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41.
Roosa AE Laitinen Suvi Broholm Victor A Albert Teemu H Teeri Paula Elomaa 《BMC plant biology》2006,6(1):11-18
Background
The inflorescence of the cut-flower crop Gerbera hybrida (Asteraceae) consists of two principal flower types, ray and disc, which form a tightly packed head, or capitulum. Despite great interest in plant morphological evolution and the tractability of the gerbera system, very little is known regarding genetic mechanisms involved in flower type specification. Here, we provide comparative staging of ray and disc flower development and microarray screening for differentially expressed genes, accomplished via microdissection of hundreds of coordinately developing flower primordia. 相似文献42.
Vesa P Hytönen Juha AE Määttä Einari A Niskanen Juhani Huuskonen Kaisa J Helttunen Katrin K Halling Henri R Nordlund Kari Rissanen Mark S Johnson Tiina A Salminen Markku S Kulomaa Olli H Laitinen Tomi T Airenne 《BMC structural biology》2007,7(1):8
Background
The chicken genome contains a BBP-A gene showing similar characteristics to avidin family genes. In a previous study we reported that the BBP-A gene may encode a biotin-binding protein due to the high sequence similarity with chicken avidin, especially at regions encoding residues known to be located at the ligand-binding site of avidin. 相似文献43.
Max A Little Patrick E McSharry Stephen J Roberts Declan AE Costello Irene M Moroz 《Biomedical engineering online》2007,6(1):23
Background
Voice disorders affect patients profoundly, and acoustic tools can potentially measure voice function objectively. Disordered sustained vowels exhibit wide-ranging phenomena, from nearly periodic to highly complex, aperiodic vibrations, and increased "breathiness". Modelling and surrogate data studies have shown significant nonlinear and non-Gaussian random properties in these sounds. Nonetheless, existing tools are limited to analysing voices displaying near periodicity, and do not account for this inherent biophysical nonlinearity and non-Gaussian randomness, often using linear signal processing methods insensitive to these properties. They do not directly measure the two main biophysical symptoms of disorder: complex nonlinear aperiodicity, and turbulent, aeroacoustic, non-Gaussian randomness. Often these tools cannot be applied to more severe disordered voices, limiting their clinical usefulness. 相似文献44.
SHIGERU A. AE 《Systematic Entomology》1979,4(1):1-16
Abstract. Adults of different species of the genus Papilio can easily be mated by hand-pairing. The data on egg hatchability, adult formation and F1 fertility in these interspecific hybrids show notable variations according to the crosses. Using these data, values of a differentiation index for each cross were calculated. These estimates of genetic distance were then used to study the phylo-genetic relationships of the species involved. The data are consistent with the existence of the following groups, each consisting of closely related species: the black Papilio supergroup, the Papilio memnon group, the P.demoleus group, the P.xuthus group, the P.machaon group, the P.bianor group, the P.glaucus group and the P.troilus group. The phylogenetic relationships revealed by these data generally coincide with the relationships established by classical taxonomy. In cases where there are differences of opinion among taxonomists, the writer's data usually support one or other of them. 相似文献
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This study uses document analysis and interviews to explore how the use of arguments for biodiversity and ecosystem services has evolved in recent years in the water industry in England and Wales, with a focus on investments in catchment management programmes. Changes to land management practices within catchment areas can lead to improved water quality and lower treatment costs, and also ancillary benefits to the natural environment and various stakeholders. Our analysis reveals the increasing effectiveness of arguments associated with ecosystem service values in enabling the industry regulator (Ofwat) to support water industry investments in catchment-level conservation projects. Ofwat has adopted a much more flexible approach to regulation, moving from initial resistance to ecosystem service framings and a dominant focus on financial benefits to customers, to acceptance that customers have a legitimate interest in environmental quality and a willingness to accept some ‘beneficiary pays’ solutions. Companies are now required by Ofwat to include environmental impacts in cost-benefit analysis of investments, alongside assessment of customer preferences and support. This has facilitated investments in catchment management with positive results for water companies, customers, farmers and the natural environment. The shift in arguments in this industry matches a broader shift at European and UK levels towards greater use of economic evidence and payment instruments. The challenge now is to stabilise a secure regulatory environment in which companies are encouraged to pursue innovative methods to benefit the wider interest of customers and the natural environment, today and in the future. Arguments based on the value of water quality improvements and of the wider associated ecosystem services benefits have been, and remain, a key tool for achieving the environmental improvements and economic efficiency gains associated with successful catchment management initiatives. 相似文献
46.
A reassessment of decreased amino acid accumulation by ehrlich ascites tumor cells in the presence of metabolic inhibitors 总被引:2,自引:0,他引:2 下载免费PDF全文
This study was undertaken to examine the mechanism by which metabolic inhibition reduces amino acid active transport in ehrlich ascites tumor cells. At 37 degrees C the metabolic inhibitor combination 0.1 mM 2,4-dinitrophenol (DNP) + 10 mM 2- deoxy-D-glucose (DOG) reduced the cell ATP concentration to 0.10- 0.15 mM in less than 5 min. This inhibition was associated with a 20.6 percent +/- 6.4 percent (SD) decrease in the initial influx of α-aminoisobutyric acid (AIB), and a two- to fourfold increase in the unidirectional efflux. These effects could be dissociated from changes in cell Na(+) or K(+) concentrations. Cells incubated to the steady state in 1.0-1.5 mM AIB showed an increased steady-state flux in the presence of DNP + DOG. Steady- state fluxes were consistent with trans-inhibition of AIB influx and trans-stimulation of efflux in control cells, but trans- stimulation of both fluxes in inhibited cells. In spite of the reduction of the cell ATP concentration to less than 0.15 mM and greatly reduced transmembrane concentration gradients of Na(+) and K(+), cells incubated to the steady state in the presence of the inhibitors still established an AIB distribution ration 13.8 +/- 2.6. The results are interpreted to indicate that a component of the reduction of AIB transport produced by metabolic inhibition is attributable to other actions in addition to the reduction of cation concentration gradients. Reduction of cell ATP alone is not responsible for the effects of metabolic inhibition, and both the transmembrane voltage and direct coupling to substrate oxidation via plasma-membrane-bound enzymes must be considered as possible energy sources for amino acid active transport. 相似文献
47.
Paulo Breinis Flavio Geraldes Alves Camila AE Alves Rafael G Cintra Débora Almeida Priscila C Passarelli Camila Domingues Talita Gerbim Régia Gasparetto Luiz Carlos de Abreu Vitor E Valenti Adriana Gonçalves de Oliveira Carlos Bandeira de Mello Monteiro Rubens Wajnzstejn 《BMC neurology》2014,14(1):1-4
Background
The Mulvihill-Smith Syndrome was first recognized in 1975. After the recognition of the Mulvihill-Smith Syndrome, ten cases have been described.Case presentation
This article describes the eleventh case of this syndrome in a male patient, 24 years-old with short stature and microcephaly with mild cognitive impairment, deafness and allergic conjunctivitis. The patient was hospitalized several times for repeated infections, and the presence of multiple melanocytic nevi on his skin was noticed.Conclusions
Based on the entire set of signs and symptoms presented in our study, it was diagnosed the patient with Mulvihill-Smith Syndrome. 相似文献48.
Philipp Diebolder Armin Keller Stephanie Haase Anne Schlegelmilch Jonathan D Kiefer Tamana Karimi Tobias Weber Gerhard Moldenhauer Roland Kehm Anna M Eis-Hübinger Dirk J?ger Philippe A Federspil Christel Herold-Mende Gerhard Dyckhoff Roland E Kontermann Michaela AE Arndt Jürgen Krauss 《MABS-AUSTIN》2014,6(1):130-142
The development of efficient strategies for generating fully human monoclonal antibodies with unique functional properties that are exploitable for tailored therapeutic interventions remains a major challenge in the antibody technology field. Here, we present a methodology for recovering such antibodies from antigen-encountered human B cell repertoires. As the source for variable antibody genes, we cloned immunoglobulin G (IgG)-derived B cell repertoires from lymph nodes of 20 individuals undergoing surgery for head and neck cancer. Sequence analysis of unselected “LYmph Node Derived Antibody Libraries” (LYNDAL) revealed a naturally occurring distribution pattern of rearranged antibody sequences, representing all known variable gene families and most functional germline sequences. To demonstrate the feasibility for selecting antibodies with therapeutic potential from these repertoires, seven LYNDAL from donors with high serum titers against herpes simplex virus (HSV) were panned on recombinant glycoprotein B of HSV-1. Screening for specific binders delivered 34 single-chain variable fragments (scFvs) with unique sequences. Sequence analysis revealed extensive somatic hypermutation of enriched clones as a result of affinity maturation. Binding of scFvs to common glycoprotein B variants from HSV-1 and HSV-2 strains was highly specific, and the majority of analyzed antibody fragments bound to the target antigen with nanomolar affinity. From eight scFvs with HSV-neutralizing capacity in vitro, the most potent antibody neutralized 50% HSV-2 at 4.5 nM as a dimeric (scFv)2. We anticipate our approach to be useful for recovering fully human antibodies with therapeutic potential. 相似文献
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