Abstract:
:Glucagon and insulin are first detectable at the onset of rat pancreas organogenesis. Initially, the specific activity of glucagon is approximately 100-fold higher than that of insulin. At this early stage, endocrine storage granules, similar to alpha granules, are identifiable in electron micrographs. The granule characteristics, as well as the relative hormone levels, suggest that the early population of differentiated endocrine cells is in fact composed of glucagon-producing (A) cells. This high level of glucagon is present in the embryo much earlier than the metabolic processes thought to be controlled by this hormone. Moreover, glucagon-producing cells may be the first endocrine cells to differentiate. Other known endocrine products accumulate later, during the terminal stages of organogenesis. These observations suggest that glucagon may have a regulatory function in early embryogenesis.
journal_name
Proc Natl Acad Sci U S Aauthors
Rall LB,Pictet RL,Williams RH,Rutter WJdoi
10.1073/pnas.70.12.3478subject
Has Abstractpub_date
1973-12-01 00:00:00pages
3478-82issue
12eissn
0027-8424issn
1091-6490journal_volume
70pub_type
杂志文章abstract::Sex determination in mammals is governed by antagonistic interactions of two genetic pathways, imbalance in which may lead to disorders/differences of sex development (DSD) in human. Among 46,XX individuals with testicular DSD (TDSD) or ovotesticular DSD (OTDSD), testicular tissue is present in the gonad. Although the...
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:2020-06-16 00:00:00
abstract::A mechanistic understanding of the controls on carbon storage and losses is essential for our capacity to predict and mitigate human impacts on the global carbon cycle. Plant litter decomposition is an important first step for carbon and nutrient turnover, and litter inputs and losses are essential in determining soil...
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.1516157113
更新日期:2016-04-19 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:1997-08-19 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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更新日期:2019-11-05 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 临床试验,杂志文章
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更新日期:1995-08-01 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:1999-05-25 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:2013-12-10 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
pub_type: 杂志文章
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更新日期:1995-12-05 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:2005-11-15 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:1989-06-01 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:2007-10-16 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.1716252115
更新日期:2018-09-25 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:2012-12-18 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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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2011-05-24 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:2004-08-17 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
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更新日期:2003-02-18 00:00:00