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1.
Yohannes M. S. Samosir Steve Adkins 《In vitro cellular & developmental biology. Plant》2014,50(4):493-501
An in vitro photoautotrophic step based on the supply of CO2-enriched air (1,600 μmol mol?1) during the light phase and ambient air (350 μmol mol?1 CO2) during the dark phase has been used to promote the ex vitro establishment of coconut (Cocos nucifera L.) seedlings. The introduction of this step into a previously developed in vitro protocol was found to improve the quality of the seedlings (as assessed by fresh weight increase, physical stature, leaf area and thickness, stomatal density, and chlorophyll a content, and primary and secondary root production), the proportion of seedlings successfully transferred to soil (improvement from 40% to 100%) and achieved in a shorter time (reduction from 10 to 6 mo). Best results using this photoautotrophic growth step were obtained when a low medium concentration of sucrose (43.8 mM or lower) was used, when it was applied to seedlings that had already reached 4 or 5 mo of age in the in vitro culture step, and when seedlings were cultured in the photoautotrophic system for 2 mo or more before transfer to soil. Our improved protocol is more efficient and it reduces the cost per plant for the international exchange of coconut germplasm. 相似文献
2.
Daren Lee Seth Ruffins Queenie Ng Nikhil Sane Steve Anderson Arthur Toga 《BMC bioinformatics》2010,11(1):608
Background
Digital atlases provide a common semantic and spatial coordinate system that can be leveraged to compare, contrast, and correlate data from disparate sources. As the quality and amount of biological data continues to advance and grow, searching, referencing, and comparing this data with a researcher's own data is essential. However, the integration process is cumbersome and time-consuming due to misaligned data, implicitly defined associations, and incompatible data sources. This work addressing these challenges by providing a unified and adaptable environment to accelerate the workflow to gather, align, and analyze the data. 相似文献3.
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5.
Sam Mavandadi Steve Feng Frank Yu Stoyan Dimitrov Karin Nielsen-Saines William R. Prescott Aydogan Ozcan 《PloS one》2012,7(10)
We propose a methodology for digitally fusing diagnostic decisions made by multiple medical experts in order to improve accuracy of diagnosis. Toward this goal, we report an experimental study involving nine experts, where each one was given more than 8,000 digital microscopic images of individual human red blood cells and asked to identify malaria infected cells. The results of this experiment reveal that even highly trained medical experts are not always self-consistent in their diagnostic decisions and that there exists a fair level of disagreement among experts, even for binary decisions (i.e., infected vs. uninfected). To tackle this general medical diagnosis problem, we propose a probabilistic algorithm to fuse the decisions made by trained medical experts to robustly achieve higher levels of accuracy when compared to individual experts making such decisions. By modelling the decisions of experts as a three component mixture model and solving for the underlying parameters using the Expectation Maximisation algorithm, we demonstrate the efficacy of our approach which significantly improves the overall diagnostic accuracy of malaria infected cells. Additionally, we present a mathematical framework for performing ‘slide-level’ diagnosis by using individual ‘cell-level’ diagnosis data, shedding more light on the statistical rules that should govern the routine practice in examination of e.g., thin blood smear samples. This framework could be generalized for various other tele-pathology needs, and can be used by trained experts within an efficient tele-medicine platform. 相似文献
6.
Matthew Westover Jared Baxter Rick Baxter Casey Day Ryan Jensen Steve Petersen Randy Larsen 《PloS one》2016,11(5)
Greater sage-grouse populations have decreased steadily since European settlement in western North America. Reduced availability of brood-rearing habitat has been identified as a limiting factor for many populations. We used radio-telemetry to acquire locations of sage-grouse broods from 1998 to 2012 in Strawberry Valley, Utah. Using these locations and remotely-sensed NAIP (National Agricultural Imagery Program) imagery, we 1) determined which characteristics of brood-rearing habitat could be used in widely available, high resolution imagery 2) assessed the spatial extent at which sage-grouse selected brood-rearing habitat, and 3) created a predictive habitat model to identify areas of preferred brood-rearing habitat. We used AIC model selection to evaluate support for a list of variables derived from remotely-sensed imagery. We examined the relationship of these explanatory variables at three spatial extents (45, 200, and 795 meter radii). Our top model included 10 variables (percent shrub, percent grass, percent tree, percent paved road, percent riparian, meters of sage/tree edge, meters of riparian/tree edge, distance to tree, distance to transmission lines, and distance to permanent structures). Variables from each spatial extent were represented in our top model with the majority being associated with the larger (795 meter) spatial extent. When applied to our study area, our top model predicted 75% of naïve brood locations suggesting reasonable success using this method and widely available NAIP imagery. We encourage application of our methodology to other sage-grouse populations and species of conservation concern. 相似文献
7.
Frank H. Gleason Steve K. Schmidt Agostina V. Marano 《Extremophiles : life under extreme conditions》2010,14(5):417-425
Zoosporic true fungi are thought to be ubiquitous in many ecosystems, especially in cool, moist soils and freshwater habitats
which are rich in organic matter. However, some of the habitats where these fungi are found may periodically experience extreme
conditions, such as soils in extremely dry, hot and cold climates, acidic and alkaline soils, polluted rivers, anaerobic soil
and water, saline soil and water, periglacial soils, oligotrophic soils, tree canopies and hydrothermal vents. It is clear
that many ecotypes of zoosporic true fungi have indeed adapted to extreme or stressful environmental conditions. This conclusion
is supported by studies in both the field and in the laboratory. Therefore, in our opinion, at least some true zoosporic fungi
can be considered to be extremophiles. 相似文献
8.
Steve E. Bellan 《PloS one》2010,5(4)
Nearly all mathematical models of vector-borne diseases have assumed that vectors die at constant rates. However, recent empirical research suggests that mosquito mortality rates are frequently age dependent. This work develops a simple mathematical model to assess how relaxing the classical assumption of constant mortality affects the predicted effectiveness of anti-vectorial interventions. The effectiveness of mosquito control when mosquitoes die at age dependent rates was also compared across different extrinsic incubation periods. Compared to a more realistic age dependent model, constant mortality models overestimated the sensitivity of disease transmission to interventions that reduce mosquito survival. Interventions that reduce mosquito survival were also found to be slightly less effective when implemented in systems with shorter EIPs. Future transmission models that examine anti-vectorial interventions should incorporate realistic age dependent mortality rates. 相似文献
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10.
Host tree resistance against the polyphagous wood-boring beetle Anoplophora glabripennis 总被引:2,自引:0,他引:2
W.D. Morewood K. Hoover P.R. Neiner J.R. McNeil & J.C. Sellmer 《Entomologia Experimentalis et Applicata》2004,110(1):79-86
Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae: Lamiini) is an invasive wood‐boring beetle with an unusually broad host range and a proven ability to increase its host range as it colonizes new areas and encounters new tree species. The beetle is native to eastern Asia and has become an invasive pest in North America and Europe, stimulating interest in delineating host and non‐host tree species more clearly. When offered a choice among four species of living trees in a greenhouse, adult A. glabripennis fed more on golden‐rain tree (Koelreuteria paniculata Laxmann) and river birch (Betula nigra L.) than on London planetree (Platanus × acerifolia (Aiton) Willdenow) or callery pear (Pyrus calleryana Decaisne). Oviposition rate was highest in golden‐rain tree, but larval mortality was also high and larval growth was slowest in this tree species. Oviposition rate was lowest in callery pear, and larvae failed to survive in this tree species, whether they eclosed from eggs laid in the trees or were manually inserted into the trees. Adult beetles feeding on callery pear had a reduced longevity and females feeding only on callery pear failed to develop any eggs. The resistance of golden‐rain tree against the larvae appears to operate primarily through the physical mechanism of abundant sap flow. The resistance of callery pear against both larvae and adults appears to operate through the chemical composition of the tree, which may include compounds that are toxic or which otherwise interfere with normal growth and development of the beetle. Unlike river birch or London planetree, both golden‐rain tree and callery pear are present in the native range of A. glabripennis and may therefore have developed resistance to the beetle by virtue of exposure to attack during their evolutionary history. 相似文献