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排序方式: 共有191条查询结果,搜索用时 31 毫秒
101.
Giraud E Moulin L Vallenet D Barbe V Cytryn E Avarre JC Jaubert M Simon D Cartieaux F Prin Y Bena G Hannibal L Fardoux J Kojadinovic M Vuillet L Lajus A Cruveiller S Rouy Z Mangenot S Segurens B Dossat C Franck WL Chang WS Saunders E Bruce D Richardson P Normand P Dreyfus B Pignol D Stacey G Emerich D Verméglio A Médigue C Sadowsky M 《Science (New York, N.Y.)》2007,316(5829):1307-1312
Leguminous plants (such as peas and soybeans) and rhizobial soil bacteria are symbiotic partners that communicate through molecular signaling pathways, resulting in the formation of nodules on legume roots and occasionally stems that house nitrogen-fixing bacteria. Nodule formation has been assumed to be exclusively initiated by the binding of bacterial, host-specific lipochito-oligosaccharidic Nod factors, encoded by the nodABC genes, to kinase-like receptors of the plant. Here we show by complete genome sequencing of two symbiotic, photosynthetic, Bradyrhizobium strains, BTAi1 and ORS278, that canonical nodABC genes and typical lipochito-oligosaccharidic Nod factors are not required for symbiosis in some legumes. Mutational analyses indicated that these unique rhizobia use an alternative pathway to initiate symbioses, where a purine derivative may play a key role in triggering nodule formation. 相似文献
102.
Verwilghen DR Martens A Busschers E Franck T Deberg M Henrotin Y Vanderheyden L Serteyn D 《Veterinary research communications》2011,35(7):401-408
The measurement of biomarkers that reflect cartilage breakdown is a powerful tool for investigating joint damage caused by
disease or injury. Particularly in cases of osteochondrosis, synovial concentrations of these biomarkers may reveal the presence
of osteoarthritic changes. Coll2-1, Coll2-1 NO2 and myeloperoxidase have recently been introduced in equine osteoarticular research but comparison between the concentrations
of these markers in OCD affected and healthy joints has not been made. Therefore, this study aimed at reporting the synovial
concentrations of these biomarkers in joints affected with osteochondral fragments in the tarsocrural joint compared to unaffected
joints. Myeloperoxidase and Coll2-1NO2 revealed to have similar levels between affected joints and controls. However, in contrast to previous studies using C2C
the present study demonstrated that synovial levels of Coll2-1 were significantly elevated in tarsocrural joints affected
with osteochondrosis. Thus, Coll2-1 may be an earlier marker of cartilage degeneration than other cartilage degradation markers
that have been previously used in equine medicine. 相似文献
103.
Sophie Y. Dillen Romain Monclus Cécile Barbaroux Catherine Bastien Reinhart Ceulemans Erwin Dreyer Marc Villar Franck Brignolas Nicolas Marron 《Annals of Forest Science》2011,68(7):1265-1275
Introduction
Because of its vigorous growth, poplar can play an important role for sustainable production of woody biomass to cover renewable energy needs. Hence, the selection of suitable genotypes has to be based on relevant traits, among which intrinsic water use efficiency (W i, estimated through leaf carbon isotope discrimination, Δ) may be a key trait. Besides a large genetic variation in Δ among the frequently planted poplar hybrids, the use of Δ in deployment or breeding programmes requires insights in the robustness of the genotype ranking for Δ across environments and years. 相似文献104.
Nizak C Monier S del Nery E Moutel S Goud B Perez F 《Science (New York, N.Y.)》2003,300(5621):984-987
Here we report an approach, based on antibody phage display, to generate molecular conformation sensors. Recombinant antibodies specific to the guanosine triphosphate (GTP)-bound conformation of the small guanosine triphosphatase (GTPase) Rab6, a regulator of membrane traffic, were generated and used to locate Rab6.GTP in fixed cells, and, after green fluorescent protein (GFP) tagging and intracellular expression, to follow Rab6.GTP in vivo. Rab6 was in its GTP-bound conformation on the Golgi apparatus and transport intermediates, and the geometry of transport intermediates was modulated by Rab6 activity. More generally, the same approach could be applied to other molecules that can be locked in a particular conformation in vitro. 相似文献
105.
M Templin A Franck Du Chesne A H Leist Y Zhang R Ulrich V Schadler U Wiesner 《Science (New York, N.Y.)》1997,278(5344):1795-1798
Organically modified aluminosilicate mesostructures were synthesized from two metal alkoxides with the use of poly(isoprene-b-ethyleneoxide) block copolymers (PI-b-PEO) as the structure-directing molecules. By increasing the fraction of the inorganic precursors with respect to the polymer, morphologies expected from the phase diagrams of diblock copolymers were obtained. The length scale of the microstructures and the state of alignment were varied using concepts known from the study of block copolymers. These results suggest that the use of higher molecular weight block copolymer mesophases instead of conventional low-molecular weight surfactants may provide a simple, easily controlled pathway for the preparation of various silica-type mesostructures that extends the accessible length scale of these structures by about an order of magnitude. 相似文献
106.
107.
108.
Franck Rivano Malena Martinez Victor Cevallos Christian Cilas 《European journal of plant pathology / European Foundation for Plant Pathology》2010,126(4):541-552
Resistance of rubber tree clones to South American Leaf Blight (SALB) caused by the fungus Microcyclus ulei is normally assessed in specific large-scale clone trials, which in general entail a considerable amount of work. Four variables
are observed monthly on each tree over many years: disease severity and conidial sporulation intensity on young leaves, and
severity and stroma density on mature leaves. In order to simplify this field assessment method, we tested the resistance
of eight rubber tree clones to M. ulei in Ecuador in a Fisher block design with four replicates per treatment. Three months after planting, monthly observations
were made for a period of 12 months on the foliage focusing on the four variables, in order to quantify disease development.
Given the correlations between the four variables, assessment of conidial sporulation intensity on young leaves and stroma
density on mature leaves should be sufficient. The most suitable period to start the assessment was 6 months after planting,
for a duration of six to nine months. As repeated observations on the same trees were autocorrelated, it was possible to reduce
the assessment frequency to once every 2 months. To conclude, assessing the resistance of rubber tree clones to SALB in large-scale
clone trials can be optimized to reduce the number of observation times by 50%. 相似文献
109.
110.
Marie-Pier Boutin Franck J. Ollivier 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(10):1064
A 9-year-old castrated male pitbull dog was presented for evaluation of a subconjunctival swelling of 10 days duration. On ophthalmic examination, a subcutaneous mass was identified at the right lateral canthus. An excisional biopsy was performed, and histopathological analysis confirmed a diagnosis of a subcutaneous fibroma. Eleven months after surgical excision, the dog had no evidence of recurrence. Fibroma should be included in the differential diagnosis of rapidly enlarging eyelid masses. 相似文献