Abstract:
:There are many occasions in which humans and other animals must inhibit the production of some behavior or inhibit the processing of some internal representation. Success in inhibitory processing under normal circumstances can be revealed by the fact that certain brain pathologies render inhibitory processing ineffective. These pathologies often have been associated with damage to frontal cortex, including lateral and inferior aspects. We provide behavioral evidence of a verbal working memory task that, by hypothesis, engaged inhibitory processing, and we show (by using positron emission tomograpny) that the inhibitory processing is associated with a lateral portion of the left prefrontal cortex. The task in which subjects engaged was item-recognition: Four target letters were presented for storage followed, after a brief interval, by a probe letter that could match a target letter or not. On some trials, when the probe did not match a target letter and therefore required a "no" response, the probe had matched a target letter of the previous trial, so on these trials a "yes" response was prepotent and had to be inhibited, by hypothesis. Compared with a condition in which no prepotent response was created, this condition yielded brain activation in left inferior frontal gyrus, in the region of Brodmann's area 45.
journal_name
Proc Natl Acad Sci U S Aauthors
Jonides J,Smith EE,Marshuetz C,Koeppe RA,Reuter-Lorenz PAdoi
10.1073/pnas.95.14.8410subject
Has Abstractpub_date
1998-07-07 00:00:00pages
8410-3issue
14eissn
0027-8424issn
1091-6490journal_volume
95pub_type
杂志文章abstract::We present a proposition, the "poly(L-alanine) hypothesis," which asserts that the native backbone geometry for any polypeptide or protein of M residues has a closely mimicking, mechanically stable, image in poly(L-alanine) of the same number of residues. Using a molecular mechanics force field to represent the releva...
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.89.23.11513
更新日期:1992-12-01 00:00:00
abstract::The problem of Congressional apportionment is explained together with a brief history of the methods used or considered for its solution. Reasons are given for rejecting the presently used method of equal proportions and for accepting a new method, the quota method, which is the unique method satisfying three essentia...
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.71.11.4602
更新日期:1974-11-01 00:00:00
abstract::Loss of IκB kinase (IKK) β-dependent NF-κB signaling in hematopoietic cells is associated with increased granulopoiesis. Here we identify a regulatory cytokine loop that causes neutrophilia in Ikkβ-deficient mice. TNF-α-dependent apoptosis of myeloid progenitor cells leads to the release of IL-1β, which promotes Th17 ...
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.1018331108
更新日期:2011-04-19 00:00:00
abstract::Myosins are molecular motors that power diverse cellular processes, such as rapid organelle transport, muscle contraction, and tension-sensitive anchoring. The structural adaptations in the motor that allow for this functional diversity are not known, due, in part, to the lack of high-resolution structures of highly t...
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.1321022111
更新日期:2014-02-11 00:00:00
abstract::A-kinase anchoring proteins (AKAPs) shape second-messenger signaling responses by constraining protein kinase A (PKA) at precise intracellular locations. A defining feature of AKAPs is a helical region that binds to regulatory subunits (RII) of PKA. Mining patient-derived databases has identified 42 nonsynonymous SNPs...
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.1816614115
更新日期:2018-12-04 00:00:00
abstract::High-entropy alloys are made from random mixtures of principal elements on simple lattices, stabilized by a high mixing entropy. The recently discovered body-centered cubic (BCC) Ta-Nb-Hf-Zr-Ti high-entropy alloy superconductor appears to display properties of both simple crystalline intermetallics and amorphous mater...
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.1615926113
更新日期:2016-11-15 00:00:00
abstract::A sensitive assay for detection of eukaryotic RNA polymerase II has been developed. This assay depends on the ability of polymerase II to elongate a small RNA primer, oligo(U), hybridized to a single-stranded homopolymeric DNA template, poly(dA). The poly(dA).oligo(U)-dependent RNA polymerase II from calf thymus has b...
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.82.23.7979
更新日期:1985-12-01 00:00:00
abstract::Marine ecosystems are in decline. New transformational changes in governance are urgently required to cope with overfishing, pollution, global changes, and other drivers of degradation. Here we explore social, political, and ecological aspects of a transformation in governance of Chile's coastal marine resources, from...
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.1012021107
更新日期:2010-09-28 00:00:00
abstract::Rat beta-lipotropin was isolated from 40 anterior pituitaries using high efficiency chromatography columns and sensitive fluorometric methods. The beta-lipotropin was characterized as to molecular weight, amino acid composition, and generation of opioid activity by trypsinization. Other opioid peptides, as well as a p...
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.74.7.3052
更新日期:1977-07-01 00:00:00
abstract::Ants are the world's most conspicuous and important eusocial insects and their diversity, abundance, and extreme behavioral specializations make them a model system for several disciplines within the biological sciences. Here, we report the discovery of a new ant that appears to represent the sister lineage to all ext...
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.0806187105
更新日期:2008-09-30 00:00:00
abstract::Identifying presynaptic mechanisms of general anesthetics is critical to understanding their effects on synaptic transmission. We show that the volatile anesthetic isoflurane inhibits synaptic vesicle (SV) exocytosis at nerve terminals in dissociated rat hippocampal neurons through inhibition of presynaptic Ca(2+) inf...
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.1500525112
更新日期:2015-09-22 00:00:00
abstract::Identifying targets is critical for understanding the biological effects of microRNA (miRNA) expression. The challenge lies in characterizing the cohort of targets for a specific miRNA, especially when targets are being actively down-regulated in miRNA- RNA-induced silencing complex (RISC)-messengerRNA (mRNA) complexe...
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.1218887109
更新日期:2012-12-11 00:00:00
abstract::For many agronomically important plant genes, only their position on a genetic map is known. In the absence of an efficient transposon tagging system, such genes have to be isolated by map-based cloning. In bread wheat Triticum aestivum, the genome is hexaploid, has a size of 1.6 x 10(10) bp, and contains more than 80...
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.230361597
更新日期:2000-11-21 00:00:00
abstract::Light chain allotypic determinants were demonstrated on the surface of peripheral blood lymphocytes of rabbits. By means of a combined immunofluorescent and autoradiographic technique, a great majority of the individual lymphocytes of rabbits heteroxygous at the b locus were shown to have detectable quantities of only...
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.68.2.430
更新日期:1971-02-01 00:00:00
abstract::Intergroup conflict persists when and because individuals make costly contributions to their group's fighting capacity, but how groups organize contributions into effective collective action remains poorly understood. Here we distinguish between contributions aimed at subordinating out-groups (out-group aggression) fr...
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.1605115113
更新日期:2016-09-20 00:00:00
abstract::The heptadecapeptide orphanin FQ (OFQ) is a recently discovered neuropeptide that exhibits structural features reminiscent of the opioid peptides and that is an endogenous ligand to a G protein-coupled receptor sequentially related to the opioid receptors. We have cloned both the human and rat cDNAs encoding the OFQ p...
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.93.16.8677
更新日期:1996-08-06 00:00:00
abstract::The thymus lacks self-renewing hematopoietic cells, and thymopoiesis fails rapidly when the migration of progenitor cells to the thymus ceases. Hence, the process of thymus homing is an essential step for T-cell development and cellular immunity. Despite decades of research, the molecular details of thymus homing have...
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.1016428108
更新日期:2011-05-03 00:00:00
abstract::A single-nucleotide polymorphism in the human arylamine N-acetyltransferase 2 (Nat2) gene has recently been identified as associated with insulin resistance in humans. To understand the cellular and molecular mechanisms by which alterations in Nat2 activity might cause insulin resistance, we examined murine ortholog N...
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.1716990115
更新日期:2017-12-26 00:00:00
abstract::Arsenate is an abundant oxyanion that, because of its ability to mimic the phosphate group, is toxic to cells. Arsenate reductase (EC; encoded by the arsC gene in bacteria) participates to achieve arsenate resistance in both prokaryotes and yeast by reducing arsenate to arsenite; the arsenite is then exported by a spe...
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.241397198
更新日期:2001-11-20 00:00:00
abstract::Steroidogenic factor-1 (SF-1) and liver receptor homologue-1 (LRH-1) belong to the fushi tarazu factor 1 subfamily of nuclear receptors. SF-1 is an essential factor for sex determination during development and regulates adrenal and gonadal steroidogenesis in the adult, whereas LRH-1 is a critical factor for developmen...
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.0409482102
更新日期:2005-05-24 00:00:00
abstract::We examine the quantum confinement in the photoemission ionization energy in air and optical band gap of carbon nanoparticles (CNPs). Premixed, stretched-stabilized ethylene flames are used to generate the CNPs reproducibly over the range of 4-23 nm in volume median diameter. The results reveal that flame-formed CNPs ...
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.1900205116
更新日期:2019-06-25 00:00:00
abstract::Let Lambda=SL(2)(Z) be the modular group and let c(n)(Lambda) be the number of congruence subgroups of Lambda of index at most n. We prove that lim(n--> infinity )(log c(n)(Lambda)/((log n)(2)/log log n))=(3-2(sqrt)2)/4. The proof is based on the Bombieri-Vinogradov "Riemann hypothesis on the average" and on the solut...
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.0404571101
更新日期:2004-09-14 00:00:00
abstract::A panel of rat monoclonal antibodies was used to classify mouse mast cells from four different sources on the basis of their surface determinants. Three populations of mast cells were derived by culturing normal bone marrow, spleen, and peripheral blood cells, whereas the fourth population was isolated directly from t...
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.80.19.5916
更新日期:1983-10-01 00:00:00
abstract::The structures of human platelet alpha 2-adrenergic receptors and rat liver alpha 1-adrenergic receptors were compared by utilizing isoelectric focusing, NaDodSO4/PAGE, and monoclonal antibody crossreactivity. Digitonin-solubilized alpha 1- and alpha 2-adrenergic receptors have an identical isoelectric point of 4.6. U...
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.82.14.4842
更新日期:1985-07-01 00:00:00
abstract::Heme A is an essential cofactor for respiratory terminal oxidases and vital for respiration in aerobic organisms. The final step of heme A biosynthesis is formylation of the C-8 methyl group of heme molecule by heme A synthase (HAS). HAS is a heme-containing integral membrane protein, and its structure and reaction me...
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.1813346115
更新日期:2018-11-20 00:00:00
abstract::Syringomycin, a peptide toxin and a virulence factor produced by the bacterial phytopathogen Pseudomonas syringae pv. syringae, stimulated the phosphorylation of several plasma membrane polypeptides of red beet storage tissue. Among these was a 100-kDa polypeptide, which corresponds in size to the proton pump ATPase. ...
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.84.19.6755
更新日期:1987-10-01 00:00:00
abstract::In this paper we demonstrate that near infrared Fourier transform Raman spectroscopy provides unprecedented biochemical information about the extent of atherosclerosis in human aorta. In particular, elastin, collagen, cholesterol, cholesterol esters, lipids, carotenoids, and calcium apatite deposits all can be discern...
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.89.8.3473
更新日期:1992-04-15 00:00:00
abstract::The effect of x-rays on the rate of semiconservative DNA replication was investigated by autoradiography in single cells obtained from normal individuals and from patients having ataxia-telangiectasia (AT). In the five AT cell strains studied, the rate of DNA synthesis was inhibited to a lesser extent that in two norm...
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.79.8.2641
更新日期:1982-04-01 00:00:00
abstract::A protein that specifically binds leukemia inhibitory factor (LIF) has been isolated from normal mouse serum by using four successive fractionation steps: chromatography on a LIF affinity matrix, anion-exchange chromatography, size-exclusion chromatography, and preparative native gel electrophoresis. The purified LIF-...
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.89.18.8616
更新日期:1992-09-15 00:00:00
abstract::The MYC family of cellular oncogenes includes c-Myc, N-myc, and L-myc, which encode transcriptional regulators involved in the control of cell proliferation and death. Accordingly, these genes become aberrantly activated and expressed in specific types of cancers. For example, c-Myc translocations occur frequently in ...
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.0812763106
更新日期:2009-02-17 00:00:00