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111.
Some protected species have benefited from human activities to a point where they sometimes raise concerns. However, gaps in knowledge about their human-related behaviour hamper effective management decisions. We studied non-breeding common ravens Corvus corax that aggregated and predated livestock in the surroundings of a landfill. Combining several approaches, we first assessed the effectiveness of relocations at distances ranging from 20 to 240 km, and of one-time disturbance consisting in non-lethal shots performed at night roosts and at surrounding foraging areas during two consecutive evenings, in reducing ravens’ presence at the landfill. Then, we documented the spatial ecology of both relocated ravens and control ones (i.e. released in situ). Although the return probability widely varied with relocation distance and time after release, homing behaviour (87/102 relocated ravens marked with wing tags [85.3%] returned to the landfill in 3 years) prevented relocations from sustainably reducing the presence of ravens. Likewise, one-time disturbance only decreased ravens’ abundance during a few hours. These results could be related to the extensive movements of ravens equipped with GPS trackers. The total area occupied by control ravens reached 40,492 km2, i.e. 7.4% of the area of France and 21.7% of the French species distribution range. Individuals used smaller home ranges (min?=?84; max?=?1814 km2), consisting in a network of foraging areas and roosts that they visited. The daily and weekly turnover rates in the observed area of the landfill were high (on average 0.68?±?0.2 and 0.36?±?0.17, respectively) and the actual presence of ravens displayed strong seasonal variation. Hence, one-time/local management actions affected only a limited proportion of the population, partly explaining their small impact. Our study provides information needed to improve future management plans in a context of increasing ravens populations and conflicts with human activities.  相似文献   
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113.
In this paper, we consider that our experience of time (to come) depends on the emotions we feel when we imagine future pleasant or unpleasant events. A positive emotion such as relief or joy associated with a pleasant event that will happen in the future induces impatience. Impatience, in our context, implies that the experience of time up to the forthcoming event expands. A negative emotion such as grief or frustration associated with an unpleasant event that will happen in the future triggers anxiety. This will give the experience of time contraction. Time, therefore, is not exogeneously given to the individual and emotions, which link together events or situations, are a constitutive ingredient of the experience of time. Our theory can explain experimental evidence that people tend to prefer to perform painful actions earlier than pleasurable ones, contrary to the predictions yielded by the standard exponential discounting framework.  相似文献   
114.
New series of Huprine (12-amino-6,7,10,11-tetrahydro-7,11-methanocycloocta[b]quinolines) derivatives have been synthesized and their inhibiting activities toward recombinant human acetylcholinesterase (rh-AChE) are reported. We have synthesized two series of Huprine analogues; in the first one, the benzene ring of the quinoline moiety has been replaced by different heterocycles or electron-withdrawing or electron-donating substituted phenyl group. The second one has been designed in order to evaluate the influence of modification at position 12 where different short linkers have been introduced on the Huprine X, Y skeletons. All these molecules have been prepared from ethyl- or methyl-bicyclo[3.3.1]non-6-en-3-one via Friedländer reaction involving selected o-aminocyano aromatic compounds. The synthesis of two heterodimers based on these Huprines has been also reported. Activities from moderate to same range than the most active Huprines X and Y taken as references have been obtained, the most potent analogue being about three times less active than parent Huprines X and Y. Topologic data have been inferred from molecular dockings and variations of activity between the different linkers suggest future structural modifications for activity improvement.  相似文献   
115.
Abstract Aim: The aim of this study was to evaluate a new endodontic leakage measurement method. Materials and methods: Permeability was assessed measuring the gas flow passing through the root. Positive and negative tests were carried out to assess the validity of the method. We used glass capillaries for calibration (diameters of 15, 30, 40, 50 and 75 mum). The applicability of the method was assessed with human teeth using three sealing methods: GuttaFlow (GF) and a single cone; Pulp Canal Sealer (PCS) and a single cone; PCS and system B. Results: This method demonstrated to be highly reproducible as the standard deviation was approximately 1% on average with glass capillaries. Significantly higher leakage (p<0.05) was recorded for endodontic treatment with GF and single cone compared to PCS and single cone and PCS with system B. Conclusion: Gas permeability is quantitative, sensitive, non-destructive and reproducible and seems appropriate for endodontic tests. It would participate in the indirect comprehension of leakage phenomena.  相似文献   
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Bone sarcoma as a second malignancy is rare but highly fatal. The present knowledge about radiation-absorbed organ dose–response is insufficient to predict the risks induced by radiation therapy techniques. The objective of the present study was to assess the treatment-induced risk for bone sarcoma following a childhood cancer and particularly the related risk of radiotherapy. Therefore, a retrospective cohort of 4,171 survivors of a solid childhood cancer treated between 1942 and 1986 in France and Britain has been followed prospectively. We collected detailed information on treatments received during childhood cancer. Additionally, an innovative methodology has been developed to evaluate the dose–response relationship between bone sarcoma and radiation dose throughout this cohort. The median follow-up was 26 years, and 39 patients had developed bone sarcoma. It was found that the overall incidence was 45-fold higher [standardized incidence ratio 44.8, 95 % confidence interval (CI) 31.0–59.8] than expected from the general population, and the absolute excess risk was 35.1 per 100,000 person-years (95 % CI 24.0–47.1). The risk of bone sarcoma increased slowly up to a cumulative radiation organ absorbed dose of 15 Gy [hazard ratio (HR) = 8.2, 95 % CI 1.6–42.9] and then strongly increased for higher radiation doses (HR for 30 Gy or more 117.9, 95 % CI 36.5–380.6), compared with patients not treated with radiotherapy. A linear model with an excess relative risk per Gy of 1.77 (95 % CI 0.6213–5.935) provided a close fit to the data. These findings have important therapeutic implications: Lowering the radiation dose to the bones should reduce the incidence of secondary bone sarcomas. Other therapeutic solutions should be preferred to radiotherapy in bone sarcoma-sensitive areas.  相似文献   
118.

Background

Forming a new species through the merger of two or more divergent parent species is increasingly seen as a key phenomenon in the evolution of many biological systems. However, little is known about how expression of parental gene copies (homeologs) responds following genome merger. High throughput RNA sequencing now makes this analysis technically feasible, but tools to determine homeolog expression are still in their infancy.

Results

Here we present HyLiTE – a single-step analysis to obtain tables of homeolog expression in a hybrid or allopolyploid and its parent species directly from raw mRNA sequence files. By implementing on-the-fly detection of diagnostic parental polymorphisms, HyLiTE can perform SNP calling and read classification simultaneously, thus allowing HyLiTE to be run as parallelized code. HyLiTE accommodates any number of parent species, multiple data sources (including genomic DNA reads to improve SNP detection), and implements a statistical framework optimized for genes with low to moderate expression.

Conclusions

HyLiTE is a flexible and easy-to-use program designed for bench biologists to explore patterns of gene expression following genome merger. HyLiTE offers practical advantages over manual methods and existing programs, has been designed to accommodate a wide range of genome merger systems, can identify SNPs that arose following genome merger, and offers accurate performance on non-model organisms.

Electronic supplementary material

The online version of this article (doi:10.1186/s12859-014-0433-8) contains supplementary material, which is available to authorized users.  相似文献   
119.
Embedded into the wall of collecting lymphatic vessels and trunks, the lymphatic smooth muscles are cardinal to the functions of the lymphatic system. Their intrinsic contractile property--the intrinsic lymph pump--through rhythmical and phasic contractions of the vessels, represents the principal mechanism by which lymph flow is generated. Through changes in tonic constrictions, lymphatic smooth muscles also modulate lymph flow resistance. Lymphatic smooth muscles are sensitive to physical and chemical stimuli, mediating changes in their activity and modulating lymphatic drainage. Because lymphatic smooth muscles play such an important role in fluid transport, their dysfunction may be a component of many inflammatory disease states. This review presents recent findings on the physiology and cellular biology of lymphatic smooth muscles and discusses the importance of these cells for the function of the lymphatic system in physiological and pathophysiological situations.  相似文献   
120.
Genome-scale metabolic models bridge the gap between genome-derived biochemical information and metabolic phenotypes in a principled manner, providing a solid interpretative framework for experimental data related to metabolic states, and enabling simple in silico experiments with whole-cell metabolism. Models have been reconstructed for almost 20 bacterial species, so far mainly through expert curation efforts integrating information from the literature with genome annotation. A wide variety of computational methods exploiting metabolic models have been developed and applied to bacteria, yielding valuable insights into bacterial metabolism and evolution, and providing a sound basis for computer-assisted design in metabolic engineering. Recent advances in computational systems biology and high-throughput experimental technologies pave the way for the systematic reconstruction of metabolic models from genomes of new species, and a corresponding expansion of the scope of their applications. In this review, we provide an introduction to the key ideas of metabolic modeling, survey the methods, and resources that enable model reconstruction and refinement, and chart applications to the investigation of global properties of metabolic systems, the interpretation of experimental results, and the re-engineering of their biochemical capabilities.  相似文献   
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