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Didier Merle 《Geobios》2005,38(4):505
Jsowerbya, nov. gen. (Gastropoda: Muricidae) includes three species from the Eocene of the Paris and Hampshire basins. It increases the number of extinct muricid genera, which curiously represent a very small fraction of the described genera. The species of Jsowerbya, often mistaken for the muricopsine genus Muricopsis, possess a unique combination of characters shared with the subfamilies Ocenebrinae and Ergalataxinae. A cladistic analysis, based on structural homologies of the spiral sculpture, however, suggests that Jsowerbya is closely related to the Ocenebrinae. Thus, Jsowerbya is here regarded as one the most basal Ocenebrinae. 相似文献
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Didier Arseguel Armand Lattes Michel Baboul ne 《Biocatalysis and Biotransformation》1990,3(3):217-225
Horseradish peroxidase was chemically conjugated on its carbohydrate moieties with short aliphatic chains (C8 and C16). An analytical method using FT.IR spectroscopy was developed to analyze this alteration in enzyme structure. This method is non-destructive, and can be applied directly to samples of the reaction mixture. More general applications of this technique are described and discussed. 相似文献
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Didier Rognan 《Journal of Physiology》2006,99(2-3):232-244
The concomitant development of in silico screening technologies and of three-dimensional information on therapeutically relevant macromolecular targets makes it possible to navigate in the structural proteome and to identify targets fulfilling user-defined queries. This review illustrates some in-house recent advances in the development of target libraries and how they can be browsed to unravel chemogenomic information. 相似文献
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Making use of a newly designed mobilizable suicide vector, the genetic determinants encoding Shigella sonnei lipopolysaccharide (LPS) were stably integrated into the chromosome of the live attenuated Vibrio cholerae vaccine strain CVD103-HgR. Expression studies showed that the production of complete S. sonnei O-polysaccharide (O-PS)-bearing LPS was limited in bivalent recombinant strains that were also proficient in the synthesis of the host-encoded Inaba O-PS. Conversely, high amounts of LPS carrying S. sonnei O-PS are produced in monovalent Inaba-deficient derivatives, even in those strains which do not co-express the compatible R1 LPS core. Thus, the non-enterobacterial V. cholerae LPS core efficiently acts as a receptor for covalent binding of S. sonnei O-PS provided that competition with the host O-PS is avoided. Expression of the R1 core interferes with cell division in recombinant V. cholerae without affecting other physiological properties of vaccine strain CVD103-HgR. Both monovalent and bivalent strains stimulated high serum-antibody titres specific for their respective O-serotype(s) when administered to rabbits. The potential of V. cholerae as an expression carrier for heterologous O-serotypes is discussed. 相似文献
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Eric Moulton Mélika Amor-Sahli Vincent Perlbarg Christine Pires Sophie Crozier Damien Galanaud Romain Valabregue Marion Yger Flore Baronnet-Chauvet Yves Samson Didier Dormont Charlotte Rosso 《PloS one》2015,10(11)
Fractional anisotropy (FA) is an effective marker of motor outcome at the chronic stage of stroke yet proves to be less efficient at early time points. This study aims to determine which diffusion metric in which location is the best marker of long-term stroke outcome after thrombolysis with diffusion tensor imaging (DTI) at 24 hours post-stroke. Twenty-eight thrombolyzed patients underwent DTI at 24 hours post-stroke onset. Ipsilesional and contralesional FA, mean (MD), axial (AD), and radial (RD) diffusivities values were calculated in different Regions-of-Interest (ROIs): (1) the white matter underlying the precentral gyrus (M1), (2) the corona radiata (CoRad), (3) the posterior limb of the internal capsule (PLIC) and (4) the cerebral peduncles (CP). NIHSS scores were acquired at admission, day 1, and day 7; modified Rankin Scores (mRS) at 3 months. Significant decreases were found in FA, MD, and AD of the ipsilesional CoRad and M1. MD and AD were also significantly lower in the PLIC. The ratio of ipsi and contralesional AD of the CoRad (CoRad-rAD) was the strongest diffusion parameter correlated with motor NIHSS scores on day 7 and with the mRS at 3 months. A Receiver-Operator Curve analysis yielded a model for the CoRad-rAD to predict good outcome based on upper limb NIHSS motor scores and mRS with high specificity and sensitivity. FA values were not correlated with clinical outcome. In conclusion, axial diffusivity of the CoRad from clinical DTI at 24 hours post-stroke is the most appropriate diffusion metric for quantifying stroke damage to predict outcome, suggesting the importance of early axonal damage. 相似文献
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Guiraud JP Bourgi J Stervinou M Claisse M Galzy P 《Biotechnology and bioengineering》1987,29(7):850-858
A respiratory-deficient, mutant of Kluyveromyces fragilis was isolated using a ethidium bromide mutagenesis. It was characterized by a loss of cytochromes a + a3 and by an improvement of its inulinase activity. Under anaerobic conditions this mutant was always better than the wild strain for ethanol production especially from Jerusalem artichoke extracts containing large amounts of high polyfructosans ("early" extracts). 相似文献