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Detection and genotyping of group A rotaviruses isolated from sewage samples in Monastir,Tunisia between April 2007 and April 2010 下载免费PDF全文
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Travis Park Felix G. Marx Erich M. G. Fitzgerald Alistair R. Evans 《Journal of morphology》2017,278(6):801-809
The pygmy right whale, Caperea marginata , is the least understood extant baleen whale (Cetacea, Mysticeti). Knowledge on its basic anatomy, ecology, and fossil record is limited, even though its singular position outside both balaenids (right whales) and balaenopteroids (rorquals + grey whales) gives Caperea a pivotal role in mysticete evolution. Recent investigations of the cetacean cochlea have provided new insights into sensory capabilities and phylogeny. Here, we extend this advance to Caperea by describing, for the first time, the inner ear of this enigmatic species. The cochlea is large and appears to be sensitive to low‐frequency sounds, but its hearing limit is relatively high. The presence of a well‐developed tympanal recess links Caperea with cetotheriids and balaenopteroids, rather than balaenids, contrary to the traditional morphological view of a close Caperea‐balaenid relationship. Nevertheless, a broader sample of the cetotheriid Herpetocetus demonstrates that the presence of a tympanal recess can be variable at the specific and possibly even the intraspecific level. 相似文献
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Jung Mi Lim Kyung S. Lee Hyun Ae Woo Dongmin Kang Sue Goo Rhee 《The Journal of cell biology》2015,210(1):935-945
Proteins associated with the centrosome play key roles in mitotic progression in mammalian cells. The activity of Cdk1-opposing phosphatases at the centrosome must be inhibited during early mitosis to prevent premature dephosphorylation of Cdh1—an activator of the ubiquitin ligase anaphase-promoting complex/cyclosome—and the consequent premature degradation of mitotic activators. In this paper, we show that reversible oxidative inactivation of centrosome-bound protein phosphatases such as Cdc14B by H2O2 is likely responsible for this inhibition. The intracellular concentration of H2O2 increases as the cell cycle progresses. Whereas the centrosome is shielded from H2O2 through its association with the H2O2-eliminating enzyme peroxiredoxin I (PrxI) during interphase, the centrosome-associated PrxI is selectively inactivated through phosphorylation by Cdk1 during early mitosis, thereby exposing the centrosome to H2O2 and facilitating inactivation of centrosome-bound phosphatases. Dephosphorylation of PrxI by okadaic acid–sensitive phosphatases during late mitosis again shields the centrosome from H2O2 and thereby allows the reactivation of Cdk1-opposing phosphatases at the organelle. 相似文献
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