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1.
An Ustilago maydis ergosterol biosynthesis mutant (A14) which is partially blocked in sterol 14alpha-demethylase (P45014DM) activity is described. This mutant accumulated the abnormal 14alpha-methyl sterols, eburicol, 14alpha-methylfecosterol, and obtusifoliol, along with significant amounts of ergosterol. Although the A14 mutant grew nearly as well as the wild type, it was impaired in cell extension growth, which indicated a dysfunction in apical cell wall synthesis. The mutant was also found to be hypersensitive to the azole fungicides penconazole and tebuconazole. 相似文献
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Meno Laura Escuredo Olga Rodríguez-Flores Maria Shantal Seijo Maria Carmen 《Aerobiologia》2021,37(2):309-320
Aerobiologia - Potatoes production is the main source of income in A Limia (Northwest Spain). Most of the potatoes harvest is stored in piles in farmer´s warehouses without systems to control... 相似文献
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JA Kiernan 《Biotechnic & histochemistry》2013,88(5-6):203-210
Hexazonium pararosaniline is a valuable reagent that has been used in enzyme activity histochemistry for 50 years. It is an aqueous solution containing the tris-diazonium ion derived from pararosaniline, an aminotriarylmethane dye, and it contains an excess of nitrous acid that was not consumed in the diazotization reaction. Other investigators have found that immersion for 2 min in an acidic (pH 3.5) 0.0015 M hexazonium pararosaniline solution can protect cryostat sections of unfixed animal tissues from the deleterious effects of aqueous reagents such as buffered solutions used in immunohistochemistry, while preserving specific affinities for antibodies. In the present investigation hexazonium pararosaniline protected lymphoid tissue and striated muscle against the damaging effects of water or saline. The same protection was conferred on unfixed sections treated with dilute nitrous or hydrochloric acid in concentrations similar to those in hexazonium pararosaniline solutions. Model tissues (solutions, gels or films containing gelatin and/or bovine albumin) responded predictably to well known cross-linking (formaldehyde) or coagulant (mercuric chloride) fixatives. Hexazonium pararosaniline solutions prevented the dissolution of protein gels in water only after 9 or more days of contact, during which time considerable swelling occurred. It is concluded that there is no evidence for a “fixative” action of hexazonium pararosaniline. The protective effect on frozen sections of unfixed tissue is attributable probably to the low pH of the solution. 相似文献
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Juan P. de-Torres David Blanco Ana B. Alcaide Luis M. Seijo Gorka Bastarrika María José Pajares Arrate Mu?oz-Barrutia Carlos Ortiz-de-Solorzano Ruben Pio Arantza Campo Usua Montes Victor Segura Jesús Pueyo Luis M. Montuenga Javier J. Zulueta 《PloS one》2013,8(4)
Rationale
Low-grade inflammation and emphysema have been shown to be associated with an increased risk of lung cancer. However, the systemic inflammatory response in patients with emphysema is still unknown.Objective
To compare the plasma cytokine profiles in two groups of current or former smokers without airway obstruction: a control group of individuals without computed tomography (CT) detected emphysema vs. a study group of individuals with CT detected emphysema.Methods
Subjects underwent a chest CT, spirometry, and determination of EGF, IL-15, IL-1ra, IL-8, MCP-1, MIP-1β, TGFα, TNFα, and VEGF levels in plasma. Cytokine levels in each group were compared adjusting for confounding factors.Results
160 current smokers and former smokers without airway obstruction participated in the study: 80 without emphysema and 80 subjects with emphysema. Adjusted group comparisons revealed significant reductions in EGF (−0.317, p = 0.01), IL-15 (−0.21, p = 0.01), IL-8 (−0.180, p = 0.02) and IL-1ra (−0.220, p = 0.03) in subjects with emphysema and normal spirometry.Conclusions
Current or former smokers expressing a well-defined disease characteristic such as emphysema, has a specific plasma cytokine profile. This includes a decrease of cytokines mainly implicated in activation of apoptosis or decrease of immunosurveillance. This information should be taken into account when evaluated patients with tobacco respiratory diseases. 相似文献7.
Francisco Cuesta Carolina Tovar Luis D. Llambí William D. Gosling Stephan Halloy Julieta Carilla Priscilla Muriel Rosa I. Meneses Stephan Beck Carmen Ulloa Ulloa Karina Yager Nikolay Aguirre Paul Viñas Jorge Jácome David Suárez-Duque Wouter Buytaert Harald Pauli 《Journal of Biogeography》2020,47(2):408-420
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Fifty-four honey samples collected over two consecutive harvest seasons (2009–2010) from different floristic areas of Romania were analysed. A melissopalynological analysis including qualitative and quantitative analyses was carried out in order to identify the principal pollen types in Romanian honeys and therefore, the important plants exploited by Apis mellifera in this country. Seventy-seven pollen types from 35 botanical families were identified. The main pollen forms were: Brassica napus-type, Tilia, Helianthus annuus, Robinia pseudoacacia, Prunus, Castanea sativa, Fragaria-type and Plantago-type. Honey samples were classified as: acacia honey (Robinia pseudoacacia), lime honey (Tilia), rape honey (Brassica napus-type), sunflower honey (Helianthus annuus), cherry honey (Prunus). Three of them were honeydew honeys whereas the others were all polyfloral. The results from this study can be used as a palynological baseline data of Romanian artisanal honeys. 相似文献
10.
Water hyacinth Eichhornia crassipes is considered the most damaging aquatic weed in the world. However, few studies have quantified the impact of this weed economically and ecologically, and even fewer studies have quantified the benefits of its control. This paper focuses on water loss saving as the benefit derived from biological control of this plant between 1990 and 2013 at New Year’s Dam, Alicedale, Eastern Cape, South Africa. Estimates of water loss due to evapotranspiration from water hyacinth vary significantly; therefore, the study used three different rates, high, medium and low. A conservative raw agriculture value of R 0.26 per m3 was used to calculate the benefits derived by the water saved. The present benefit and cost values were determined using 10% and 5% discount rates. The benefit/cost ratio at the low evapotranspiration rate was less than one, implying that biological control was not economically viable but, at the higher evapotranspiration rates, the return justified the costs of biological control. However, at the marginal value product of water, the inclusion of the costs of damage to infrastructure, or the adverse effects of water hyacinth on biodiversity, would justify the use of biological control, even at the low transpiration rate. 相似文献