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71.
Humphray SJ Oliver K Hunt AR Plumb RW Loveland JE Howe KL Andrews TD Searle S Hunt SE Scott CE Jones MC Ainscough R Almeida JP Ambrose KD Ashwell RI Babbage AK Babbage S Bagguley CL Bailey J Banerjee R Barker DJ Barlow KF Bates K Beasley H Beasley O Bird CP Bray-Allen S Brown AJ Brown JY Burford D Burrill W Burton J Carder C Carter NP Chapman JC Chen Y Clarke G Clark SY Clee CM Clegg S Collier RE Corby N Crosier M Cummings AT Davies J Dhami P Dunn M Dutta I Dyer LW Earthrowl ME Faulkner L 《Nature》2004,429(6990):369-374
Chromosome 9 is highly structurally polymorphic. It contains the largest autosomal block of heterochromatin, which is heteromorphic in 6-8% of humans, whereas pericentric inversions occur in more than 1% of the population. The finished euchromatic sequence of chromosome 9 comprises 109,044,351 base pairs and represents >99.6% of the region. Analysis of the sequence reveals many intra- and interchromosomal duplications, including segmental duplications adjacent to both the centromere and the large heterochromatic block. We have annotated 1,149 genes, including genes implicated in male-to-female sex reversal, cancer and neurodegenerative disease, and 426 pseudogenes. The chromosome contains the largest interferon gene cluster in the human genome. There is also a region of exceptionally high gene and G + C content including genes paralogous to those in the major histocompatibility complex. We have also detected recently duplicated genes that exhibit different rates of sequence divergence, presumably reflecting natural selection. 相似文献
72.
Naish TR Woolfe KJ Barrett PJ Wilson GS Atkins C Bohaty SM Bücker CJ Claps M Davey FJ Dunbar GB Dunn AG Fielding CR Florindo F Hannah MJ Harwood DM Henrys SA Krissek LA Lavelle M van Der Meer J McIntosh WC Niessen F Passchier S Powell RD Roberts AP Sagnotti L Scherer RP Strong CP Talarico F Verosub KL Villa G Watkins DK Webb PN Wonik T 《Nature》2001,413(6857):719-723
Between 34 and 15 million years (Myr) ago, when planetary temperatures were 3-4 degrees C warmer than at present and atmospheric CO2 concentrations were twice as high as today, the Antarctic ice sheets may have been unstable. Oxygen isotope records from deep-sea sediment cores suggest that during this time fluctuations in global temperatures and high-latitude continental ice volumes were influenced by orbital cycles. But it has hitherto not been possible to calibrate the inferred changes in ice volume with direct evidence for oscillations of the Antarctic ice sheets. Here we present sediment data from shallow marine cores in the western Ross Sea that exhibit well dated cyclic variations, and which link the extent of the East Antarctic ice sheet directly to orbital cycles during the Oligocene/Miocene transition (24.1-23.7 Myr ago). Three rapidly deposited glacimarine sequences are constrained to a period of less than 450 kyr by our age model, suggesting that orbital influences at the frequencies of obliquity (40 kyr) and eccentricity (125 kyr) controlled the oscillations of the ice margin at that time. An erosional hiatus covering 250 kyr provides direct evidence for a major episode of global cooling and ice-sheet expansion about 23.7 Myr ago, which had previously been inferred from oxygen isotope data (Mi1 event). 相似文献
73.
74.
Zusammenfassung Feststellung eines Tag-Nacht-Rhythmus der Konzentration von Adrenalin und Noradrenalin in den Nebennieren von Ratten.
Supported by U.S.P.H.S. Grant No. NS-08929.
Acknowledgements. We would like to express our appreciation toLaurel Patterson andJacqueline Skaggs for their excellent technical and secretarial assistance. 相似文献
Supported by U.S.P.H.S. Grant No. NS-08929.
Acknowledgements. We would like to express our appreciation toLaurel Patterson andJacqueline Skaggs for their excellent technical and secretarial assistance. 相似文献
75.
76.
The dynamics of chromosome evolution in birds and mammals 总被引:20,自引:0,他引:20
Burt DW Bruley C Dunn IC Jones CT Ramage A Law AS Morrice DR Paton IR Smith J Windsor D Sazanov A Fries R Waddington D 《Nature》1999,402(6760):411-413
Comparative mapping, which compares the location of homologous genes in different species, is a powerful tool for studying genome evolution. Comparative maps suggest that rates of chromosomal change in mammals can vary from one to ten rearrangements per million years. On the basis of these rates we would expect 84 to 600 conserved segments in a chicken comparison with human or mouse. Here we build comparative maps between these species and estimate that numbers of conserved segments are in the lower part of this range. We conclude that the organization of the human genome is closer to that of the chicken than the mouse and by adding comparative mapping results from a range of vertebrates, we identify three possible phases of chromosome evolution. The relative stability of genomes such as those of the chicken and human will enable the reconstruction of maps of ancestral vertebrates. 相似文献
77.
A complete BAC-based physical map of the Arabidopsis thaliana genome. 总被引:11,自引:0,他引:11
T Mozo K Dewar P Dunn J R Ecker S Fischer S Kloska H Lehrach M Marra R Martienssen S Meier-Ewert T Altmann 《Nature genetics》1999,22(3):271-275
Arabidopsis thaliana is a small flowering plant that serves as the major model system in plant molecular genetics. The efforts of many scientists have produced genetic maps that provide extensive coverage of the genome (http://genome-www. stanford.edu/Arabidopsis/maps.html). Recently, detailed YAC, BAC, P1 and cosmid-based physical maps (that is, representations of genomic regions as sets of overlapping clones of corresponding libraries) have been established that extend over wide genomic areas ranging from several hundreds of kilobases to entire chromosomes. These maps provide an entry to gain deeper insight into the A. thaliana genome structure. A. thaliana has been chosen as the subject of the first large-scale project intended to determine the full genome sequence of a plant. This sequencing project, together with the increasing interest in map-based gene cloning, has highlighted the requirement for a complete and accurate physical map of this plant species. To supply the scientific community with a high-quality resource, we present here a complete physical map of A. thaliana using essentially the IGF BAC library. The map consists of 27 contigs that cover the entire genome, except for the presumptive centromeric regions, nucleolar organization regions (NOR) and telomeric areas. This is the first reported map of a complex organism based entirely on BAC clones and it represents the most homogeneous and complete physical map established to date for any plant genome. Furthermore, the analysis performed here serves as a model for an efficient physical mapping procedure using BAC clones that can be applied to other complex genomes. 相似文献