Abstract:
:The mode of action of "allogeneic supernatant" (the culture supernatant of a 24-hr mixedlymphocyte reaction), has been studied. This factor stimulates the response of spleen cell cultures depleted in thymus-derived lymphoid cells (T-cells) to antigens that elicit a thymus-dependent response. We used a limiting dilution analysis, in which the frequency and size of response of individual bone-marrow-derived lymphoid cells (B-cells) could be measured. In confirmation of other reports, the occurrence of B-cells responding to antigen under different conditions was shown to follow a Poisson distribution in mouse spleen cell suspensions. Allogeneic supernatant increased responses to thymus-dependent antigens, both by increasing the frequency of B-cells whose response is initiated and by increasing the numbers of antibody-forming cells obtained from each responding B-cell. Two fractions were obtained by dialysis of the supernatant. The nondialyzable fraction contained factors able to increase both the frequency of B-cells responding to sheep erythrocytes, and the size of the responding unit. The dialysate contained factors that were only able to increase the numbers of antibody-forming cells obtained per responding B-cell from B-cells whose response had already been initiated by antigen-specific T-cells. Since the nondialyzable factors were active in the absence of detectable functional T-cells, it was concluded that these factors, produced by T-cells, might represent one mechanism whereby T-cells cooperate with B-cells in the initiation or development of a humoral immune response.
journal_name
Proc Natl Acad Sci U S Aauthors
Hunter P,Kettman JRdoi
10.1073/pnas.71.2.512subject
Has Abstractpub_date
1974-02-01 00:00:00pages
512-6issue
2eissn
0027-8424issn
1091-6490journal_volume
71pub_type
杂志文章abstract::The chemosmotic model provides a framework for visualizing energy-coupled reactions (vectorial reaction sequences, membrane-dependent gradient formation, and charge separation of reacting species) and a mechanism for energy coupling (indirect coupling between the driving and driven reaction sequences mediated by a mem...
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.78.4.2240
更新日期:1981-04-01 00:00:00
abstract::The survival of motor neurons is controlled by multiple factors that regulate different aspects of their physiology. The identification of these factors is important because of their relationship to motor neuron disease. We investigate here whether Mullerian Inhibiting Substance (MIS) is a motor neuron survival factor...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.0508304102
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abstract::The autoimmune dermatologic disease pemphigus vulgaris (PV) is associated with the HLA serotypes DR4 and DRw6. Susceptibility to PV could be conferred either by sequences shared between the DR4 and DRw6 haplotypes or by different sequences in these haplotypes. We have examined the distribution of DR and DQ beta-chain ...
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.85.10.3504
更新日期:1988-05-01 00:00:00
abstract::The DNA sequences of wheat Acc-1 and Acc-2 loci, encoding the plastid and cytosolic forms of the enzyme acetyl-CoA carboxylase, were analyzed with a view to understanding the evolution of these genes and the origin of the three genomes in modern hexaploid wheat. Acc-1 and Acc-2 loci from each of the wheats Triticum ur...
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.0803981105
更新日期:2008-07-15 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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doi:10.1073/pnas.64.3.1103
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abstract::Several gene fusions have been constructed in which coding sequences for antigenic regions of the pre-S sequences of hepatitis B virus, hepatitis B surface antigen, and the envelope protein of human immunodeficiency virus were linked to the 3' end of that for the first 144 residues of hepatitis B core antigen. The seq...
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.86.16.6283
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::The L-A double-stranded RNA virus of Saccharomyces cerevisiae makes a gag-pol fusion protein by a -1 ribosomal frameshift. The pol amino acid sequence includes consensus patterns typical of the RNA-dependent RNA polymerases (EC 2.7.7.48) of (+) strand and double-stranded RNA viruses of animals and plants. We have carr...
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
doi:10.1073/pnas.1321640111
更新日期:2014-08-12 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.92.17.8074
更新日期:1995-08-15 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
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更新日期:1986-12-01 00:00:00
abstract::Among the 15 extracellular domains of the mannose 6-phosphate/insulin-like growth factor-2 receptor (M6P/IGF2R), domain 11 has evolved a binding site for IGF2 to negatively regulate ligand bioavailability and mammalian growth. Despite the highly evolved structural loops of the IGF2:domain 11 binding site, affinity-enh...
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.1513023113
更新日期:2016-05-17 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.86.7.2253
更新日期:1989-04-01 00:00:00
abstract::Cell-specific activation of the transcription factor sigma F during sporulation in Bacillus subtilis is controlled by a regulatory pathway involving the proteins SpoIIE, SpoIIAA, and SpoIIAB. SpoIIAB is an antagonist of sigma F, and SpoIIAA, which is capable of overcoming SpoIIAB-mediated inhibition of sigma F, is an ...
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.93.8.3238
更新日期:1996-04-16 00:00:00
abstract::The mechanism of phosphosylation and dephosphorylation of spectrin from human erythrocyte membranes has been examined under closely physiological conditions. The results support the hypothesis that spectrin is an autophosphorylating and dephosphorylating system. (i) Extraction from ghosts of up to 85% of the kinase (c...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.77.6.3264
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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:1982-11-01 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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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:1995-05-23 00:00:00
abstract::Ubiquitin C-terminal hydrolase-L1 (UCHL1), a neuron-specific de-ubiquitinating enzyme, is one of the most abundant proteins in the brain. We describe three siblings from a consanguineous union with a previously unreported early-onset progressive neurodegenerative syndrome featuring childhood onset blindness, cerebella...
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:2013-02-26 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.1717720115
更新日期:2018-10-23 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
doi:10.1073/pnas.0402784101
更新日期:2004-07-06 00:00:00
abstract::Classical studies suggest that high-level cognitive decisions (e.g., choosing between financial options) are suboptimal. In contrast, low-level decisions (e.g., choosing where to put your feet on a rocky ridge) appear near-optimal: the perception-cognition gap. Moreover, in classical tasks, people appear to put too mu...
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.1300239110
更新日期:2013-10-01 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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更新日期:2015-06-09 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
doi:10.1073/pnas.1721181115
更新日期:2018-05-15 00:00:00
abstract::The interaction of configurations, including all possible singly excited configurations, is incorporated into the calculation of oscillatory and rotatory intensities of simple nonplanar pi-electronic systems such as skewed butadiene and acrolein. The results are discussed in terms of the reliability of the (self-consi...
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.67.4.1727
更新日期:1970-12-01 00:00:00
abstract::A pH-dependent transition between delocalized and trapped mixed valence states of an engineered CuA center in azurin has been investigated by UV-visible absorption and electron paramagnetic resonance spectroscopic techniques. At pH 7.0, the CuA azurin displays a typical delocalized mixed valence dinuclear [Cu(1.5).......
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.0403473101
更新日期:2004-08-31 00:00:00
abstract::Stat3 protein has an important role in oncogenesis and is a promising anticancer target. Indirubin, the active component of a traditional Chinese herbal medicine, has been shown previously to inhibit cyclin-dependent kinases, resulting in cell cycle arrest. Here, we show that the indirubin derivatives E564, E728, 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.0409467102
更新日期:2005-04-26 00:00:00