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NATURE文献大全abstract::Alphabeta T lymphocytes are able to detect even a single peptide-major histocompatibility complex (MHC) on the surface of an antigen-presenting cell. This is despite clear evidence, at least with CD4+ T cells, that monomeric ligands are not stimulatory. In an effort to understand how this remarkable sensitivity is ach...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature03391
更新日期:2005-03-10 00:00:00
abstract::Levels of gene expression underpin organismal phenotypes1,2, but the nature of selection that acts on gene expression and its role in adaptive evolution remain unknown1,2. Here we assayed gene expression in rice (Oryza sativa)3, and used phenotypic selection analysis to estimate the type and strength of selection on t...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/s41586-020-1997-2
更新日期:2020-02-01 00:00:00
abstract::At early stages of the mammalian visual cortex, neurons with similar stimulus selectivities are vertically arrayed through the thickness of the cortical sheet and clustered in patches or bands across the surface. This organization, referred to as a 'column', has been found with respect to one-dimensional stimulus para...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/360343a0
更新日期:1992-11-26 00:00:00
abstract::Protein aggregates are the hallmark of stressed and ageing cells, and characterize several pathophysiological states. Healthy metazoan cells effectively eliminate intracellular protein aggregates, indicating that efficient disaggregation and/or degradation mechanisms exist. However, metazoans lack the key heat-shock p...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature14884
更新日期:2015-08-13 00:00:00
abstract::Some observations suggest that very massive stars experience extreme mass-loss episodes shortly before they explode as supernovae, as do several models. Establishing a causal connection between these mass-loss episodes and the final explosion would provide a novel way to study pre-supernova massive-star evolution. Her...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature11877
更新日期:2013-02-07 00:00:00
abstract::Clonal deletion in the thymus plays a major part in T-cell tolerance to self antigens. But the mechanism of negative selection, its fine specificity and the threshold of affinity and avidity remains unknown. We have now examined these aspects of negative selection with mice expressing a transgenic T-cell receptor with...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/351482a0
更新日期:1991-06-06 00:00:00
abstract::The class II region of the human major histocompatibility complex (MHC) encodes a polymorphic set of cell surface glycoproteins involved in the regulation of the immune response. Each glycoprotein is a heterodimer composed of a alpha-chain of relative molecular mass (Mr) 34,000 (34 K) and a beta-chain of Mr = 28K. The...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/323453a0
更新日期:1986-10-02 00:00:00
abstract::Recognition of objects or environmental landmarks is problematic because appearance can vary widely depending on illumination, viewing distance, angle of view and so on. Storing a separate image or 'template' for every possible view requires vast numbers to be stored and scanned, has a high probability of recognition ...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/35001064
更新日期:2000-02-10 00:00:00
abstract::The spectral purity of an oscillator is central to many applications, such as detecting gravity waves, defining the second, ground-state cooling and quantum manipulation of nanomechanical objects, and quantum computation. Recent proposals suggest that laser oscillators which use very narrow optical transitions in atom...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature10920
更新日期:2012-04-04 00:00:00
abstract::Globular star clusters that formed at the same cosmic time may have evolved rather differently from the dynamical point of view (because that evolution depends on the internal environment) through a variety of processes that tend progressively to segregate stars more massive than the average towards the cluster centre...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature11686
更新日期:2012-12-20 00:00:00
abstract::It is common knowledge that our feelings of alertness or drowsiness vary throughout the day. Indeed, this diurnal variation is so widely accepted that it has been used to validate the drowsy/alert component of activation obtained from mood adjective checklists. There is, however, some evidence from sleep deprivation a...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/313678a0
更新日期:1985-02-21 00:00:00
abstract::Retinal nerve fibres form an orderly map of visual space in several centres in the vertebrate brain. Such topographic maps are a common feature of central nervous system organization, yet the way in which they develop is poorly understood. Early nerve projections in the fetal and neonatal mammalian brain have been fou...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/301150a0
更新日期:1983-01-13 00:00:00
abstract::Retinoic-acid-inducible gene-I (RIG-I; also called DDX58) is a cytosolic viral RNA receptor that interacts with MAVS (also called VISA, IPS-1 or Cardif) to induce type I interferon-mediated host protective innate immunity against viral infection. Furthermore, members of the tripartite motif (TRIM) protein family, whic...
journal_title:Nature
pub_type: 信件
doi:10.1038/nature05732
更新日期:2007-04-19 00:00:00
abstract::Simple mathematical models of the transmission dynamics of HIV that incorporate demographic and epidemiological processes to assess the potential impact of AIDS on human population growth and structure in developing countries suggest that AIDS is capable of changing population growth rates from positive to negative va...
journal_title:Nature
pub_type: 杂志文章,评审
doi:10.1038/332228a0
更新日期:1988-03-17 00:00:00
abstract::Contamination of ground waters with water-soluble aromatic hydrocarbons, common components of petroleum pollution, often produces anoxic conditions under which microbial degradation of the aromatics is slow. Oxygen is often added to contaminated ground water to stimulate biodegradation, but this can be technically dif...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/370128a0
更新日期:1994-07-14 00:00:00
abstract::(Na+ + K+)ATPase contains two different subunits, a catalytic subunit (alpha) and a subunit with uncertain function (beta). The enzyme binds ATP, ouabain and vanadate, and can be phosphorylated by ATP as well as by inorganic phosphate. From the previously reported maximal binding and phosphorylation capacities of 3.5-...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/290338a0
更新日期:1981-03-26 00:00:00
abstract::Several systems, including contractile tail bacteriophages, the type VI secretion system and R-type pyocins, use a multiprotein tubular apparatus to attach to and penetrate host cell membranes. This macromolecular machine resembles a stretched, coiled spring (or sheath) wound around a rigid tube with a spike-shaped pr...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature17971
更新日期:2016-05-19 00:00:00
abstract::The gut microbiota influences development1-3 and homeostasis4-7 of the mammalian immune system, and is associated with human inflammatory8 and immune diseases9,10 as well as responses to immunotherapy11-14. Nevertheless, our understanding of how gut bacteria modulate the immune system remains limited, particularly in ...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/s41586-020-2971-8
更新日期:2020-12-01 00:00:00
abstract::Most tetrapods have retained terrestrial locomotion since it evolved in the Palaeozoic era, but bats have become so specialized for flight that they have almost lost the ability to manoeuvre on land at all. Vampire bats, which sneak up on their prey along the ground, are an important exception. Here we show that commo...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/434292a
更新日期:2005-03-17 00:00:00
abstract::The foundations of mammalian development lie in a cluster of embryonic epiblast stem cells. In response to extracellular matrix signalling, these cells undergo epithelialization and create an apical surface in contact with a cavity, a fundamental event for all subsequent development. Concomitantly, epiblast cells tran...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature24675
更新日期:2017-12-14 00:00:00
abstract::Mutations in the Schizosaccharomyces pombe cdc8 gene impair cytokinesis. Here we clone cdc8+ and find that it encodes a novel tropomyosin. Gene disruption results in lethal arrest of the cell cycle, but spore germination, cell growth, DNA replication and mitosis are all unaffected. Haploid cdc8 gene disruptants are re...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/360084a0
更新日期:1992-11-05 00:00:00
abstract::Ice sheets are currently ignored in global methane budgets1,2. Although ice sheets have been proposed to contain large reserves of methane that may contribute to a rise in atmospheric methane concentration if released during periods of rapid ice retreat3,4, no data exist on the current methane footprint of ice sheets....
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/s41586-018-0800-0
更新日期:2019-01-01 00:00:00
abstract::Numerous reports have emphasized the need for major changes in the global food system: agriculture must meet the twin challenge of feeding a growing population, with rising demand for meat and high-calorie diets, while simultaneously minimizing its global environmental impacts. Organic farming—a system aimed at produc...
journal_title:Nature
pub_type: 杂志文章,meta分析
doi:10.1038/nature11069
更新日期:2012-05-10 00:00:00
abstract::The direct involvement of the pituitary-adrenal axis in birth has been well established, at least in sheep, and its removal prolongs pregnancy. As part of the process the fetal sheep adrenal grows rapidly during the 10-15 d prepartum and is associated with a large rise in the plasma corticosteroid concentration. This ...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/284616a0
更新日期:1980-04-17 00:00:00
abstract::Four incorrect figure citations in this Letter have been corrected online. ...
journal_title:Nature
pub_type: 杂志文章,已发布勘误
doi:10.1038/s41586-018-0560-x
更新日期:2018-11-01 00:00:00
abstract::The identification of novel metabolites and the characterization of their biological functions are major challenges in biology. X-ray crystallography can reveal unanticipated ligands that persist through purification and crystallization. These adventitious protein-ligand complexes provide insights into new activities,...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature12180
更新日期:2013-06-06 00:00:00
abstract::B-RAF is the most frequently mutated protein kinase in human cancers. The finding that oncogenic mutations in BRAF are common in melanoma, followed by the demonstration that these tumours are dependent on the RAF/MEK/ERK pathway, offered hope that inhibition of B-RAF kinase activity could benefit melanoma patients. He...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature09454
更新日期:2010-09-30 00:00:00
abstract::The initiation of immunoglobulin-E (IgE)-mediated allergic responses requires the binding of IgE antibody to its high-affinity receptor, Fc epsilonRI. Crosslinking of Fc epsilonRI initiates an intracellular signal transduction cascade that triggers the release of mediators of the allergic response. The interaction of ...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/35018500
更新日期:2000-07-20 00:00:00
abstract::The development of colloidal quantum dots has led to practical applications of quantum confinement, such as in solution-processed solar cells, lasers and as biological labels. Further scientific and technological advances should be achievable if these colloidal quantum systems could be electronically coupled in a gene...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature02695
更新日期:2004-07-08 00:00:00
abstract::Macroscopic mechanical objects and electromagnetic degrees of freedom can couple to each other through radiation pressure. Optomechanical systems in which this coupling is sufficiently strong are predicted to show quantum effects and are a topic of considerable interest. Devices in this regime would offer new types of...
journal_title:Nature
pub_type: 杂志文章
doi:10.1038/nature06715
更新日期:2008-03-06 00:00:00