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1.
《Geobios》1986,19(5):549-571
The paleoflora described and pictured in this paper has been collected in two deposits of the area of Demnate: the OT6 bis drilling in the oriental Haouz and an exposure in the Rhojdamas (High-Atlas). Two completely different associations have been characterized: one hygrophilous and autochtonous of the «Stephanian type and the other mesoxerophilous and allochtonous (vegetation of the upland?) of the «Autunian type. In the OT6 bis drilling, the two floras alternate so that it is impossible to draw a precise boundary between the Stephanian and Autunian. In the Rhojdamas, only the Autunian flora has been identified. Such a combination of the two floras has similarly been recorded in several stephanian basins of the French Massif Central.  相似文献   

2.
《Geobios》1987,20(6):789-810
The micropaleontological and sedimentological analysis of the cuttings and core-samples extracted from a certain number of borings conducted seaside Casamance, western Casamance and eastern Casamance (fig. 1), enabled the researches to determine Casamance stratigraphy and paleoecology during the tertiary period. The microfauna gathered (foraminifera and ostracoda) makes it possible to characterize the biozones P1 to P15/P16 followed by the biozones N1/N2 to N14, bringing into evidence the existence of Paleogene and Neogene which are separated by a gap of changeable amplitude.The sedimentological study has revealed the presence of a certein number of landmarks and lithologic mineralogical sets which seem to be constant in the studied boring.  相似文献   

3.
Résumé Le tégument de Glossiphonia complanata comprend, outre les cellules épithéliales banales, de nombreux organes particuliers ou organes de Bayer, regroupés essentiellement sur la face dorsale de l'animal. Ils sont formés par une cellule apicale saillante enchassée dans une cellule musculaire en anneau.L'ensemble de ces formations est étudié du point de vue ultrastructural. Des cellules épithéliales partent des fibres nerveuses afférentes, sans doute vecteur des perceptions de stimuli mécaniques de pression au niveau du tégument; la réponse se faisant sans doute par la contraction de la cellule basale de chaque organe de Bayer, innervée par des fibres nerveuses efférentes, entrainant la saillie de la cellule apicale. Le hérissement de ces nombreuses papilles du tégument dorsal pourrait être un signal perçu par le partenaire sexuel, chez cette Hirudinée à fécondation hypodermique.
Ultrastructure of the integumentary epithelium of Glossiphonia complanata (L.) (hirudinea): Epithelial cells and sensory organs of bayer
Summary The integument of Glossiphonia complanata, built up by epithelial cells, contains numerous particular organs (Bayer organs), mainly on the dorsal side of the animal. They consist of a protuberant apical cell, which is surrounded by a ring-shaped muscle cell. All the integumentary formations are studied from an ultrastructural point of view. From the epithelial cells issue afferent nerve fibres, considered as vectors of the perception of mechanical stimuli of pressure at the level of the integument; the response no doubt operating by the contraction of the basal muscle cell of each Bayer organ, innervated by efferent nerve fibres, bringing forth the protrusion of the apical cell. The erection of these numerous papillae of the dorsal integument might be a signal perceived by the sexual partner, fecundation occurring in this group of leeches under the integument.
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4.
The development of phylogenetic methods since the beginning of the 1970s is analyzed through Armand de Ricqlès’ comment, in 1975, on the triumph of the spirit of geometry over the spirit of finesse. Cladistics was then compared to geometry (Hennig's congruence [i.e. congruent character-state trees]). However, the qualitative aspect of anatomy (spirit of finesse) warrants the quality of a taxon × character matrix so that minimal length trees were never devoid of finesse. Statistical approaches, especially maximum likelihood and Bayesian methods, with sophisticated mathematics (more rigorous geometry?), have reached a wide acceptance after years of debates hindered by polemics. The molecular trees based on these approaches are now dominating the phylogenetic literature, although these trees too include some ambiguity so that one can wonder: do evolutionary models belong to geometry or finesse?  相似文献   

5.
This paper deals with the aerophytic Cyanophyceae from New Caledonia sampled by Prof. Dr A. Guillaumin from Paris, Dr M.G. Baumann-Bodenheim from Zürich, Dr H. Hürlimann from Winterthur and Prof. Baas Becking from Noumea. A total of 124 samples were studied, most of them collected on soil, stones, rocks and barks. The characteristics of these samples are given. Among species, varieties and forms, a total of 85 taxa were recorded. Among them three are new for science, Gloeothece neocaledoniense nov. sp., Hydrocoryne neocaledonica nov. sp. and Scytonematopsis neocaledoniense nov. sp. One new combination is proposed, Petalonema involvens var. elongata (Bourr.) nov. comb.  相似文献   

6.
A model coupling a 2D transport equation and a simple model of the nitrogen cycling was developed for the Thau lagoon (France). The model took into account the wind forcing on the hydrodynamism, the effect of the temperature on the biological processes, the input of the watershed area, the light dependence of the pelagic primary production and the prédation of the phytoplankton by the cultivated filter feeders. The model ran under two steady-state situations of wind with constant temperature and light values corresponding to spring weather conditions. Simulations showed that the biological flows were very sensitive to the wind. The budget of the nitrogen flows were computed for the three areas devoted to the filter feeder cultivation and the results highlighted the impact of cultivated oysters as a source of nutrients and an important nitrogen flow through the predation of phytoplankton.  相似文献   

7.
Résumé Le microscope électronique à balayage montre l'existence d'un réseau complexe de microcrêtes à la surface de la vésicule vitelline et du sac péricardique de l'embryon de Poecilia reticulata. Cette étude permet également de préciser la localisation, l'aspect et la répartition des «cellules à chlorure» et de proposer un schéma tridimensionel de l'organisation infrastructurale de la paroi de la vésicule vitelline. Un choc osmotique détermine rapidement un mouvement d'étalement des cellules épithéliales sur la surface apicale libre des «cellules à chlorure». La signification de ces résultats est discutée en rapport avec le problème de l'osmorégulation embryonnaire chez les Poissons, en particulier chez les Cyprinodontes vivipares de la famille des Poeciliidae.
Ultrastructure of the yolk sac and pericardial sac surface in the embryo of the teleost Poecilia reticulata
Summary A complex network of microridges is revealed by scanning electron microscopical examination of the yolk sac and embryonic pericardial sac surface of Poecilia reticulata. This study also specifies the localization, aspect and distribution of the chloride cells. A tridimensional diagram of the ultrastructural organization of the yolk sac wall is suggested. Osmotic stress quickly induces an overlapping of adjacent epithelial cells on the free apical surface of the chloride cells. These findings are discussed in relation to the problem of embryonic osmoregulation in fishes and especially in viviparous Poeciliids.
Nous exprimons notre gratitude à Mme Neumann, Directeur du Laboratoire de Micropaléontologie de l'Université Paris VI, qui nous a permis d'utiliser le microscope électronique à balayage qui a servi à cette étude. Nos remerciements s'adressent aussi à Melle Aubry et à M. Saussé pour leur concours technique. — Les observations en microscopie électronique en transmission ont été effectuées au Laboratoire de Microscopie électronique appliquée à la Biologie du C.N.R.S.  相似文献   

8.
Annick Isaia 《Planta》1971,96(2):175-182
Summary The activities of (±)-abscisic acid and a number of compounds derived from p-coumaric acid and coumarin and their interaction with gibberellic acid in the control of the elongation of the first wheat leaf are examined. (±)-Abscisic acid strongly inhibits leaf growth in the presence as well as in the absence of gibberellic acid, but the inhibition is greater in the presence of gibberellic acid (3 g/l already have an observable effect). Among other compounds, only ferulic acid and coumarin significantly reduce leaf elongation, and they are effective only at high concentrations (1.44 · 10-4 M/l).  相似文献   

9.
The archaeological units of the Baume-Vallée rock shelter (Haute-Loire) in the South-East of the Massif Central, excavated by A. Laborde (from 1966 to 1973) then by J.-P. Raynal (from 1974 to 1996), have yielded abundant lithic assemblages attributed to the late Middle Paleolithic, characterized by a remarkable diversity of the raw materials used. The lithic industry of the upper units had previously been described as belonging to the Charentian facies lato sensu, then was attributed to the Ferrassie-type Mousterian. The technology and the techno-economic revision of its upper assemblage bring new information on the flaking mechanisms and the steps of the chaînes opératoires. These data tend to include this assemblage in the Levallois techno-complexes with scrappers often observed in late Middle Paleolithic of southeastern France.  相似文献   

10.
Resume Les expériences ont porté sur des lapins repartis en deux groupes parallèles — un groupe étant traité avec des aéroions négatifs en concentrations moderées (n = 10 – 40.000; n+ = 1.000) et l'autre sans aéroionothérapie (témoins). Par rapport aux animaux témoins (pas exposés aux aéroions),on a enregistré,sous l'influence de l'aéroionothérapie, que: (1)il y a une tendence de normalisation de la motilité spontanée, deprimée par une alimentation contenant un excès de cholestérol(0,3 g/kg/jour); (2) la lipémie et la cholestérolémie sont restées à un niveau plus bas chez les animaux alimentés au cholestérol; (3) la lipémie et la cholestérolémie, de même que l'iode thyroïdien, sont restées aux valeurs voisines de celles normales,chez les animaux nourris avec un excès (20 mg/kg/jour), de substances antithyroïdiennes naturelles (provenant du chou).
Groups of rabbits were exposed to negative air ions of moderate concentrations (n = 10 – 40,000; n+ = 1,000) while others served as controls. (1) When rabbits were fed a cholesterol-rich diet (0.3 g/kg/day)causing reduction of motility in the control animals, their motility was normalized under air ion treatment. (2) The blood cholesterol and lipid levels of rabbits on a cholesterol-rich diet were lower with air ion treatment than in controls.(3) When rabbits were fed a diet with thyroid blocking agents from cabbage the blood cholesterol and lipid levels and the thyroid iodine content remained unchanged with air ion treatment.

Zusammenfassung Gruppen Kaninchen wurden mit negativen Luftionen in mässigen Konzentrationen (n = 100 000 – 40 000; n+ = 1 000) behandelt, während andere als Kontrollen dienten. (1) Die durch Fütterung von cholesterinreicher Diät (0,3 g/kg/Tag) verminderte Motilität der Tiere wurde unter der Luftionenbehandlung normalisiert. (2) Der durch Fütterung von cholesterinreicher Diät erhöhte Blutcholesterin- und-fettspiegel fiel durch Luftionenbehandlung ab. (3) Der durch Fütterung von strumipriven Substanzen aus Kohl erhöhte Cholesterin- und Fettspiegel im Blut und verminderte Jodgehalt der Schilddrüse wurde durch Luftionenbehandlung nicht beeinflusst.
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11.
Hypenia violacea (Lamiaceae), a new species from Guerrero, Mexico, is described and illustrated. This species is characterized by glabrescent, coriaceous leaves, lax thyrsoid inflorescences with pedunculate and umbelliform cymules that have 3–6 violet flowers with corollas 0.8–1.6 cm long. The species is referred to the Southern American genus Hypenia.
Resumen  Se describe e ilustra Hypenia violacea (Lamiaceae), una especie nueva de Guerrero, México. Presenta hojas coriáceas, glabrescentes, inflorescencia tirsoide, laxa, con címulas umbeliformes, pedunculadas, con 3–6 flores por címula, flores de color violeta, de 0.8–1.6 cm largo. Las características observadas corresponden, en su mayoría, a Hypenia, un género de distribución sudamericana, por lo que se incluye en el mismo.
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12.
《Geobios》1987,20(1):123-127
The teleost fish Brychaetus and a dyrosaurid crocodilewere recognized among the aquatic vertebrates recently discovered in the northern area of the Titicaca lake (Bolivia). These fossils allow the presumption of a Paleocene age for the vertebrate bearing formation. The structural interpretation of this chronological data is discussed.  相似文献   

13.
Résumé Les auteurs ont isolé plus de 700 souches de bactéries lactiques à partir de raisins, de moûts, de vins de diverses origines et à différents stades de conservation. Ils étudient ici 253 souches de bacilles hétérofermentaires, dans le but d'établir une classification simple et un catalogue permettant un repérage facile des souches.Il est commode de classer les souches d'après la fermentation des pentoses, en raison de la netteté de ces tests, alors que parfois ceux appliqués à d'autres sucres ont des caractères moins tranchés. On retrouve alors la classification qui avait été déjà donnée par Vaughn, Douglas et Fornachon en 1949.Les bacilles pentoses négatifs (26 souches) forment l'espèce Lactobacillus fructivorans. Ceux qui font fermenter seulement l'arabinose (4 souches) ou seulement le xylose (155 souches) correspondent respectivement à Lactobacillus desidiosus et à Lactobacillus hilgardii. L'espèce Lactobacillus brevis comprend les bacilles pentoses positifs (68 souches).
A study of two hundred and fifty strains of lactic acid bacteria
Summary The authors have isolated more than 700 strains of lactic acid bacteria found in grapes, musts and wines of various origins and at different states of conservation. They study in this work 253 strains of heterofermentative bacilli in order to work out a classification and a catalogue allowing easy identification of the strains.It is convenient to classify the strains from the fermentation of pentoses, on account of the accuracy of these tests, tests on other sugars having sometimes less specific characters. The results are consistant with the classification already established by Vaughn, Douglas and Fornachon in 1949.Pentose negative bacilli (26 strains) constitute the species Lactobacillus fructivorans. The ones which ferment only arabinose (4 strains) or only xylose (155 strains) correspond to Lactobacillus desidiosus and Lactobacillus hilgardii. The pentose positive strains (68) belong to the species Lactobacillus brevis.
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14.
《Geobios》1988,21(3):269-305
The present statistical study of two Bajocian populationsof Isastrea from eastern France uses different methods of measurement taking into account the colonial character. The results of the univariate and the multivariate analyses together with direct observation of qualitative characters show that only two species are present in the samples: Isastrea bernardiana and I.tenuistriata. A new synonymy is suggested for the Bajocian species. Genera such as Andemantastraea All. and Parisastraea All. correspond to the common variation of Isastrea. The taxonomic position of other Jurassic Isastrea is examined. It is probably possible to use extreme morphotypes as stratigraphic markers owing to an eventual anagenesis.A comparison between the two samples denotes that the variation range or the mean value of some quantitative characters (number, thickness of septa, dimension of corallites, trabecular density) contributes to the paleoecological interpretation.The present paper emphasizes the necessity ofwell-defined species based preferably on population study, for a reliable generic definition.  相似文献   

15.
16.
Radiopharmacists of the Nuclear Medicine department of hospital Tenon have prepared and controlled the 68Ga-labeled DOTATOC, for 4 years, as part of a clinical research study. The aim of this article is to share our experience, since this activity is not yet developed in France. Radiolabelling of DOTATOC (68Ga) requires the settling of a 68Ge/68Ga generator, which is connected to an automated PC-controlled radiopharmaceutical labelling device (Elusynth 68Ga, Iason) and comprises several steps. Performed quality controls (QC) are those commonly used for radiopharmaceuticals including: appearance, pH, radiochemical purity (RCP), radionuclide purity (PRN) and determination of the physical half-life. Bacterial endotoxins and sterility tests are systematically done. We obtained a mean value of radiolabelling yield around 45%. The results of QC are always in accordance with the specifications. The preparation failed in 7% of the 195 DOTATOC (68Ga), over the last 4 years. It is important to note that the preparation of DOTATOC (68Ga) monopolizes the radiopharmacist during 3 hours. This radiolabelling technique can be easily applied to other peptides, in order to develop other 68Ga-labelled PET tracers.  相似文献   

17.
Four aromatic bromo compounds have been isolated from the ethanolic extract of Rytiphlea tinctoria after treatment with diazomethane: 2,4-dibromo-1,3,5-trimethoxy-benzene,5,6,3′,5′-tetrabromo-3,4,2′,4′,6′-pentamethoxydiphenylmethane, 5,6-dibromo-3,4-dimethoxy-benzyl alcohol and its ethyl ether. In addition to sterols, amino acids, this extract also contains quinonoid bromo-pigments which could play a rôle in photosensitisation of chlorophylls, a rôle normally taken by the phycobilins, in other Rhodophyceae.  相似文献   

18.
Absence of the vas deferens is a rare cause of male infertility, associated with mutations in the cystic fibrosis transmembrane regulator (CFTR) gene in about 80% of cases. Only limited published data are available concerning the correlation between genotype and reproductive tract abnormalities observed in this disease: presence or absence of seminal vesicles and parts of the epididymis, symmetrical or asymmetrical lesions, testicular volumes. We screened 47 patients for the 13 most common CFTR mutations on the cystic fibrosis gene and for the 5-thymidine variant of the polythymidine tract of intron 8. Renal, scrotal and transrectal ultrasonography was performed in each patient to explore the testes and reproductive tract. All patients presented absence of the ampullae of the vas deferens. Forty patients presented bilateral absence of the vas deferens and 7 presented unilateral absence of the vas deferens. At least one mutation of the cystic fibrosis gene was present in 64% of cases: 47% had the ΔF 508 mutation and 63% had the 5T allele. No mutation was detected in seventeen patients, including 3 patients with unilateral renal agenesis and 3 patients with unilateral absence of the vas deferens. No differences were observed for seminal vesicles and symmetry of vesicular and epididymal abnormalities between patients with or without CFTR gene mutations, but epididymal abnormalities were significantly more frequent in the group without mutation (p=0.01). Testicular volumes were significantly lower in the patients without mutation or with the 5T allele only, than in the patients with at least one CFTR gene mutation: 10.7±4.1 ml versus 15.1±4.5 ml, respectively (p<0.001). In conclusion, in cases of isolated absence of the vas deferens, there is no difference in sperm duct abnormalities between patients with or without CFTR gene mutation. These results suggest that other genetic or environmental determinants are required to explain a common pathogenesis for these malformations. The decreased testicular volume of patients without CFTR gene mutation or with the 5T allele only suggests the existence of an unidentified secretory or mixed factor involved in these forms of absence of the vas deferens.  相似文献   

19.
20.
Résumé Au cours de l'épitoquie des Nereidiens, les fibres musculaires longitudinales ne sont pas forméesde novo, à partir de cellules indifferenciées ou myoblastes, mais proviennent des fibres anciennes atoques. Celles-ci subissent une véritable dédifférenciation plus ou moins synchrone d'une redifférenciation. Les deux processus ne sont pas successifs mais simultanés, et une dédifférenciation complète est absente.Les premières cellules en évolution appartiennent à la couche musculaire externe; ensuite, les fibres des assises plus profondes se transforment à leur tour.Les transformations consistent en: 1) La dédifférenciation du bord interne ou coelomique de la fibre. Les structures contractiles disparaissent dans cette zone et de nombreuses particules de glycogène se différencient sans relation avec le reticulum endoplasmique ou les ribosomes. Aucun lysosome ou signe précurseur ne peuvent être observés avant la disparition des filaments contractiles et des éléments Z. 2) Le bord coelomique s'hypertrophie. Dans la région axiale de la fibre, de nombreuses mitochondries et particules et de glycogène remplacent le matériel contractile. Corrélativement, l'épaisseur des bandes A et I diminue. 3) La fibre hétéronéreidienne ou épitoque est constituée et présente deux parties: un cortex myoplasmique et une médulla sarcoplasmique, remplie de mitochondries et de glycogène. Le noyau renfermant un nucléole volumineux est situé dans une hernie sarcoplasmique latérale.
Evolution of muscles inNereidae (Annelida polychaeta) during Epitoky. III. Dedifferentiation of the longitudinal fibres
Summary During epitoky inNereidae, the longitudinal muscle fibres are not formedde novo from undifferentiated cells or myoblasts, but arise from the old atokous fibres. These undergo a true dedifferentiation more or less synchronously with a redifferentiation. The two processes are not successive but simultaneous and there is no complete dedifferentiation.The first cells that develop are in the outside muscle layer; then the fibres of the inside layers are transformed in their turn.The transformations consist of: 1) Dedifferentiation of the edge of the inner or coelomic fibre. The contractile structures disappear in this part and numerous glycogen particles differentiate, unrelated to endoplasmic reticulum or ribosomes. No lysosomes or precursory markings are observed before the disappearance of contractile filaments and Z rods. 2) The coelomic edge becomes enlarged. In the axial region of the fibre, numerous mitochondria and and glycogen particles take the place of the contractile material. Consequently, the thickness of A and I bands decreases. 3) The heteronereid or epitokous fibre is formed and shows two parts: a myoplasmic cortex and a sarcoplasmic medulla, filled with mitochondria and glycogen. The nucleus with a voluminous nucleolus settles inside a lateral sarcoplasmic swelling.
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