Convergence des référentiels de qualité et implications pour la fonction technique biomédicale

Risk management in the hospital, which is one of the referentiels of the ANAES accreditation manual, may be considered on two levels. Firstly, risk management may be approached globally, in the same way as it is tackled in the accreditation process. Secondly, risk management may be more definite. A specific risk chosen in accordance with the priorities of a particular plan may be dealt with individually. In this respect, the tranfusion process allows the risk management method to be tested and developed.

Mise en évidence d''une fonction excrétrice de la peau chez certains cétacés odontocètes et mysticètes

Up to the present there was not believed to be any excretion in the skin of cetaceans because of the absence of sweat and sebaceous glands. It has now been shown that concentrated salty excretion is produced in various cetaceans by numerous epidermal cells dispersed in the whole epidermis. They are not aggregated into glands. Other epidermal cells, likewise scattered in the epidermis, synthetize lipids; this function seems homologous to the sebaceous function of other mammals.     

Effet de la longueur d'onde de préillumination sur la désactivation des formes oxydées du donneur d'électrons du Photosystème II

Effect of preillumination wavelength on the deactivation of oxidized forms of the Photosystem II electron donor

Deactivation was studied using chlorella cells or spinach chloroplasts after an illumination of different wavelengths (light I = 710 nm, light II = 650 or 480 nm). The measurements concerned mainly the third oxidized state S₃ of the System II electron donor, according to the scheme proposed by

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, (Photochem. Photobiol., 11 (1970)457). The time course of deactivation was followed during the dark after each preillumination. Different results were obtained with algae in state 1 or state 2 as defined by

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, (Biochim. Biophys. Acta, 189 (1969) 366). In state 1 the deactivation of S₃ is faster after light 11 than after light 1; in state 2, except at the beginning of the decay, the deactivation of S₃ is almost the same after the two kinds of preillumination. With chloroplasts the deactivation is slower, but always faster after light II than after light I, no transition between state 1 and state 2 was observed. The results are discussed with reference to the possible reducing substrates of the reaction.     

Variation du taux d'acide abscissique chez deux variétés de poiriers, la Passe-Crassane et la Doyenne du Comice, en fonction de l'induction de la parthénocarpie par l'acide gibbérellique

The content of abscisic acid in the developing fruits of two cultivars of pear (Pyrus communis L.) was determined by UV spectrophotometry and by a colorimetric method based on the possibility of the lactone corresponding to abscisic acid to give a purple colour when sodium hydroxide is added. The young fruits were harvested either from trees treated with gibberellic acid (GA₃), for the purpose of inducing parthenocarpy, or from untreated trees. High levels of abscisic acid were associated with abortion and abscission of young fruits (June drop). There was little difference between fruits of GA₃-treated and untreated trees of the cultivar Passe-Crassane. In the other cultivar, ‘Doyenne du Comice’, the level of abscisic acid in the fruits of GA₃-treated trees was about twice as high as in control fruits and seemed to be directly related to the number of fruits per tree.     

Étude polarographique de la mobilisation du fer de la ferritine

Polarographic study of the mobilization of ferritin ironPolarographic study allows to propose a model for mobilization of ferritin iron: an equilibrium exists between iron core and small quantities of iron outside the protein.These iron atoms would be lying on electron acceptor sites including SH groups. The number of sites is dependent on iron content of ferritin.Therefore, the iron could be removed by the action of reducing agents such as xanthine oxidase or ascorbic acid, and then chelated by a complexing agent.     

Régulation de la synthèse du DNA dans la glande séricigène de Bombyx mori: II. Etude de l''activité DNA-polymérasique présente dans la fraction soluble brute

In the silkglands of Bombyx mori larvae, DNA synthesis suddenly stops in the middle of the fifth larval instar, when cellular growth is over and cell activity is turned on to massive silk synthesis. Of much interest is to determine what factors are implied in the quantitative and temporal control of DNA synthesis in this tissue.Previous work on thymidine metabolism in the intact organ lead us to look for several enzymatic activities in the soluble fraction of the cells during this period.The results presented here concern the kinases of the thymidylic pathway. As measured in vitro from crude cellular extracts, thymidine-kinase is present at a lower level than thymidylate-kinase but both activities vary in connection with the pattern of in situ DNA synthesis, reaching their highest levels on the fourth day of the instar and decreasing as DNA synthesis definitively stops in the glands.     

Biosynthèse de la cellulose bacterienne deutériée: étude par R. M. N. du taux d'incorporation et de la localisation du deutérium

The use of the NMR spectra (250 MHz) of cellulose triacetate allows the determination of the percentage of deuterium bonded to each of the six carbon atoms of the monomer residue (except for H_?1 and one of the protons bonded to C₆ where the signals overlap). Deuterated derivatives of D -glucose and/or deuterated water were used for the biosynthesis of bacterial cellulose by Acetobacter xylinum. Analysis of NMR spectra of acetylated samples gives the following results. About 90% of the protons linked to C₁ and C₆ come from the D -glucose used in the nutrition medium, whereas 10% are exchanged with other sources of protons. Over 40% of the protons linked to C₂, C₃, C₄, and C₅ arise from the water of the nutrition medium. Discrepancies between results of biosynthesis from deuterated water and from deuterated D -glucose can only be explained if more than one enzymatic process is involved in the biosynthesis of bacterial cellulose.     

Groupement et ordination appliqués à l''étude de la répartition de l''épifaune benthique de l''estuaire maritime et du Golfe du Saint-Laurent

Forty-seven navigation buoys were used to collect quantitative samples of epibenthic fauna in the Lower Estuary and Gulf of St. Lawrence. Stations, as described by their sessile species and biomass composition, were grouped using multivariate analysis. A Gower similarity index, modified to take into account the importance of each species in the ecosystem, was used to compare stations. Results obtained by cluster and principal coordinate analyses showed comparable relations between stations. North Shore and Gaspé Coast stations were separated from those of the Lower North Shore, the Mingan Island sector and the Lower Estuary. Stations from the Lower North Shore were also separated from those of the Mingan Island region and of the Lower Estuary, but at a higher level of similarity. All animal assemblages consisted of the following sessile species: Obelia longissima (Pallas), Hiatella arctica (L.), Mytilus edulis L., Balanus balanoides (L.) and B. crenatus (Bruguière). These species formed over 95% of biomass of all sessile species. Differences between the various station assemblages were mainly due to changes in the relative abundance of these species. The geographical gradient of summer surface water temperature best explains the observed clusters. In the Lower Estuary, the spatio-temporal variations of physico-chemical factors and the surface circulation may influence the number of species and their abundance. The circulation systems of the Lower Estuary and near the Mingan Islands might account for the similarity between their assemblages. The same dominant species, Obelia longissima, characterizes the fauna of these two regions.     

Bois plio-pléistocènes du gisement de saropée plateau de khorat, est de la Thaïlande

Alluvial deposits from the Mue Nam Mum river at Saropée, Khorat Region, Thailand, yielded about 60 wood specimens, attributed to Araucarioxylon sp., Shoreoxylon thaïlandense n.sp., Careyoxylon pondicherriense Awasthi, Terminalioxylon coriaceum Prakash and Awasthi, Terminalioxylon burmense Mädel-Angeliewa and Müller-Stoll, Pahudioxylon sahnii Ghosh and Kazmi, Cynometroxylon schlagintweitii Müller-Stoll and Mädel, and Albizzinium eolebekkianum Prakash. This association, attributed to a Plio-Pleistocene age, evokes a mixed deciduous forest, probably not far from a river and ancient volcanoes. The presence of Araucariaceae in South-Eastern Asia at a relatively recent epoch is pointed out. A comparison with other fossil wood localities reveals close floristic resemblance with Burma, Western Bengal and Kachchh.

Résumé

Une nappe fluviatile de la rivière Mue Nam Mum, gisement de Saropée, région de Khorat, en Thaïlande, a livré une soixantaine de bois fossiles, déterminés comme: Araucarioxylon sp.,Shoreoxylon thaïlandense n.sp., Careyoxylon pondicherriense Awasthi, Terminalioxylon coriaceum Prakash et Awasthi, Terminalioxylon burmense Mädel-Angeliewa et Müller-Stoll, Pahudioxylon sahnii Ghosh et Kazmi, Cynometroxylon schlagintweitii Müller-Stoll et Mädel et Albizzinium eolebekkianum Prakash. Cette association, évoquant une forêt semi-dense, s'est vraisemblablement développée à proximité d'un cours d'eau et d'anciens volcans. Elle est attribuée au Pliocène ou au Quaternaire ancien. La question de la présence d'Araucariaceae dans le Sud-Est asiatique à une époque relativement récente est évoquée. Une comparaison avec d'autres gisements à bois fossiles révèle des ressemblances floristiques avec la Birmanie, le Bengale occidental et le Kachchh.