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991.
Estimating geographical ranges of intra‐specific evolutionary lineages is crucial to the fields of biogeography, evolution, and biodiversity conservation. Models of isolation mechanisms often consider multiple distances in order to explain genetic divergence. Yet, the available methods to estimate the geographical ranges of lineages are based on direct geographical distances, neglecting other distance metrics that can better explain the spatial genetic structure. We extended the phylogeographical interpolation method (phylin ) in order to accommodate user‐defined distance metrics and to incorporate the uncertainty associated with genetic distance calculation. These new features were tested with simulated and empirical data sets. Multiple distance matrices were generated including geographical, resistance, and environmental distances to derive maps of lineage occurrence. The new additions to this method improved the ability to predict lineage occurrence, even with low sample size. We used a regression framework to quantify the relationship between the genetic divergence and competing distance matrices representing potential isolation processes that are subsequently used in the interpolation process. Including uncertainty in tree topology and the different distance matrices improved the robustness of the variograms, allowing a better fit of the theoretical model of spatial dependence. The improvements to the method increase its potential application in other fields. Accurately mapping genetic divergence can help to locate potential contact zones between lineages as well as barriers to gene flow, which has a broad interest in biogeographical and evolutionary studies. Additionally, conservation efforts could benefit from the integration of genetic variation and landscape features in a spatially explicit framework.  相似文献   
992.
993.
Anidulafungin is a new and very useful pharmacological tool for the treatment of invasive mycoses. The antifungal spectrum of anidulafungin reaches the most common pathogenic fungi. Anidulafungin is especially active against the genera Candida and Aspergillus. Its antifungal mechanism is based on the inhibition of the beta-1,3-D-glucan synthesis, an essential molecule for the cell wall architecture, with different consequences for Candida and Aspergillus, being anidulafungin fungicide for the former and fungistatic for the latter. This review describes the in vitro antifungal spectrum of anidulafungin based in the scientific and medical literature of recent years. We can underline that most than 99% of Candida isolates are susceptible to < or = 2 microg/ml of anidulafungin. MIC are very low (< or =0.125 microg/ml) for most clinical isolates of the species Candida albicans, Candida glabrata, Candida tropicalis and Candida krusei while Candida parapsilosis and Candida guilliermondii isolates are susceptible to anidulafungin concentrations < or = 2 microg/ml. An excellent activity of anidulafungin has been also described against Aspergillus, Pneumocystis and other fungi. However, its activity is very low against Cryptococcus and the Zygomycetes. The excellent activity of anidulafungin has made this antifungal a first line therapeutic indication for candidemia and invasive candidiasis in non-neutropenic patients.  相似文献   
994.
The behavior of the autonomous maize transposable element En/Spm of maize was studied in Arabidopsis. Transgenic Arabidopsis plants carrying En-1 elements were propagated for 12 generations using a single seed descent procedure. The distribution and activity of the En-1 element was monitored using Southern DNA hybridisations in generations 1, 6 and 12. In the first generation the highest number of En-1 insertions per line was 7, which increased to 20 in generation 12. The average number of En-1 insertions increased only slightly in the population, due to a gradual accumulation of segregants that lost the transposable element. During the development of the En-1 mutagenised population the element remained active even in the high-copy lines. In situ hybridisation demonstrated that multiple En-1 insertions were distributed over all Arabidopsis chromosomes. From the initial En-1 mutagenised populations many unstable gene mutations were recovered, indicating that En-1 can be used as a efficient tool for gene tagging in Arabidopsis.  相似文献   
995.
Cannabinoids, the active components of Cannabis sativa L., act in the body by mimicking endogenous substances—the endocannabinoids—that activate specific cell surface receptors. Cannabinoids exert various palliative effects in cancer patients. In addition, cannabinoids inhibit the growth of different types of tumor cells, including glioma cells, in laboratory animals. They do so by modulating key cell signaling pathways, mostly the endoplasmic reticulum stress response, thereby inducing antitumoral actions such as the apoptotic death of tumor cells and the inhibition of tumor angiogenesis. Of interest, cannabinoids seem to be selective antitumoral compounds, as they kill glioma cells, but not their non-transformed astroglial counterparts. On the basis of these preclinical findings, a pilot clinical study of Δ9-tetrahydrocannabinol (THC) in patients with recurrent glioblastoma multiforme has been recently run. The good safety profile of THC, together with its possible growth-inhibiting action on tumor cells, justifies the setting up of future trials aimed at evaluating the potential antitumoral activity of cannabinoids.  相似文献   
996.
To better understand the relation between coastal areas and their influence on social and economic conditions of municipalities, a set of indexes were developed to characterize coastal Mexico with an interdisciplinary approach. The composite of these bio-physical, social and economic indexes is referred to as an “integrated coastal orientation index”. Coastal characteristics should be taken into account in the coastal management policy formulation of a given region, and this index can be used to identify key areas for environmental protection or economic development at a national level. The results suggest that municipalities must manage their coastal jurisdictions, a large and diverse array of coastal space and ecosystems, medium to weak spatial demographics and settlement structures, infrastructure to improve quality of life, an overall low coastal population income, and various coastal activities. Spatial heterogeneity along the littoral zone in the coastal orientation led us to conduct a state analysis. We discuss these values and identify five highly coastal-orientated states in the extremes of the country. The development of this tool could help to pin-point different types of key areas within the regions studied and provide a tool to guide regional priorities. As an example, using a combination of extreme values of bio-physical, social and economic indexes was used to identify specific municipalities as candidates for environmental protection and others as areas where development can continue. Choices of indexes are discussed, and the relative importance given to each component of the coastal orientation (rather bio-physical, social and/or economic) will define the course of the coast's development and its sustainability.  相似文献   
997.
The lethality neutralization assay performed in mice is the standard recommended by the World Health Organization to estimate antivenom potency. The interpretation of its results without considering its analytical capacity may lead to erroneous conclusions. Therefore, laboratories that manufacture or control antivenoms must demonstrate the appropriateness of their models. A study of the method used at Instituto Clodomiro Picado, Costa Rica, to estimate the potency of antivenoms against Bothrops asper snake venom was performed. Results show that venom doses ranging from 2 to 6 Median Lethal Doses (LD50) are appropriate to be used as challenge in this test. Variables such as the injection route, number of mice used per venom/antivenom level, and weight of the animals are critical in the estimation of the Median Effective Dose (ED50), whereas incubation time is not. The assay has an acceptable selectivity, linearity, and limits of detection and quantification. Accuracy of the lethality neutralization assay, expressed as percentage recovery, was between 71% and 127%. Intermediate precision, expressed as relative standard deviation, was ≤17%. It is concluded that the analytical characteristics of this assay are adequate enough to prove product compliance and to have statistical control over an industrial line of antivenom serial production.  相似文献   
998.
999.
We test the hypotheses proposed by Gentry and Schnitzer that liana density and basal area in tropical forests vary negatively with mean annual precipitation (MAP) and positively with seasonality. Previous studies correlating liana abundance with these climatic variables have produced conflicting results, warranting a new analysis of drivers of liana abundance based on a different dataset. We compiled a pan-tropical dataset containing 28,953 lianas (≥2.5 cm diam.) from studies conducted at 13 Neotropical and 11 Paleotropical dry to wet lowland tropical forests. The ranges in MAP and dry season length (DSL) (number of months with mean rainfall <100 mm) represented by these datasets were 860–7250 mm/yr and 0–7 mo, respectively. Pan-tropically, liana density and basal area decreased significantly with increasing annual rainfall and increased with increasing DSL, supporting the hypotheses of Gentry and Schnitzer. Our results suggest that much of the variation in liana density and basal area in the tropics can be accounted for by the relatively simple metrics of MAP and DSL.  相似文献   
1000.
We studied the cranial postnatal ontogeny of Otaria byronia in order to detect sexual dimorphism in allometric terms, analyzing the rate of growth of functional variables linked to specific capacities as bite and head movements. We used 20 linear measurements to estimate allometric growth applying bivariate and multivariate analyses in females and males separately. Males were also analyzed in two partitioned subsets considering non-adult and adult stages, when the dimorphism is accentuated in order to reach optimal performance for intra-sexual competition. In the comparison of the employed techniques, we detected an empirical relationship between our multivariate results and the ordinary least square bivariate analysis. The quantitative analyses revealed different ontogenetic trajectories between non-adult and adult males in most variables, suggesting that the adult skull is not a scaled version of subadult skull. For instance, variables related with longitudinal dimensions decreased their allometric coefficients when the adult stage was reached, whereas those related with breadth or vertical dimensions increased their values. In adult males this could indicate that skull breadth and height are more important than longitudinal growth, relative to overall skull size. Conversely, inter-sexual comparisons showed that females and non-adult males shared similar ontogenetic growth trends, including more allometric trends than did males along their own ontogenetic trajectory. In general, adult males exhibited higher allometric coefficients than non-adult males in variables associated with bite and sexual behavior, whereas in comparison to females the latter showed higher coefficients values in these variables. Such patterns indicate a complex mode of growth in males beyond the growth extension, and are in partial agreement with changes previously reported for this and other species in the family Otariidae.  相似文献   
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