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41.
Three new antibiotically active metabolites were isolated from cultures of the fungus Pleurotellus hypnophilus. The structures which are closely related to the coriolins were elucidated by spectroscopic methods. Hypnophilin (1) has a hirsutane sceleton whereas pleurotellol (2) and pleurotellic acid (3) are sesquiterpenoids with novel hirsutane skeletons. The common structural feature of all three metabolites is an -methylene ketone moiety. The antibiotics inhibited the growth of several bacteria as well as of some fungi. In cells of the ascitic form of Ehrlich carcinoma RNA and DNA syntheses were more affected than protein synthesis. The mode of action was compared with the antimicrobial and cytotoxic effects of complicatic acid (4) and other -methylene ketones and lactones from higher plants. All the compounds tested reacted rapidly with cysteine to form adducts which were almost devoid of biological activity.Abbreviations ECA-cells Ehrlich carcinoma ascitic cells - MIC Minimal inhibitory concentration - MNNG N-methyl-N-nitro-N-nitrosoguanidine Antibiotics from Basidiomycetes. XIII. T. Anke, W. H. Watson, B. M. Giannetti, and W. Steglich: The alliacols A and B from Marasmius alliaceus (Jacq. ex Fr.) Fr. J. Antibiotics, submitted  相似文献   
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This research investigates how the impact of persuasive messages in the political domain can be improved when fit is created by subliminally priming recipients’ regulatory focus (either promotion or prevention) and by linguistic framing of the message (either strategic approach framing or strategic avoidance framing). Results of two studies show that regulatory fit: a) increases the impact of a political message favoring nuclear energy on implicit attitudes of the target audience (Study 1); and b) induces a more positive evaluation of, and intentions to vote for, the political candidate who is delivering a message concerning immigration policies (Study 2).  相似文献   
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Exogenous soluble human alpha3 noncollagenous (NC1) domain of collagen IV inhibits angiogenesis and tumor growth. These biological functions are attributed to the binding of alpha3NC1 to integrin alphavbeta3. However, in some tumor cells that express integrin alphavbeta3, the alpha3NC1 domain does not inhibit proliferation, suggesting that integrin alphavbeta3 expression is not sufficient to mediate the anti-tumorigenic activity of this domain. Therefore, in the present study, we searched for novel binding receptors for the soluble alpha3NC1 domain in cells lacking alphavbeta3 integrin. In these cells, soluble alpha3NC1 bound integrin alpha3beta1; however, unlike alphavbeta3, alpha3beta1 integrin did not mediate cell adhesion to immobilized alpha3NC1 domain. Interestingly, in cells lacking integrin alpha3beta1, adhesion to the alpha3NC1 domain was enhanced due to activation of integrin alphavbeta3. These findings indicate that integrin alpha3beta1 is a receptor for the alpha3NC1 domain and transdominantly inhibits integrin alphavbeta3 activation. Thus integrin alpha3beta1, in conjunction with integrin alphavbeta3, modulates cellular responses to the alpha3NC1 domain, which may be pivotal in the mechanism underpinning its anti-angiogenic and anti-tumorigenic activities.  相似文献   
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PFGE has been extensively used to obtain a reliable intra-species differentiation, although this technique has not been completely standardized. In this study, PFGE was applied to analyze in detail the patterns of 19 lesional S. aureus strains isolated from patients with impetigo, compared with 15 non-lesional strains isolated from nasal or pharyngeal swabs of the same patients. The strain DNA was extracted and processed as previously reported, using the strictest protocol to limit the variations between different analytical sets. To obtain maximum sensitivity and comparability, the electrophoresis patterns were analyzed by an automated and computerized reader (GelDoc1000). The DNA fragments (range 12-15 bands) obtained for each individual strain were then divided into 39 zones including from 1 to 4 bands for a total of at least 91 possible different gel positions. The positivity for each zone (and/or the positivity for the individual bands contained) was associated with the lesional/non-lesional origin and with the face localization of the strains.  相似文献   
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The chestnut gall wasp Dryocosmus kuriphilus is a global pest of chestnut (Castanea spp). Established as a pest in the mid-twentieth century in Japan, Korea and North America, this species was first reported in Europe in 2002. Following the successful release of a biological control agent Torymus sinensis in Japan, this parasitoid species has been released in Italy since 2005. Here we discuss the potential of T. sinensis as a viable management option for the biological control of D. kuriphilus in central Europe. We suggest that more consideration should be given to determining, (i) the conditions under which T. sinensis may attack alternative native gall wasp hosts and (ii) the likelihood of hybridization of this species with native Torymus. Both issues are central to predicting unassisted range expansion by released T. sinensis, and to assess the environmental risks associated with a more widespread release of this species in Europe.  相似文献   
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