Abstract:
:We present here a shorter version of the proof of our earlier work, showing that the von Neumann factor associated with the group Z(2)SL(2,Z) has trivial fundamental group.
journal_name
Proc Natl Acad Sci U S Aauthors
Popa Sdoi
10.1073/pnas.2333960100keywords:
subject
Has Abstractpub_date
2004-01-20 00:00:00pages
723-6issue
3eissn
0027-8424issn
1091-6490pii
2333960100journal_volume
101pub_type
杂志文章abstract::Intrinsically disordered proteins (IDPs) are involved in a wide range of regulatory processes in the cell. Owing to their flexibility, their conformations are expected to be particularly sensitive to the crowded cellular environment. Here we use single-molecule Förster resonance energy transfer to quantify the effect ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.1322611111
更新日期:2014-04-01 00:00:00
abstract::A simple in vitro system that supports chromatin assembly was developed for Saccharomyces cerevisiae. The assembly reaction is ATP-dependent, uses soluble histones and assembly factors, and generates physiologically spaced nucleosomes. We analyze the pathway of histone recruitment into nucleosomes, using this system i...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.94.17.9034
更新日期:1997-08-19 00:00:00
abstract::RNA 3'-phosphate cyclase (RtcA) synthesizes RNA 2',3' cyclic phosphate ends via three steps: reaction with ATP to form a covalent RtcA-(histidinyl-Nε)-AMP intermediate; transfer of adenylate to an RNA 3'-phosphate to form RNA(3')pp(5')A; and attack of the vicinal O2' on the 3'-phosphorus to form a 2',3' cyclic phospha...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.1115560108
更新日期:2011-12-27 00:00:00
abstract::Molecular weights of the isolated proteins from the 30S and 50S ribosomal subunits of Escherichia coli were determined by two independent methods: polyacrylamide gel electrophoresis with sodium dodecylsulphate and equilibrium sedimentation. The values for the molecular weights determined by gel electrophoresis range f...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.67.4.1909
更新日期:1970-12-01 00:00:00
abstract::A segment of DNA containing cya, the gene for adenylate cyclase [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1], has been isolated from Salmonella typhimurium. The phage lambda gt4 was used as a cloning vector and adenylate cyclase-positive hybrid phages were isolated that complemented adenylate cyclase-negative bac...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.78.8.4684
更新日期:1981-08-01 00:00:00
abstract::Proteolytic removal of the pre-segment from growing nascent chains of pre-human placental lactogen (hPL) occurred during in vitro translation of placental mRNA if crude membranes derived from ascites lysates, dog pancreas, or rat liver rough endoplasmic reticulum were added to the translation mixtures. The cotranslati...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.76.9.4225
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abstract::The cell-surface antigen detected by the monoclonal antibody JONES is expressed in the retina and a number of other central nervous system regions of the rat during the latter part of embryonic development and the early postnatal period. In addition to the expression on certain neuroblast populations it is found on so...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.84.23.8716
更新日期:1987-12-01 00:00:00
abstract::Multiple biological processes involve the stretching of nucleic acids (NAs). Stretching forces induce local changes in the molecule structure, inhibiting or promoting the binding of proteins, which ultimately affects their functionality. Understanding how a force induces changes in the structure of NAs at the atomic l...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2017-07-03 00:00:00
abstract::RNA viruses are notorious for their genetic plasticity and propensity to exploit new host-range opportunities, which can lead to the emergence of human disease epidemics such as severe acute respiratory syndrome, AIDS, dengue, and influenza. However, the mechanisms of host-range change involved in most of these viral ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0509961103
更新日期:2006-03-28 00:00:00
abstract::Treatment of human fibroblast cells with human fibroblast (beta)interferon for up to 8 hr resulted in the accumulation of at least four mRNAs. The mRNAs were isolated from cellular polysomes and characterized by stimulation of translation in a wheat germ cell-free protein synthesis system. The mRNAs appear as early as...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.78.8.4763
更新日期:1981-08-01 00:00:00
abstract::Lizards and snakes putatively arose between the early Jurassic and late Triassic; they diversified worldwide and now occupy many different ecological niches, making them ideal for testing theories on the origin of ecological traits. We propose and test the "deep history hypothesis," which claims that differences in ec...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0501104102
更新日期:2005-05-31 00:00:00
abstract::The Drosophila clock genes period (per) and timeless (tim) have been studied behaviorally and biochemically, but to date there has been no viable culture system for studying the cell biology of the Drosophila clock. We have cultured pupal ring glands attached to the central nervous system and observed rhythms of perio...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.94.8.4092
更新日期:1997-04-15 00:00:00
abstract::Calcium sensitivity of myosin cross-bridge activation in striated muscles commonly varies during ontogeny and in response to alterations in muscle usage, but the consequences for whole-organism physiology are not well known. Here we show that the relative abundances of alternatively spliced transcripts of the calcium ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.96.26.15304
更新日期:1999-12-21 00:00:00
abstract::Rhomboid domain-containing protein 3 (Rhbdd3), which belongs to a family of proteins with rhomboid domain, is widely expressed in immune cells; however, the roles of the Rhbdd members, including Rhbdd3, in immunity remain unknown. Natural killer (NK) cells are critical for host immune defense and also can mediate infl...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1220466110
更新日期:2013-05-07 00:00:00
abstract::Thioredoxin (Trx) is an intracellular redox protein with extracellular cytokine-like and chemokine-like activities. We show here that, although plasma Trx levels are unrelated to survival of HIV-infected individuals with CD4 cell counts above 200/microl blood, survival is significantly impaired (P = 0.003) when plasma...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.041624998
更新日期:2001-02-27 00:00:00
abstract::Excitotoxicity, resulting from sustained activation of glutamate receptors of the N-methyl-d-aspartate (NMDA) subtype, is considered to play a causative role in the etiology of ischemic stroke and several neurodegenerative diseases. The NMDA receptor is therefore a target for the development of neuroprotective agents....
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.061449498
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2019-04-23 00:00:00
abstract::Communication about prescription drugs ought to be a paragon of public science communication. Unfortunately, it is not. Consumers see $4 billion of direct-to-consumer advertising annually, which typically fails to present data about how well drugs work. The professional label--the Food and Drug Administration's (FDA) ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2011-01-18 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1620508114
更新日期:2017-03-21 00:00:00
abstract::Thermotaxis by individual amoebae of Dictyostelium discoideum on a temperature gradient is described. These amoebae show positive thermotaxis at temperatures between 14 degrees C and 28 degrees C shortly (3 hr) after food depletion. Increasing time on the gradient reduces the positive thermotactic response at the lowe...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1983-09-01 00:00:00
abstract::A stable complex between pentaammineruthenium(III) and histidine-33 in horse heart ferricytochrome c is formed in the reaction between aquopentaammineruthenium(II) and the protein at pH 7. HPLC of the tryptic hydrolysate of the modified protein was employed to identify the pentaammineruthenium binding site. Spectrosco...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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abstract::GT-2 is a plant transcriptional activator that contains two separate, but similar, trihelix DNA-binding domains. GT-1 is similar to GT-2, although it contains only one of such domains. cDNAs that encode GT-2 were isolated from rice (OS-GT2) and Arabidopsis (AT-GT2). Evidence is presented for the existence of an Arabid...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::Large quantities of mineral dust particles are frequently ejected into the atmosphere through the action of wind. The surface of dust particles acts as a sink for many gases, such as sulfur dioxide. It is well known that under most conditions, sulfur dioxide reacts on dust particle surfaces, leading to the production ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2012-12-18 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2011-01-25 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1505515112
更新日期:2015-07-07 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.75.11.5732
更新日期:1978-11-01 00:00:00
abstract::Expression of the bovine papillomavirus E2 regulatory protein in human cervical carcinoma cell lines repressed expression of the resident human papillomavirus E6 and E7 oncogenes and within a few days caused essentially all of the cells to synchronously display numerous phenotypic markers characteristic of cells under...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.97.20.10978
更新日期:2000-09-26 00:00:00
abstract::The synaptonemal complex (SC) is a conserved meiotic structure that regulates the repair of double-strand breaks (DSBs) into crossovers or gene conversions. The removal of any central-region SC component, such as the Drosophila melanogaster transverse filament protein C(3)G, causes a complete loss of SC structure and ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1910840116
更新日期:2019-10-22 00:00:00