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91.
92.
A.C. Gonçalves T.D. Matos H.R. Simões-Teixeira M. Pimenta Machado M. Simão Ó.P. Dias M. Andrea G. Fialho H. Caria 《Gene》2014
Low-frequency sensorineural hearing loss (LFSNHL) is an unusual type of HL in which frequencies at 2000 Hz and below are predominantly affected. Most of the families with LFSNHL carry missense mutations in WFS1 gene, coding for wolframin. 相似文献
93.
N. G. Averina E. L. Nedved’ R. A. Shcherbakov I. V. Vershilovskaya E. B. Yaronskaya 《Russian Journal of Plant Physiology》2014,61(5):679-687
Growing of winter rape (Brassica napus L.) plants for 7–8 days in the presence of a sulfonylurea herbicide Magnum (methsulfuron methyl; 200 and 500 mg/L) exerted an organ-specific influence on the seedlings: suppressed hypocotyl and root growth and increased the accumulation of fresh weight of cotyledonary leaves. Exogenous 5-aminolevulinic acid (ALA; 0.1, 1.0, and 10 mg/L) partially negated the adverse effect of Magnum on the length and fresh weight of roots and hypocotyls and stimulated the development of cotyledons. The herbicide suppressed the activity of ascorbate peroxidase (APX). The addition of ALA to the 200 mg/L herbicide solution caused a steady activation of APX as compared with the effect of herbicide alone. In plants grown on Magnum solutions, the activity of glutathione reductase (GR) rose. Positive effect of exogenous ALA was only observed when 500 mg/L herbicide was used (Magnum-500 type of treatment). In plants grown on the Magnum solution, the content of reduced and oxidized forms of glutathione rose. In contrasty, exogenous ALA reduced the total content of glutathione but in this case the ratio between its reduced and oxidized forms rose. In the presence of the herbicide, the content of anthocyans considerably decreased and upon the addition of exogenous ALA their levels rose. In rape plants treated with Magnum, the ability to generate superoxide anion radical was essentially the same as in control plants; however, the content of hydrogen peroxide (H2O2) therein rose. The addition of ALA to the herbicide reduced the ability to generate superoxide anion radical and the level of H2O2. The activity of acetolactate synthase remained on the control level when 200 mg/L Magnum was used, decreased in the plants of Magnum-500 treatment, and rose upon the addition of exogenous ALA to this type of treatment. It was concluded that ALA had a positive effect on the development of winter rape resistance to Magnum via stimulation of growth processes, activation of APX and GR, predominant elevation of the content of reduced glutathione and anthocyans, and partial recovery of acetolactate synthase activity, which on the whole caused a decrease in the H2O2 level and in the ability of plants to generate superoxide anion radical. 相似文献
94.
Paraskevi Agrafioti Christos G. Athanassiou Thomas N. Vassilakos George Vlontzos Frank H. Arthur 《PloS one》2015,10(11)
We evaluated knockdown caused by four insecticides: alpha-cypermethrin, chlorfenapyr, pirimiphos-methyl and fipronil against adults of Tribolium confusum Jacquelin Duval, the confused flour beetle and Oryzaephilus surinamensis (L.), the sawtoothed grain beetle. Bioassays were conducted on concrete and metal surfaces. Adults of the tested species were exposed on both surfaces treated with the above insecticides at two doses (low and high). Knockdown assessment was done after 15, 30 and 60 min of adult exposure in the treated surfaces. Also, after 1, 3, 5, 7 and 14 d of exposure, a lethality index was calculated with an equation resulting to values from 0 to 100, where 100 indicated complete mortality and 0 complete survival. We also developed a lethality index by ranking each adult on each surface from 0 to 4, 0: adults moved normally, 1: adults were knocked down, but were able to walk for short intervals, 2: adults were knocked down and unable to walk, but with visible movement of antennae etc., 3: adults were knocked down, with very minimal movement of the tarsi and the antennae and 4: adults were dead (no movement). Knockdown of adults immediately after exposure (15–60 min) was higher for pirimiphos-methyl followed by alpha-cypermethrin, for both dose rates tested and species, but only on the metal surface. The lethality index was nearly 100 for all insecticides after 5d of exposure for O. surinamensis, while for T. confusum the adult lethality index was considerably lower for alpha-cypermethrin, suggesting that that recovery from knockdown occurred. Chlorfenapyr was the only insecticide that was more effective on concrete than on metal, while the reverse was noted for the other three insecticides. These results show that knockdown has different levels, which can be used as indicators of insect mortality or recovery. 相似文献
95.
Lawrence C. Hamilton Joel Hartter Mary Lemcke-Stampone David W. Moore Thomas G. Safford 《PloS one》2015,10(9)
A simple question about climate change, with one choice designed to match consensus statements by scientists, was asked on 35 US nationwide, single-state or regional surveys from 2010 to 2015. Analysis of these data (over 28,000 interviews) yields robust and exceptionally well replicated findings on public beliefs about anthropogenic climate change, including regional variations, change over time, demographic bases, and the interacting effects of respondent education and political views. We find that more than half of the US public accepts the scientific consensus that climate change is happening now, caused mainly by human activities. A sizable, politically opposite minority (about 30 to 40%) concede the fact of climate change, but believe it has mainly natural causes. Few (about 10 to 15%) say they believe climate is not changing, or express no opinion. The overall proportions appear relatively stable nationwide, but exhibit place-to-place variations. Detailed analysis of 21 consecutive surveys within one fairly representative state (New Hampshire) finds a mild but statistically significant rise in agreement with the scientific consensus over 2010–2015. Effects from daily temperature are detectable but minor. Hurricane Sandy, which brushed New Hampshire but caused no disaster there, shows no lasting impact on that state’s time series—suggesting that non-immediate weather disasters have limited effects. In all datasets political orientation dominates among individual-level predictors of climate beliefs, moderating the otherwise positive effects from education. Acceptance of anthropogenic climate change rises with education among Democrats and Independents, but not so among Republicans. The continuing series of surveys provides a baseline for tracking how future scientific, political, socioeconomic or climate developments impact public acceptance of the scientific consensus. 相似文献
96.
E. Ciani P. Crepaldi L. Nicoloso E. Lasagna F. M. Sarti B. Moioli F. Napolitano A. Carta G. Usai M. D'Andrea D. Marletta R. Ciampolini V. Riggio M. Occidente D. Matassino D. Kompan P. Modesto N. Macciotta P. Ajmone‐Marsan F. Pilla 《Animal genetics》2014,45(2):256-266
Italy counts several sheep breeds, arisen over centuries as a consequence of ancient and recent genetic and demographic events. To finely reconstruct genetic structure and relationships between Italian sheep, 496 subjects from 19 breeds were typed at 50K single nucleotide polymorphism loci. A subset of foreign breeds from the Sheep HapMap dataset was also included in the analyses. Genetic distances (as visualized either in a network or in a multidimensional scaling analysis of identical by state distances) closely reflected geographic proximity between breeds, with a clear north–south gradient, likely because of high levels of past gene flow and admixture all along the peninsula. Sardinian breeds diverged more from other breeds, a probable consequence of the combined effect of ancient sporadic introgression of feral mouflon and long‐lasting genetic isolation from continental sheep populations. The study allowed the detection of previously undocumented episodes of recent introgression (Delle Langhe into the endangered Altamurana breed) as well as signatures of known, or claimed, historical introgression (Merino into Sopravissana and Gentile di Puglia; Bergamasca into Fabrianese, Appenninica and, to a lesser extent, Leccese). Arguments that would question, from a genomic point of view, the current breed classification of Bergamasca and Biellese into two separate breeds are presented. Finally, a role for traditional transhumance practices in shaping the genetic makeup of Alpine sheep breeds is proposed. The study represents the first exhaustive analysis of Italian sheep diversity in an European context, and it bridges the gap in the previous HapMap panel between Western Mediterranean and Swiss breeds. 相似文献
97.
G Berruti 《Cell biology international reports》1991,15(10):917-927
We have previously reported the presence in human spermatozoa of calpactin II, a calcium-binding component of the membrane skeleton (Berruti, Exper. Cell Res. 179, 374, 1988). Reported here are studies which show the ability of sperm calpactin II to interact with filamentous actin and acidic phospholipids in a Ca(2+)-dependent fashion. At high Ca2+ concentrations (greater than 1 mM) sperm calpactin II binds to actin filament and it is resolubilized by EGTA. Liposome binding experiments reveal that sperm calpactin II does associate with phospholipidic vesicles at micromolar free Ca2+ levels. These interaction properties together with the cellular distribution of the protein revealed by immunofluorescence analysis in Ca2+ and ionophore A23187-treated human spermatozoa allow to hypothesize a physiological role for calpactin II in sperm Ca(2+)-mediated events. 相似文献
98.
para-hydroxybenzoate as an intermediate in the anaerobic transformation of phenol to benzoate 总被引:4,自引:0,他引:4
Anaerobic phenol transformation was studied using a consortium which transformed phenol to benzoate without complete mineralization of benzoate. Products of monofluorophenol transformation indicated para-carboxylation. Phenol and benzoate were detected during para-hydroxybenzoate (p-OHB) degradation. p-OHB was detected in phenol-transforming cultures containing 6-hydroxynicotinic acid (6-OHNA), a structural analogue of p-OHB, or at elevated initial concentrations of phenol (greater than or equal to 5 mM), or benzoate (greater than or equal to 10 mM). 相似文献
99.
I. G. Macintyre K. Rützler J. N. Norris K. P. Smith S. D. Cairns K. E. Bucher R. S. Steneck 《Coral reefs (Online)》1991,10(3):167-174
Submersible observations and collections reveal that a probable relict reef off the west coast of Barbados has a rich cover of sponges, along with algae and scattered corals, on a substrate of algal nodules in a muddy-sand matrix. The collections provide new data on the distributions of these fauna. This relict reef is about 20 km long, has a relief of up to 10 m, and is established at a depth of 80 m. Relict shallow-water features in other areas at similar depths along with data from core holes drilled off the south coast of Barbados suggest that this reef was probably established about 12,000 years ago and existed for no more than 2,000 years, during the Holocene sea-level transgression. 相似文献
100.