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1.
A. V. Gussev N. M. Ali K. N. Abdul-Ameer S. M. Amin K. Molnár 《Systematic parasitology》1993,25(3):229-237
Four new Dactylogyrus species are described and two redescribed from cyprinids of the River Tigris, Iraq. These are as follows: Dactylogyrus barbioides n. sp. from Barbus grypus; D. orbus n. sp. from Barbus lacerta; D. barbuli n. sp. from Barbus barbulus; D. macrostomi n. sp. from Cyprinion macrostomi; D. pavlovskyi Bychowsky, 1949 from Barbus grypus and Barbus sharpeyi; and D. inutilis Bychowsky, 1949 from Barbus xanthopterus. A phylogenetic and zoogeographical analysis is presented. 相似文献
2.
The warm-season perennial switchgrass (Panicum virgatum) is a candidate bioenergy crop. To be successful, switchgrass production must be maintained on low-quality landscapes with minimal inputs while facing future climates that are expected to be more extreme and more variable. We propose that antecedent rainfall constrains how plants respond to drought, as well as subsequently recover from drought. To test this idea, we examined how six switchgrass genotypes responded to a 1-year severe drought and then recovered under normal rainfall in the following year. These plants had previously grown for 3 years under a range of dry to wet rainfall levels in a shallow-soil common garden with no fertilizer. Plants previously exposed to drought produced less biomass, and basal area after the severe drought was relieved compared to previously well-watered plants. In addition, there were legacy effects caused by plant size: plants that were larger pre-drought were more likely to survive the severe drought, and plants that were larger during the severe drought recovered more biomass, basal area, and tillers post-drought. Although genotypes differed somewhat in their responses, the size constraint was consistent across genotypes. These findings suggest that we can establish more drought-resilient switchgrass stands by, for example, planning for initial irrigation or planting during a wet year to allow plants to grow larger prior to experiencing drought. Additional studies are needed to understand whether these rainfall and size legacies persist or are transient. 相似文献
3.
Sami J Savio Lara CV Harrison Tiina Luukkaala Tomi Heinonen Prasun Dastidar Seppo Soimakallio Hannu J Eskola 《Biomedical engineering online》2010,9(1):60
Background
The accuracy of texture analysis in clinical evaluation of magnetic resonance images depends considerably on imaging arrangements and various image quality parameters. In this paper, we study the effect of slice thickness on brain tissue texture analysis using a statistical approach and classification of T1-weighted images of clinically confirmed multiple sclerosis patients. 相似文献4.
Three new Dactylogyrus species, D. rectotrabus n. sp. and D. acinacus n. sp. from Garra rufa plus D. carassobarbi n. sp. from Carassobarbus luteus are described from River Dez (Persian Gulf Basin) of Iran. Three known species, D. haplogonus from Rutilus frisii kutum, D. chalcalburni from Alburnus alburnus and Alburnoides bipunctatus, and D. pavlovskyi from Barbus sharpeyi are recorded from the Rivers Sefid (Caspian Basin), Zayandeh (Central Iran) and Dez (Tigris-Euphrates Basin), respectively. Comments on the monogenean fauna of Iranian freshwater fishes are presented. 相似文献
5.
José Rodrigues Coura Pedro Albajar Vi?as Angela CV Junqueira 《Memórias do Instituto Oswaldo Cruz》2014,109(7):856-862
Chagas disease is maintained in nature through the interchange of three cycles: the
wild, peridomestic and domestic cycles. The wild cycle, which is enzootic, has
existed for millions of years maintained between triatomines and wild mammals. Human
infection was only detected in mummies from 4,000-9,000 years ago, before the
discovery of the disease by Carlos Chagas in 1909. With the beginning of
deforestation in the Americas, two-three centuries ago for the expansion of
agriculture and livestock rearing, wild mammals, which had been the food source for
triatomines, were removed and new food sources started to appear in peridomestic
areas: chicken coops, corrals and pigsties. Some accidental human cases could also
have occurred prior to the triatomines in peridomestic areas. Thus, triatomines
progressively penetrated households and formed the domestic cycle of Chagas disease.
A new epidemiological, economic and social problem has been created through the
globalisation of Chagas disease, due to legal and illegal migration of individuals
infected by Trypanosoma cruzi or presenting Chagas disease in its
varied clinical forms, from endemic countries in Latin America to non-endemic
countries in North America, Europe, Asia and Oceania, particularly to the United
States of America and Spain. The main objective of the present paper was to present a
general view of the interchanges between the wild, peridomestic and domestic cycles
of the disease, the development of T. cruzi among triatomine, their
domiciliation and control initiatives, the characteristics of the disease in
countries in the Americas and the problem of migration to non-endemic countries. 相似文献
6.
Growth of winter cereals at low, nonfreezing temperatures is essential for the establishment of a cold-hardy state and subsequent survival of the overwintering plant. In this paper, I describe the consequences of growth and development of Secale cereale L. cv. Puma at cold-hardening temperatures with respect to leaf morphology, anatomy, and biochemistry, and with particular emphasis on their relationship to photosynthetic acclimation. Low temperature-induced structural and functional alterations at the level of ribulose bisphosphate carboxylase-oxygenase and the chloroplast thylakoid membrane are described and related to overall photosynthetic efficiency and capacity for CO2 utilization. Growth and development at cold-hardening temperatures appear to result in changes in protein conformation and membrane organization, but not in basic composition. It is proposed that developmental temperature imparts a significant effect on the assembly of these multimeric, photosynthetic components, which leads to distinct structural and functional changes. 相似文献
7.
Trendafilova-Savkova AB Todorova MN Gussev CV 《Zeitschrift für Naturforschung. C, Journal of biosciences》2003,58(11-12):817-819
The aerial parts of Artemisia chamaemelifolia Vill. afforded, in addition to five known sesquiterpene acids, a new 5-epi-cantabrenolic acid (6). 相似文献
8.
Sharif Chowdhury Jason Lloyd-Price Olli-Pekka Smolander Wayne CV Baici Timothy R Hughes Olli Yli-Harja Gordon Chua Andre S Ribeiro 《BMC systems biology》2010,4(1):143
Background
A gene network's capacity to process information, so as to bind past events to future actions, depends on its structure and logic. From previous and new microarray measurements in Saccharomyces cerevisiae following gene deletions and overexpressions, we identify a core gene regulatory network (GRN) of functional interactions between 328 genes and the transfer functions of each gene. Inferred connections are verified by gene enrichment. 相似文献9.
Amanda?G?Silva Maria?Isabel?Waddington?Achatz Ana?CV?Krepischi Peter?L?Pearson Carla?RosenbergEmail author 《Orphanet journal of rare diseases》2012,7(1):101
Background
The Li-Fraumeni syndrome (LFS), an inherited rare cancer predisposition syndrome characterized by a variety of early-onset tumors, is caused by different highly penetrant germline mutations in the TP53 gene; each separate mutation has dissimilar functional and phenotypic effects, which partially clarifies the reported heterogeneity between LFS families. Increases in copy number variation (CNV) have been reported in TP53 mutated individuals, and are also postulated to contribute to LFS phenotypic variability. The Brazilian p.R337H TP53 mutation has particular functional and regulatory properties that differ from most other common LFS TP53 mutations, by conferring a strikingly milder phenotype.Methods
We compared the CNV profiles of controls, and LFS individuals carrying either p.R337H or DNA binding domain (DBD) TP53 mutations by high resolution array-CGH.Results
Although we did not find any significant difference in the frequency of CNVs between LFS patients and controls, our data indicated an increased proportion of rare CNVs per genome in patients carrying DBD mutations compared to both controls (p=0.0002***) and p.R337H (0.0156*) mutants.Conclusions
The larger accumulation of rare CNVs in DBD mutants may contribute to the reported anticipation and severity of the syndrome; likewise the fact that p.R337H individuals do not present the same magnitude of rare CNV accumulation may also explain the maintenance of this mutation at relatively high frequency in some populations.10.
Michelle I Portugal Adriane R Todeschini Cristiana S de Lima Carlos AM Silva Ronaldo Mohana-Borges Tom HM Ottenhoff Lucia Mendonça-Previato Jose O Previato Maria CV Pessolani 《BMC microbiology》2008,8(1):75