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991.
Zusammenfassung Es wurde die Wirkung einer TSH-Injektion auf den Gehalt der Bernsteinsäuredehydrogenase und der SH-Gruppen in der Schilddrüse der Ratte untersucht. 4 h nach der Injektion von TSH erfolgte ein signifikanter Anstieg der Bernsteinsäuredehydrogenase und SH-Gruppen. Die Methode ist deshalb zur Untersuchung der Schilddrüsenaktivität im kurzfristigen Versuch geeignet.

Aided by a grant from the Sigrid Jusélius Stiftelse.  相似文献   
992.
993.
The objective of this article is to uncover benefits and risks of Integrated Product Service Offering (IPSO) in a systematic manner. To do so, it adopts an explorative longitudinal in-depth case study (development of an IPSO based on a new technology) and adds insights to the existing literature. The article first proposes a theoretical and generic framework termed the PCP (Provider - Customer - Product) triangle with associated information flow and uncertainty. Second, various types of benefits and risks are presented based on the framework. Among others, the benefit of keeping IPR (Intellectual Property Rights) with the provider and the risk of regulation change are new findings from the case study. In addition, the case study reveals that IPSO is regarded as a positive contributor to innovation. Applying the framework and classification of benefits and risks as norms to other cases has yet to be done for verification. However, the framework contributes scientifically to a better understanding of the benefits and risks of IPSO. In addition, this framework is advantageous with its easiness to understand, which contributes practically to the dissemination of IPS0 insight to industry.  相似文献   
994.
This article explores the potential of integrating Participatory Learning and Action Research (PLAR) and Systems Ecology (SE) for improving research capability in facilitating sustainable development transitions in agriculture. Goal conflicts that arose in a PLAR group working on sustainability issues in small-scale organic tomato production are analysed from the perspective of SE. The possibility to improve agency for sustainable development by the merger of PLAR and SE are discussed. It is concluded that the approaches together could provide a sounder base for systemic research and transitions in agriculture.  相似文献   
995.
Graef  F.  Mutabazi  K. D.  Sieber  S.  Asch  F.  Makoko  B.  Bonatti  M.  Brüntrup  M.  Gornott  C.  Herrmann  L.  Herrmann  R.  Kaburire  L.  Kahimba  F. C.  Kimaro  A.  Kuntosch  A.  König  H. J.  Lagwen  P.  Lana  M. A.  Lambert  C.  Levy  C.  Löhr  K.  Maeda  C.  Mbwana  H.  Mchau  D.  Mnimbo  M. T.  Munder  S.  Mwinuka  L.  Ngwenya  P.  Nickson  E.  Nkonya  E.  Saidia  P.  Schäfer  M. P.  Schindler  J.  Silayo  V.  Uckert  G.  Wambura  J.  William  L. 《Systemic Practice and Action Research》2019,32(4):359-378
Systemic Practice and Action Research - Upgrading local food value chains is a promising approach to invigorating African food systems. This endeavour warrants multi-disciplinary North-South...  相似文献   
996.
Congenital disorders of glycosylation (CDG) comprise a rapidly growing group of inherited disorders in which glycosylation of glycoproteins is defective due to mutations in genes required for the assembly of lipid-linked oligosaccharides, their transfer to nascent glycoproteins (CDG-I) or the processing of protein-bound glycans (CDG-II). Previously' a defect in the GDP-fucose import into the lumen of the Golgi was identified in a person with CDG (A.C.) with a general deficiency of fucosyl residues in glycoproteins. This patient presents the clinical features of leukocyte adhesion deficiency type II (LAD II) including mental retardation, short stature, facial stigmata, and recurrent bacterial peripheral infections with persistently elevated peripheral leukocytes. Using a fucose-specific, lectin-staining procedure for detection of fucosylated glycoproteins and a retroviral cDNA library, we isolated a cDNA complementing the fucosylation defect in the patient's fibroblasts. The cDNA encodes a highly hydrophobic protein of 364 amino acids with multiple putative transmembrane domains. Restoration of GDP-fucose import activity in Golgi-enriched vesicles from the patient's fibroblasts verified the GDP-fucose transporter activity of this protein. We identified two missense mutations in the GDP-fucose transporter cDNA of patient A.C. and of two other people with LAD II. Thus complementation cloning allowed us to identify the human GDP-fucose transporter cDNA and GDP-fucose transporter deficiency as a cause for a new type of CDG. Following the recent recommendations for the nomenclature for CDG, this new type is classified as CDG-IIc (formerly LAD II).  相似文献   
997.
Most island-arc magmatism appears to result from the lowering of the melting point of peridotite within the wedge of mantle above subducting slabs owing to the introduction of fluids from the dehydration of subducting oceanic crust. Volcanic rocks interpreted to contain a component of melt (not just a fluid) from the subducting slab itself are uncommon, but possible examples have been recognized in the Aleutian islands, Baja California, Patagonia and elsewhere. The geochemically distinctive rocks from these areas, termed 'adakites, are often associated with subducting plates that are young and warm, and therefore thought to be more prone to melting. But the subducting lithosphere in some adakite locations (such as the Aleutian islands) appears to be too old and hence too cold to melt. This implies either that our interpretation of adakite geochemistry is incorrect, or that our understanding of the tectonic context of adakites is incomplete. Here we present geochemical data from the Kamchatka peninsula and the Aleutian islands that reaffirms the slab-melt interpretation of adakites, but in the tectonic context of the exposure to mantle flow around the edge of a torn subducting plate. We conclude that adakites are likely to form whenever the edge of a subducting plate is warmed or ablated by mantle flow. The use of adakites as tracers for such plate geometry may improve our understanding of magma genesis and thermal structure in a variety of subduction-zone environments.  相似文献   
998.
Richter C  Wunsch M  Rasheed M  Kötter I  Badran MI 《Nature》2001,413(6857):726-730
Framework cavities are the largest but least explored coral reef habitat. Previous dive studies of caverns, spaces below plate corals, rubble and artificial cavities suggest that cavity-dwelling (coelobite) filter-feeders are important in the trophodynamics of reefs. Quantitative community data are lacking, however, as the bulk of the narrow crevices interlacing the reef framework are inaccessible to conventional analysis methods. Here we have developed endoscopic techniques to explore Red Sea framework crevices up to 4 m into the carbonate rock, revealing a large internal surface (2.5-7.4 m2 per projected m2 reef) dominated by encrusting filter-feeders. Sponges alone provided up to 60% of coelobite cover, outweighing epi-reefal filter-feeder biomass by two orders of magnitude. Coelobite community filtration removed more than 60% of the phytoplankton in the course of its less than 5-minute passage through the crevices, corresponding to an uptake of roughly 0.9 g carbon m-2 d-1. Mineralization of the largely allochthonous organic material is a principal source of nutrients supporting coral and algal growth. The supply of new material by coelobites may provide a key to understanding the 'coral reef paradox'-a rich ecosystem thriving in nutrient-poor water.  相似文献   
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1000.
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