The GTP-binding protein Ran/TC4 is required for protein import into the nucleus.

abstract：:The observation that a few species in ecological communities are exceptionally abundant, whereas most are rare, prompted the development of species abundance models. Nevertheless, despite the large literature on the commonness and rarity of species inspired by these pioneering studies, some widespread empirical patter...

journal_title：Nature

authors： Magurran AE,Henderson PA

更新日期：2003-04-17 00:00:00

abstract：:T cells bearing the alpha beta receptor can specifically react with target cells coated with staphylococcal enterotoxin and expressing major histocompatibility complex class II molecules; these responses depend on which variable region (V) of the receptor's beta-subunit is used. We have now examined whether a similar ...

journal_title：Nature

authors： Rust CJ,Verreck F,Vietor H,Koning F

更新日期：1990-08-09 00:00:00

abstract：:The chemical composition of basaltic magma erupted at the Earth's surface is the end product of a complex series of processes, beginning with partial melting and melt extraction from a mantle source and ending with fractional crystallization and crustal assimilation at lower pressures. It has been proposed that studyi...

journal_title：Nature

authors： Spandler C,O'Neill HS,Kamenetsky VS

更新日期：2007-05-17 00:00:00

abstract：:The complement system is a key part of the innate immune system, and is required for clearance of pathogens from the bloodstream. After exposure to pathogens, the third component of the complement system, C3, is cleaved to C3b which, after recruitment of factor B, initiates formation of the alternative pathway convert...

journal_title：Nature

authors： Wiesmann C,Katschke KJ,Yin J,Helmy KY,Steffek M,Fairbrother WJ,McCallum SA,Embuscado L,DeForge L,Hass PE,van Lookeren Campagne M

更新日期：2006-11-09 00:00:00

abstract：:Piezoelectric materials, which convert mechanical to electrical energy (and vice versa), are crucial in medical imaging, telecommunication and ultrasonic devices. A new generation of single-crystal materials, such as Pb(Zn1/3Nb2/3)O3-PbTiO3 (PZN-PT) and Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT), exhibit a piezoelectric effect ...

journal_title：Nature

authors： Fu H,Cohen RE

更新日期：2000-01-20 00:00:00

abstract：: ...

journal_title：Nature

authors： Witze A

更新日期：2019-01-01 00:00:00

abstract：:Elongation factor Tu is present in a fourfold excess over the amount seemingly involved in protein synthesis. It is identical to a major protein which we have found associated with the plasma membrane. The possibility of a specific role in that location is considered. ...

journal_title：Nature

authors： Jacobson GR,Rosenbusch JP

更新日期：1976-05-06 00:00:00

abstract：:RNAs that contain specific high-affinity binding sites for small molecule ligands immobilized on a solid support are present at a frequency of roughly one in 10(10)-10(11) in pools of random sequence RNA molecules. Here we describe a new in vitro selection procedure designed to ensure the isolation of RNAs that bind t...

journal_title：Nature

authors： Sassanfar M,Szostak JW

更新日期：1993-08-05 00:00:00

abstract：:Sensory experiences exert a powerful influence on the function and future performance of neuronal circuits in the mammalian neocortex. Restructuring of synaptic connections is believed to be one mechanism by which cortical circuits store information about the sensory world. Excitatory synaptic structures, such as dend...

journal_title：Nature

authors： Hofer SB,Mrsic-Flogel TD,Bonhoeffer T,Hübener M

更新日期：2009-01-15 00:00:00

abstract：:Climate change is predicted to increase both drought frequency and duration, and when coupled with substantial warming, will establish a new hydroclimatological model for many regions. Large-scale, warm droughts have recently occurred in North America, Africa, Europe, Amazonia and Australia, resulting in major effects...

journal_title：Nature

authors： Ponce Campos GE,Moran MS,Huete A,Zhang Y,Bresloff C,Huxman TE,Eamus D,Bosch DD,Buda AR,Gunter SA,Scalley TH,Kitchen SG,McClaran MP,McNab WH,Montoya DS,Morgan JA,Peters DP,Sadler EJ,Seyfried MS,Starks PJ

更新日期：2013-02-21 00:00:00

abstract：:Kalka is one of about 14 major layered mafic-ultramafic intrusions forming the Giles Complex in central Australia1. The stratigraphical section of the Kalka Intrusion passes from a basal pyroxenite zone (450 + m) through norite and olivine gabbro zones (3,500 m) to an uppermost anorthosite zone (800 + m)2. Further res...

journal_title：Nature

authors： Gray CM,Goode ADT

更新日期：1981-11-12 00:00:00

abstract：:Hunter-Schreger bands (HSB) are seen in teeth that are composed of crossed sets of enamel prisms. They are present in the teeth of man and many other mammals, but absent in most insectivores and multituberculates. It has been suggested that the presence of HSB makes the tooth enamel less likely to split and is associa...

journal_title：Nature

authors： von Koenigswald W,Rensberger JM,Pretzschner HU

更新日期：1987-07-09 00:00:00

abstract：:The hippocampus is critical to declarative memory in humans. This kind of memory involves associations among items or events that can be accessed flexibly to guide memory expression in various and even new situations. In animals, there has been controversy about whether the hippocampus is specialized for spatial memor...

journal_title：Nature

authors： Bunsey M,Eichenbaum H

更新日期：1996-01-18 00:00:00

abstract：:Type Ia supernovae are thought to result from thermonuclear explosions of carbon-oxygen white dwarf stars. Existing models generally explain the observed properties, with the exception of the sub-luminous 1991bg-like supernovae. It has long been suspected that the merger of two white dwarfs could give rise to a type I...

journal_title：Nature

authors： Pakmor R,Kromer M,Röpke FK,Sim SA,Ruiter AJ,Hillebrandt W

更新日期：2010-01-07 00:00:00

abstract：:Io leaves a magnetic footprint on Jupiter's upper atmosphere that appears as a spot of ultraviolet emission that remains fixed underneath Io as Jupiter rotates. The specific physical mechanisms responsible for generating those emissions are not well understood, but in general the spot seems to arise because of an elec...

journal_title：Nature

authors： Clarke JT,Ajello J,Ballester G,Ben Jaffel L,Connerney J,Gérard JC,Gladstone GR,Grodent D,Pryor W,Trauger J,Waite JH Jr

更新日期：2002-02-28 00:00:00

abstract：:Milankovitch proposed that summer insolation at mid-latitudes in the Northern Hemisphere directly causes the ice-age climate cycles. This would imply that times of ice-sheet collapse should correspond to peaks in Northern Hemisphere June insolation. But the penultimate deglaciation has proved controversial because Jun...

journal_title：Nature

authors： Henderson GM,Slowey NC

更新日期：2000-03-02 00:00:00

abstract：:Various mechanisms have been proposed for beta-adrenergically mediated relaxation of smooth muscle. All theories suggest the involvement of cyclic AMP as a second messenger: beta-agonists stimulate adenylate cyclase which converts ATP to cyclic AMP and protein kinase, activated by cyclic AMP, is then thought to cataly...

journal_title：Nature

authors： Mueller E,van Breemen C

更新日期：1979-10-25 00:00:00

abstract：:Memory is believed to depend on activity-dependent changes in the strength of synapses. In part, this view is based on evidence that the efficacy of synapses can be enhanced or depressed depending on the timing of pre- and postsynaptic activity. However, when such plastic synapses are incorporated into neural network ...

journal_title：Nature

authors： Royer S,Paré D

更新日期：2003-04-03 00:00:00

abstract：:Two large-scale yeast two-hybrid screens were undertaken to identify protein-protein interactions between full-length open reading frames predicted from the Saccharomyces cerevisiae genome sequence. In one approach, we constructed a protein array of about 6,000 yeast transformants, with each transformant expressing on...

journal_title：Nature

authors： Uetz P,Giot L,Cagney G,Mansfield TA,Judson RS,Knight JR,Lockshon D,Narayan V,Srinivasan M,Pochart P,Qureshi-Emili A,Li Y,Godwin B,Conover D,Kalbfleisch T,Vijayadamodar G,Yang M,Johnston M,Fields S,Rothberg JM

更新日期：2000-02-10 00:00:00

abstract：:Antigenic variation in the haemagglutinin (HA) glycoprotein of influenza virus is associated with recurrent epidemics of respiratory disease in man (for review see ref. 1). We have examined the size of structural changes necessary to alter the antigenicity of HA by determining the three-dimensional structure of the HA...

journal_title：Nature

authors： Knossow M,Daniels RS,Douglas AR,Skehel JJ,Wiley DC

更新日期：1984-10-18 00:00:00

abstract：:The medial entorhinal cortex (MEC) is part of the brain's circuit for dynamic representation of self-location. The metric of this representation is provided by grid cells, cells with spatial firing fields that tile environments in a periodic hexagonal pattern. Limited anatomical sampling has obscured whether the grid ...

journal_title：Nature

authors： Stensola H,Stensola T,Solstad T,Frøland K,Moser MB,Moser EI

更新日期：2012-12-06 00:00:00

abstract：:Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD), a much milder form of the disease where the age of onset can sometimes be as late as the third or fourth decade of life, are caused by mutations in the same X-linked gene, a 14 kilobase (kb) transcript which is spread over more than 2 megabases of ...

journal_title：Nature

authors： England SB,Nicholson LV,Johnson MA,Forrest SM,Love DR,Zubrzycka-Gaarn EE,Bulman DE,Harris JB,Davies KE

更新日期：1990-01-11 00:00:00

abstract：:'Identifier' or ID sequences are present in 62% of the RNA polymerase II and III transcripts made in vitro from brain nuclei but in fewer than 4% of the transcripts made from the nuclei of other tissues. An homologous 160-nucleotide cytoplasmic poly(A)+ RNA species, BC1, and a smaller species, BC2, are located in vivo...

journal_title：Nature

authors： Sutcliffe JG,Milner RJ,Gottesfeld JM,Lerner RA

更新日期：1984-03-15 00:00:00

abstract：:Recent studies have shown that normal cellular sequences on chromosome 13 are lost during the development of retinoblastomas and that sequences on chromosome 11 are similarly lost during the development of Wilms' kidney tumours and embryonal tumours. Cells from these tumors have been found to contain either the patern...

journal_title：Nature

authors： Fearon ER,Feinberg AP,Hamilton SH,Vogelstein B

更新日期：1985-11-28 00:00:00

abstract：:Calcium signalling in astrocytes couples changes in neural activity to alterations in cerebral blood flow by eliciting vasoconstriction or vasodilation of arterioles. However, the mechanism for how these opposite astrocyte influences provide appropriate changes in vessel tone within an environment that has dynamic met...

journal_title：Nature

authors： Gordon GR,Choi HB,Rungta RL,Ellis-Davies GC,MacVicar BA

更新日期：2008-12-11 00:00:00

abstract：:Hypogonadism in the mutant hpg mouse is characterized by a deficiency of hypothalamic gonadotropin releasing hormone (GnRH). Affected male mice exhibit immature reproductive organs, small abdominal testes and low pituitary and plasma gonadotropin concentrations. Recent studies have demonstrated the potential of fetal ...

journal_title：Nature

authors： Krieger DT,Perlow MJ,Gibson MJ,Davies TF,Zimmerman EA,Ferin M,Charlton HM

更新日期：1982-07-29 00:00:00

abstract：:Climate strongly affects the production of sediment from mountain catchments as well as its transport and deposition within adjacent sedimentary basins. However, identifying climatic influences on basin stratigraphy is complicated by nonlinearities, feedback loops, lag times, buffering and convergence among processes ...

journal_title：Nature

authors： Foreman BZ,Heller PL,Clementz MT

更新日期：2012-11-01 00:00:00

abstract：:The hydroxyl radical (OH) is a key oxidant involved in the removal of air pollutants and greenhouse gases from the atmosphere. The ratio of Northern Hemispheric to Southern Hemispheric (NH/SH) OH concentration is important for our understanding of emission estimates of atmospheric species such as nitrogen oxides and m...

journal_title：Nature

authors： Patra PK,Krol MC,Montzka SA,Arnold T,Atlas EL,Lintner BR,Stephens BB,Xiang B,Elkins JW,Fraser PJ,Ghosh A,Hintsa EJ,Hurst DF,Ishijima K,Krummel PB,Miller BR,Miyazaki K,Moore FL,Mühle J,O'Doherty S,Prinn RG,Steele

更新日期：2014-09-11 00:00:00

abstract：:Calcium (Ca(2+))-activated chloride channels are fundamental mediators in numerous physiological processes including transepithelial secretion, cardiac and neuronal excitation, sensory transduction, smooth muscle contraction and fertilization. Despite their physiological importance, their molecular identity has remain...

journal_title：Nature

authors： Yang YD,Cho H,Koo JY,Tak MH,Cho Y,Shim WS,Park SP,Lee J,Lee B,Kim BM,Raouf R,Shin YK,Oh U

更新日期：2008-10-30 00:00:00

abstract：:Little is known about metabolic regulation in stem cells and how this modulates tissue regeneration or tumour suppression. We studied the Lkb1 tumour suppressor and its substrate AMP-activated protein kinase (AMPK), kinases that coordinate metabolism with cell growth. Deletion of the Lkb1 (also called Stk11) gene in m...

journal_title：Nature

authors： Nakada D,Saunders TL,Morrison SJ

更新日期：2010-12-02 00:00:00