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51.
52.
Whole-genome sequence of Schistosoma haematobium 总被引:1,自引:0,他引:1
Young ND Jex AR Li B Liu S Yang L Xiong Z Li Y Cantacessi C Hall RS Xu X Chen F Wu X Zerlotini A Oliveira G Hofmann A Zhang G Fang X Kang Y Campbell BE Loukas A Ranganathan S Rollinson D Rinaldi G Brindley PJ Yang H Wang J Wang J Gasser RB 《Nature genetics》2012,44(2):221-225
Schistosomiasis is a neglected tropical disease caused by blood flukes (genus Schistosoma; schistosomes) and affecting 200 million people worldwide. No vaccines are available, and treatment relies on one drug, praziquantel. Schistosoma haematobium has come into the spotlight as a major cause of urogenital disease, as an agent linked to bladder cancer and as a predisposing factor for HIV/AIDS. The parasite is transmitted to humans from freshwater snails. Worms dwell in blood vessels and release eggs that become embedded in the bladder wall to elicit chronic immune-mediated disease and induce squamous cell carcinoma. Here we sequenced the 385-Mb genome of S. haematobium using Illumina-based technology at 74-fold coverage and compared it to sequences from related parasites. We included genome annotation based on function, gene ontology, networking and pathway mapping. This genome now provides an unprecedented resource for many fundamental research areas and shows great promise for the design of new disease interventions. 相似文献
53.
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} A nesting population of Ferruginous Hawks ( Buteo regalis ) at the eastern edge of the Great Basin in west - central Utah was studied for three nesting seasons, 1972 – 1974, during which time a significant decline in jackrabbit numbers occurred. The total number of hawks and nesting pairs varied throughout the study. In 1972, 16 pairs occupied territories and only 1 pair failed to nest. By 1974, however, only 5 pairs and 2 single birds occupied territories. The number of young fledged ranged from 31 in 1972 to 3 in 1974. The nesting phenology of the Ferruginous Hawk and the reproductive period of black - tailed jackrabbits are clearly correlated. Of the jackrabbit remains collected from hawk nests, 90 percent were from rabbits younger than 13 weeks. The decline in hawk numbers is thought to be directly correlated with a drop in the jackrabbit population. 相似文献
54.
Meiotic crossing-over is highly regulated such that each homolog pair typically receives at least one crossover (assurance) and adjacent crossovers are widely spaced (interference). Here we provide evidence that interference and assurance are mechanistically distinct processes that are separated by mutations in a new ZMM (Zip, Msh, Mer) protein from Saccharomyces cerevisiae, Spo16. Like other zmm mutants, spo16 cells have defects in both crossing-over and synaptonemal complex formation. Unlike in previously characterized zmm mutants, the residual crossovers in spo16 cells show interference comparable to that in the wild type. Spo16 interacts with a second ZMM protein, Spo22 (also known as Zip4), and spo22 mutants also show normal interference. Notably, assembly of the MutS homologs Msh4 and Msh5 on chromosomes occurs in both spo16 and spo22, but not in other zmm mutants. We suggest that crossover interference requires the normal assembly of recombination complexes containing Msh4 and Msh5 but does not require Spo16- and Spo22-dependent extension of synaptonemal complexes. In contrast, crossover assurance requires all ZMM proteins and full-length synaptonemal complexes. 相似文献
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Chendrimada TP Gregory RI Kumaraswamy E Norman J Cooch N Nishikura K Shiekhattar R 《Nature》2005,436(7051):740-744
57.
Auditory imagery occurs when one mentally rehearses telephone numbers or has a song 'on the brain'--it is the subjective experience of hearing in the absence of auditory stimulation, and is useful for investigating aspects of human cognition. Here we use functional magnetic resonance imaging to identify and characterize the neural substrates that support unprompted auditory imagery and find that auditory and visual imagery seem to obey similar basic neural principles. 相似文献
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59.
Significant decadal-scale impact of volcanic eruptions on sea level and ocean heat content 总被引:2,自引:0,他引:2
Ocean thermal expansion contributes significantly to sea-level variability and rise. However, observed decadal variability in ocean heat content and sea level has not been reproduced well in climate models. Aerosols injected into the stratosphere during volcanic eruptions scatter incoming solar radiation, and cause a rapid cooling of the atmosphere and a reduction in rainfall, as well as other changes in the climate system. Here we use observations of ocean heat content and a set of climate simulations to show that large volcanic eruptions result in rapid reductions in ocean heat content and global mean sea level. For the Mt Pinatubo eruption, we estimate a reduction in ocean heat content of about 3 x 10(22) J and a global sea-level fall of about 5 mm. Over the three years following such an eruption, we estimate a decrease in evaporation of up to 0.1 mm d(-1), comparable to observed changes in mean land precipitation. The recovery of sea level following the Mt Pinatubo eruption in 1991 explains about half of the difference between the long-term rate of sea-level rise of 1.8 mm yr(-1) (for 1950-2000), and the higher rate estimated for the more recent period where satellite altimeter data are available (1993-2000). 相似文献
60.
Zhu X Luke A Cooper RS Quertermous T Hanis C Mosley T Gu CC Tang H Rao DC Risch N Weder A 《Nature genetics》2005,37(2):177-181
Identification of genetic variants that contribute to risk of hypertension is challenging. As a complement to linkage and candidate gene association studies, we carried out admixture mapping using genome-scan microsatellite markers among the African American participants in the US National Heart, Lung, and Blood Institute's Family Blood Pressure Program. This population was assumed to have experienced recent admixture from ancestral groups originating in Africa and Europe. We used a set of unrelated individuals from Nigeria to represent the African ancestral population and used the European Americans in the Family Blood Pressure Program to provide estimates of allele frequencies for the European ancestors. We genotyped a common set of 269 microsatellite markers in the three groups at the same laboratory. The distribution of marker location-specific African ancestry, based on multipoint analysis, was shifted upward in hypertensive cases versus normotensive controls, consistent with linkage to genes conferring susceptibility. This shift was largely due to a small number of loci, including five adjacent markers on chromosome 6q and two on chromosome 21q. These results suggest that chromosome 6q24 and 21q21 may contain genes influencing risk of hypertension in African Americans. 相似文献