Abstract:
:The circular dichroism data on 17 adenine nucleosides show that the 260- and 207-mmu absorption systems of the adenine chromophore each contain at least two electronic transitions. The CD maxima are commonly found at around 260, 220, and 200 mmu, and occasionally at 240 mmu. Solvent studies suggest that these CD bands arise from pi-pi(*) transitions. A weak absorption band that obeys the McConnell criteria of an n-pi(*) band is resolved at about 290 mmu in hydrocarbon solvents. This band exhibits very little rotatory power.
journal_name
Proc Natl Acad Sci U S Aauthors
Miles DW,Robins MJ,Robins RK,Eyring Hdoi
10.1073/pnas.62.1.22subject
Has Abstractpub_date
1969-01-01 00:00:00pages
22-9issue
1eissn
0027-8424issn
1091-6490journal_volume
62pub_type
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.80.11.3188
更新日期:1983-06-01 00:00:00
abstract::Through rapid genetic adaptation and natural selection, the Plasmodium falciparum parasite--the deadliest of those that cause malaria--is able to develop resistance to antimalarial drugs, thwarting present efforts to control it. Genome-wide association studies (GWAS) provide a critical hypothesis-generating tool for u...
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:2013-07-23 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:2018-07-31 00:00:00
abstract::Mature immunologically competent dendritic cells are the most efficient antigen-presenting cells that powerfully activate T cells and initiate and sustain immune responses. Indeed, dendritic cells are able to efficiently capture antigens, express high levels of costimulatory molecules, and produce the combination of c...
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.190204697
更新日期:2000-09-26 00:00:00
abstract::Recent advances in cell-free expression protocols have opened a new avenue toward high-resolution structural investigations of membrane proteins by x-ray crystallography and NMR spectroscopy. One of the biggest challenges for liquid-state NMR-based structural investigations of membrane proteins is the significant peak...
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abstract::To investigate the molecular basis for the tissue-specific expression of the human CD2 gene, its chromatin configuration was assessed by determining DNase I hypersensitivity and the degree of methylation during T-cell lineage commitment and development. Tissue-specific DNase I-hypersensitive sites were found within th...
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: 历史文章,杂志文章
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更新日期:2011-04-05 00:00:00
abstract::Optical imaging of individual vesicle exocytosis is providing new insights into the mechanism and regulation of secretion by cells. To study calcium-triggered secretion from astrocytes, we used acridine orange (AO) to label vesicles. Although AO is often used for imaging exocytosis, we found that imaging vesicles labe...
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:2007-08-28 00:00:00
abstract::A sensitive in vitro crosslinking technique using a photoactive derivative of the chimeric activator LexA-E2F-1 was used to identify yeast proteins that might influence the response of RNA polymerase II to transcriptional activators. We found that a novel yeast protein, Xtc1p, could be covalently crosslinked to the ac...
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.95.19.11122
更新日期:1998-09-15 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.80.14.4499
更新日期:1983-07-01 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
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更新日期:2010-12-28 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:1970-11-01 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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更新日期:2014-05-20 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:1985-02-01 00:00:00
abstract::We describe here the 1.7-A resolution structure of a single-chain antibody variable domain (scFv) molecule, based on the carbohydrate-binding antibody Se155-4, complexed with the trisaccharide ligand alpha-D-Gal(1-->2)[alpha-D-Abe(1-->3)]alpha-D-Manp1-->OMe, where Abe is abequose. The scFv expressed in Escherichia col...
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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:2020-01-07 00:00:00
abstract::The spectrum of cellular targets in the autoimmune diseases is both large and varied and includes among the nuclear components the so-called Sm and RNP antigens associated with systemic lupus erythematosus. The use of immunoaffinity chromatography with dual specificity for the Sm and RNP antigens has allowed for their...
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:1981-01-01 00:00:00
abstract::We have tested the effect of increased ribosomal fidelity on a modified version of the programmed release factor 2 (RF2) translational frameshift. In the constructs tested, the original UGA codon at the site of the shift was replaced by either of two sense codons, UGG (tryptophan), which allows a frameshift of approxi...
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更新日期:1987-03-01 00:00:00
abstract::Mutants of Arabidopsis that contain reduced levels of polyunsaturated fatty acids showed growth characteristics at 22 degrees C that were very similar to wild type. By contrast, at 12 degrees C, the mutants failed to undergo stem elongation during reproductive growth although they produced normal flowers and fertile s...
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:1993-07-01 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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更新日期:2010-12-14 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:2014-12-09 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:2007-02-27 00:00:00
abstract::Chronic administration of the atypical antipsychotic drug, clozapine, to rodents has been shown to increase the concentration of apolipoprotein D (apoD) in several area of the brain, suggesting that apoD could be involved in the therapeutic effects of antipsychotic drugs and/or the pathology of psychotic illnesses. He...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2001-03-27 00:00:00