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The Spanish ``Asturiana' cattle breed is characterized by the segregation of a genetically determined muscular hypertrophy
referred to as double-muscling or ``culones'. We demonstrate by linkage analysis that this muscular hypertrophy involves
the mh locus previously shown to cause double-muscling in the Belgian Blue cattle breed, pointing towards locus homogeneity of this
trait across both breeds. Moreover, using a twopoint and multipoint maximum likelihood approach, we show that flanking microsatellite
markers are in linkage disequilibrium with the mh locus in both breeds albeit with different alleles. Finally, we discuss how allelic homogeneity across breeds might be exploited
to achieve efficient genetic fine-mapping of the mh locus.
Received: 13 September 1996 / Accepted: 20 January 1997 相似文献
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Histidine-containing protein, HPr, of the Escherichia coli phosphoenolpyruvate:sugar phosphotransferase system has an active site that involves His-15, which is phosphorylated to form a N delta 1-P-histidine, Arg-17, and the carboxy-terminal residue Glu-85. Mutant HPrs with alterations to the three C-terminal residues, Glu-85, Leu-84, and Glu-83, were produced by site-directed mutagenesis. The properties of these mutants were assessed by kinetic analysis of enzyme I, enzyme IImannose, enzyme IIN-acetylglucosamine, and enzyme IImannitol, and the phosphohydrolysis properties of the HPr mutants. The results show that it is the C-terminal alpha-carboxyl of Glu-85 that is involved in the active site, and this involvement may be restricted to the phosphoryl donor action of HPr. The contribution of this alpha-carboxyl group is modest as the deletion of Glu-85 resulted in the reduction of the enzyme II activity (kcat/Km) to about 33%. Removal of both Glu-85 and Leu-84 yields an HPr that is an impaired substrate of both the enzyme I and enzyme II reactions. Glu-83 appears to have no role in the active site. 相似文献
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J Emerit C Jeny I Emerit P Le Hoang O L Caen S Pelletier M Mollet F Congy 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1986,302(7):243-246
Neutrophils of patients with Beh?et's syndrome generate increased amounts of oxygen free radicals. This phenomenon is inhibited by superoxide dismutase (SOD) and catalase and is implicated in vasculitis. We treated seven patients with active Beh?et's syndrome by CuZn SOD intramuscularis with dramatic improvement of clinical symptoms. 相似文献
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Georges Lantéri-Laura 《PSN》2003,1(3):39-47
The author describes the history of the concept of depression in modern psychiatry from the end of the Age of Enlightenment until today in three parts. In the first period (1793–1854), the opposition of general delusion (mania) and partial delusion (melancholia) prevails, without the problem of changes of the affective state being an issue. Only with the work of J. Guislain, and later of W. Griesinger, does the concept of mood disorders become a categorical form in mental pathology with the idea of psychological pain. The second period (1854–1926) is distinguished firstly by the works of J.P. Falret on circular insanity, and then those of V. Magnan, J. Ségnan, J. Séglas et Ph. Chaslin in France and E. Kraepelin in Germany. This period is characterized by the classical construction of periodic manicdepressive psychosis and takes into account the opposition of mania and melancholia. In the third period (1926–1977), the influences of phenomenology, psychoanalysis and structuralism predominate. Gradually melancholia loses its place at the core of this field, in favour of the concept of depression and this change now characterizes contemporary psychiatry. 相似文献
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Marc Ledig Adam Holownia Jean-Christophe Copin Georges Tholey Irina Anokhina 《Neurochemical research》1996,21(3):313-317
The aim of this work was to investigate the effect of supplementation of a maternal alcohol diet with a grape extract on glial
cell development. Glial cells were cultured during 4 weeks from cortical brain cells of the new born offspring in DMEM medium
supplemented with fetal calf serum. Enzymatic markers of nerve cell development were measured (enolase isoenzymes and glutamine
synthetase). Since alcohol consumption produces free radicals the antioxidant system superoxide dismutase was also investigated.
Compared to the decrease found in only alcohol treated animals, all parameters except neuron-specific enolase were antagonized
and even stimulated after grape extract supplementation. The effect was more important after only 1 month than 3 months of
treatment. Also in the total brain an alcohol antagonizing effect and a glutamine synthetase activation were found. Our data
demonstrate that addition of a grape extract to the maternal alcohol diet may partially or completely overcome the alcohol
induced retardation of glial cell development. 相似文献