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911.
Trace element signature of subduction-zone fluids, melts and supercritical liquids at 120-180 km depth 总被引:14,自引:0,他引:14
Fluids and melts liberated from subducting oceanic crust recycle lithophile elements back into the mantle wedge, facilitate melting and ultimately lead to prolific subduction-zone arc volcanism. The nature and composition of the mobile phases generated in the subducting slab at high pressures have, however, remained largely unknown. Here we report direct LA-ICPMS measurements of the composition of fluids and melts equilibrated with a basaltic eclogite at pressures equivalent to depths in the Earth of 120-180 km and temperatures of 700-1,200 degrees C. The resultant liquid/mineral partition coefficients constrain the recycling rates of key elements. The dichotomy of dehydration versus melting at 120 km depth is expressed through contrasting behaviour of many trace elements (U/Th, Sr, Ba, Be and the light rare-earth elements). At pressures equivalent to 180 km depth, however, a supercritical liquid with melt-like solubilities for the investigated trace elements is observed, even at low temperatures. This mobilizes most of the key trace elements (except the heavy rare-earth elements, Y and Sc) and thus limits fluid-phase transfer of geochemical signatures in subduction zones to pressures less than 6 GPa. 相似文献
912.
913.
An expression profile for diagnosis of lymph node metastases from primary head and neck squamous cell carcinomas 总被引:15,自引:0,他引:15
Roepman P Wessels LF Kettelarij N Kemmeren P Miles AJ Lijnzaad P Tilanus MG Koole R Hordijk GJ van der Vliet PC Reinders MJ Slootweg PJ Holstege FC 《Nature genetics》2005,37(2):182-186
Metastasis is the process by which cancers spread to distinct sites in the body. It is the principal cause of death in individuals suffering from cancer. For some types of cancer, early detection of metastasis at lymph nodes close to the site of the primary tumor is pivotal for appropriate treatment. Because it can be difficult to detect lymph node metastases reliably, many individuals currently receive inappropriate treatment. We show here that DNA microarray gene-expression profiling can detect lymph node metastases for primary head and neck squamous cell carcinomas that arise in the oral cavity and oropharynx. The predictor, established with an 82-tumor training set, outperforms current clinical diagnosis when independently validated. The 102 predictor genes offer unique insights into the processes underlying metastasis. The results show that the metastatic state can be deciphered from the primary tumor gene-expression pattern and that treatment can be substantially improved. 相似文献
914.
Mutations in the pleckstrin homology domain of dynamin 2 cause dominant intermediate Charcot-Marie-Tooth disease 总被引:5,自引:0,他引:5
Züchner S Noureddine M Kennerson M Verhoeven K Claeys K De Jonghe P Merory J Oliveira SA Speer MC Stenger JE Walizada G Zhu D Pericak-Vance MA Nicholson G Timmerman V Vance JM 《Nature genetics》2005,37(3):289-294
Charcot-Marie-Tooth (CMT) disease is a clinically and genetically heterogeneous group of peripheral neuropathies. Different chromosomal loci have been linked with three autosomal dominant, 'intermediate' types of CMT: DI-CMTA, DI-CMTB and DI-CMTC. We refined the locus associated with DI-CMTB on chromosome 19p12-13.2 to 4.2 Mb in three unrelated families with CMT originating from Australia, Belgium and North America. After screening candidate genes, we identified unique mutations in dynamin 2 (DNM2) in all families. DNM2 belongs to the family of large GTPases and is part of the cellular fusion-fission apparatus. In transiently transfected cell lines, mutations of DNM2 substantially diminish binding of DNM2 to membranes by altering the conformation of the beta3/beta4 loop of the pleckstrin homology domain. Additionally, in the Australian and Belgian pedigrees, which carry two different mutations affecting the same amino acid, Lys558, CMT cosegregated with neutropenia, which has not previously been associated with CMT neuropathies. 相似文献
915.
916.
Mutations in SEPT9 cause hereditary neuralgic amyotrophy 总被引:7,自引:0,他引:7
Kuhlenbäumer G Hannibal MC Nelis E Schirmacher A Verpoorten N Meuleman J Watts GD De Vriendt E Young P Stögbauer F Halfter H Irobi J Goossens D Del-Favero J Betz BG Hor H Kurlemann G Bird TD Airaksinen E Mononen T Serradell AP Prats JM Van Broeckhoven C De Jonghe P Timmerman V Ringelstein EB Chance PF 《Nature genetics》2005,37(10):1044-1046
Hereditary neuralgic amyotrophy (HNA) is an autosomal dominant recurrent neuropathy affecting the brachial plexus. HNA is triggered by environmental factors such as infection or parturition. We report three mutations in the gene septin 9 (SEPT9) in six families with HNA linked to chromosome 17q25. HNA is the first monogenetic disease caused by mutations in a gene of the septin family. Septins are implicated in formation of the cytoskeleton, cell division and tumorigenesis. 相似文献
917.
Mutations in the endosomal ESCRTIII-complex subunit CHMP2B in frontotemporal dementia 总被引:21,自引:0,他引:21
Skibinski G Parkinson NJ Brown JM Chakrabarti L Lloyd SL Hummerich H Nielsen JE Hodges JR Spillantini MG Thusgaard T Brandner S Brun A Rossor MN Gade A Johannsen P Sørensen SA Gydesen S Fisher EM Collinge J 《Nature genetics》2005,37(8):806-808
We have previously reported a large Danish pedigree with autosomal dominant frontotemporal dementia (FTD) linked to chromosome 3 (FTD3). Here we identify a mutation in CHMP2B, encoding a component of the endosomal ESCRTIII complex, and show that it results in aberrant mRNA splicing in tissue samples from affected members of this family. We also describe an additional missense mutation in an unrelated individual with FTD. Aberration in the endosomal ESCRTIII complex may result in FTD and neurodegenerative disease. 相似文献
918.
Extent, duration and speed of the 2004 Sumatra-Andaman earthquake imaged by the Hi-Net array 总被引:1,自引:0,他引:1
The disastrous Sumatra-Andaman earthquake of 26 December 2004 was one of the largest ever recorded. The damage potential of such earthquakes depends on the extent and magnitude of fault slip. The first reliable moment magnitude estimate of 9.0 was obtained several hours after the Sumatra-Andaman earthquake, but more recent, longer-period, normal-mode analyses have indicated that it had a moment magnitude of 9.3, about 2.5 times larger. Here we introduce a method for directly imaging earthquake rupture that uses the first-arriving compressional wave and is potentially able to produce detailed images within 30 min of rupture initiation. We used the Hi-Net seismic array in Japan as an antenna to map the progression of slip by monitoring the direction of high-frequency radiation. We find that the rupture spread over the entire 1,300-km-long aftershock zone by propagating northward at roughly 2.8 km s(-1) for approximately 8 minutes. Comparisons with the aftershock areas of other great earthquakes indicate that the Sumatra-Andaman earthquake did indeed have a moment magnitude of approximately 9.3. Its rupture, in both duration and extent, is the longest ever recorded. 相似文献
919.
920.
Wildermuth S Hofferberth S Lesanovsky I Haller E Andersson LM Groth S Bar-Joseph I Krüger P Schmiedmayer J 《Nature》2005,435(7041):440
Today's magnetic-field sensors are not capable of making measurements with both high spatial resolution and good field sensitivity. For example, magnetic force microscopy allows the investigation of magnetic structures with a spatial resolution in the nanometre range, but with low sensitivity, whereas SQUIDs and atomic magnetometers enable extremely sensitive magnetic-field measurements to be made, but at low resolution. Here we use one-dimensional Bose-Einstein condensates in a microscopic field-imaging technique that combines high spatial resolution (within 3 micrometres) with high field sensitivity (300 picotesla). 相似文献