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排序方式: 共有192条查询结果,搜索用时 0 毫秒
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Exome sequencing identifies frequent mutation of the SWI/SNF complex gene PBRM1 in renal carcinoma 总被引:1,自引:0,他引:1
Varela I Tarpey P Raine K Huang D Ong CK Stephens P Davies H Jones D Lin ML Teague J Bignell G Butler A Cho J Dalgliesh GL Galappaththige D Greenman C Hardy C Jia M Latimer C Lau KW Marshall J McLaren S Menzies A Mudie L Stebbings L Largaespada DA Wessels LF Richard S Kahnoski RJ Anema J Tuveson DA Perez-Mancera PA Mustonen V Fischer A Adams DJ Rust A Chan-on W Subimerb C Dykema K Furge K Campbell PJ Teh BT Stratton MR Futreal PA 《Nature》2011,469(7331):539-542
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Yokoyama S Woods SL Boyle GM Aoude LG MacGregor S Zismann V Gartside M Cust AE Haq R Harland M Taylor JC Duffy DL Holohan K Dutton-Regester K Palmer JM Bonazzi V Stark MS Symmons J Law MH Schmidt C Lanagan C O'Connor L Holland EA Schmid H Maskiell JA Jetann J Ferguson M Jenkins MA Kefford RF Giles GG Armstrong BK Aitken JF Hopper JL Whiteman DC Pharoah PD Easton DF Dunning AM Newton-Bishop JA Montgomery GW Martin NG Mann GJ Bishop DT Tsao H Trent JM Fisher DE Hayward NK Brown KM 《Nature》2011,480(7375):99-103
96.
Sharply increased mass loss from glaciers and ice caps in the Canadian Arctic Archipelago 总被引:1,自引:0,他引:1
Gardner AS Moholdt G Wouters B Wolken GJ Burgess DO Sharp MJ Cogley JG Braun C Labine C 《Nature》2011,473(7347):357-360
Mountain glaciers and ice caps are contributing significantly to present rates of sea level rise and will continue to do so over the next century and beyond. The Canadian Arctic Archipelago, located off the northwestern shore of Greenland, contains one-third of the global volume of land ice outside the ice sheets, but its contribution to sea-level change remains largely unknown. Here we show that the Canadian Arctic Archipelago has recently lost 61?±?7?gigatonnes per year (Gt?yr(-1)) of ice, contributing 0.17?±?0.02 mm?yr(-1) to sea-level rise. Our estimates are of regional mass changes for the ice caps and glaciers of the Canadian Arctic Archipelago referring to the years 2004 to 2009 and are based on three independent approaches: surface mass-budget modelling plus an estimate of ice discharge (SMB+D), repeat satellite laser altimetry (ICESat) and repeat satellite gravimetry (GRACE). All three approaches show consistent and large mass-loss estimates. Between the periods 2004-2006 and 2007-2009, the rate of mass loss sharply increased from 31?±?8?Gt?yr(-1) to 92?±?12?Gt?yr(-1) in direct response to warmer summer temperatures, to which rates of ice loss are highly sensitive (64?±?14?Gt?yr(-1) per 1?K increase). The duration of the study is too short to establish a long-term trend, but for 2007-2009, the increase in the rate of mass loss makes the Canadian Arctic Archipelago the single largest contributor to eustatic sea-level rise outside Greenland and Antarctica. 相似文献
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Bodin K Ellmerich S Kahan MC Tennent GA Loesch A Gilbertson JA Hutchinson WL Mangione PP Gallimore JR Millar DJ Minogue S Dhillon AP Taylor GW Bradwell AR Petrie A Gillmore JD Bellotti V Botto M Hawkins PN Pepys MB 《Nature》2010,468(7320):93-97
Accumulation of amyloid fibrils in the viscera and connective tissues causes systemic amyloidosis, which is responsible for about one in a thousand deaths in developed countries. Localized amyloid can also have serious consequences; for example, cerebral amyloid angiopathy is an important cause of haemorrhagic stroke. The clinical presentations of amyloidosis are extremely diverse and the diagnosis is rarely made before significant organ damage is present. There is therefore a major unmet need for therapy that safely promotes the clearance of established amyloid deposits. Over 20 different amyloid fibril proteins are responsible for different forms of clinically significant amyloidosis and treatments that substantially reduce the abundance of the respective amyloid fibril precursor proteins can arrest amyloid accumulation. Unfortunately, control of fibril-protein production is not possible in some forms of amyloidosis and in others it is often slow and hazardous. There is no therapy that directly targets amyloid deposits for enhanced clearance. However, all amyloid deposits contain the normal, non-fibrillar plasma glycoprotein, serum amyloid P component (SAP). Here we show that administration of anti-human-SAP antibodies to mice with amyloid deposits containing human SAP triggers a potent, complement-dependent, macrophage-derived giant cell reaction that swiftly removes massive visceral amyloid deposits without adverse effects. Anti-SAP-antibody treatment is clinically feasible because circulating human SAP can be depleted in patients by the bis-d-proline compound CPHPC, thereby enabling injected anti-SAP antibodies to reach residual SAP in the amyloid deposits. The unprecedented capacity of this novel combined therapy to eliminate amyloid deposits should be applicable to all forms of systemic and local amyloidosis. 相似文献
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Cryptic striations in the upper mantle revealed by hafnium isotopes in southeast Indian ridge basalts 总被引:1,自引:0,他引:1
The Earth's mantle is isotopically heterogeneous on length scales ranging from centimetres to more than 10(4) kilometres. This heterogeneity originates from partial melt extraction and plate tectonic recycling, whereas stirring during mantle convection tends to reduce it. Here we show that mid-ocean ridge basalts from 2,000 km along the southeast Indian ridge (SEIR) display a bimodal hafnium isotopic distribution. This bimodality reveals the presence of ancient compositional striations (streaks) in the Indian Ocean upper mantle. The number density of the streaks is described by a Poisson distribution, with an average thickness of approximately 40 km. Such a distribution is anticipated for a well-stirred upper mantle, in which heterogeneity is continually introduced by plate tectonic recycling, and redistributed by viscous stretching and convective refolding. 相似文献
100.
The supply of some essential metals to pelagic ecosystems is less than the demand, so many phytoplankton have slow rates of photosynthetic production and restricted growth. The types and amounts of metals required by phytoplankton depends on their evolutionary history and on their adaptations to metal availability, which varies widely among ocean habitats. Diatoms, for example, need considerably less iron (Fe) to grow than chlorophyll-b-containing taxa, and the oceanic species demand roughly one-tenth the amount of coastal strains. Like Fe, copper (Cu) is scarce in the open sea, but notably higher concentrations of it are required for the growth of oceanic than of coastal isolates. Here we report that the greater Cu requirement in an oceanic diatom, Thalassiosira oceanica, is entirely due to a single Cu-containing protein, plastocyanin, which--until now--was only known to exist in organisms with chlorophyll b and cyanobacteria. Algae containing chlorophyll c, including the closely related coastal species T. weissflogii, are thought to lack plastocyanin and contain a functionally equivalent Fe-containing homologue, cytochrome c6 (ref. 9). Copper deficiency in T. oceanica inhibits electron transport regardless of Fe status, implying a constitutive role for plastocyanin in the light reactions of photosynthesis in this species. The results suggest that selection pressure imposed by Fe limitation has resulted in the use of a Cu protein for photosynthesis in an oceanic diatom. This biochemical switch reduces the need for Fe and increases the requirement for Cu, which is relatively more abundant in the open sea. 相似文献