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151.
Surface functionalization of nanobiomaterials for application in stem cell culture,tissue engineering,and regenerative medicine
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Deepti Rana Keerthana Ramasamy Maria Leena Constanza Jiménez Javier Campos Paula Ibarra Ziyad S. Haidar Murugan Ramalingam 《Biotechnology progress》2016,32(3):554-567
Stem cell‐based approaches offer great application potential in tissue engineering and regenerative medicine owing to their ability of sensing the microenvironment and respond accordingly (dynamic behavior). Recently, the combination of nanobiomaterials with stem cells has paved a great way for further exploration. Nanobiomaterials with engineered surfaces could mimic the native microenvironment to which the seeded stem cells could adhere and migrate. Surface functionalized nanobiomaterial‐based scaffolds could then be used to regulate or control the cellular functions to culture stem cells and regenerate damaged tissues or organs. Therefore, controlling the interactions between nanobiomaterials and stem cells is a critical factor. However, surface functionalization or modification techniques has provided an alternative approach for tailoring the nanobiomaterials surface in accordance to the physiological surrounding of a living cells; thereby, enhancing the structural and functional properties of the engineered tissues and organs. Currently, there are a variety of methods and technologies available to modify the surface of biomaterials according to the specific cell or tissue properties to be regenerated. This review highlights the trends in surface modification techniques for nanobiomaterials and the biological relevance in stem cell‐based tissue engineering and regenerative medicine. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:554–567, 2016 相似文献
152.
Arsenic toxicity: cell signalling and the attenuating effect of nitric oxide in Eichhornia crassipes
H. M. Andrade J. A. Oliveira F. S. Farnese C. Ribeiro A. A. Silva F. V. Campos J. L. Neto 《Biologia Plantarum》2016,60(1):173-180
Nitric oxide (NO) is an important molecule involved in the perception of stress induced by toxic compounds such as arsenic (As). The present study investigated the role of NO applied as sodium nitroprusside (SNP) in cell signalling and the ability of NO to attenuate the toxic effects of As (in the form of sodium arsenate) in water hyacinth (Eichhornia crassipes). Water hyacinth plants were collected and assigned to one of the following treatments: control; 100 μM SNP; 20 μM As; or 20 μM As + 100 μM SNP. The plants remained under these conditions for 0, 4, 12, and 24 h. After each time interval, the plants were collected and As absorption, production of reactive oxygen species (ROS), integrity of membranes, and antioxidant enzyme activities were evaluated. The plants were able to absorb and accumulate large amounts of As, even after only four hours of exposure to the pollutant. The absorption and bioaccumulation factor of As was even greater when plants were exposed to both As and SNP. The accumulation of As triggered increases in ROS production and cell membrane damage. In the presence of SNP, the tolerance index to As increased and damage was mitigated. Therefore, from the present work, it was possible to conclude that exogenous NO influenced the ability of plants to tolerate As; this finding has implications for phytoremediation in areas contaminated by As. 相似文献
153.
154.
Virtual reconstruction of the Early Pleistocene mandible ATD6‐96 from Gran Dolina‐TD6‐2 (Sierra De Atapuerca,Spain)
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155.
Frederic Bartumeus Daniel Campos William S. Ryu Roger Lloret‐Cabot Vicenç Méndez Jordi Catalan 《Ecology letters》2016,19(11):1299-1313
Understanding the structural complexity and the main drivers of animal search behaviour is pivotal to foraging ecology. Yet, the role of uncertainty as a generative mechanism of movement patterns is poorly understood. Novel insights from search theory suggest that organisms should collect and assess new information from the environment by producing complex exploratory strategies. Based on an extension of the first passage time theory, and using simple equations and simulations, we unveil the elementary heuristics behind search behaviour. In particular, we show that normal diffusion is not enough for determining optimal exploratory behaviour but anomalous diffusion is required. Searching organisms go through two critical sequential phases (approach and detection) and experience fundamental search tradeoffs that may limit their encounter rates. Using experimental data, we show that biological search includes elements not fully considered in contemporary physical search theory. In particular, the need to consider search movement as a non‐stationary process that brings the organism from one informational state to another. For example, the transition from remaining in an area to departing from it may occur through an exploratory state where cognitive search is challenged. Therefore, a more comprehensive view of foraging ecology requires including current perspectives about movement under uncertainty. 相似文献
156.
The tomato mutant ars1 (altered response to salt stress 1) identifies an R1‐type MYB transcription factor involved in stomatal closure under salt acclimation
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157.
158.
Vera Lucia Portal Melissa Medeiros Markoski Alexandre Schaan de Quadros Sílvia Garofallo Julia Lorenzon dos Santos Aline Oliveira Camila Wechenfelder Viviane Paiva de Campos Priscilla Azambuja Lopes de Souza Luana Machado Aline Marcadenti 《Trials》2016,17(1)
BackgroundCardiovascular disease has become a major health problem, and it has been associated with both environmental and genetic factors. Studies have shown that the Mediterranean Diet (MeDiet), or its components such as nuts and olive oil, may be strongly associated with the improvement of cardiovascular risk factors in specific populations. The purpose of the GENUTRI study is to investigate the interaction of genetics with cardiovascular risk factors in a non-Mediterranean population with coronary artery disease (CAD) according to three different diets: rich in pecan nuts, in extra-virgin olive oil or a control diet.Methods/designThe GENUTRI study is a single-center, randomized, open-label, parallel-group, 12-week pragmatic clinical trial conducted in patients aged 40 to 80 years and diagnosed with CAD. A standardized questionnaire will be applied to data collection and a blood sample will be obtained for lipid, glycemic and inflammatory profile evaluation. Polymorphisms in the CD36 and STAT3 genes will be detected using the TaqMan® SNP Genotyping Assay. Patients will be allocated in three groups: group 1: 30 g/day of pecan nuts; group 2: 30 ml/day of olive oil; and group 3: control diet. The primary outcome will consist of changes in LDL-cholesterol (in mg/dl) after 12 weeks of intervention.DiscussionStudies have shown the beneficial effects of diets rich in nuts and olive oil mainly in the Mediterranean population. GENUTRI is a clinical trial focusing on the effects of nuts or olive oil supplementation in Brazilian individuals. Additionally, we will try to demonstrate that genetic polymorphisms linked to cardiovascular disease may modulate the effects of different diets on biochemical and inflammatory markers among these subjects.
Trial registration
ClinicalTrials.gov Identifier: (registered on 18 July 2014: first version). NCT02202265相似文献159.
Diamondback moth performance and preference for leaves of Brassica oleracea of different ages and strata
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L. F. Moreira N. C. Teixeira N. A. Santos J. O. S. Valim R. M. Maurício R. N. C. Guedes M. G. A. Oliveira W. G. Campos 《Journal of Applied Entomology》2016,140(8):627-635
The preference–performance hypothesis predicts that moth behaviour links plant variations with caterpillar attack and distribution, and the plant‐age hypothesis states that specialist herbivores are more successful in exploring younger plant tissue. We integrated these predictions to investigate underlying mechanisms by which moths and caterpillars of Plutella xylostella L. (Lepidoptera: Plutellidae) track and exploit within‐plant variability of leaf age and stratification. We measured leaf proteins, glucosinolates and fibre, as well as larval choice, developmental performance, and moth oviposition preference with regard to leaf age classes (young, mature and senescent) of three varieties (collard, cauliflower and cabbage) of the main host plant Brassica oleracea L. Larvae consistently fit the prediction that specialist herbivores prefer and perform better on young, upper leaves that have the highest protein level, despite the highest content of defence compounds. Conversely, moths laid more eggs on fibrous and less nutritious leaves from the lower and senescent stratum. We argue that the leaf stratification of host plants imposes conflicting selective pressures concerning offspring feeding and protection on adult females. If egg mortality is catastrophic on the upper nutritious leaves in a particular microclimatic context (e.g. sun, heat, winds, drought or rain‐washing), then oviposition preference will remain for the suboptimal lower and senescent leaves. The ability of larvae to spread upwards over the plant to access the more nutritious leaf stratum is critical when eggs are preferentially laid on the protective low‐quality leaves. 相似文献
160.
João Paulo Oliveira Corrêa Camilo Elber Vital Marcos Vinícius Marques Pinheiro Diego Silva Batista Cleber Witt Saldanha Ana Cláudia Ferreira da Cruz Marcela Morato Notini Débora Márcia Silva Freitas Fábio Murilo DaMatta Wagner Campos Otoni 《In vitro cellular & developmental biology. Plant》2016,52(1):45-55