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151.
Julianne M. O��Reilly-Wapstra Jules S. Freeman Noel W. Davies Ren�� E. Vaillancourt Hugh Fitzgerald Brad M. Potts 《Tree Genetics & Genomes》2011,7(3):485-498
Terpenes are a diverse group of plant secondary metabolites that mediate a plethora of ecological interactions in many plant species. Despite increasing research into the genetic control of important adaptive traits in some plant species, the genetic control of terpenes in forest tree species is still relatively poorly studied. In this study, we use quantitative genetic and quantitative trait loci (QTL) analysis to investigate the genetic control of foliar terpenes in an ecologically and commercially important eucalypt species, Eucalyptus globulus. We show a moderate to high within-family broad-sense heritability and significant genetic basis to the variation in 14 of the 16 terpenes assayed. This is the first report of QTL for terpenes in this species. Eleven QTL influenced the terpenes overall. One QTL on linkage group 6 affected six of the seven different sesquiterpenes assayed (plus one monoterpene), which, in combination with highly significant correlations between these compounds, argues that their variation is influenced by a QTL with pleiotropic effect early in the biosynthetic pathway. We examine the homology of these QTL to those found in a closely related eucalypt, Eucalyptus nitens, and provide evidence that both common and unique QTL influence terpene levels. 相似文献
152.
Inge Santman-Berends Saskia Luttikholt René Van den Brom Gerdien Van Schaik Maaike Gonggrijp Han Hage Piet Vellema 《PloS one》2014,9(8)
The aim of this study was to estimate the quantity of antibiotics and classes of antibiotics used in the small ruminant industry in the Netherlands in 2011 and 2012. Twelve large veterinary practices, located throughout the Netherlands were selected for this study. All small ruminant farms associated with these practices that had complete records on the quantity of antibiotics prescribed were included. The veterinary practices provided data on all antibiotics prescribed, and the estimated animal used daily dose of antibiotics per year (AUDD/Y) was calculated for each farm. The median AUDD/Y in small ruminant farms was zero in both years (mean 0.60 in 2011, and 0.62 in 2012). The largest quantity of antibiotic use was observed in the professional goat industry (herds of ≥32 goats) with a median AUDD/Y of 1.22 in 2011 and 0.73 in 2012. In the professional sheep industry (flocks of ≥32 sheep), the median AUDD/Y was 0 in 2011 and 0.10 in 2012. In the small scale industry (flocks or herds of <32 sheep or goats), the median AUDD/Y never exceeded 0. The most frequently prescribed antibiotics in the small scale industry and professional sheep farms belonged to the penicillin class. In professional goat farms, antibiotics of the aminoglycoside class were most frequently prescribed. This study provides the first assessment on the quantity of antibiotic use in the small ruminant industry. Given a comparable attitude towards antibiotic use, these results might be valid for small ruminant populations in other north-western European countries as well. The antibiotic use in the small ruminant industry appeared to be low, and is expected to play a minor role in the development of antibiotic resistance. Nevertheless, several major zoonotic bacterial pathogens are associated with the small ruminant industry, and it remains important that antibiotics are used in a prudent way. 相似文献
153.
154.
Yuxiang Yao Hongzhi Tang Huixue Ren Hao Yu Lijuan Wang Ping Xu 《Journal of bacteriology》2012,194(20):5714-5715
We announce a 4.63-Mb genome assembly of an isolated bacterium that is the first sequenced nicotine-degrading Arthrobacter strain. Nicotine catabolism genes of the nicotine-degrading plasmid pAO1 were predicted, but plasmid function genes were not found. These results will help to better illustrate the molecular mechanism of nicotine degradation by Arthrobacter. 相似文献
155.
René Gibert 《Helgoland Marine Research》1966,14(1-4):148-167
A simple physico-chemical model of the excitable cell is represented by a peculiar chemically active ion exchange medium. It reveals some properties of natural cells: chemical and electrical irritability, all or none effect, summation of stimuli, electrotonus, refractory periods, periodical oscillations, action potentials, conduction of impulse. This model is based upon oversimplified assumptions, and a further investigation into more details is required. 相似文献
156.
M. W. J. Crosland S. X. Ren J. F. A. Traniello 《Ethology : formerly Zeitschrift fur Tierpsychologie》1998,104(1):57-67
To investigate division of labour in Reticulitermes fukienensis, worker and larval subgroups were established in laboratory cultures and task performance patterns of different-sized workers and larvae were recorded. Five categories of subgroups were established based on head width differences: small larvae (SL); large larvae (LL); small workers (SW); medium workers (MW); and large workers (LW). Subgroups were compared for their ability to carry out the following tasks: tunnel construction; covered gallery construction; gallery repair; and feeding. Larval subgroups were found to carry out none of the tasks investigated. They did not feed or build covered galleries or underground tunnels. Temporal polyethism occurred among workers of different size groups. Covered foraging galleries were exclusively built and tunnels were predominantly built by older workers (i.e. MW and especially LW). Remarkably, most SW were apparently unable to burrow into the soil, something that all LW did within 3 d and 95% of MW did within 5 d. Surprisingly, LW ate 8.5 and 65.5 times as much food (i.e. filter paper) as MW and SW, respectively, although their average body weights were, respectively, only approximately two and four times that of MW and SW. MW carried out all four tasks that LW performed, although MW were typically less efficient. This contrasts with the hypothesis that different instars of termites should carry out different non-overlapping tasks. Large workers carried out most of all tasks compared with other worker sizes. The only exception was for gallery repair where repair rate by LW did not differ significantly from MW. The predominance of tasks carried out by larger (i.e. older) workers indicates a possible new pattern for division of labour in these lower termites. This contrasts with the pattern of organization of division of labour in the social Hymenoptera. 相似文献
157.
Opoku Yeboah Kwaku Liu Zhihang Afrifa Justice Khoso Mir Hassan Ren Guiping Li Deshan 《International journal of peptide research and therapeutics》2020,26(1):107-119
International Journal of Peptide Research and Therapeutics - Fibroblast growth factor-21 (FGF21) is a member of the family of fibroblast growth factors (FGFs). FGF21 (synthesized by many organs)... 相似文献
158.
Electrically controlled lateral shift by an electro-optic crystal prism is studied theoretically. The resonance point of excitation of guided-wave surface plasmon resonance (GWSPR) can be controlled by altering the refractive index of the prism. That is to say, the positions corresponding to the least reflectivity and the largest lateral shift could be conveniently modulated while the lithium niobate prism is operated in an external electric field. The maximal lateral shift is obtained at the excitation of GWSPR when the thickness of the silver film is optimized. The results of numerical simulations confirm theoretical calculation.
相似文献159.
Plasmonics - The surface-enhanced Raman scattering (SERS) is widely used in chemical analysis and environmental monitoring. Herein, the Au@MoS2@Au three core–shell hierarchical architecture... 相似文献
160.
Da Wo Jinxiao Chen Qiongyu Li En Ma Hongwei Yan Jun Peng Weidong Zhu Yong Fang Dan‐ni Ren 《Journal of cellular and molecular medicine》2020,24(16):9466-9471
Vascular endothelial growth factor (VEGF) is a well‐known angiogenic factor, however its ability in promoting therapeutic angiogenesis following myocardial infarction (MI) is limited. Here, we aimed to investigate whether dual treatment with insulin‐like growth factor binding protein‐4 (IGFBP‐4), an agent that protects against early oxidative damage, can be effective in enhancing the therapeutic effect of VEGF following MI. Combined treatment with IGFBP‐4 enhanced VEGF‐induced angiogenesis and prevented cell damage via enhancing the expression of a key angiogenic factor angiopoietin‐1. Dual treatment with the two agents synergistically decreased cardiac fibrosis markers collagen‐I and collagen‐III following MI. Importantly, while the protective action of IGFBP‐4 occurs at an early stage of ischemic injury, the action of VEGF occurs at a later stage, at the onset angiogenesis. Our findings demonstrate that VEGF treatment alone is often not enough to protect against oxidative stress and promote post‐ischemic angiogenesis, whereas the combined treatment with IGFBP4 and VEGF can utilize the dual roles of these agents to effectively protect against ischemic and oxidative injury, and promote angiogenesis. These findings provide important insights into the roles of these agents in the clinical setting, and suggest new strategies in the treatment of ischemic heart disease. 相似文献