Abstract:
:The present study investigated whether neural structures become less functionally differentiated and specialized with age. We studied ventral visual cortex, an area of the brain that responds selectively to visual categories (faces, places, and words) in young adults, and that shows little atrophy with age. Functional MRI was used to estimate neural activity in this cortical area, while young and old adults viewed faces, houses, pseudowords, and chairs. The results demonstrated significantly less neural specialization for these stimulus categories in older adults across a range of analyses.
journal_name
Proc Natl Acad Sci U S Aauthors
Park DC,Polk TA,Park R,Minear M,Savage A,Smith MRdoi
10.1073/pnas.0405148101keywords:
subject
Has Abstractpub_date
2004-08-31 00:00:00pages
13091-5issue
35eissn
0027-8424issn
1091-6490pii
0405148101journal_volume
101pub_type
杂志文章abstract::Kabuki syndrome is a Mendelian intellectual disability syndrome caused by mutations in either of two genes (KMT2D and KDM6A) involved in chromatin accessibility. We previously showed that an agent that promotes chromatin opening, the histone deacetylase inhibitor (HDACi) AR-42, ameliorates the deficiency of adult neur...
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.1611431114
更新日期:2017-01-03 00:00:00
abstract::Intact squid axons were injected with aequorin and bathed in 3 mM Ca seawater (a concentration close to that of squid blood). Sodium and potassium currents were pharmacologically blocked and repetitive voltage-clamp pulses of a duration of 1.5 ms were applied (to simulate the duration of an action potential) at amplit...
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.82.6.1847
更新日期:1985-03-01 00:00:00
abstract::The body-wall muscle cells of the nematode Caenorhabditis elegans produce thick filaments during embryonic, larval, and adult stages. These thick filaments contain two myosin isoforms, A and B, which assemble into different zones along the 10-microns lengths. Paramyosin, a protein homologous to myosin rods, forms a su...
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.87.3.876
更新日期:1990-02-01 00:00:00
abstract::During the last several decades corals have been in decline and at least one-third of all coral species are now threatened with extinction. Coral disease has been a major contributor to this threat, but little is known about the responsible pathogens. To date most research has focused on bacterial and fungal diseases;...
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.0808985105
更新日期:2008-11-25 00:00:00
abstract::Drosophila melanogaster is a powerful model organism for dissecting the neurogenetic basis of appetitive and aversive behaviors. However, some methods used to assay food preference require or cause starvation. This can be problematic for fly ethanol research because it can be difficult to dissociate caloric preference...
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.1716880115
更新日期:2018-09-04 00:00:00
abstract::For the purpose of clarifying the magneto-orientation mechanism of several biological membrane systems, xylene-suspended thin-layered single crystals of lecithin, which is a major component of membranes, were subjected to magnetic fields of various strengths, and the orientation behavior of the crystals was analyzed. ...
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.77.12.7232
更新日期:1980-12-01 00:00:00
abstract::The DNA polymerase enzymes from avian, murine, and feline RNA tumor viruses can be distinguished by their ability to read specific, synthetic primertemplates. The copying of templates containing adenylic and thymidylic acids by all these DNA polymerases is inhibited by ethidium bromide, though this compound affects th...
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.68.12.3116
更新日期:1971-12-01 00:00:00
abstract::A methylcholanthrene-induced glioblastoma of the C57BL/6 inbred mouse strain was used to raise antibodies in C57BL/6 and C57BL/10 inbred mice and in (C57BL/6 x DBA/2) and (C57BL/6 x Balb/c) F(1) hybrids. When examined by the cytotoxicity test, these antibodies define a cell-surface component (or components) found excl...
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.71.5.1795
更新日期:1974-05-01 00:00:00
abstract::The content of elongation factor Tu in E. coli B has been determined both by radioimmune assay and by GDP binding. The two assays gave comparable results: cells growing at 2 doublings per hour contained about 8 molecules of Tu per ribosome, whereas those growing at 0.22 doublings per hour contained about 14 molecules ...
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.72.12.4780
更新日期:1975-12-01 00:00:00
abstract::A procedure is described for selection of temperature-sensitive mutants affecting fatty-acid synthesis based upon radiation suicide of wild-type organisms by tritiated acetate selectively incorporated into fatty acids. At 37 degrees , two of the mutants extensively incorporate fatty-acid supplements provided in the 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.69.11.3105
更新日期:1972-11-01 00:00:00
abstract::Identification of the consensus sequence for termination of replication (ter) in Escherichia coli and the isolation of the ter-binding protein (TBP) allowed us to test their effects on replication forks initiated at the unique origin of the E. coli chromosome (oriC) in a purified enzyme system. Replication was severel...
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.86.23.9104
更新日期:1989-12-01 00:00:00
abstract::Gene therapy of the brain is hindered by the presence of the blood-brain barrier (BBB), which prevents the brain uptake of bloodborne gene formulations. Exogenous genes have been expressed in the brain after invasive routes of administration, such as craniotomy or intracarotid arterial infusion of noxious agents causi...
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.130187497
更新日期:2000-06-20 00:00:00
abstract::Indoor residual spraying (IRS) is used to control visceral leishmaniasis (VL) in India, but it is poorly quality assured. Quality assurance was performed in eight VL endemic districts in Bihar State, India, in 2014. Residual dichlorodiphenyltrichloroethane (DDT) was sampled from walls using Bostik tape discs, and DDT ...
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.1507782112
更新日期:2015-07-14 00:00:00
abstract::Proteasome activator PA200 enhances proteasome-mediated cleavage after acidic residues in vitro; however, its role within cells is not known. Here, we show that, in response to ionizing radiation, PA200 forms hybrid proteasomes with 19S caps and 20S core proteasomes that accumulate on chromatin, leading to an increase...
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.0803145105
更新日期:2008-10-21 00:00:00
abstract::New neurons are continuously generated in restricted regions of the adult mammalian brain. Although these adult-born neurons have been shown to receive synaptic inputs, little is known about their synaptic outputs. Using retrovirus-mediated birth-dating and labeling in combination with serial section electron microsco...
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.0806658105
更新日期:2008-09-16 00:00:00
abstract::3-Hydroxyanthranilic acid (HAA), a compound generated during tryptophan metabolism initiated by indoleamine 2,3-dioxygenase, is known to induce T cell death, but its molecular target is not known. Here we report that HAA inhibits NF-kappaB activation upon T cell antigen receptor engagement by specifically targeting PD...
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.0709261104
更新日期:2007-11-20 00:00:00
abstract::The IgG2a monoclonal antibody TH-1, which reacts specifically with blood group A1 but with neither A2 nor O erythrocytes, has been established. The antibody reacted only with A1 erythrocytes in hemagglutination and antibody absorption assays; it did not react with A2 erythrocytes, even after trypsin or sialidase treat...
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.82.4.1199
更新日期:1985-02-01 00:00:00
abstract::Dynamic fluxes of s-block metals like potassium, sodium, and calcium are of broad importance in cell signaling. In contrast, the concept of mobile transition metals triggered by cell activation remains insufficiently explored, in large part because metals like copper and iron are typically studied as static cellular 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.1009932108
更新日期:2011-04-12 00:00:00
abstract::The human epidermal growth factor receptor 2 (HER2) is specifically overexpressed in tumors of several cancers, including an aggressive form of breast cancer. It is therefore a target for both cancer diagnostics and therapy. The 58 amino acid residue Zher2 affibody molecule was previously engineered as a high-affinity...
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.1005025107
更新日期:2010-08-24 00:00:00
abstract::The HB-19 pseudopeptide 5[Kpsi(CH(2)N)PR]-TASP, psi(CH(2)N) for reduced peptide bond, is a specific inhibitor of HIV infection in different CD4(+) cell lines and in primary T-lymphocytes and macrophages. It blocks virus-particle attachment to permissive cells by binding and forming a stable complex with nucleolin expr...
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.221467298
更新日期:2001-11-20 00:00:00
abstract::The effects of the thymic polypeptide thymopoietin (Tpo) on the properties of the nicotinic acetylcholine receptor (AcChoR) were investigated by patch clamp techniques on mouse C2 myotubes and by biochemical assays on AcChoR-rich membrane fragments purified from the Torpedo marmorata electric organ. At high concentrat...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,收录出版
doi:10.1073/pnas.84.10.3477
更新日期:1987-05-01 00:00:00
abstract::Unit-resolution mass spectra have been obtained for peptides as large as 17 kDa, providing information on impurities and adduct ions, as well as accurate molecular weight values. Electrospray ionization produces many multiply-charged species of the same mass; isotopic peak resolution provides direct charge state assig...
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.89.1.286
更新日期:1992-01-01 00:00:00
abstract::Meiotic mutant (2n) gametes formed by first-division restitution without crossover (FDR-NCO) are expected to be superior to FDR with crossover (FDR-CO) because they transmit to the progeny, without disruption by recombination, almost 100% of the parental genotype. FDR-CO transfers approximately 80% of the parental het...
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.96.4.1773
更新日期:1999-02-16 00:00:00
abstract::We study inverse statistical mechanics: how can one design a potential function so as to produce a specified ground state? In this article, we show that unexpectedly simple potential functions suffice for certain symmetrical configurations, and we apply techniques from coding and information theory to provide mathemat...
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.0901636106
更新日期:2009-06-16 00:00:00
abstract::Compensatory ventilatory responses to increased inspiratory loading are essential for adequate breathing regulation in a number of pulmonary diseases; however, the human brain sites mediating such responses are unknown. Midsagittal and axial images were acquired in 11 healthy volunteers during unloaded and loaded (30 ...
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.92.14.6607
更新日期:1995-07-03 00:00:00
abstract::Genetic data in the mouse have shown that endothelin 3 (ET3) and its receptor B (ETRB) are essential for the development of two neural crest (NC) derivatives, the melanocytes and the enteric nervous system. We report here the effects of ET3 in vitro on the differentiation of quail trunk NC cells (NCC) in mass and clon...
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.95.24.14214
更新日期:1998-11-24 00:00:00
abstract::The putative oxidation of hydroethidine (HE) has become a widely used fluorescent assay for the detection of superoxide in cultured cells. By covalently joining HE to a hexyl triphenylphosphonium cation (Mito-HE), the HE moiety can be targeted to mitochondria. However, the specificity of HE and Mito-HE for superoxide ...
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.0601945103
更新日期:2006-10-10 00:00:00
abstract::We investigate yeast sex chromosome evolution by comparing genome sequences from 16 species in the family Saccharomycetaceae, including data from genera Tetrapisispora, Kazachstania, Naumovozyma, and Torulaspora. We show that although most yeast species contain a mating-type (MAT) locus and silent HML and HMR loci str...
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.1112808108
更新日期:2011-12-13 00:00:00
abstract::Bacteriophage lambda encodes a number of genes involved in the recombinational repair of DNA double-strand breaks. The product of one of these genes, rap, has been purified. Truncated Rap proteins that copurify with the full-length form are derived, at least in part, from a rho-dependent transcription terminator locat...
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.95.23.13507
更新日期:1998-11-10 00:00:00
abstract::Ribavirin is a nucleotide analog that can be incorporated by viral polymerases, causing mutations by allowing base mismatches. It is currently used therapeutically as an antiviral drug during hepatitis C virus infections. During the amplification of poliovirus genomic RNA or hepatitis C replicons, error frequency is k...
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.1232294100
更新日期:2003-06-10 00:00:00