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Karsten R.O. Hazlett Kerry A. Cirillo 《Microbes and infection / Institut Pasteur》2009,11(10-11):828-834
Concerns over weaponizable bacteria have recently prompted considerable interest in Francisella tularensis (Ft). In addition to its potential illicit use, Ft occurs naturally in diverse ecological niches including mammals, arthropods, and fresh water protozoans. Here we review the current knowledge of Ft adaptation which has ramifications for both basic and applied research. 相似文献
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The stimulation of cyclic AMP and lipolysis by LY79771, a phenethanolamine antiobesity compound, and its 3 stereoisomers in adipose tissue of obese viable yellow mice and normal mice were studied. Both activities were stereo-specific with LY79771, the R,S isomer, and LY79730, the R,R isomer, being more potent than LY103085, the S,S isomer, and LY103672, the S,R isomer. Propranolol, a nonspecific β-antagonist, completely inhibited the elevation of cyclic AMP and lipolysis whereas atenolol, a specific β1 antagonist, inhibited the elevation of cyclic AMP but did not completely inhibit lipolysis. These findings indicate that the elevation of cyclic AMP was mediated by the β1- receptor whereas the stimulation of lipolysis was mediated by both the β1 and β2 receptors. The adipose tissue of the obese viable yellow mice responded to these compounds less than that of the normal mice. 相似文献
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In budding yeast, we have found that sister rDNA arrays marked with fluorescent probes can be visualized as two distinguishable
strands during metaphase. Upon anaphase, these arm loci are drawn into the spindle, where they adopt a cruciform-like structure
and stretch 2.5-fold as they migrate to the poles. Therefore, while sister rDNA arrays appear separated in metaphase, mechanical
linkages between sister arm loci persist throughout anaphase in yeast, as shown in grasshopper spermatocytes (Paliulis and
Nicklas 2004). These linkages are partially dependent on the protector of cohesin, SGO1. In anaphase, the spatially regulated dissolution
of these mechanical linkages serves to prevent premature sister separation and restrain the rate of spindle elongation. Thus,
sister separation is temporally controlled and linkages between sister chromatids contribute to the regulation of anaphase
spindle elongation.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Climate and anthropogenic factors determine site occupancy in Scotland's Northern‐range badger population: implications of context‐dependent responses under environmental change
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