The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
For durum wheat, we promote the use of carbon isotope discrimination (Δ) as an indirect selection criterion for transpiration efficiency and grain yield (GY), and we identify the most effective organ for characterising Δ genotypic variation. A field experiment was conducted in the South of France on 144 accessions, with a drought period occurring from February to June. Harvest index (HI), GY and Δ...
La superposition procruste est bien adaptée à l’étude des hétérochronies en biologie évolutive. (1) La méthode procruste donne une définition précise et mathématique de deux des trois variables de l’hétérochronie : la taille et la conformation. (2) Elle permet de décrire les structures globalement, et donc d’analyser les morphologies dans leur ensemble et non plus trait par trait comme dans les méthodes...
Trois types d’humus, représentatifs de la biodiversité écosystémique des Alpes internes, un dysmull sous Pinus sylvestris, un oligomull sous Abies alba et un mor sous Pinus cembra, sont étudiés, par un suivi de la production et du prélèvement de l’azote minéral et par une caractérisation de la pédofaune. Seul le fonctionnement de l’oligomull s’apparente à celui d’un mull, par une production et des...
In 1993, several horns of an unknown mammal were collected in the south of Vietnam. Due to the unusual characteristics of its horns, the ‘linh duong’, as named by Vietnamese hunters, was quickly described as belonging to a new monospecific genus of bovid, i.e. Pseudonovibos spiralis Peter & Feiler, 1994. The taxonomic status of Pseudonovibos was a highly controversial subject, and it has been...
During the G1/S transition of the cell cycle variations in the labelling by 8-N 3 -[ 32 P]cAMP of the protein kinase A regulatory subunits RI and RII, used as a probe to monitor post-translational modifications that may regulate cAMP binding, were observed in synchronized HeLa cells. A decrease in 8-N 3 -[ 32 P]cAMP labelling of RI, RII and RII phosphorylated by the...
Les mammifères présentent un système de détermination chromosomique du sexe où les mâles sont hétérogamétiques (femelles XX/mâles XY). Des études comparatives des gènes présents sur les chromosomes sexuels des mammifères euthériens ont révélé que la plupart des gènes du chromosome Y possèdent des homologues sur le chromosome X. Ces observations, ainsi que la présence de deux régions homologues (régions...
La disponibilité du monoxyde d’azote (NO) produit par l’endothélium vasculaire est régulée par les métaux de transition mais leur mécanisme d’action reste à définir. La concentration locale de NO a été mesurée à la surface de cellules endothéliales de veine de cordons ombilicaux humains, en culture, stimulées par l’histamine ou la thrombine en présence de chélateurs, par ampérométrie différentielle...
This study describes the noradrenergic modulation of tactile afferent information in the sensorimotor cortex of urethane-anesthetized rats. Synaptic and spike responses to a mechanical stimulation of the hand palm were evaluated by means of current source-density analysis and unit activity recording in all cortical layers. Results showed that activation of the locus coeruleus decreased and shortened...
In 1993, the discovery of several pairs of lyre-shaped horns with corrugations was recorded in Vietnam and regarded as evidence for a new, large bovid, later referred to as Pseudonovibos spiralis Peter & Feiler, 1994. Despite numerous field investigations made since 1994 in Vietnam and Cambodia, no new anatomical evidence has ever been found, except for two frontlets with their horn cores and...
Le cobaye adopte une configuration squelettique tout aussi stéréotypée pendant le repos qu’au cours de la locomotion. Dans le premier cas, le segment cervical de la colonne vertébrale affecte une forme en S et est orientée verticalement. Dans le second, ce segment est porté parallèlement au support sur lequel le cobaye progresse. Ces résultats confortent l’hypothèse que le contrôle de la posture...
Association study is the method of choice to identify genes involved in complex processes that result from the interaction of environmental and genetic factors. However, because of biases that increase the risk of false positive reports, preliminary positive conclusions have to be reproduced on other populations to be validated as firm conclusions. In 1994, certain alleles of two genes, APOE (Apolipoprotein...
Bothriocephalid (Diphyllobothrium pacificum) and Ascarid (Ascaris lumbricoides) eggs have been identified in a sample taken in the abdominal cavity of a child skeleton found in Zeto Point (ADK-011), an archaeological site on Adak Island in the Central Aleutian Islands (Alaska).
By analogy with the immune defence system, the existence is suggested of a chemo-defence system protecting living organisms against toxic substances, whether natural or man-made, that are present in the environment. This paper deals first with the various facets of such a system: mechanisms involving, among others, lipophilic compounds, hydrophilic compounds, oxidants, acidosis, genotoxics and metals;...
Lake Valencia is located in the centre of the endemic area of the intestinal schistosimiasis in Venezuela. The dominance of two pulmonate species, Biomphalaria glabrata and B.<space>prona., was observed in the lake. Both species are strongly associated with two distinct types of habitats suggesting that competition is occurring between these two species. B.<space>glabrata and B.<space>prona...
Le but de ce travail est d'analyser la morphogenese de la ceinture pelvienne foetale, de definir les reperes radiographiques normaux en fonction de l'age gestationnel et du sexe pour etablir un referentiel. Un echantillon homogene de 500 radiographies de bassin de face de foetus a ete etudie. Des mesures radiographiques (largeur du bassin<space>; distances inter-epines iliaques postero-inferieures,...
La morphologie des inflorescences, et celle des fleurs d'Atriplex halimus, ont jusqu'ici fait l'objet de descriptions incompletes. Cette espece a ete consideree comme monoique ou dioique. Une etude ontogenique et des observations repetees ont permis de mettre en evidence des types floraux, morphologiquement et fonctionnellement hermaphrodites, jamais decrits jusqu'a present. Chez cette espece, un...
We previously showed that highly metastatic clones derived from the poorly metastatic human melanoma cell line M4Be are very radiosensitive provided that they are deficient in complex gangliosides. Here, we report that the highly metastatic clone 4 appears more sensitive to activated adherent leukocytes than M4Be via a transmembrane TNF-α-dependent mechanism. Adherent leukocytes (AL) were freshly...
Sex determination in the order Hymenoptera is based on arrhenotoky, hymenopteran males are usually haploid and females diploid. Males of the Ichneumonidae Diadromus pulchellus, solitary endoparasitoid of A Acrolepiopsis assectella pupae, are normally haploid, but diploid males are present in a natural population and can be obtained in an experimental population. The future of an ovocyte laid by mated...
The vegetation and physical and chemical characteristics of the water and sediment in ten temporary pools submitted to various anthropogenic disturbance were studied in Morocco over two hydrological cycles (1997-1998 and 1998-1999). Results of multivariate and parametric analyses show that disturbance has a significant impact on water and sediment. Agriculture in the catchment resulted in higher levels...
L'analyse pollinique d'une sequence sedimentaire (5,50 m) d'un petit lac (15<space>m<space>x<space>25<space>m) de l'etage subalpin (2 020 m) de moyenne Maurienne met en evidence l'existence d'un peuplement d'erables a 2 020 m d'altitude dans le domaine interne des Alpes francaises pendant plus de 2 500 ans. Trois dates AMS de macrorestes vegetaux terrestres etayent la chronologie...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.