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The growing demand for native seeds in ecological restoration and rehabilitation, whether for mining, forest, or ecosystem restoration, has resulted in a major global industry in the sourcing, supply, and sale of native seeds. However, there are no international guidance documents for ensuring that native seeds have the same standards of quality assurance that are regular practice in the crop and horticultural industries. Using the International Principles and Standards for the Practice of Ecological Restoration as a foundation document, we provide for the first time a synthesis of general practices in the native seed supply chain to derive the Principles and Standards for Native Seeds in Ecological Restoration (“Standards”). These practices and the underpinning science provide the basis for developing quality measures and guidance statements that are adaptable at the local, biome, or national scale. Importantly, these Standards define what is considered native seed in ecological restoration and highlight the differences between native seeds versus seeds of improved genetics. Seed testing approaches are provided within a logical framework that outline the many different dormancy states in native seed that can confound restoration outcomes. A “pro‐forma” template for a production label is included as a practical tool that can be customized for local needs and to standardize reporting to end‐users on the level of seed quality and germinability to be expected in a native seed batch. These Standards are not intended to be mandatory; however, the guidance statements provide the foundation upon which regulatory approaches can be developed by constituencies and jurisdictions.  相似文献   
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From 50 to 90% of wild plant species worldwide produce seeds that are dormant upon maturity, with specific dormancy traits driven by species' occurrence geography, growth form, and genetic factors. While dormancy is a beneficial adaptation for intact natural systems, it can limit plant recruitment in restoration scenarios because seeds may take several seasons to lose dormancy and consequently show low or erratic germination. During this time, seed predation, weed competition, soil erosion, and seed viability loss can lead to plant re‐establishment failure. Understanding and considering seed dormancy and germination traits in restoration planning are thus critical to ensuring effective seed management and seed use efficiency. There are five known dormancy classes (physiological, physical, combinational, morphological, and morphophysiological), each requiring specific cues to alleviate dormancy and enable germination. The dormancy status of a seed can be determined through a series of simple steps that account for initial seed quality and assess germination across a range of environmental conditions. In this article, we outline the steps of the dormancy classification process and the various corresponding methodologies for ex situ dormancy alleviation. We also highlight the importance of record‐keeping and reporting of seed accession information (e.g. geographic coordinates of the seed collection location, cleaning and quality information, storage conditions, and dormancy testing data) to ensure that these factors are adequately considered in restoration planning.  相似文献   
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Wetland environment and habitat loss increase the rate of biodiversity decline and affect our ecosystems. Yancheng National Nature Reserve (YNNR) is a protected area dedicated to endangered migratory bird species to overwinter. However, it currently has a record low influx of migrating birds and might therefore be losing its founding purpose. We used remote sensing technology to assess and quantify the impacts and effects of invasive halophytes Spartina alterniflora in the habitat loss and shrinkage of endangered bird wintering habitat from 2003 to 2018. We also attempted to ascertain the causes and triggers of avian population decline and its relationship with habitat loss, as these phenomena threaten and endanger species both locally and globally. Our study shows how YNNR has lost about 80% of migratory bird habitat to invasive S. alterniflora and Phragmites australis, a native halophyte plant in the reserve. Furthermore, shoreline erosion triggered the retraction of S. alterniflora and its backward growth toward Suaeda Salsa, the preferred foraging habitat for migratory birds in the zone, which is a possible cause of their decline.  相似文献   
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Plant and Soil - In water-limited areas, shrubs influence biological soil crust (biocrust) composition and diversity via soil microenvironment alterations and through modifying biotic interactions...  相似文献   
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Malaria represents a major public health problem in Africa. In the East African highlands, the high-altitude areas were previously considered too cold to support vector population and parasite transmission, rendering the region particularly prone to epidemic malaria due to the lack of protective immunity of the population. Since the 1980’s, frequent malaria epidemics have been reported and these successive outbreaks may have generated some immunity against Plasmodium falciparum amongst the highland residents. Serological studies reveal indirect evidence of human exposure to the parasite, and can reliably assess prevalence of exposure and transmission intensity in an endemic area. However, the vast majority of serological studies of malaria have been, hereto, limited to a small number of the parasite’s antigens. We surveyed and compared the antibody response profiles of age-stratified sera from residents of two endemic areas in the western Kenyan highlands with differing malaria transmission intensities, during two distinct seasons, against 854 polypeptides of P. falciparum using high-throughput proteomic microarray technology. We identified 107 proteins as serum antibody targets, which were then characterized for their gene ontology biological process and cellular component of the parasite, and showed significant enrichment for categories related to immune evasion, pathogenesis and expression on the host’s cell and parasite’s surface. Additionally, we calculated age-fitted annual seroconversion rates for the immunogenic proteins, and contrasted the age-dependent antibody acquisition for those antigens between the two sampling sites. We observed highly immunogenic antigens that produce stable antibody responses from early age in both sites, as well as less immunogenic proteins that require repeated exposure for stable responses to develop and produce different seroconversion rates between sites. We propose that a combination of highly and less immunogenic proteins could be used in serological surveys to detect differences in malaria transmission levels, distinguishing sites of unstable and stable transmission.  相似文献   
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Highlights? Snx3 is highly expressed in vertebrate hematopoietic tissues ? Silencing of Snx3 results in anemia and hemoglobin defects in vertebrates ? Snx3 and Vps35 physically interact with Tfrc ? Snx3 is required for endosomal recycling of Tf-Tfrc complex  相似文献   
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