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1.
FlordeFátima Rosas-Cárdenas Noé Durán-Figueroa Jean-Philippe Vielle-Calzada Andrés Cruz-Hernández Nayelli Marsch-Martínez Stefan de Folter 《Plant methods》2011,7(1):4
Background
Small RNAs emerged over the last decade as key regulators in diverse biological processes in eukaryotic organisms. To identify and study small RNAs, good and efficient protocols are necessary to isolate them, which sometimes may be challenging due to the composition of specific tissues of certain plant species. Here we describe a simple and efficient method to isolate small RNAs from different plant species. 相似文献2.
Sandra Dèrozier Franck Samson Jean-Philippe Tamby Cécile Guichard Véronique Brunaud Philippe Grevet Séverine Gagnot Philippe Label Jean-Charles Leplé Alain Lecharny Sébastien Aubourg 《Plant methods》2011,7(1):1-10
Background
Efficient high throughput screening systems of useful mutants are prerequisite for study of plant functional genomics and lots of application fields. Advance in such screening tools, thanks to the development of analytic instruments. Direct analysis in real-time (DART)-mass spectrometry (MS) by ionization of complex materials at atmospheric pressure is a rapid, simple, high-resolution analytical technique. Here we describe a rapid, simple method for the genetic discrimination of intact Arabidopsis thaliana mutant seeds using metabolic profiling by DART-MS.Results
To determine whether this DART-MS combined by multivariate analysis can perform genetic discrimination based on global metabolic profiling, intact Arabidopsis thaliana mutant seeds were subjected to DART-MS without any sample preparation. Partial least squares-discriminant analysis (PLS-DA) of DART-MS spectral data from intact seeds classified 14 different lines of seeds into two distinct groups: Columbia (Col-0) and Landsberg erecta (Ler) ecotype backgrounds. A hierarchical dendrogram based on partial least squares-discriminant analysis (PLS-DA) subdivided the Col-0 ecotype into two groups: mutant lines harboring defects in the phenylpropanoid biosynthetic pathway and mutants without these defects. These results indicated that metabolic profiling with DART-MS could discriminate intact Arabidopsis seeds at least ecotype level and metabolic pathway level within same ecotype.Conclusion
The described DART-MS combined by multivariate analysis allows for rapid screening and metabolic characterization of lots of Arabidopsis mutant seeds without complex metabolic preparation steps. Moreover, potential novel metabolic markers can be detected and used to clarify the genetic relationship between Arabidopsis cultivars. Furthermore this technique can be applied to predict the novel gene function of metabolic mutants regardless of morphological phenotypes. 相似文献3.
Assessing the effects of the clumping phenomenon on BRDF of a maize crop based on 3D numerical scenes using DART model 总被引:2,自引:0,他引:2
Sylvie Duthoit Valrie Demarez Jean-Philippe Gastellu-Etchegorry Emmanuel Martin Jean-Louis Roujean 《Agricultural and Forest Meteorology》2008,148(8-9):1341-1352
Inverting radiative transfer (R-T) models against remote sensing observations to retrieve key biogeophysical parameters such as leaf area index (LAI) is a common approach. Even if new inversion techniques allow the use of three-dimensional (3D) models for that purpose, one-dimensional (1D) models are still widely used because of their ease of implementation and computational efficiency. Nevertheless, they assume a random distribution of foliage elements whereas most canopies show a clumped organization. Due to that crude simplification in the representation of the canopy structure, sizeable discrepancies can occur between 1D simulations and real canopy reflectance, which may further lead to false LAI values. The present investigation aims to appraise to which extent the incorporation of a clumping index (noted λ) into 1D R-T model could improve the simulations of Bidirectional Reflectance Distribution Function (BRDF). Canopy BRDF is simulated here for three growth stages of a maize crop with the Discrete Anisotropic Radiative Transfer (DART) model in the visible and near infrared spectral bands, for two contrasted soil types (dark and bright) and different levels of heterogeneity to represent the canopy structure. 3D numerical scenes are based on in-situ structural measurements and associated BRDF simulations are thus considered as references. 1D scenarios assume either that leaves are randomly distributed (λ = 1) or clumped (λ < 1). If BRDF simulations seem globally reliable under the assumption of a random distribution in near infrared, it can also lead to relative errors on the total BRDF up to 30% in the red spectral band. It comes out that the use of a clumping index in a 1D reflectance model generally improves BRDF simulations in the red considering a bright soil, which seems relatively independent of LAI. In the near infrared, best results are usually obtained with homogeneous canopies, except with the dark soil. Clearly, influent factors are mainly the LAI and the spectral contrast between soil and leaves. 相似文献
4.
Deng H Le Rhun D Buffet JP Cotté V Read A Birtles RJ Vayssier-Taussat M 《Veterinary research》2012,43(1):15
ABSTRACT: Numerous mammal species, including domestic and wild animals such as ruminants, dogs, cats and rodents, as well as humans, serve as reservoir hosts for various Bartonella species. Some of those species that exploit non-human mammals as reservoir hosts have zoonotic potential. Our understanding of interactions between bartonellae and reservoir hosts has been greatly improved by the development of animal models for infection and the use of molecular tools allowing large scale mutagenesis of Bartonella species. By reviewing and combining the results of these and other approaches we can obtain a comprehensive insight into the molecular interactions that underlie the exploitation of reservoir hosts by Bartonella species, particularly the well-studied interactions with vascular endothelial cells and erythrocytes. 相似文献
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6.
Courant F Antignac JP Laille J Monteau F Andre F Le Bizec B 《Journal of agricultural and food chemistry》2008,56(9):3176-3184
In the present study, the occurrence of the main sex steroid hormones in milk, egg, and meat was evaluated on the basis of a highly specific gas chromatography-tandem mass spectrometry measurement method. Globally, the results indicated that targeted estrogens and androgens occurred at similar levels (concentration levels in the 10-100 ng kg (-1) range) in the analyzed muscle and milk samples. The same compounds occurred at about 10-fold higher concentrations (i.e., in the 100-1000 ng kg (-1) range) in eggs and kidney samples. More precisely, egg and milk appeared as a non-negligible sources of estradiol (i.e., 2.2 +/- 0.8 and 3.1 +/- 2.0 ng day (-1), respectively), whereas testosterone exposure is caused by ingestion of meat and/or egg (i.e., 12.2 +/- 48.2 and 5.2 +/- 2.3 ng day (-1), respectively). The provided exposure data will be further exploited in the scope of a risk assessment study regarding endocrine disruption associated with these molecules. 相似文献
7.
• Background
In the development of pure beech and pure spruce pristine forests, we assume there should be a continuous transition from full stocking to successive disintegration and, finally, total replacement of the first generational wave at the end of its lifetime, dependent on mortality due to overcrowding as well as ageing, leading newly recruited cohorts to grow up from below. 相似文献8.
Jean-Philippe Roy Luc DesC?teaux Denis DuTremblay Francis Beaudry Johanne Elsener 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(12):1257-1262
This study determined the efficacy of a 5-day extended therapy with cephapirin sodium in dairy cows chronically infected with Staphylococcus aureus. Chronically infected cows selected from 14 dairy herds in the St-Hyacinthe region, Québec were randomly allocated to a group of 31 cows treated for 5 consecutive days with 200 mg of cephapirin per quarter BID or a group of 30 untreated control cows. Bacteriological cure was determined by 3 negative bacterial cultures at 10, 24, and 31 days after treatment. The cow cure rates were 25.8% (8/31) in the treated cows and 3.3% (1/30) in the control group (P = 0.013). The quarter cure rates at first sampling post-treatment were 77.6% (38/49) and 18% (9/50) in the treated and the control groups, respectively (P < 0.0001). A 5-day extended therapy with cephapirin is effective in treating cows chronically infected with S. aureus. 相似文献
9.
In Reunion Island, tephritid fruit flies are the main pests of fruit and vegetable crops, causing severe yield losses. Instead of the curative approach to reducing populations, this study focused on a particular sanitation technique, which forms the basis of Integrated Pest Management (IPM) in this context, using a tent-like structure called an “augmentorium” the aim of which is to contribute to controlling these pests. This structure sequesters adult flies emerging from infested fruit while allowing the parasitoids to escape, via a net placed at the top of the structure. The size of four nets was tested in the laboratory in order to include the most effective one in an augmentorium prototype adapted to the conditions of Reunion Island. The mesh finally selected (hole area 3.00 mm2) proved to be perfectly effective with 100% sequestration of adult flies (Ceratitis capitata, Bactrocera cucurbitae, Bactrocera zonata). In addition, 100% of the parasitoids (Fopius arisanus and Psyttalia fletcheri) were able to escape from the cage through the mesh if they chose to do so. Farmers were enthusiastic about using the augmentorium prototype. Implications for the use of this technique in Reunion Island are discussed. 相似文献
10.
Adrian Boswood Sonya G. Gordon Jens Häggström Martin Vanselow Gerhard Wess Rebecca L. Stepien Mark A. Oyama Bruce W. Keene John Bonagura Kristin A. MacDonald Mark Patteson Sarah Smith Philip R. Fox Karen Sanderson Richard Woolley Viktor Szatmári Pierre Menaut Whitney M. Church M. Lynne O'Sullivan Jean-Philippe Jaudon Jan-Gerd Kresken John Rush Kirstie A. Barrett Steven L. Rosenthal Ashley B. Saunders Ingrid Ljungvall Michael Deinert Eric Bomassi Amara H. Estrada Maria J. Fernandez Del Palacio N. Sydney Moise Jonathan A. Abbott Yoko Fujii Alan Spier Michael W. Luethy Roberto A. Santilli Masami Uechi Anna Tidholm Christoph Schummer Philip Watson 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(3):1108-1118