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1.
Ana Rodríguez Takehiko Shimada Magdalena Cervera Ana Redondo Berta Alquézar María Jesús Rodrigo Lorenzo Zacarías Lluís Palou María M López Leandro Pe?a 《Plant signaling & behavior》2015,10(6)
Volatile organic compounds (VOCs) are secondary metabolites acting as a language for the communication of plants with the environment. In orange fruits, the monoterpene D-limonene accumulates at very high levels in oil glands from the peel. Drastic down-regulation of D-limonene synthase gene expression in the peel of transgenic oranges harboring a D-limonene synthase transgene in antisense (AS) configuration altered the monoterpene profile in oil glands, mainly resulting in reduced accumulation of D-limonene. This led to fruit resistance against Penicillium digitatum (Pd), Xanthomonas citri subsp. citri (Xcc) and other specialized pathogens. Here, we analyze resistance to pathogens in independent AS and empty vector (EV) lines, which have low, medium or high D-limonene concentrations and show that the level of resistance is inversely related to the accumulation of D-limonene in orange peels, thus explaining the need of high D-limonene accumulation in mature oranges in nature for the efficient attraction of specialized microorganism frugivores. 相似文献
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C. Lu F.G. Acién Fernández E. Cañizares Guerrero D.O. Hall E. Molina Grima 《Journal of applied phycology》2002,14(5):331-342
The outdoor production of Monodus subterraneus wasstudied in bubble column and helical reactors, mainly analysing the influenceofdilution rate, air flow rate and solar irradiance on growth rate andbiochemicalcomposition. Photoinhibition and photo-oxidation phenomena were also analysed.The cultures were stressed at high solar irradiance and dissolved oxygenconcentrations. A clear relationship between stress of the cultures and thefluorescence from PSII measurements was observed, the Fv/Fm ratio being lowerinthe helical reactor than in the bubble column. Growth rate and biomassproductivity were both a function of the average irradiance and the Fv/Fmratio;maximum values of 0.040 h–1 and 0.54 gL–1 d–1 were measured. The influenceofphotoinhibition and average irradiance was modelled, the model also fitting theexperimental data reported by another author. The chlorophyll contenthyperbolically decreased, whereas the carotenoid content decreased linearlywiththe average irradiance. The higher the dilution rate the higher the protein andcarbohydrate content of the biomass, and the lower the lipid content. Theeicosapentaenoic acid (EPA) content ranged from 2.3 to 3.2% d.wt, the higherthe dilution rate, the lower EPA content, although the higher the EPAproportion. Maximum EPA productivity was only 9 mg L–1d–1, due to the stress to which the cultures wereexposed. 相似文献
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In a pot experiment, burning or clipping ofTrifolium pratense plants colonized by the vesiculararbuscular mycorrhizal (VAM) fungusAcaulospora scrobiculata increased the number of spores in the substrate and the abundance of vesicles. The length of external mycelium and inoculum potential increased with clipping, but decreased with plant burning. Results suggest that the loss of photosynthesising tissue does not explain the effect of burning on VAM propagule activity. ei]R O D Dixon 相似文献
7.
Treatment of nonmucoid Pseudomonas aeruginosa with gyrase inhibitors such as ciprofloxacin, norfloxacin, and ofloxacin, which target the A subunit of topoisomerase II,
resulted in 100% conversion to the mucoid phenotype. However, antibiotics that partially inhibited growth and macromolecular
synthesis (DNA, RNA, protein, or peptidoglycan) of nonmucoid isolates in a gluconate-limited chemostat culture system did
not promote conversion to mucoid subpopulations. An increase in resistance was observed in populations that expressed the
mucoid phenotype. Both mucoid conversion and antibiotic resistance were completely reversible when ciprofloxacin pressure
was withdrawn, but only partially reversible by the removal of norfloxacin and ofloxacin. Thus, these experiments indicate
that in the presence of some fluoroquinolones, a conditional response resulting in mucoid conversion and antibiotic resistance
may occur.
Received: 28 January 1997 / Accepted: 12 February 1997 相似文献
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Evelyn Rodríguez-Estrada Mónica Fernández-Sánchez Jairo Muñoz-Delgado Ana Fresan-Orellana Gustavo Reyes-Terán 《Biological Rhythm Research》2016,47(1):1-6
The Steven–Johnson syndrome (SJS) is characterized by a sudden onset of mucous membrane erosion (predominantly oral mucosa, lips, and conjunctivae) with widespread blistering of the skin involving up to 10% of the body surface area. It is almost always a drug-related reaction, although it can be caused by infections and immunizations. A 33-year-old man with recent diagnosis of HIV infection developed antiretroviral treatment (ART)-associated SJS. Physical activity and sleep parameters were recorded by wrist actigraphy in four different consecutive scenarios: baseline assessment, first ART regimen, hospitalization, and second ART regimen. Significant differences were observed in physical activity patterns between the four phases. No differences in sleep parameters were found. To our knowledge, this is the first study recording physical activity changes and sleep during a SJS reaction. 相似文献