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Béatrice Drouet Luis Garcia Dominique Simon-Chazottes Marie Geneviève Mattei Jean-Louis Guénet Arnold Schwartz Gyula Varadi Martine Pinçon-Raymond 《Mammalian genome》1993,4(9):499-503
Using both chromosomal in situ hybridization and molecular techniques, we report the genetic localization of the gene coding for the alpha 1 subunit of the skeletal slow Ca2+ current channel/DHP receptor gene (Cchl1a3) on human Chromosome (Chr) 1 (1q31–1q32 region) and on mouse Chr 1 region (F-G). On the basis of single-strand conformation polymorphism (SSCP-PCR) analysis in an interspecific backcross, we have determined that the Cchl1a3=mdg (muscular dysgenesis) locus is very closely linked to the myogenin (Myog) locus. 相似文献
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Nathalie Doerflinger Catherine Linder Karim Ouahchi Gabor Gyapay Jean Weissenbach Denis Le Paslier Philippe Rigault Samir Belal Christiane Ben Hamida Faycal Hentati Mongi Ben Hamida Massimo Pandolfo Stephano DiDonato Ronald Sokol Herbert Kayden Pierre Landrieu Alexandra Durr Alexis Brice Fran?oise Goutières Alfried Kohlschütter Pascal Sabouraud Ali Benomar Mohamed Yahyaoui Jean-Louis Mandel Michel Koenig 《American journal of human genetics》1995,56(5):1116-1124
Ataxia with vitamin E deficiency (AVED) is an autosomal recessive disease characterized clinically by neurological symptoms with often striking resemblance to those of Friedreich ataxia. This disorder has been reported previously as familial isolated vitamin E deficiency. We have mapped recently the AVED locus to a 5-cM confidence interval on chromosome 8q by homozygosity mapping in six Mediterranean families. We have now analyzed six new and two previously described families and demonstrate genetic homogeneity despite important clinical variability and wide geographic origins. Analysis of nine new tightly linked microsatellite markers, including four characterized in this study, revealed a predominant but not unique mutation in northern African populations, where this condition is more frequent. Haplotype analysis but also classical recombinations allowed us to refine the AVED position to a 1-cM interval. A YAC contig over this interval was constructed from marker STSs and YAC fingerprint data, in order to facilitate the search of the AVED gene. 相似文献
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Bertrand Dommée Andrée Biascamano Nicole Denelle Jean-Louis Bompar John D. Thompson 《American journal of botany》1995,82(6):734-740
Natural populations of Thymelaea hirsuta have previously been shown to comprise four distinct sexual morphs: males, females, protogynous individuals, i.e., first female then male, and protandrous individuals, i.e., first male then female. The objective of the present study has been to confirm the genetic basis of this sexual tetramorphism by quantifying morph ratios in the open-pollinated progeny of the four sexual phenotypes growing in a natural population. All four phenotypes were recovered in the progeny of each morph. All observed plants displayed a single sexual phenotype, thus confirming the genetic basis of the tetramorphism. The progeny sex ratios indicate that the genetic determination of sex in this species may be influenced by cytoplasmic factors, while the observed levels of functional female fertility suggest a near-dioecious system. The evolutionary significance of this tetramorphism as a transitional stage in the evolution of dioecy is discussed. 相似文献
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Luc Cynober Jean-Louis Auget Jean Agneray Ohvanesse G. Ekindjian 《Biochemical and biophysical research communications》1984,123(2):535-542
2-deoxyglucose uptake rates at low sugar concentrations (less than 500 μM) appeared to be lower than those predicted by the Michaelis-Menten model which correctly described higher concentrations. This phenomenon which we will call concentration-dependent transport lag, was also observed for L-glucose uptake which suggest that this phenomenon is carrier-independent. A model involving the perimembrane space is developed which, for L-glucose, gives k1 = 0.931 ± 0.072 × 10?6 l. mg protein?1. minute?1, k2 = 2.97 ± 0.19 × 10?7 l. mg protein?1. minute?1 and So = 88,8 ± 4,3 μM; where k1 is the diffusion constant in the cell membrane, k2 is the diffusion constant in the perimembrane space and So the sugar concentration required in the external medium in order to provide an équivalent sugar concentration in the transport carrier area. 相似文献
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R. Senelar J. P. Bureau A. Serre D. A. Theunynck B. Serrou 《Cancer immunology, immunotherapy : CII》1977,3(1):15-22
Summary The thymic and splenic reactions, following injections of BCG and living Brucella M. in the guinea pigs, were studied. Both microorganisms injected intravenously produced thymic involution, maximal after BCG inoculation, followed by regeneration that was complete by day 10 in Brucella M.-treated guinea pigs, and by day 15, in BCG injected guinea pigs. Increase of mitotic index was more accentuated and more persistent after Brucella M. than after BCG treatment in the thymus. After a short involution period the spleen of injected animals increased in size in both groups. The splenic enlargement was dramatic and occurred at an accelerated rate in animals given BCG. It appeared to be the result of a conspicuous involvement of the red pulp by multiple granulomas. In Brucella M. treated guinea pigs the splenic enlargement was less obvious, but the splenic white pulp was more abundant in BCG-treated guinea pigs. Granulomas were observed only in the periarterial sheaths of the white pulp.These observations provide evidence for the hypothesis that injections of both BCG and Brucella M. provoke a proliferation of B and T lymphocytes, a migration of T lymphocytes from the thymus to the T-dependent area of the spleen which seems, perhaps, more marked after injection of Brucella M., and a strong granulomatous histiocytic reaction which is more conspicuous in animals given BCG. 相似文献
30.
Mohamed Saïd Hifnawy Jacqueline Vaquette Thierry Sévenet Jean-Louis Pousset André Cavé 《Phytochemistry》1977,16(7):1035-1039
Stems and leaves of Myrtopsis macrocarpa, M. myrtoidea, M. novae-caledoniae and M. sellingii yielded terpenes, sterols, coumarins, alkaloids (furoquinolines and quinolones) and amides. A new quinolone (8-methoxy flindersine) occurs in Myrtopsis macrocarpa, a new amide (N-benzoyltryptamine) in M. myrtoidea, two new coumarins (myrsellin and myrsellinol) and a new dihydrofuroquinoline (myrtopsine) in M. sellingii. Structures of the new compounds are proposed from chemical and spectroscopic evidence. 相似文献