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C. SOLIANI J. RONDAN‐DUEÑAS M. B. CHIAPPERO M. MARTÍNEZ E. GARCÍA DA ROSA C. N. GARDENAL 《Medical and veterinary entomology》2010,24(3):316-323
Aedes aegypti (L.) (Diptera: Culicidae), the main vector of yellow fever and dengue viruses, was eradicated from Argentina between 1955 and 1963, but reinvaded the country in 1986. In Uruguay, the species was reintroduced in 1997. In this study we used highly polymorphic inter‐simple sequence repeats (ISSR) markers to analyse the genetic structure of Ae. aegypti populations from Uruguay and northeastern Argentina to identify possible colonization patterns of the vector. Overall genetic differentiation among populations was high (FST = 0.106) and showed no correlation with geographic distance, which is consistent with the short time since the reintroduction of the species in the area. Differentiation between pairs of Argentine populations (FST 0.072 to 0.221) was on average higher than between Uruguayan populations (FST?0.044 to 0.116). Bayesian estimation of population structure defined four genetic clusters and most populations were admixtures of two of them: Mercedes and Treinta y Tres (Uruguay) were mixtures of clusters 1 and 3; Salto (Uruguay) and Paraná (Argentina) of clusters 1 and 4; Fray Bentos (Uruguay) of clusters 2 and 3, and Gualeguaychú (Argentina) of clusters 2 and 3. Posadas and Buenos Aires in Argentina were fairly genetically homogeneous. Our results suggest that Ae. aegypti recolonized Uruguay from bordering cities in Argentina via bridges over the Uruguay River and also from Brazil. 相似文献
323.
1. The life history of wood feeders was modelled in order to explain the multiseasonality of development and the great variability of adult size in this group. 2. The model was parameterised with experimental bioenergetic and reproductive data for the xylem feeder Aredolpona rubra (Coleoptera: Cerambycidae). 3. The length of the developmental period, which together with food quality directly determines adult size and indirectly determines the number of eggs laid, was optimised. 4. The results show that multi‐seasonal larval development maximises fitness under conditions of low food quality, relatively low predation pressure, and the presence of hostile periods during the year. 5. The variability of the number of seasons needed to complete development within a wood‐feeder population is a consequence of development time optimisation and the unavoidable extension of the egg‐laying period. These insects have an evolutionary dilemma: to eclose late in a given season at smaller size, bringing about low egg production and low offspring value, or to grow bigger to the next season, jeopardising their lives. 6. The results of the model predict wood‐feeder developmental patterns that depend on the tree tissue inhabited. 相似文献
324.
Abstract: The first mygalomorph spiders from the Lower Cretaceous Crato Lagerstätte of Cearà Province, north-east Brazil, are described, from adult males and females, in two new genera and species: Cretadiplura ceara Selden, gen. et sp. nov. and Dinodiplura ambulacra Selden, gen. et sp. nov. They belong to the extant family Dipluridae, hitherto known as fossils only from Tertiary strata; thus this occurrence extends the family record by some 90 myr. 相似文献
325.
Effects of MEK inhibitor U0126 on meiotic progression in mouse oocytes: microtuble organization, asymmetric division and metaphase Ⅱ arrest 总被引:1,自引:0,他引:1
CHAO TONG HENG YU FAN DA YUAN CHEN XIANG FEN SONG HEIDE SCHATTEN QING YUAN SUNI State Key Laboratory of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing China. Department of Veterinary Pathobiology University of Missouri-Columbia MO USA 《Cell research》2003,13(5):375-384
In this study we used U0126, a potent and specific inhibitor of MEK, to study the roles of MEK/ERK/p90~(rsk) signaling pathway in the meiotic cell cycle of mouse oocytes. The phosphorylation of MAP kinase and p90~(rsk) in the oocytes treated with 1.5 μM U0126 was the same as that in oocytes cultured in drug-free medium. With 1.5 μM U0126 treatment, the spindles appeared normal as they formed in oocytes, but failed to maintain its structure. Instead, the spindle lost one pole or elongated extraordinarily. After further culture, some oocytes extruded gigantic polar bodies (>30 μm) that later divided into two small ones. Some oocytes underwent symmetric division and produced two equal-size daughter cells in which normal spindles formed. In oocytes with different division patterns, MAP kinase was normally phosphorylated. When the concentration of U0126 was increased to 15 mM, the phosphorylation of both MAPK and p90~(rsk) were inhibited, while symmetric division was decreased. When incubating in medium c 相似文献
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O. V. LEDESMA AÍDA P. DE RUIZ HOLGADO G. OLIVER GRACIELA S. DE GIORI P. RAIBAUD J. V. GALPIN 《Journal of applied microbiology》1977,42(1):123-133
The composition of a synthetic medium supporting the growth of lactobacilli is given (Table 1). The medium, containing glucose, amino acids, vitamins, mineral salts, purines and pyrimidines, allows the study of nutritional requirements of different strains of lactobacilli under identical environmental conditions. It was found that all the strains tested needed L-glutamic acid, L-valine and L-leucine, and a group of them also required L-arginine, L-tyrosine and L-tryptophan. Some strains required vitamins, e.g. L. bulgaricus (pantothenic acid), L. fermenti (pantothenic acid and niacin). These results are compared with those found by others employing different media. 相似文献
328.
JANA LEONG-KORNIKOVÁ OTAKAR ÍDA SIRIL WIJESUNDARA KAROL MARHOLD 《Botanical journal of the Linnean Society. Linnean Society of London》2008,157(1):37-46
Although Curcuma L. (Zingiberaceae) is a conserved name, with C. longa L. as its conserved type, the type of C. longa is still uncertain. Numerous discussions about the identity of the taxon called C. longa by Linnaeus have been followed by various attempts to rename turmeric, suggestions as how to settle the type and proposals to conserve the name from a later author in order to stabilize the situation. Unfortunately, none of the previous proposals can be upheld for reasons which are discussed in this article. A lectotype is selected from extant material examined by Linnaeus and an epitype collected near the type locality is designated here. The identity of C. longa is discussed and a colour plate of the species is included. Synonyms of C. longa and their types are discussed and notes on the variability of C. longa are provided. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 37–46. 相似文献
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330.
目的:探索评价基质效应在化学发光免疫分析中对甲状腺功能五项指标的影响。方法:选取甲状腺功能五项高值血清,用10种基质牛血清、马血清、山羊血清、水解明胶、BSA、PBS、生理盐水、正常人血清、甲减人血清、甲亢人血清分别对T3、T4、FT3、FT4、TSH的高值血清进行倍比稀释,观察基质效应,另将10种基质用考马斯亮兰法检测蛋白含量,分析蛋白含量与基质效应的关系。结果:T3项目牛血清、水解明胶、BSA有明显基质效应;T4和FT3项目牛血清、水解明胶、BSA、PBS、生理盐水有明显基质效应;FT4项目牛血清、马血清、水解明胶、BSA、PBS、生理盐水有明显基质效应;TSH项目没有发现基质效应,正常人血清、甲减人血清和甲亢人血清对甲状腺功能五项无基质效应。检测结果显示蛋白含量多少与基质效应无关。结论:人血清基质是用于稀释样本,基质效应最小的液体,针对个体差异性进行的选择,稀释T3、T4、FT3、FT4高值血清选择甲减人血清,稀释TSH高值血清选择甲亢人血清,可以得到较为满意的结果。 相似文献