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981.
基于C/S、B/S集成的高校科研型实验室综合信息管理系统的设计与实现 总被引:2,自引:0,他引:2
分析高校科学研究型实验室管理的现状,成功开发出基于C/S、B/S结合模式、集成多种实验室管理相关模块的新型实验室集成信息管理系统(Laboratory Information Management Systems,LIMS)。系统以实验室为核心、对人员、仪器、试剂耗材及整体环境进行全方位的综合管理。其应用及推广,对进一步提高科研型实验室管理水平,提高仪器使用效率,合理利用资源具有重要意义。可满足高校研究型实验室集成化信息管理的新需要。 相似文献
982.
Rapamycin (RPM), a powerful agent used clinically in transplant recipients, induces CD4+CD25+ regulatory T cells (Tregs) which play an important role in induction of immune tolerance. However, long-term use of RPM has negative side effects. In this report, we found that combination with the low dose RPM and high dose IL-2 did not affect antigen presentation of rat B cells to Tregs, and could efficiently promote Tregs proliferation and enhance their inhibitory activities in vitro. In addition, the combination of low dose RPM and high dose IL-2 enhanced mRNA expression of Foxp3, TGF-β1 and Pim-2 in Tregs but not in CD4+CD25− T effector cells (Teffs). The Tregs inhibitory activity is positively associated with mRNA expressions of TGF-β1 and Pim-2 while unrelated to the Foxp3 mRNA expression. Our present study offers one approach to expand functional Tregs in vitro, which maybe used for clinical immune tolerance induction. 相似文献
983.
A critical role for sFRP proteins in maintaining caudal neural tube closure in mice via inhibition of BMP signaling 总被引:1,自引:0,他引:1
Kamana Misra 《Developmental biology》2010,337(1):74-167
Both the BMP and Wnt pathways have been implicated in directing aspects of dorsal neural tube closure and cell fate specification. However, the mechanisms that control the diverse responses to these signals are poorly understood. In this study, we provide genetic and functional evidence that the secreted sFRP1 and sFRP2 proteins, which have been primarily implicated as negative regulators of Wnt signaling, can also antagonize BMP signaling in the caudal neural tube and that this function is critical to maintain proper neural tube closure and dorsal cell fate segregation. Our studies thus reveal a novel role for specific sFRP proteins in balancing the response of cells to two critical extracellular signaling pathways. 相似文献
984.
985.
Carla Bardua Anne-Claire Fabre Margot Bon Kalpana Das Edward L. Stanley David C. Blackburn Anjali Goswami 《Evolution; international journal of organic evolution》2020,74(6):1200-1215
Evolutionary integration (covariation) of traits has long fascinated biologists because of its potential to elucidate factors that have shaped morphological evolution. Studies of tetrapod crania have identified patterns of evolutionary integration that reflect functional or developmental interactions among traits, but no studies to date have sampled widely across the species-rich lissamphibian order Anura (frogs). Frogs exhibit a vast range of cranial morphologies, life history strategies, and ecologies. Here, using high-density morphometrics we capture cranial morphology for 172 anuran species, sampling every extant family. We quantify the pattern of evolutionary modularity in the frog skull and compare patterns in taxa with different life history modes. Evolutionary changes across the anuran cranium are highly modular, with a well-integrated “suspensorium” involved in feeding. This pattern is strikingly similar to that identified for caecilian and salamander crania, suggesting replication of patterns of evolutionary integration across Lissamphibia. Surprisingly, possession of a feeding larval stage has no notable influence on cranial integration across frogs. However, late-ossifying bones exhibit higher integration than early-ossifying bones. Finally, anuran cranial modules show diverse morphological disparities, supporting the hypothesis that modular variation allows mosaic evolution of the cranium, but we find no consistent relationship between degree of within-module integration and disparity. 相似文献
986.
Margot Michaud Géraldine Veron Anne-Claire Fabre 《Evolution; international journal of organic evolution》2020,74(12):2681-2702
The skeleton is a complex arrangement of anatomical structures that covary to various degrees depending on both intrinsic and extrinsic factors. Among the Feliformia, many species are characterized by predator lifestyles providing a unique opportunity to investigate the impact of highly specialized hypercarnivorous diet on phenotypic integration and shape diversity. To do so, we compared the shape of the skull, mandible, humerus, and femur of species in relation to their feeding strategies (hypercarnivorous vs. generalist species) and prey preference (predators of small vs. large prey) using three-dimensional geometric morphometric techniques. Our results highlight different degrees of morphological integration in the Feliformia depending on the functional implication of the anatomical structure, with an overall higher covariation of structures in hypercarnivorous species. The skull and the forelimb are not integrated in generalist species, whereas they are integrated in hypercarnivores. These results can potentially be explained by the different feeding strategies of these species. Contrary to our expectations, hypercarnivores display a higher disparity for the skull than generalist species. This is probably due to the fact that a specialization toward high-meat diet could be achieved through various phenotypes. Finally, humeri and femora display shape variations depending on relative prey size preference. Large species feeding on large prey tend to have robust long bones due to higher biomechanical constraints. 相似文献
987.
Water, minerals, nutrients, etc., can be shared by physiological integration among inter-connected ramets of clonal plants. Nitrogen plays an important
role in alleviating cadmium (Cd) stress for clonal plants. But how different forms
of nitrogen affect growth performance of clonal plants subjected to heterogeneous
Cd stress still remains poorly understood. A pot experiment was conducted to
investigate the differential effects of ammonium and nitrate on growth performance of Glechoma longituba under heterogeneous Cd stress. In the experiment,
parent ramets of Glechoma longituba clonal fragments were respectively supplied
with modified Hoagland solution containing 7.5 mM ammonium, 7.5 mM nitrate
or the same volume of nutrient solution without nitrogen. Cd solution with different concentrations (0, 0.1 or 2.0 mM) was applied to offspring ramets of the clonal fragments. Compared with control (N-free), nitrogen addition to parent
ramets, especially ammonium, significantly improved antioxidant capacity [glutathione (GSH), proline (Pro), peroxidase (POD,) superoxide dismutase (SOD)
and catalase (CAT)], PSII activity [maximum quantum yield of PSII (Fv/Fm)
and effective quantum yield of PSII (ΦPSII)], chlorophyll content and biomass
accumulation of the offspring ramets suffering from Cd stress. In addition, negative effects of nitrate on growth performance of whole clonal fragments were
observed under Cd stress with high concentration (2.0 mM). Transportation or
sharing of nitrogen, especially ammonium, can improve growth performance of
clonal plants under heterogeneous Cd stress. The experiment provides insight
into transmission mechanism of nitrogen among ramets of clonal plants suffering
from heterogeneous nutrient supply. Physiological integration might be
an important ecological strategy for clonal plants adapting to heterogeneous
environment stress conditions. 相似文献
988.
The Society for Ecological Restoration (SER) Primer identifies key ecosystem attributes for evaluating restoration outcome. Broad attribute categories could be necessary due to the large variety of restoration projects, but could make overall evaluations and assessments challenging and might hamper the development of sound and successful restoration. In this study we carry out a systematic review of scientific papers addressing evaluation of restoration outcome. We include 104 studies published after 2010 from Europe or North America, representing different types of restoration projects in terrestrial and freshwater ecosystems. We explore the main ecological and socioeconomic attributes used to evaluate restoration outcome, and related indicators and specific methods applied to measure this, in relation to ecosystem and type of restoration project. We identify a wide range of indicators within each attribute, and show that very different methods are employed to measure them. This complexity reduces the opportunity for meaningful comparison and standardization of evaluation of restoration outcome, within and between ecosystems. Socioeconomic indicators are rarely used to evaluate restoration outcome, and studies including both ecological and socioeconomic indicators are nearly absent. Based on our findings we discuss whether standardization and streamlining of indicators is useful to improve the evaluation of “on the ground” restoration, or if this is not appropriate given the diversity of goals and ecosystems involved. Species‐specific traits are used in many projects and should be considered as an addition to the original SER attributes. Furthermore, we discuss the potential for restoration evaluation that encompasses not only assessment of ecological but also socioeconomic indicators. 相似文献
989.
990.
Predators can shape genetic correlations in prey by altering prey perception of risk. We manipulated perceived risk to test whether such non‐consumptive effects tightened behavioural trait correlations in wild‐caught stickleback from high‐ compared to low‐risk environments due to genetic variation in plasticity. We expected tighter genetic correlations within perceived risk treatments than across them, and tighter genetic correlations in high‐risk than in low‐risk treatments. We identified genetic variation in plasticity, with genetic correlations between boldness, sociality, and antipredator morphology, as expected, being tighter within treatments than across them, for both of two populations. By contrast, genetic correlations did not tighten with exposure to risk. Tighter phenotypic correlations in wild stickleback may thus arise because predators induce correlational selection on environmental components of these traits, or because predators tighten residual correlations by causing environmental heterogeneity that is controlled in the laboratory. Our study places phenotypic integration firmly into an ecological context. 相似文献