Abstract:
:Normal as well as Rous sarcoma virus-infected chicken pectoral and chicken embryo fibroblasts proliferate actively in a plasma containing medium of physiological ion concentrations (Ca2+, 1.2 mM; Mg2+, 0.7 mM). Reduction of medium calcium and magnesium concentrations is necessary to achieve selective quiescence of normal fibroblasts in these cell systems. By contrast, normal chicken heart mesenchymal cells proliferate only sluggishly (one doubling or less during a 6-day period) in a plasma containing medium of physiologic ion concentrations, whereas Rous sarcoma virus-infected heart mesenchymal cells proliferate actively (more than four doublings during an initial 2-day phase of exponential growth). The chicken heart mesenchymal cell system therefore has great potential for studies of the mechanism that initiates cell replication and of the failure in cellular regulatory processes that is responsible for the autonomous initiation of replication of neoplastic cells. From comparison of the chicken heart mesenchymal cell system to dialyzed plasma-based systems in which 3T3 cells tend to proliferative quiescence, it is argued that this proliferative quiescence of 3T3 cells is a result of cell starvation and is not physiologically meaningful.
journal_name
Proc Natl Acad Sci U S Aauthors
Balk SDdoi
10.1073/pnas.77.11.6606subject
Has Abstractpub_date
1980-11-01 00:00:00pages
6606-10issue
11eissn
0027-8424issn
1091-6490journal_volume
77pub_type
杂志文章abstract::The location of renin (EC 3.4.99.19) in rat pituitary was determined by the peroxidase-antiperoxidase immunohistochemical technique. By using antisera prepared with purified rat renal renin, an immunoreactive substance was localized within ovoid cells scattered throughout the anterior pituitary. These cells were shown...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.78.12.7579
更新日期:1981-12-01 00:00:00
abstract::Fuchs endothelial corneal dystrophy (FECD) is a leading cause of corneal endothelial (CE) degeneration resulting in impaired visual acuity. It is a genetically complex and age-related disorder, with higher incidence in females. In this study, we established a nongenetic FECD animal model based on the physiologic outco...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2007-02-13 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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更新日期:2001-02-27 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:2012-07-10 00:00:00
abstract::The induction of antigen-specific tolerance is critical for the prevention of autoimmunity and maintenance of immune tolerance. In addition to their classical role as sentinels of the immune response-inducing T cell reactivity, dendritic cells (DCs) play an important role in maintaining peripheral tolerance through th...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2005-09-20 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:1982-05-01 00:00:00
abstract::Spectral methods are of fundamental importance in statistics and machine learning, because they underlie algorithms from classical principal components analysis to more recent approaches that exploit manifold structure. In most cases, the core technical problem can be reduced to computing a low-rank approximation to a...
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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更新日期:2004-08-24 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:1986-07-01 00:00:00
abstract::By exploiting the ability of Pseudomonas aeruginosa to infect a variety of vertebrate and nonvertebrate hosts, we have developed model systems that use plants and nematodes as adjuncts to mammalian models to help elucidate the molecular basis of P. aeruginosa pathogenesis. Our studies reveal a remarkable degree of con...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2000-08-01 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:1987-10-01 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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abstract::IL-17-producing CD27(-) γδ cells (γδ(27-) cells) are widely viewed as innate immune cells that make critical contributions to host protection and autoimmunity. However, factors that promote them over IFN-γ-producing γδ(27+) cells are poorly elucidated. Moreover, although human IL-17-producing γδ cells are commonly imp...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2012-10-23 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:2018-01-16 00:00:00
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更新日期:2002-06-25 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:2002-03-19 00:00:00
abstract::The use of matching variable number of tandem repeat (VNTR) profiles to link suspects with crimes is potentially very powerful, but it has been quite controversial. Initial debate over laboratory procedures has largely given way to debate over the statistical and population genetic issues involved in calculating the f...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,评审
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更新日期:1992-12-15 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:2019-03-05 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:1972-07-01 00:00:00
abstract::The six individual catalytic polypeptide chains within the two catalytic trimers of Escherichia coli aspartate transcarbamoylase (ATCase; EC 2.1.3.2) are folded into two discrete structural domains interconnected in part by helix 12, which comprises residues 285-305 and is located near the carboxyl terminus of the cha...
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.88.2.458
更新日期:1991-01-15 00:00:00
abstract::Expression of amino acid biosynthesis genes in bacteria is often repressed when abundant supplies of the cognate amino acid are available. Repression of the Bacillus subtilis lysC gene by lysine was previously shown to occur at the level of premature termination of transcription. In this study we show that lysine dire...
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.2133705100
更新日期:2003-10-14 00:00:00
abstract::Transplantation of pancreatic islets for treating type 1 diabetes is restricted to patients with critical metabolic lability resulting from the need for immunosuppression and the shortage of donor organs. To overcome these barriers, we developed a strategy to macroencapsulate islets from different sources that allow 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.1708420114
更新日期:2017-10-31 00:00:00