Abstract:
:Most cells in the well-known pre-B-lymphocyte line 18-81 have correctly assembled genes for both alleles at the immunoglobulin heavy chain locus. Only one allele is "active"; the other, "silent" allele contains an amber termination codon. The rate of reversion of this amber codon was determined to be 0.3-1 X 10(-4) per cell generation. This high rate is termed hypermutation.
journal_name
Proc Natl Acad Sci U S Aauthors
Wabl M,Burrows PD,von Gabain A,Steinberg Cdoi
10.1073/pnas.82.2.479subject
Has Abstractpub_date
1985-01-01 00:00:00pages
479-82issue
2eissn
0027-8424issn
1091-6490journal_volume
82pub_type
杂志文章abstract::Reversible photoswitching of individual molecules has been demonstrated for a number of mutants of the green fluorescent protein (GFP). To date, however, a limited number of switching events with slow response to light have been achieved at the single-molecule level. Here, we report reversible photoswitching character...
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.0500489102
更新日期:2005-07-05 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.70.1.18
更新日期:1973-01-01 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.1203141109
更新日期:2012-07-10 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.88.12.5331
更新日期:1991-06-15 00:00:00
abstract::CD4-expressing T cells in lymphoid organs are infected by the primary strains of HIV and represent one of the main sources of virus replication. Gene therapy strategies are being developed that allow the transfer of exogenous genes into CD4(+) T lymphocytes whose expression might prevent viral infection or replication...
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.94.16.8640
更新日期:1997-08-05 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.94.21.11221
更新日期:1997-10-14 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.1712628115
更新日期:2018-07-17 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.91.17.8253
更新日期:1994-08-16 00:00:00
abstract::2-Deoxy-D-[14C]glucose autoradiography was used in awake rats to map neural activity in the sensorimotor sector of striatum. Stimulation of hindlimb, trunk, or forelimb activated primary sensory cortex in a localized columnar pattern, indicating activation of somatosensory receptors and a discrete cortical functional ...
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.89.16.7403
更新日期:1992-08-15 00:00:00
abstract::Natural ecosystems contain many individuals and species interacting with each other and with their abiotic environment. Such systems can be expected to exhibit complex dynamics in which small perturbations can be amplified to cause large changes. Here, we document the reorganization of an arid ecosystem that has occur...
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.94.18.9729
更新日期:1997-09-02 00:00:00
abstract::We have found the two-dimensional electrophoretic technique of O'Farrell to be highly efficient in the detection of charge-change substitutions in a large number of proteins. We have applied this method to determine the level of heterozygosity of the most abundant proteins in Drosophila melanogaster adults from a natu...
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.76.5.2381
更新日期:1979-05-01 00:00:00
abstract::Experimental systemic lupus erythematosus (SLE) can be induced in naive mice by immunization with a murine monoclonal anti-DNA antibody (mAb), 5G12, that bears a major idiotype designated 16/6 Id. Strain-dependent differences were observed in the proliferative responses of lymph node cells of mice immunized with two 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.94.9.4620
更新日期:1997-04-29 00:00:00
abstract::The human Melan-A/MART-1 gene encodes an HLA-A2-restricted peptide epitope recognized by melanoma-reactive CD8(+) cytotoxic T lymphocytes. Here we report that this gene also encodes at least one HLA-DR4-presented peptide recognized by CD4(+) T cells. The Melan-A/MART-1(51-73) peptide was able to induce the in vitro ex...
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.97.1.400
更新日期:2000-01-04 00:00:00
abstract::Clostridium ljungdahlii is an anaerobic homoacetogen, able to ferment sugars, other organic compounds, or CO(2)/H(2) and synthesis gas (CO/H(2)). The latter feature makes it an interesting microbe for the biotech industry, as important bulk chemicals and proteins can be produced at the expense of CO(2), thus combining...
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.1004716107
更新日期:2010-07-20 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
doi:10.1073/pnas.86.14.5666
更新日期:1989-07-01 00:00:00
abstract::The flux of solvent water coupled to the transit of ions through protein pores is considerable. The effect of this electroosmotic solvent flow on the binding of a neutral molecule [beta-cyclodextrin (betaCD)] to sites within the staphylococcal alpha-hemolysin pore was investigated. Mutant alpha-hemolysin pores were us...
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.2531778100
更新日期:2003-12-23 00:00:00
abstract::An effective vaccine that can protect against HIV infection does not exist. A major reason why a vaccine is not available is the high mutability of the virus, which enables it to evolve mutations that can evade human immune responses. This challenge is exacerbated by the ability of the virus to evolve compensatory mut...
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.2022496118
更新日期:2021-02-02 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: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
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更新日期:2003-12-23 00:00:00
abstract::Oil-in-water emulsions are potent human adjuvants used for effective pandemic influenza vaccines; however, their mechanism of action is still unknown. By combining microarray and immunofluorescence analysis, we monitored the effects of the adjuvants MF59 oil-in-water emulsion, CpG, and alum in the mouse muscle. MF59 i...
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.1232173100
更新日期:2003-06-10 00:00:00
abstract::To investigate the evolution of the mammalian sex chromosomes, we have compared the gene content of the X chromosomes in the mammalian groups most distantly related to man (marsupials and monotremes). Previous work established that genes on the long arm of the human X chromosome are conserved on the X chromosomes in a...
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.88.24.11256
更新日期:1991-12-15 00:00:00
abstract::In the presence of N(alpha),N(epsilon)-diacetyl-L-Lys-D-Ala-D-Ala as donor, and either D-[(14)C]alanine, [(14)C]-glycine, or meso-[(3)H]diaminopimelic acid as acceptor, the DD carboxypeptidases from Streptomyces R61 and R39 catalyze a transpeptidation reaction with the release of terminal D-alanine from the donor 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.69.3.662
更新日期:1972-03-01 00:00:00
abstract::The error frequency of in vitro DNA synthesis using a natural DNA template has been measured with a biological assay for nucleotide substitutions. phiX174 DNA containing an amber mutation was copied in vitro by Escherichia coli DNA polymerase I, and the reversion frequency of the progeny DNA was determined by transfec...
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.75.4.1924
更新日期:1978-04-01 00:00:00
abstract::Phagocytic cells are a critical line of defense against infection. The ability of a pathogen to survive and even replicate within phagocytic cells is a potent method of evading the defense mechanisms of the host. A number of pathogens survive within macrophages after phagocytosis and this contributes to their virulenc...
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.93.9.4197
更新日期:1996-04-30 00:00:00
abstract::Nanoparticle-based experimental therapeutics are currently being investigated in numerous human clinical trials. CALAA-01 is a targeted, polymer-based nanoparticle containing small interfering RNA (siRNA) and, to our knowledge, was the first RNA interference (RNAi)-based, experimental therapeutic to be administered to...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2014-08-05 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.85.16.5769
更新日期:1988-08-01 00:00:00
abstract::beta-Adrenergic receptors on Friend erythroleukemic cells were identified by the use of 125I-labeled hydroxybenzylpindolol, a potent beta-adrenergic antagonist. Binding of this ligand was saturable and stereospecific. The relative orders of potency of isoproterenol, epinephrine, and norepinephrine to displace bound hy...
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.77.7.4065
更新日期:1980-07-01 00:00:00
abstract::In the cytoplasm of well-spread cultured normal fibroblasts, actin is organized into a network of cables that run the length of the cell just inside the adherent cell membrane. A diffuse matrix replaces the cables in fibroblasts that have become tumorigenic as a result of oncogenic transformation. We have found a simi...
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.74.7.3019
更新日期:1977-07-01 00:00:00
abstract::Pure cultures of human breast epithelial cells and of fibroblastic cells in early passage provided the opportunity to ask whether either cell type had the capability for metabolizing chemical carcinogens and, if so, was the fate of the metabolic products compatible with chemical carcinogens being a factor in the initi...
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.78.10.6251
更新日期:1981-10-01 00:00:00