Growth characteristics and lipid distribution in two lines of chicken selected for low or high abdominal fat

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Trigeminal neuralgia

AbstractTwo different clinical entities, essential or secondary neuralgia, are associated with different pathologies. The pathways of CN V comprise the cervical spine, the brainstem, the root of the nerve and the three peripheral branches: V1, V2 and V3. The lesions responsible for neuralgia are neoplastic, vascular, inflammatory, malformative or post-traumatic. The examination protocol should explore the set of CN V pathways. Neurovascular compression is the main cause of essential neuralgia. It is investigated by T2-weighted inframillimetric volume. Two conditions are necessary to diagnose a neurovascular compression: localised on the root entry zone [(REZ), 2–6mm from the emergence of the pons] and perpendicularly. In the absence of neurovascular compression, thin slices and a gadolinium injection are necessary

Etude phénologique des paramètres lies a la reproduction des mésanges en futaie de chênes

L’étude pliénologique des paramètres température, débourre ment des arbres, apparition des chenilles dans la canopée, ponte et nourrissage des Mésanges ( Parus major et Parus caeruleus), dans quatre milieux de futaie régulière de chênaie de plaine, d’âges variés (18, 23, 90 et 200 ans), a permis de dégager les conclu sions suivantes : Il existe des variations microclimatiques au sein du massif forestier, entre les parcelles d’âges différents : les milieux jeunes à végétation basse, sont plus froids au printemps que les futaies âgées ; en particulier les gelées matinales n’y sont pas exception nelles. De plus, ces milieux jeunes sont soumis à des variations journalières importantes. Les arbres (Chênes, Charmes, Hêtres) débourrent plus tôt dans les futaies âgées (90 et 200 ans), puis dans les jeunes parcelles (18 et 23 ans). Les zones étendues de semis sont très nettement en retard. Ce phénomène est bien corrélé à la température du sol à — 20 cm et non directement avec l’âge des arbres. De la même fa çon les chenilles apparaissent plus tôt en futaie mûre et les mé sanges y commencent leur cycle de reproduction avant celles des milieux plus jeunes. Ces phénomènes sont tout à fait parallèles à ceux observés les différentes années dans un milieu donné, où la température moyenne du printemps conditionne de la même façon les phénolo- gies de feuillaison, d’éclosion des chenilles et de reproduction des Mésanges. Il s’ensuit une concordance entre l’apparition des feuilles aux arbres et l’éclosion des chenilles, puis entre le maximum d’abon dance de ces chenilles et la période de nourrissage des poussins de mésanges. Cette synchronisation, nécessaire à leur survie, a pu être sélectionnée au fil des différentes années lors des variations climatiques ; mais elle se manifeste encore chaque année entre des milieux voisins à microclimats différents.In four successional stages of a lowland oak forest, the fol lowing phenological parameters were assessed : temperature, lea fing time of the trees, appearance of caterpillars in the canopy, laying of eggs and feeding period of young by two species of tits, Parus major and P. caeruleus. The microclimate differs between the early and the late suc cessional stages of the same forest : early stands with low vegeta tion are colder in spring than the old timber stands, with more frequent morning frosts ; moreover, the young stages show wider daily variations of temperature. The trees (Oak, Beech, Hornbeam) come into leaf later in the young timber (18 and 23 year old) than in the old (90 and 200 year old). This delay is correlated with the soil temperature (at — 20 cm) but not directly with the age of the trees In the same way, the leaf caterpillars appear earlier and the tits begin their breeding cycle earlier in the old stands than they do in the young stands. Between different years, in a given habitat, the same phenolo gical timing was recorded. The mean temperature of early spring determines the dates of tree leafing, caterpillar appearance, and reproduction of the titmice. Finally, there is a good correlation between the appearance of leaves on the trees and the hatching of caterpillars, and between the maximum abundance of caterpillars and the time when tits feed their young. Being of obvious survival value, it may be assumed that such a co-evolution took place during the pleistocene climatic changes ; however, local adaptations to the microclimates of adjacent habi tats have to be made on a yearly basis

Croissance et caractéristiques de carcasse de poulets sélectionnés en lignées divergentes soit sur la vitesse de croissance soit sur l'état d'engraissement

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Activation by SLAM Family Receptors Contributes to NK Cell Mediated "Missing-Self" Recognition.

Natural Killer (NK) cells attack normal hematopoietic cells that do not express inhibitory MHC class I (MHC-I) molecules, but the ligands that activate NK cells remain incompletely defined. Here we show that the expression of the Signaling Lymphocyte Activation Molecule (SLAM) family members CD48 and Ly9 (CD229) by MHC-I-deficient tumor cells significantly contributes to NK cell activation. When NK cells develop in the presence of T cells or B cells that lack inhibitory MHC-I but express activating CD48 and Ly9 ligands, the NK cells' ability to respond to MHC-I-deficient tumor cells is severely compromised. In this situation, NK cells express normal levels of the corresponding activation receptors 2B4 (CD244) and Ly9 but these receptors are non-functional. This provides a partial explanation for the tolerance of NK cells to MHC-I-deficient cells in vivo. Activating signaling via 2B4 is restored when MHC-I-deficient T cells are removed, indicating that interactions with MHC-I-deficient T cells dominantly, but not permanently, impair the function of the 2B4 NK cell activation receptor. These data identify an important role of SLAM family receptors for NK cell mediated "missing-self" reactivity and suggest that NK cell tolerance in MHC-I mosaic mice is in part explained by an acquired dysfunction of SLAM family receptors

Effets de la restriction alimentaire pendant la période de croissance sur les performances des reproductrices naines

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Spin Glass Ordering in Diluted Magnetic Semiconductors: a Monte Carlo Study

We study the temperature-dilution phase diagram of a site-diluted Heisenberg antiferromagnet on a fcc lattice, with and without the Dzyaloshinskii-Moriya anisotropic term, fixed to realistic microscopic parameters for $IIB_{1-x} Mn_x Te$ (IIB=Cd, Hg, Zn). We show that the dipolar Dzyaloshinskii-Moriya anisotropy induces a finite-temperature phase transition to a spin glass phase, at dilutions larger than 80%. The resulting probability distribution of the order parameter P(q) is similar to the one found in the cubic lattice Edwards-Anderson Ising model. The critical exponents undergo large finite size corrections, but tend to values similar to the ones of the Edwards-Anderson-Ising model.Comment: 4 pages plus 3 postscript figure