Abstract:
:Mature larvae of Sarcophaga argyrostoma fail to form puparia when kept in contact with water, but pupariate after having been subsequently exposed to dryness for 30 hr. They become increasingly more sensitive to injected ecdysone the longer the exposure to dry conditions. A second wet treatment halts the production of hormone that had occurred during the dry period, and reduces a sensitization to injected ecdysone during the intervening dry treatment. Apparently, injected ecdysone had cumulative effects not with the endogenous or exogenous hormone, but with its covert effects which had arisen during the dry period and persisted throughout the second wet period. The hind parts of larvae ligated at the end of a wet period pupariate when injected with either one massive dose of ecdysone, or a far smaller total of several subsequent doses. In the case of two unequal doses, the effect was greater when the smaller dose was injected first. In order to get pupariation with minimal effective doses, a continuous supply of the hormone during a certain period is required. It is suggested that the inhibition of pupariation by moisture has arisen as an adaptation to unfavorable conditions.
journal_name
Proc Natl Acad Sci U S Aauthors
Zdarek J,Fraenkel Gdoi
10.1073/pnas.67.1.331subject
Has Abstractpub_date
1970-09-01 00:00:00pages
331-7issue
1eissn
0027-8424issn
1091-6490journal_volume
67pub_type
杂志文章abstract::Urbanization and rural-urban migration are two factors driving global patterns of disease and mortality. There is significant concern about their potential impact on disease burden and the effectiveness of current control approaches. Few attempts have been made to increase our understanding of the relationship between...
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.1712767115
更新日期:2018-05-01 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:1989-02-01 00:00:00
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doi:10.1073/pnas.0607874103
更新日期:2006-10-31 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:2011-08-16 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,评审
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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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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.0704191104
更新日期:2007-11-20 00:00:00
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更新日期:2006-03-14 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
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更新日期:2002-03-19 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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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.77.11.6606
更新日期:1980-11-01 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.97.18.10077
更新日期:2000-08-29 00:00:00
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pub_type: 临床试验,杂志文章
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更新日期:2013-03-26 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:2005-06-07 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:1983-11-01 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:2007-05-01 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:2008-08-12 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.80.16.5080
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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:1971-11-01 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:1978-04-01 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:2017-12-26 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
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更新日期:2014-09-09 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::The human beta-globin locus control region (LCR) consists of four erythroid-specific DNaseI hypersensitive sites (HSs) at the 5' end of the beta-globin cluster. The LCR functions over a long distance on chromosome 11 to regulate transcription and replication of the beta-globin genes. To determine whether the HSs funct...
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.94.9.4566
更新日期:1997-04-29 00:00:00
abstract::Apoptotic cells contain nuclear autoantigens that may initiate a systemic autoimmune response. To explore the mechanism of antibody binding to apoptotic cells, 3H9, a murine autoantibody with dual specificity for phospholipids and DNA, was used. H chain mutants of 3H9 were constructed, expressed as single-chain Fv (sc...
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.241510698
更新日期:2001-11-20 00:00:00