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1. The responsiveness of adenylate cyclase and enzyme secretin for secretin and the C-terminal octapeptide of pancreozymin has been investigated in particulate fractions of the pancreas of five different species. 2. The adenylate cyclase is sensitive to the C-terminal octapeptide of pancreozymin in all species investigated. 3. The enzyme is much more sensitive to secretin in rat and cat than in mouse and rabbit, whereas with guinea pig intermediate values are obtained. 4. The enzyme secretion is stimulated by secretin in pancreatic fragments of rat and cat, but not in those of mouse and rabbit. 5. These results suggest that in species where secretin stimulated enzyme secretion, it does so by stimulating the adenylate cyclase system. 相似文献
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The product of hydrolysis of the active principle of the herbicide Bidisine® is degraded in at least two different ways. One way gives p-chlorobenzoic acid. The other, more important one, gives a conjugate with l-cysteine, which is further oxidized. The ability to oxidize the conjugate provided a means of distinguishing between susceptible and resistant plant species. 相似文献
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James D. Glover Lorna Taylor Adrian Sherman Caroline Zeiger-Poli Helen M. Sang Michael J. McGrew 《PloS one》2013,8(11)
In this work, we describe a single piggyBac transposon system containing both a tet-activator and a doxycycline-inducible expression cassette. We demonstrate that a gene product can be conditionally expressed from the integrated transposon and a second gene can be simultaneously targeted by a short hairpin RNA contained within the transposon, both in vivo and in mammalian and avian cell lines. We applied this system to stably modify chicken primordial germ cell (PGC) lines in vitro and induce a reporter gene at specific developmental stages after injection of the transposon-modified germ cells into chicken embryos. We used this vector to express a constitutively-active AKT molecule during PGC migration to the forming gonad. We found that PGC migration was retarded and cells could not colonise the forming gonad. Correct levels of AKT activation are thus essential for germ cell migration during early embryonic development. 相似文献
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Jan Klimaszewski Reginald P. Webster David W. Langor Caroline Bourdon H.E. James Hammond Greg R. Pohl Benoit Godin 《ZooKeys》2014,(412):9-40
Four species of Gnathusa Fenyes (G. alfacaribou Klimaszewski & Langor, G. caribou Lohse, G. eva Fenyes, and G. tenuicornis Fenyes) occur in the Nearctic and in Canada. Three species of Ocyusa Kraatz (O. asperula Casey, O. californica Bernhauer, O. canadensis Lohse), and three species of Mniusa Mulsant and Ray (M. minutissima (Klimaszewski & Langor), M. yukonensis (Klimaszewski & Godin), and M. odelli Klimaszewski & Webster, sp. n.), are known from the Nearctic and all but O. californica occur in Canada. The recently described Gnathusa minutissima Klimaszewski and Langor and Ocyusa yukonensis Klimaszewski and Godin, are transferred here to the genus Mniusa Mulsant & Rey. New provincial and state records are reported for: G. eva (Alberta), G. tenuicornis (Alberta, Oregon, and New Brunswick), O. canadensis (New Brunswick and Newfoundland), M. minutissima (New Brunswick), and M. yukonensis (Nova Scotia, New Brunswick, Quebec, and British Columbia). The female of M. yukonensis was discovered and is illustrated for the first time. The genus Mniusa is reported for the first time from Canada and represents the first confirmed generic record for North America. Keys for identification of all Canadian species, images of body and genital structures, maps showing distribution mainly in Canada, and new bionomics data are provided. 相似文献
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