Abstract:
:We studied regional cerebral blood flow using the H2(15)O method while normal subjects performed four similar tasks involving three-letter word beginnings (stems). Prior to each task, subjects studied a list of words. Local blood flow was then monitored during a 40-sec period while subjects (i) silently viewed word stems, (ii) completed stems to form the first words to come to mind, but the stems were not the beginnings of any study words (baseline), (iii) completed stems and half of them could form study words (priming), or (iv) tried to recall study words, and half of the stems could form these words (memory). There were three major findings. (i) The memory task engaged the right hippocampal region when the memory task was compared to either the baseline or the priming condition. The right hemispheric locus suggests that performance is driven by the visual characteristics of the words rather than by semantic or phonetic analysis. (ii) In the priming-minus-baseline comparison, there was reduction in blood flow in the right posterior cortex. (iii) Right prefrontal cortex was activated in the memory-minus-baseline condition. The results provide evidence for selective activation of the human hippocampal region in association with memory function. The results also lead to a suggestion about the neural basis of repetition priming: following presentation of a stimulus, less neural activity is required to process the same stimulus.
journal_name
Proc Natl Acad Sci U S Aauthors
Squire LR,Ojemann JG,Miezin FM,Petersen SE,Videen TO,Raichle MEdoi
10.1073/pnas.89.5.1837keywords:
subject
Has Abstractpub_date
1992-03-01 00:00:00pages
1837-41issue
5eissn
0027-8424issn
1091-6490journal_volume
89pub_type
杂志文章abstract::The process by which cells select one of several specific programs of genetic information in development was examined in homoeotic mutant Antennapedia of Rappaport in Drosophila melanogaster. The results show that the alteration of determination from antenna to leg induced by this homoeotic mutation occurs in a popula...
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.64.1.176
更新日期:1969-09-01 00:00:00
abstract::Deficiency in PTEN (phosphatase and tensin homolog deleted on chromosome 10) is the underlying cause of PTEN hamartoma tumor syndrome and a wide variety of human cancers. In skin epidermis, we have previously identified an autocrine FGF signaling induced by loss of Pten in keratinocytes. In this study, we demonstrate ...
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.1604450113
更新日期:2016-11-15 00:00:00
abstract::Hypoxia-inducible factor-1 (HIF-1) plays an essential role in tumor development and progression by regulating genes that are vital for proliferation, glycolysis, angiogenesis, and metastasis. To identify strategies of targeting the HIF-1 pathway, we screened a siRNA library against the entire druggable genome and a sm...
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.0706585104
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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.90.7.2784
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abstract::The binding of interferons to distinct cell surface receptors leads to the induction of synthesis of several unique polypeptides and their corresponding mRNAs (1-6). We have isolated two cDNAs that are complementary to nuclear RNA whose synthesis is induced from undetectable levels to maximal rates of transcription wi...
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.81.21.6733
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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.76.12.6515
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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.90.19.9095
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abstract::Under steady-state conditions, the immune system is poised to sense and respond to the microbiota. As such, immunity to the microbiota, including T cell responses, is expected to precede any inflammatory trigger. How this pool of preformed microbiota-specific T cells contributes to tissue pathologies remains unclear. ...
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
doi:10.1073/pnas.66.3.975
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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:2014-03-11 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.70.2.531
更新日期:1973-02-01 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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更新日期:2000-10-24 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.84.8.2401
更新日期:1987-04-01 00:00:00
abstract::A cDNA sequence coding for murine granulocyte colony-stimulating factor (G-CSF) has been isolated from a cDNA library prepared with mRNA derived from murine fibrosarcoma NFSA cells, which produce G-CSF constitutively. Identification of murine G-CSF cDNA was based on the cross-hybridization with human G-CSF cDNA 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.83.20.7633
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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.79.15.4645
更新日期:1982-08-01 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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更新日期:1982-12-01 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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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
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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:1982-12-01 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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更新日期:2003-02-18 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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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:2015-11-24 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.72.8.3176
更新日期:1975-08-01 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.0401401101
更新日期:2004-04-27 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.83.13.4631
更新日期:1986-07-01 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.251547598
更新日期:2001-12-04 00:00:00
abstract::Clathrin-coated vesicles are known to be involved in the transport of proteins from the Golgi to the vacuole in plant cells. The mechanisms by which proteins are directed into this pathway are not known. Here we identify an integral membrane protein of approximately 80 kDa, extracted from clathrin-coated vesicles of d...
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.91.8.3403
更新日期:1994-04-12 00:00:00
abstract::The biosynthesis of the peroxisomal enzymes acyl-CoA oxidase, 3-oxoacyl-CoA thiolase (acetyl-CoA acyl-transferase, EC 2.3.1.16), and catalase (EC 1.11.1.6) was studied in cultured skin fibroblasts from a control subject and from patients with Zellweger syndrome and the infantile form of Refsum disease, inherited disor...
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.83.16.6156
更新日期:1986-08-01 00:00:00