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HAL1 mediate salt adaptation in Arabidopsis thaliana   总被引:5,自引:0,他引:5  
INTRODUCTIONSalinity is a major environmental stress that isa substantial constraint to crop production both fordry land and irrigated agriculture. The detrimental impact of this stress is perpetuated and exacerbated by management practices used to facilitatehigh-output crop production. To overcome theselimitations and improve production efficiency in theface of a burgeoning world population, more salt tolerant crops must be developed. In contrast with traditional breeding, the direct ill…  相似文献   
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水生植物作为水生生态系统的主体, 对发挥水生生态系统的自维持、自循环功能有重要作用。研究通过相关资料的查阅, 建立上海地区乡土水生植物名录, 并对其科属组成、区系特征、生活型、生长型等进行统计分析。结果表明上海地区乡土水生植物共计35 科83 属160 种(含变种), 单属科、单种属的比例较高, 均达65%以上; 植物区系组成丰富、成分复杂, 以热带成分占优势, 达64.6%; 生活型以挺水植物为主, 沉水植物次之, 浮水植物最少; 生长型类型丰富, 以草本型、禾草型居多, 20 种生长型可进一步归为表征相似生态学特征和功能地位的6 个生长型组。在水生态恢复与水景观建设中, 仅有68.8%的景观水体有水生植物应用,且应用种类在2 种以下的占79.2%。乡土水生植物应用不足, 一半以上为观赏性强的外来物种, 应用频率较高的为挺水植物, 对具有良好净化效果的沉水植物重视不够。因此, 在水生态恢复与水景观建设中, 建议加强乡土水生植物资源的繁育栽培, 在充分利用乡土水生植物资源配置群落的基础上, 根据水质的富营养及基底状况, 通过不同生长型组水生植物的应用, 构建沉水-浮水-挺水植物群落复合体, 并通过近自然型护岸的营造, 形成水生-湿生复合生态系统。运用植被工程学的原理和方法, 采用生态浮岛、生态沉岛等技术营造水生植被, 将强人工化的水景观建成具生命的水生生态系统。    相似文献   
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绥宁河生态修复对粒径分级叶绿素a的影响   总被引:5,自引:1,他引:5  
通过对上海市的苏州河支流绥宁河治理段与非治理段水体叶绿素a分粒级分析,探讨了生态修复对水体粒径分级叶绿素a的影响.结果表明,非治理和对照以及治理采样点微型和微微型浮游植物叶绿素a占总叶绿素a的百分比均值分别为85.232、92.402和95.205%,其中微型浮游植物叶绿素a占总叶绿素a的百分比均值分别为78.460、87.943和87.211%,对全河叶绿素a的贡献平均为84.538%,是该水体叶绿素a生物量的最大贡献者;网采浮游植物对全河叶绿素a的贡献仅为9.054%.生态修复工程试验使网采浮游植物相对生物量减少,微型浮游植物相对生物量保持稳定,而微微型浮游植物相对生物量增多,对超微型浮游植物的影响不大,微型和微微型浮游植物对工程试验的反应最敏感.  相似文献   
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A new species of Sabellaria is described from the southeast coast of Brazil and compared with related species known from South or North America.  相似文献   
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Individual cell manipulation and targeting is of major interest in the field of diagnosis, phenotypic characterization and drug delivery. Lab-on-a-chip technologies open the possibility to work easily at the single cell level. We developed a dielectrophoretic microchip capable to trap and manipulate individual cells and microspheres. We targeted single cells with functionalized microspheres in a software-controlled way proving the efficiency and reliability of our chip. As an example, we demonstrate guided targeting and binding of cell lines expressing or not specific antigens with microspheres coated or not with the corresponding monoclonal antibodies.  相似文献   
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Declining populations of less than 250 mature individuals are symptomatic of many Critically Endangered cycads, which, globally, comprise the most threatened group of organisms as a result of collecting and habitat loss. Survival plans focus on law enforcement, reintroduction, and augmentation programmes using plants from the wild and botanical gardens. Augmentation is one of the few remaining options for cycad populations, although the assumed benefits remain untested and there is a possibility that augmentation from different sources could compromise the genetic integrity of existing populations, especially when garden plants have no provenance data. We studied Encephalartos latifrons, a South African endemic, which is a typical Critically Endangered cycad. We studied the extent and structure of genetic diversity in wild and ex situ populations to assess the potential benefits and risks associated with augmentation programmes. We examined 86 plants using amplified fragment length polymorphisms (AFLPs). The 417 AFLP markers thus generated yielded a unique DNA ‘fingerprint’ for each plant. Wild populations retain high levels of genetic diversity and this is reflected among the ex situ holdings at the Kirstenbosch Botanical Garden. No population differentiation is evident, indicating a single panmictic population, consistent with moderately high levels of gene flow between subpopulations and a sexual mode of reproduction. Bayesian clustering identified four genotype groups in the wild, as well as a genotype group only found in ex situ collections. Our results indicate that E. latifrons would benefit from augmentation programmes, including the use of undocumented collections, and careful management of breeding plants would increase the heterogeneity of propagules. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105 , 293–308.  相似文献   
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A series of ester derivatives of annulated tetrahydroazocines, namely 2,3,6,11-tetrahydro-1H-azocino[4,5-b]indoles (5-10), 2,3,6,7-tetrahydro-1H-azocino[5,4-b]indoles (11-14), and 4,7,8,9-tetrahydro-1H-pyrrolo[2,3-d]azocines (15-18), synthesized through an efficient 6-->8 membered ring expansion procedure, were investigated for their acetylcholinesterase (AChE) inhibitory activities. Most of the compounds acted as AChE inhibitors in vitro, with IC(50) values ranging from 5 to 40 microM. The most potent compounds 11 and 15, both as racemic mixtures, proved selective toward AChE, exhibiting selectivity ratios versus butyrylcholinesterase (BuChE) of ca. 15 and more than 20, respectively. Structure-activity studies highlighted, among other factors, lipophilicity as a property modulating the AChE inhibition potency, as shown by a reasonable parabolic correlation between pIC(50) and experimental 1-octanol/water partition coefficient (logP), which described the prevailing behavior of the examined compounds (r(2)=0.665). Molecular docking simulations using the X-ray crystal structure of AChE from Torpedo californica suggested possible binding modes of the tetrahydroazocine ester derivatives 11 and 15.  相似文献   
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