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First Report of Black Leaf Spot Caused by Alternaria alternata on Ramie in China 总被引:1,自引:0,他引:1 下载免费PDF全文
Yongting Yu Liangbin Zeng Lili Huang Zhun Yan Kai Sun Taotao Zhu Aiguo Zhu 《Journal of Phytopathology》2016,164(5):358-361
In 2012 and 2013, black leaf spot disease was observed on ramie plants in Hunan and Hubei Provinces, China. In the field, the symptoms of this disease included dark green to black big spots on leaves, often resulting in upwardly curled leaf margins. The pathogen isolates were identified as Alternaria alternata (Fr.) Keissler on the basis of morphology and sequence similarity of 99–100% to the published data for internal transcribed spacer (ITS), and glyceraldehyde‐3‐phosphate dehydrogenase (gdp). To our knowledge, this is the first report of Alternaria leaf spot of ramie in China. 相似文献
995.
Effects of experimental warming on plant reproductive phenology in Xizang alpine meadow北大核心CSCD 下载免费PDF全文
Aims: Climate warming strongly influences reproductive phenology of plants in alpine and arctic ecosystems. Here we focus on phenological shifts caused by warming in a typical alpine meadow on the Qinghai-Xizang Plateau. Our objective was to explore phenological responses of alpine plant species to experimental warming. Methods: Passive warming was achieved using open-top chambers (OTCs). The treatments included control (C), and four levels of warming (T1, T2, T3, T4). We selected Kobresia pygmaea, Potentilla saundersiana, Potentilla cuneata, Stipa purpurea, Festuca coelestis and Youngia simulatrix as the focal species. Plant phenology was scored every 3-5 days in the growing season. The reproductive phenology phases of each species were estimated through fitting the phenological scores to the Richards function. Important findings: Under soil water stress caused by warming, most plants in the alpine meadow advanced or delayed their reproductive events. As a result, warming significantly delayed phenological development of K. pygmaea. Warming significantly advanced reproductive phenology of P. saundersiana, S. purpurea and F. coelestis, but not of P. cuneata and Y. simulatrix. In addition, warming significantly shortened the average flowering duration of alpine plant species. The potentially warmer and drier growing seasons under climate change may shift the reproductive phenology of the alpine systems in similar pattern. 相似文献
996.
High-level phenotypic variations in populations of Armeniaca sibirica in Nei Mongol,China北大核心CSCD 下载免费PDF全文
Yin M.-Y.Jiang Z.-M.Zhu X.-C.Bao W.-Q.Zhao H.Wuyun T. 《植物生态学报》2016,(10):1090-1099
Aims: Our objectives were to determine the variations in phenotypic traits of Armeniaca sibirica populations and their spatial patterns. Methods: We used nested variation, coefficient of variation, multi-comparison, correlation analysis and principal component analysis to analyze the 23 phenotypic traits for 130 individuals in 13 populations of A. sibirica. Important findings: The results showed that there were significant differences in phenotypic variations among and within populations. The variation was greater among populations (47.15%) than within population (16.43%). The mean phenotypic differentiation coefficient was 73.03% among populations, indicating the variance among populations being the main source of the phenotypic variation. The average variation coefficient of 23 traits ranged from 7.01% to 27.23%, with an average of 14.28%. The variation coefficient of nutlet was highest (15.67%), and the variation coefficient of fruit was smallest (12.11%). The phenotypic diversity is highest in Wanjiagou Tumotezuoqi and smallest in Horqin, Right Front Banner Chaersen. Longitude, mean annual precipitation and sunshine duration were significantly correlated with major traits of phenotypic. The 13 populations could be divided into four groups according to the principal component analysis. Leaf traits of Wula Mountain and nutlet traits of Archorchin Banner were significantly correlated with ecological and geographic factors. 相似文献
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The changes in climate can result in several environmental stress factors. Among these, ultraviolet- B (UV-B) and water-deficit have serious detrimental effects on plants at the physiological, morphological, and biochemical levels. Biological soil crusts (BSCs), formed by an association between soil particles and photosynthetic algae, cyanobacteria, lichens, and mosses in varying proportions, are a key functional feature of arid and semi-arid areas. In this study, Bryum argenteum, isolated from BSCs found in the Tengger Desert, China, was subjected to UV-B and water-deficit, singly and in combination, in a greenhouse for 10 days. The treatments consisted of four UV-B levels (2.75, 3.08, 3.25, and 3.41 W/m2) and two water application levels (well-watered and water-deficit). UV-B treatment and water-deficit singly caused a significant decrease in chlorophyll (Chl) fluorescence parameters, carotenoid (Car), total flavonoid contents, and a significant increase in MDA content. The combined application of UV-B and water-deficit produced significantly higher Chl fluorescence parameters, Chl, Car and total flavonoid contents, but reduced MDA content. These results suggest that water-deficit alleviates the negative effects on B. argenteum caused by enhanced UV-B radiation. Our results provide novel insights into understanding the relationships between BSCs and environmental factors, and supply a theoretical foundation for BSC assessment and protection in arid and semi-arid regions. 相似文献
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Feng Zhu Anil Kalra Tal Saif Zaihan Yang King H. Yang Albert I. King 《Computer methods in biomechanics and biomedical engineering》2016,19(10):1053-1059
Traumatic brain injury due to primary blast loading has become a signature injury in recent military conflicts and terrorist activities. Extensive experimental and computational investigations have been conducted to study the interrelationships between intracranial pressure response and intrinsic or ‘input’ parameters such as the head geometry and loading conditions. However, these relationships are very complicated and are usually implicit and ‘hidden’ in a large amount of simulation/test data. In this study, a data mining method is proposed to explore such underlying information from the numerical simulation results. The heads of different species are described as a highly simplified two-part (skull and brain) finite element model with varying geometric parameters. The parameters considered include peak incident pressure, skull thickness, brain radius and snout length. Their interrelationship and coupling effect are discovered by developing a decision tree based on the large simulation data-set. The results show that the proposed data-driven method is superior to the conventional linear regression method and is comparable to the nonlinear regression method. Considering its capability of exploring implicit information and the relatively simple relationships between response and input variables, the data mining method is considered to be a good tool for an in-depth understanding of the mechanisms of blast-induced brain injury. As a general method, this approach can also be applied to other nonlinear complex biomechanical systems. 相似文献
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MicroRNAs (miRNAs) are endogenous small noncoding RNA molecules that negatively regulate gene expression. Herein, we investigated a selective number of miRNAs for their expression in skin tissue of Liaoning Cashmere goat during hair follicle cycles, and their intracellular regulatory networks were constructed based on bioinformatics analysis. The relative expression of six miRNAs (mir-103-3p, -15b-5p, 17-5p, -200b, -25-3p, and -30c-5p) at anagen phase is significantly higher than that at catagen and/or telogen phases. In comparison to anagen, the relative expression of seven miRNAs (mir-148a-3p, -199a-3p, -199a-5p, -24-3p, -30a-5p, -30e-5p, and -29a-3p) was revealed to be significantly up-regulated at catagen and/or telogen stages. The network analyses of miRNAs indicated those miRNAs investigated might be directly or indirectly involved in several signaling pathways through their target genes. These results provided a foundation for further insight into the roles of these miRNAs in skin tissue of Liaoning Cashmere goat during hair follicle cycles. 相似文献
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