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51.
M. CALZOLARI P. BONILAURI R. BELLINI S. BECKER M. DOTTORI 《Medical and veterinary entomology》2016,30(4):435-438
The Culex pipiens complex includes species with reported differences in vector competence for arthropod‐borne viruses, many of which are of significant importance to human health such as the West Nile virus and the Sindbis virus. This group of mosquitoes is difficult to distinguish morphologically; particularly as adult females. In Europe, the two species of the complex, Culex pipiens Linnaeus 1758 and Culex torrentium Martini 1925, are often found sympatrically. With the aim to characterize the presence and spread of both species in the Emilia‐Romagna region, Northern Italy, mosquitoes of the complex – collected during the West Nile virus surveillance plans – were tested by multiplex real‐time PCR for the detection of the two species Cx. pipiens and Cx. torrentium. A total of 24 165 mosquitoes, collected between 2012 and 2014 from 105 sites, and sorted in 204 pools, were tested. All tested pools were found to be composed of Cx. pipiens, whereas Cx. torrentium was not detected. These results indicate a likely absence of Cx. torrentium mosquitoes within the surveyed territory, whereas Cx. pipiens is widely distributed in the area mentioned. This is in line with previous reports, which describe a pre‐alpine distribution of Cx. torrentium in Italy. 相似文献
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VITOR O. BECKER 《Systematic Entomology》1984,9(3):245-280
ABSTRACT .
The type-material of Neotropical Gelechioidea described by Cajetan Felder and Alois F. Rogenhofer, involving forty specific names, is treated and its taxonomic placement discussed. Forty-four lectotype designations, thirty-four new combinations and twenty-seven new synonyms are established and one species is removed from synonymy. Illustrations of adults and genitalia are given for species of which material is available. 相似文献
The type-material of Neotropical Gelechioidea described by Cajetan Felder and Alois F. Rogenhofer, involving forty specific names, is treated and its taxonomic placement discussed. Forty-four lectotype designations, thirty-four new combinations and twenty-seven new synonyms are established and one species is removed from synonymy. Illustrations of adults and genitalia are given for species of which material is available. 相似文献
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BIELEFELD ULRICH; KORTJE KARL HEINZ; RAHMANN HINRICH; BECKER WILHELM 《Journal of Molluscan Studies》1993,59(3):323-338
In the freshwater snail Biomphalaria glabrata, the outer mantleepithelium and the transitional epithelium from the outer mantleepithelium to the belt are characterized by apical vesiclesof different electron density and vacuoles including lipid dropletsand fibrillar structures. Wide intercellular spaces predominatein the transitional epithelium. In addition to belt desmosomes,freeze fracture studies detect septate junctions as apical intercellularjunctions. The permeability of the septate junctions is testedby injecting anaesthetized snails with solutions containingperoxidase and lanthanum-nitrate. The septate junctions appearto be impermeable for the protein and inhibit permeation ofthe ion. Alkaline phosphatase is detected at the light microscope levelin the transitional and outer mantle epithelium. At the electronmicroscope level localization of alkaline phosphatase is restrictedto the apical and basal cell membranes of the same epithelia.An ATPase with low affinity to Ca2+ and Mg2+ ions is observedin the lumen of vacuoles in the proximal belt, the transitionaland the outer mantle epithelium. The possible role of the vacuolesas a site of synthesis or modification of the intercrystallinematrix is discussed. A high affinity Ca2+/Mg2+ ATPase is detectedwith the help of Electron Spectroscopic Imaging in the cellmembranes and in membranes of the rER. A model for solute transport through the epithelia to the extrapallialspace is proposed. (Received 18 August 1992; accepted 4 January 1993) 相似文献
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Negative effects of tropospheric ozone on the feed value of rice straw are mitigated by an ozone tolerance QTL 总被引:1,自引:0,他引:1
MICHAEL FREI YOSHIHISA KOHNO MATTHIAS WISSUWA HARINDER P. S. MAKKAR KLAUS BECKER 《Global Change Biology》2011,17(7):2319-2329
High surface ozone concentrations are recognized as an emerging threat to food security in Asia. This study aimed at determining the effects of ozone on the nutritive quality of rice straw, a by‐product of rice grain production and a major feed resource for ruminant livestock. Further, the question was addressed whether negative effects of ozone can be mitigated through molecular breeding. Rice plants from three different genotypes were exposed to four different ozone treatments in fumigation chambers from transplanting to maturity. These genotypes were (i) IR64, one of the most wide spread indica varieties in the world, (ii) Nipponbare, a typical japonica variety, and (iii) SL41, an ozone tolerant breeding line that carried chromosomal inserts at the ozone tolerance QTL OzT9 in the genetic background of Nipponbare. The treatments consisted of (i) charcoal filtered air, (ii) simulated ambient ozone concentration, (iii) 2 × ambient ozone concentration, and (iv) 2.5 × ambient ozone concentration. The effects of ozone on the chemical composition of straw were clearly dependent of the ozone level, and were significant even at ambient ozone concentration. Increases in crude ash, lignin and phenolics concentration adversely affected the digestibility as demonstrated in incubation experiments simulating rumen digestion in vitro. Negative ozone effects included reductions in the rate and extent of gas production due to inhibition of microbial fermentation, reduced formation of short chain fatty acids (SCFA), and a decrease in the true organic matter digestibility. The ozone tolerant genotype SL41 was less responsive to ozone than its more susceptible recurrent parent Nipponbare in terms of lignin and phenolics formation, organic matter digestibility and SCFA production. These data demonstrate that the feed quality of rice straw is affected by ozone even at ambient concentration, and that these negative effects are mitigated by the ozone tolerance QTL OzT9. 相似文献
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Tissue culture and circulating myeloblasts of avian leukemia studied in electron micrographs of ultrathin sections 总被引:1,自引:0,他引:1