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991.
992.
Trichoderma longibrachiatum can be used for the control of Heterodera avenae in crops, but the effectiveness and possible mechanisms are unknown. Here we determined the efficacy and the mechanism responsible for the nematode control in spring wheat (Triticum aestivum L.). Wheat seedlings inoculated with T. longibrachiatum at the concentrations from 1.5 × 104 to 1.5 × 108 spores ml?1 significantly increased plant height, root length, and plant biomass; decreased H. avenae infection in both rhizospheric soil and roots; and enhanced chlorophyll content, root activity, and the specific activities of resistance-related enzymes (peroxidase, polyphenol oxidase and phenylalanine ammonia lyase), compared to the control. Those reactions occurred soon after T. longibrachiatum inoculation and the effect reached the maximum 7–9 days after inoculation. Promoting competitive plant growth and inducing enzyme-trigged resistance serve as the main mechanism responsible for T. longibrachiatum against H. avenae. T. longibrachiatum can be considered an effective biocontrol agent against H. avenae in wheat. 相似文献
993.
Journal of Plant Growth Regulation - To investigate the effects of red and blue light on potato growth and yield, potato plantlets were transplanted under white (W), red (R), blue (B), and... 相似文献
994.
995.
Syntaxin 16 (Syx16) is member of the soluble N‐ethylmaleimide sensitive factor attachment protein receptor (SNARE) family of molecules that functions in membrane fusion in eukaryotic cells. A rather ubiquitously expressed, tail‐anchored membrane protein localized mainly at the trans‐Golgi network (TGN), it mediates primarily retrograde endosomal‐TGN transport. In spite of its ubiquitous expression, Syx16 has specific and interesting roles in the physiology of specialized cells, including Glut4 dynamics, dendritic outgrowth‐related membrane traffic, and cytokinesis. We discussed these physiological functions of Syx16 in the light of what is known of its subcellular localization, vesicular trafficking pathways involved, cognate SNARE partners and other interacting proteins. Further, we speculate on some possible pathophysiological roles of Syx16. J. Cell. Physiol. 225: 326–332, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
996.
色季拉山急尖长苞冷杉种群不同龄级立木的空间分布格局 总被引:8,自引:4,他引:4
植物种群空间分布格局是种群个体在水平空间的分布、配置状况,是种群对环境适应的生存策略及适应机制的反映。以色季拉山急尖长苞冷杉(Abies georgei var.smithii)原始林为研究对象,在色季拉山东坡设置100 m×100 m固定样地,采用相邻网格法将样地划分为25个20 m×20 m的调查单元,对样地内所有基径≥0.1 cm的急尖长苞冷杉进行调查,记录林木的坐标、胸径、基径、冠幅等信息。依据基径和胸径两个指标将林木划分为12个径级和6个龄级(幼苗、幼树、小树、中树、大树、老树),对种群的径级特征及空间分布格局进行分析。结果显示:(1)急尖长苞冷杉种群在不同径级上的分布成倒"J"型。(2)种群整体、幼苗、幼树随空间尺度的增大依次呈现集群分布、随机分布和均匀分布,小树、中树、大树、老树在所研究尺度内均为随机分布。(3)幼树与幼苗在小尺度上接近或达到负关联,在中、大尺度无显著关联;小树、中树、大树、老树在空间分布上与幼苗、幼树的关联性符合Janzen-Connell假说,但小树、中树、大树、老树之间无显著关联。上述结果表明:色季拉山急尖长苞冷杉种群为稳定增长型种群,小径木以集群方式相互庇护以提高自身适应环境的能力,大径木在小、中尺度抑制林下更新,在大尺度则促进更新。该结果有助于揭示色季拉山急尖长苞冷杉种群的现状与动态规律,可为深入研究该种群维持机制提供理论依据。 相似文献
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998.
999.
Shengjie Liu Xiaobing Lin Jocelyn E. Behm Hao Yuan Petr Stiblik Jan obotník Jianmin Gan Shangwen Xia Xiaodong Yang 《Ecological Entomology》2019,44(6):762-770
1. While it is clear that land‐use change significantly impacts the taxonomic dimension of soil biodiversity, how the functional dimension responds to land‐use change is less well understood. 2. This study examined how the transformation of primary forests into rubber tree monocultures impacts individual termite species and how this change is reflected in termite taxonomic and functional α‐diversity (within site) and β‐diversity (among sites). 3. Overall, individual species responded strongly to land‐use change, whereby only 11 of the 27 species found were able to tolerate both habitats. These differences caused a 27% reduction in termite taxonomic richness and reduced taxonomic β‐diversity in rubber plantations compared with primary forests. The study also revealed that the forest conversion led to a shift in some termite species with smaller body size, shorter legs and smaller mandibular traits. Primary forests exhibited higher functional richness and functional β‐diversity of termite species, indicating that functional traits of termite species in rubber plantations are more evenly distributed. 4. The present study suggests that forest conversion does not merely decrease taxonomic diversity of termites, but also exerts functional trait filtering within some termite species. The results affirm the need for biodiversity assessments that combine taxonomic and functional indicators when monitoring the impact of land‐use change. 相似文献
1000.
黑线仓鼠肥满度的研究 总被引:10,自引:1,他引:9
1984—1989年,作者在呼和浩特地区野外捕获3008号黑线仓鼠标本进行了肥满度研究。结果表明,该鼠肥满度与栖息地和年龄无关,而有性别、季节和年度差异;肥满度年度变化与种群数量年度消长以及月均肥满度与月均捕获率的相关程度均未达到显著水平,说明该鼠的肥满度不能作为预测其种群数量的主要指标。 相似文献