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1.
Dirk Nolf 《Geobios》1978,11(4):517-559
The study of approximately twenty three thousand otoliths from Plio-Pleistocene sites in the harbour region of Antwerp, as well as a critical revision of already published material allowed us to identify a teleostean fauna with fourty seven species (including two subspecies and seven species in open nomenclature). Two of these, Ophidion springeri and Uranoscopus septentrionalis are new to science. The fauna is typical for coastal waters slightly warmer than those of the actual North Sea and caracterized by the predominance of Gadidae. Biostratigraphically this fauna is well individualized with respect to preceeding ones (only seven species in common with the Miocene fauna) and those following twenty-three species in common with the extant fauna). The following biostratigraphical subdivision has been recognized in the Upper Miocene and the Plio-Pleistocene of the Antwerp region: (1) an association with «genus? Macrouridarum labiatus, Trisopterus sculptus, Gadiculus benedeni and Trisopterus luscus spectabilis, in the Sands of Deurne (Upper Miocene); (2) an association with Gadiculus benedeni and Merlangius pseudaeglephinus, in the Formation of Kattendijk (Pliocene); (3) an association with Gadiculus verticalis and Merlangius pseudaeglefinus in the Formation of Lillo (Plio-Pleistocene); (4) an association with Gadus morhua and Merlangius pseudaeglefinus in the so called «Icenian deposits not present in Belgium but found in the Netherlands.  相似文献   

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《L' Année biologique》1999,38(2):107-122
Calcified structures such as otoliths have been used successfully for estimating the age of teleost fishes for many years. Otoliths record age as well as annual and/or seasonal events in the lives of fish and they are an important source of life history information. Otoliths have been found to contain characteristics that are stock specific. Elemental composition might be useful for identifying non-mixing groups of fish that may be regarded as separate stocks for fisheries management. Examination of otolith microstructure has been used to study early life history. Papers describe the use of otolith microstructure combined with chemical analysis to assess the relative significance of environmental variables: feeding frequency, photoperiod and temperature, migration from freshwater to marine water, pollution, etc. Otoliths are the first calcified structures that appear during the early development of fish and they provide a more adequate record of the growth history than scales. Otoliths represent the black box of teleost fish.  相似文献   

5.
Conclusion L'hypothèse que nous venons d'esquisser n'est certainement pas une généralisation définitive et elle devra subir de nombreuses retouches avant de pouvoir englober tous les faits connus, mais n'est ce pas là le propre de toutes les généralisations à leur début?Actuellement la théorie du potentiel-force d'attraction et de l'adsorption orientée a le gros avantage d'expliquer la plus grande partie des faits bien établis, ce qui constitue un progrès incontestable et très précieux.  相似文献   

6.
《L'Anthropologie》2022,126(2):103020
North Africa, and in particular the Maghreb, is a key region for African prehistory in that it contains sites whose chronology covers the entire Pleistocene period from 2.5 Ma to the Holocene. In terms of culture, it fits into the general pattern of the Stone Age, but it has particularities that make it a region apart with its own cultures. Due to its climate and geographical position, between the desert regions of the south and the Mediterranean Sea to the north, it has offered mankind a diversity of landscapes and environments that are quite unique and favorable to the development of human evolution. Finally, this region gives access to Europe through several maritime passages (Gibraltar, Sicily), which were probably used during the Pleistocene, thus reinforcing the interest in studying this northern part of Africa. The recent development of numerous dating methods has made it possible to reinforce and consolidate the chronostratigraphic framework, which for many years had been based solely on radiocarbon dating. These methods have sometimes even contributed to the confirmation of ‘new’ ideas that have dusted off the existing framework of prehistory. This article presents a chronology of the main ancient sites of the Maghreb dated by different methods whose ages compared to the results obtained by other disciplines participate and contribute to a better understanding of the environmental and cultural framework of prehistoric Man.  相似文献   

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Résumé Les recherches histochimiques sur l'ATPase-Na+-K+ en microscopie optique ont permis de mettre en évidence une forte activité au niveau de l'épithélium pseudobranchial des Téléostéens.Cette activité est localisée sur la membrane interne des cellules pseudobranchiales, qui fait face aux larges espaces extracellulaires de la région interlamellaire. Cette région interlamellaire contient de nombreuses terminaisons nerveuses afférentes. La spécificité de ces localisations est discutée.
Attempt at histochemical localization of the Na+-K+ activated ATPase of teleostean pseudobranchia epithelial cells
Summary The histochemical studies of the ATPase-Na+-K+, at light microscopic level, showed a strong activity in the pseudobranchial epithelium of a teleost fish. This activity is located on the inward membrane of the pseudobranchial cells facing the large extracellular spaces of the intralamellar areas. These intralamellar areas contain numerous afferent nerve endings. The reality of these localizations is discussed.
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Conclusion La technique à l'hématoxyline au plomb de Mac Conaill permet l'identification d'un type cellulaire situé dans la pars distalis rostrale, en bordure des ramifications de la neurohypophyse dans l'hypophyse de plusieurs Poissons Téléostéens; il est également colorable par le bleu d'alizarine d'Herlant; toutefois, l'intensité de ces deux réactions tinctoriales est très variable selon les espèces. Chez l'Anguille, les Salmonidés et le Cyprin, la nature corticotrope de ces cellules est établie expérimentalement. La colorabilité par l'hématoxyline d'une autre catégorie cellulaire dans la pars intermedia laisse supposer l'existence de constituants communs aux deux types cellulaires, et peut-être même à leurs produits d'élaboration. Cette communauté de certains aminoacides entre l'ACTH et l'intermédine a déjà été démontrée chez divers Mammifères.  相似文献   

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A survey of the nitrophilous fringe communities of the region Marche (Central Italy) allows the individualization of five associations well characterized floristically and ecologically. These are:Urtico-Aegopodietum, Anthriscetum sylvestris, Chaerophylletum aurei, Alliario-Chaerophylletum temuli, andAnthriscetum nemorosae. The first three associations are ranged, from the phytosociological point of view, in the allianceAegopodion podagrariae, while the last two belong to the allianceGalio-Alliarion.  相似文献   

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《Comptes Rendus Palevol》2002,1(4):227-234
Two viperid snakes, Vipera natiensis sp. n. (belonging to the Vipera aspis group) and Vipera sp., have been found in the Pliocene of Minorca. On the other hand, an indeterminate viperid extends back the fossil record of the family in the Balearic Islands, to the Middle Miocene. These fossils represent the first report of viperids from the Balearic Islands. Vertebra of Vipera natiensis sp. n. are characterised by a concave anterior border of zygosphene, dorsoventrally flattened, short (as wide as long) and blunt prezygapophyseal processes. Centrum convex in transverse section, subcentral margins poorly marked and presence of two well defined subcotylar tubercles. Hypapophysis located posteriorly on the centrum and not prolonged anteriorly, or only slightly prolonged as a keel. The dorsal border of the neural spine is slightly thickened; the posterior border of the neural spine is markedly inclined posteriorly; as a result, the spine forms a posterior point, which is more or less developed, depending on the position of the vertebra along the vertebral column. The presence of Viperidae in the Neogene of the Balearic Islands involves the existence of a terrestrial connection between this archipelago and the continent during the Early Miocene and/or Middle Miocene and perhaps the presence of a later connection during the Late Miocene.  相似文献   

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Résumé  Parmi les nombreux squaliformes récoltés dans le Lutétien des Landes (SO de la France), deux genres et espèces nouveaux ont été reconnus:Squaliodalatias weltoni n. gen. n. sp. etAngoumeius paradoxus n. gen. n. sp. La morphologie dentaire du premier permet de le rapprocher des Dalatiidae. Les relations phylétiques du second taxon sont pour 1’instant moins claires, en raison de sa denture supérieure inhabituelle pour un Dalatiiforme aussi évolué au niveau de la denture inférieure. Ces taxa nouveaux viennent enrichir nos connaissances sur un groupe encore mal connu à l’état fossile en raison de son habitat bathyal ainsi que sur la mise en place et la radiation, encore trop peu documentée, des faunes profondes.   相似文献   

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《Annales de Paléontologie》2017,103(4):283-292
Thirteen species of macroinvertabrates have been identified for the first time from the Turonian deposits of the Libreville region. Seven ones correspond to bivalves: Lima (Plagiostoma) subsimplex Thomas and Péron, 1890, ?Osteomya sp., Plicatula ferryi Coquand, 1862, Pfourneli Coquand, 1862, Pventilabrum var. suffetulensis Pervinquière, 1912, Plicatula sp., Pleuromya sp.; three other ones are echinoid species: Mecaster batnensis (Coquand, 1862), Mecaster nicaisei (Coquand, 1862), Mecaster sp.; and the last three are gastropods: Cylichna sp. ? Pterocerella poinsettiformis Stephenson, 1941, Columbellina sp. Excepted Plicatula ferryi Coquand and Pventilabrum var. suffetulensis Pervinquière which are identified in the Senonian of Gabon, all species are found for the first time in Gabonese coastal basin. Their paleobiogeographic distribution is extended to Gabon. In Gabonese coastal basin, the stratigraphic and geographic ranges of the Plicatula genus are extended in Turonian and Libreville region respectively. The macrofaunal assemblage found in the Libreville region is cosmopolitan. Its shows paleogeographical affinities with Tethys and south of South Atlantic.  相似文献   

15.
The osteoid osteoma is a small benign, painful, bony tumour in which the treatment consists of a complete surgical ablation. The cases of recurrence often correspond to an incomplete surgical ablation. We report, in this work, the advantage of isotopic intraoperative marking for an accurate and complete excision of the pathological lesion in a young patient, during his surgical resumption after the short-term failure of the first intervention, which was accomplished without intraoperative location, and completed with a literature review.  相似文献   

16.
Paul Sentein 《Chromosoma》1966,19(4):357-398
The eggs of some Amphibian species (Triturus helveticus Raz., Triturus alpestris Laur., Xenopus laevis Daud.) are more resistant to selenium dioxyde M/100 than eggs of Pleurodeles waltlii Michah. Minimal mitotic abnormalities are observed: 1. “empty” poles, 2. cupular poles, 3. escape of centrosphere, which separates from the spindle, and sometimes torsion of polar regions of the achromatic figure. Cytasters and newly formed spindles are also observed in the diastematic clear zone, which is dissociated and inefficient. These abnormalities are believed to be consequences of the progressive diminution of a dominant factor associated with the centriole. When dominance is weakened, secondary poles appear with or without relation to the spindle. The balance between fibrillogenesis and reproduction of centrioles is newly demonstrated. These mechanisms are compared with phenomena occuring during fertilization and parthenogenesis  相似文献   

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《L'Anthropologie》2021,125(3):102905
New surveys were undertaken in Abbeville in 2016 and 2017 on the site of the Moulin Quignon discovered before 1850 by Boucher de Perthes, relocated thanks to the archival work carried out by MNHN researchers. This research led 150 years later to the rediscovery of this emblematic Paleolithic site. Test pits and extensive excavation have led to the discovery of alluvial levels in situ and a lithic series composed of 254 fragments, 15 cores and 5 bifaces. The cores and flakes attest to in situ debitage on flint nodules according mainly to unipolar and centripetal unifacial technology, except for one core, which indicates a management on several debitage surfaces. The bifaces are diversified morphologically and technically (shaping modes). They attest to a general management of the bifacial volume and geometry of the tool, to the care taken at the tip of the tool and to the regularisation of the often peripheral edges. They resemble those discovered by Boucher de Perthes in 1837–1868 and described in the past as “Abbevillian”. Stratigraphic and ESR age studies on quartz date human occupation between 670 and 650 ka. These artifacts belong to the earliest Acheulean occupation ever dated in the Somme basin and more generally north of the 50th parallel north. The lithic series discovered at Moulin Quignon is indisputable proof of the presence of human occupations dated at more than 650 ka in the Somme valley, a natural pathway to northern sectors, present-day Great Britain. This discovery thus ages (1) the age of the oldest occupation in the North of France (previously 550 ka) and (2) the age of the oldest bifaces for Northwest Europe (100 ka older than the bifaces in Great Britain).  相似文献   

19.
《IRBM》2008,29(5):302-309
PurposeThe aim of our study is to provide an update on the basic concepts and methodologies implemented in the healthcare information systems to identify the patient.MethodThe method used is an analysis of the existing intrinsic and extrinsic systems linked respectively to their objectives and ethical requirements, and an open methodological and scalable study based on finding a unique and universal identifier.ResultDespite many constraints our analysis of various tasks shows that some solutions are attainable. They are focused on a simple identification model responding to the different concepts developed and setting up systems for efficient and reliable networking. The model proposed here is based on the criteria shared by all. It portrays the main elements sought by the users of the healthcare information systems. However, its implementation requires a well-defined organization that allows a coherent and permanent usage over the time namely: a precise definition of features and the hash modalities, the processing of this information, the networking procedures… and so on. This proposal takes into account the existence of different information systems and subsystems. The consistency between these different systems must go with a good interoperability and above all a flawless identification of the data related to the patient.ConclusionThe solutions allow a reliable and versatile patient identification system consistent with the principles of privacy standards.  相似文献   

20.
《Comptes Rendus Palevol》2002,1(7):587-598
One of the major contributions of Alcide d’Orbigny to palaeontology is his work on the Danian of the Paris Basin. The Danian material includes well-preserved external imprints of Invertebrates. By making casting of these imprints, Alcide d’Orbigny inaugurated an original technique, which enabled him to describe more than 40 species. The question of the age of the Danian localities has long been debated since that time. It was settled once and for all in the seventies by micropalaeontologists.  相似文献   

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