canal, thus eliminating putative dinoflagellate toxins in feces. As the number of circulating hemocytes in A. fundyense-exposed mussels became depleted, mussels were immunocompromised, and pathological changes followed, i.e., increased prevalences of ceroidosis and trematodes after 9 days of exposure. Moreover, the total number of pathological changes increased from the beginning of the exposure until the last day (day 9). After 6 days of the exposure, mussels in one of the three tanks exposed to A. fundyense mass spawned; these mussels showed more severe effects of the toxic algae than non-spawning mussels exposed to A. fundyense.No significant differences were found between the two treatments during the recovery period, indicating rapid homeostatic processes in tissues and circulating hemocytes. 相似文献
2.
Effect of Energy Under-Reporting on Secular Trends of Dietary Patterns in a Mediterranean Population
Anna N. Funtikova Santiago F. Gomez Montserrat Fitó Roberto Elosua Alejandra A. Benítez-Arciniega Helmut Schr?der 《PloS one》2015,10(5)
BackgroundDiet is an important factor in the prevention of chronic diseases. Analysis of secular trends of dietary patterns can be biased by energy under-reporting. Therefore, the objective of the present study was to analyse the impact of energy under-reporting on dietary patterns and secular trends in dietary patterns defined by cluster analysis.ResultsThree clusters, “healthy”, “mixed” and “western”, were identified for both surveys. The “mixed” cluster was the predominant cluster in both surveys. Excluding EUR reduced the proportion of the “mixed” cluster up to 6.40% in the 2000 survey; this caused secular trend increase in the prevalence of the “mixed” pattern. Cross-classification analysis of all participants and PER’ data showed substantial agreement in cluster assignments: 68.7% in 2000 and 84.4% in 2005. Excluding EUR did not cause meaningful (≥15%) changes in the “healthy” pattern. It provoked changes in consumption of some food groups in the “mixed” and “western” patterns: mainly decreases of unhealthy foods within the 2000 and increases of unhealthy foods within the 2005 surveys. Secular trend effects of EUR were similar to those within the 2005 survey. Excluding EUR reversed the direction of secular trends in consumption of several food groups in PER in the “mixed” and “western” patterns.ConclusionsEUR affected distribution of participants between dietary patterns within and between surveys, secular trends in food group consumption and amount of food consumed in all, but not in the “healthy” pattern. Our findings emphasize threats from energy under-reporting in dietary data analysis. 相似文献
3.
Umberto Melia Montserrat Vallverdú Xavier Borrat Jose Fernando Valencia Mathieu Jospin Erik Weber Jensen Pedro Gambus Pere Caminal 《PloS one》2015,10(4)
The level of sedation in patients undergoing medical procedures evolves continuously, affected by the interaction between the effect of the anesthetic and analgesic agents and the pain stimuli. The monitors of depth of anesthesia, based on the analysis of the electroencephalogram (EEG), have been progressively introduced into the daily practice to provide additional information about the state of the patient. However, the quantification of analgesia still remains an open problem. The purpose of this work is to improve the prediction of nociceptive responses with linear and non-linear measures calculated from EEG signal filtered in frequency bands higher than the traditional bands. Power spectral density and auto-mutual information function was applied in order to predict the presence or absence of the nociceptive responses to different stimuli during sedation in endoscopy procedure. The proposed measures exhibit better performances than the bispectral index (BIS). Values of prediction probability of Pk above 0.75 and percentages of sensitivity and specificity above 70% were achieved combining EEG measures from the traditional frequency bands and higher frequency bands. 相似文献
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Hem Nalini Morzaria-Luna Gabriela Cruz-Piñón Richard C. Brusca Ariadna Montserrat López-Ortiz Marcia Moreno-Báez Héctor Reyes-Bonilla Peggy Turk-Boyer 《Biodiversity and Conservation》2018,27(14):3819-3842
As marine systems are threatened by increasing human impacts, mechanisms to maintain biodiversity and ecosystem functions and services are needed. Protecting areas of conservation importance may serve as a proxy for maintaining these functions, while also facilitating efficient use and management of limited resources. Biodiversity hotspots have been used as surrogates for spatial conservation importance; however, as many protected areas have been established opportunistically and under differing criteria, it is unclear how well they actually protect hotspots. We evaluated how well the current protected area network and priority areas selected through previous systematic conservation planning exercises preserve biodiversity hotspots in the Gulf of California, Mexico. We also determined spatial congruence between biodiversity hotspots based on different criteria, which may determine their ability to be used as surrogates for each other. We focus on the Gulf of California because it is a megadiverse system where limited information regarding species diversity and distribution has constrained development of strategies for conservation and management. We developed a species occurrence database and identified biodiversity hotspots using four different criteria: species richness, rarity, endemism, and threatened species. We interpolated species occurrence, while accounting for heterogeneous sampling efforts. We then assessed overlap of hotspots with existing protected areas and priority areas, and between hotspots derived by distinct criteria. We gathered 286,533 occurrence records belonging to 12,105 unique species, including 6388 species identified as rare, 642 as endemic, and 386 as threatened. We found that biodiversity hotspots showed little spatial overlap with areas currently under protection and previously identified priority areas. Our results highlight the importance of distinct spatial areas of biodiversity and suggest that different ecological mechanisms sustain different aspects of diversity and multiple criteria should be used when defining conservation areas. 相似文献
7.
Reduced dopamine and glutamate neurotransmission in the nucleus accumbens of quinpirole‐sensitized rats hints at inhibitory D2 autoreceptor function 下载免费PDF全文
8.
Consistent performance of invasive plant species within and among islands of the Mediterranean basin
Anna Traveset Giuseppe Brundu Luisa Carta Irene Mprezetou Philip Lambdon Manuela Manca Frédéric Médail Eva Moragues Javier Rodríguez-Pérez Akis-Stavros D. Siamantziouras Carey M. Suehs Andreas Y. Troumbis Montserrat Vilà Philip E. Hulme 《Biological invasions》2008,10(6):847-858
Since the success of an invasive species depends not only upon its intrinsic traits but also on particular characteristics
of the recipient habitat, assessing the performance of an invader across habitats provides a more realistic analysis of risk.
Such an analysis will not only provide insights into the traits related to invasiveness, but also the habitat characteristics
that underpin vulnerability to invasion that, taken together, will facilitate the selection of management strategies to mitigate
the invader’s effect. In the present study, we considered the Mediterranean basin islands as an excellent study region to
test how the same invasive species perform in different habitats within a single island, and to scale up differences among
islands with similar climate. We tested how the performance of three widespread plant invaders with clonal growth but contrasting
life-history traits, a deciduous tree Ailanthus altissima, a succulent subshrub Carpobrotus spp., and an annual geophyte Oxalis pes-caprae, varied depending upon the species identity, habitat, and invaded island. The environmental parameters considered were habitat
type, elevation, species diversity in the invaded plot, and several soil traits (% C, % N, C/N, pH, and relative humidity).
The study documents that the performance of these three important and widespread plant invaders is dependent mainly on species
identity, and less upon the invaded island’s general features. Likewise, differences in performance among habitats were only
significant in the case of Ailanthus, whereas Carpobrotus and Oxalis appear to perform equally well in different environments. Ailanthus thus appears to have a broader spectrum of invasiveness, being able to invade a larger number of habitat types. On the contrary,
Carpobrotus spp. have not yet invaded habitats different from those where the species have been originally introduced and where they
are still commonly spread by humans. Oxalis distribution is mainly related to agricultural activities and disturbed sites, and the total area infested by this geophyte
may be more reflection of the extent of suitable habitats than of invasiveness or ecological impact. Our results confirm the
potential for these species to significantly alter the functioning of ecosystems in the Mediterranean islands and highlight
the risk to other islands not yet invaded. 相似文献
9.
F. Morales A. Abadía J. Abadía G. Montserrat E. Gil-Pelegrín 《Trees - Structure and Function》2002,16(7):504-510
Sun and shade leaves of two Mediterranean Quercus species, Quercus ilex subsp. ballota (Desf.) Samp. and Quercus coccifera L., were compared by measuring leaf optical properties, photosynthetic pigment composition and photosystem II efficiency. The presence of trichomes in the adaxial (upper) leaf surface of Q. ilex subsp. ballota seems to constitute an important morphological mechanism that allows this species to maintain a good photosystem II efficiency during the summer. Q. coccifera has almost no trichomes and seems instead to develop other physiological responses, including a smaller light-harvesting antenna size, higher concentrations of violaxanthin cycle pigments and a higher (zeaxanthin + antheraxanthin)/(violaxanthin + antheraxanthin + zeaxanthin) ratio. Q. coccifera was not able to maintain a good photosystem II efficiency up to the end of the summer. In Q. ilex subsp. ballota leaves, natural loss or mechanical removal of adaxial-face leaf trichomes induced short-term decreases in photosystem II efficiency. These changes were accompanied by de-epoxidation of violaxanthin cycle pigments, suggesting that the absence of trichomes would trigger physiological responses in this species. Our data have revealed different patterns of response of Q. ilex subsp. ballota and Q. coccifera facing the stress conditions prevailing in the Mediterranean area. 相似文献
10.
Laura Martin-Fernandez Andrey Ziyatdinov Marina Carrasco Juan Antonio Millon Angel Martinez-Perez Noelia Vilalta Helena Brunel Montserrat Font Anders Hamsten Juan Carlos Souto José Manuel Soria 《PloS one》2016,11(1)