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1.
J. Rey  M. Bilotte  B. Peybernes 《Geobios》1977,10(3):369-393
The marine Albain from Estremadura is splited up into four Orbitolinidae zones, adjusted to biostratigraphic scales from mesogean province: zone with Orbitolina (Mesorbitolina) minuta (lower to middle Albian); zone with Neorbitolinopsis conulus (base of upper Albian); zone with Orbitolina (Orbitolina) concava (top of upper Albian) and zone with Orbitolina (Orbitolina) duranddelgai (Vraconian). The vertical extension of the main fossils is replaced in the framework of these zones. The most interesting species for biostratigraphy, paleoecology or taxinomy are summarily described.  相似文献   

2.
From the Aptian scolecodonts inventory of the Agadir area one jaw apparatus and one joining of polychetes are reconstructed. One is the elementary species Schistomeringos expectatusSzaniawski & Gazdzicki, 1978, the oldest representative of the multielementary family Dorvilleidae Chamberlin 1919. The other is a representative of either the multielementary families Atraktoprionidae Kielan Jaworowska 1966 emend. Kozur, 1970 or Arabellidae Hartman 1944. This joining is considered as an hypothesis since all the necessary criteria, defined by H. Szaniawski & A. Gazdzicki 1978, are not all present.  相似文献   

3.
Philippe Duringer 《Geobios》1982,15(2):125-145
Experiments have been carried out in laboratory onplastic cephalopod models in order to study most aspects of sedimentary shell filling of Ceratites and Nautilus from the German Upper Muschelkalk. In most cases the shells had a horizontal position when being filled by the sediment. The exception of filling in upright position has been observed mainly for Ceratites nodosus nodosus (Bruguière, 1792), Acanthoceratites spinosus (Philippi, 1901) except the species A. spinosus penndorfi (Rothe, 1955), Acanthoceratites evolutus (Philippi, 1901) and the nautilus Germanonautilus bidorsatus (Schlotheim, 1804); it is due to the width of their shells. In no case the sediment filling of cephalopod shells gives information about the depth of the depositional environment. On the other hand it is a good indicator of the waving occurring on the sea floor and the reworking of the sediment.  相似文献   

4.
The question of the age of «Hauts de Meuse coral rag is studied again using new faunas of brachiopods and ammonites collected above, below and inside the coral rag. Ammonites fauna of the well known «Calcaires de Creuë is revised. Results obtained agree closely.The «Hauts de Meuse coral rag grew up during Middle Oxfordian time; and extend part of the Plicatilis zone (Antecedens Subzone) and the whole Transversarium Zone up to the basis of the Bifurcatus Zone, for the first time identified in Lorraine. So it span a short depositional time, about 1 MY, with a high deposition rate, the thickness of the coral rag being more than 100 meters, reaching 150 meters in Saint-Mihiel area. Towards SE, on the other side of the Marne Gap, the sudden change into basinal facies go with a reducing of thickness and deposition rate.Upper Oxfordian deposits show a relative uniformity of facies and thickness. At the top of Middle Oxfordian limestones, the age of the discontinuity and the Sequanian renewal of deposition is basal Bifurcatus Zone. Erosional renewal and terrigeneous deposits are a wide spread event by the beginning of Upper Oxfordian.In the paleontological part, species upon which are based new ages and interpretations are only figured, except the species new or with new paleontological data, which are described. Type specimen of Perisphinctes mosensisBayle, from the «Calcaires de Creuë, is described and photographically figured for the first time.  相似文献   

5.
Since the first publication on the detection of sperm-agglutinating antibodies in infertile men, multiple assays have been described. The most useful tests are able to detect antibodies bound to the sperm membrane of motile spermatozoa. The immunobeads test (IBT) is considered to be the most advantageous in terms of its sensitivity, the low incidence of false-positive results, and its ability to localize antibodies of different immunoglobulin classes on the sperm surface. The IBT assay can be used in parallel with the mixed antiglobulin reaction (MAR), to detect sperm-associated antibodies in the ejaculates of infertile men, the most rational way to test for antisperm antibodies (ASA) in males. In view of the high level of agreement between the two assays, MAR, the easier of the two, may be used as a first step in the detection of these antibodies. A positive MAR must be confirmed by IBT, as this assay is more specific for the detection of IgA antibodies. The clinical significance of sperm-associated antibodies is usually established according to the proportion of motile spermatozoa coated with immunobeads, its class and its localization on the sperm surface. However, binding of immunobeads does not provide any information about the antigens against which the antibodies are directed. As the functional effects of sperm-associated antibodies may vary as a function of their antigenic specificities, other assays, using purified fertilization related antigens, are necessary to establish, for each individual, the specific impact of the antibodies on the fertilization process. The indirect IBT assay has recently become the most widely used test to detect the various classes of ASA in serum and cervical mucus of infertile women and in the serum and seminal fluid of infertile men, in combination with the direct assay described above. However, in most laboratories, it is performed with only one dilution of the biological fluid tested, usually a low dilution, so that antibody levels of no significance for fertility could be detected. This may explain a recente debate (Human Reprod, 1999) on the significance of ASA as a cause of infertility. At present, and in the absence of standardized assays able to identify the antigens involved in each individual immune reaction, antibody assays, as detected by the IBT assay, in the serum and/or genital secretions of infertile subjects might provide useful clinical guidance.  相似文献   

6.
The white limestone represents a thick facies in the callovian stage of the threshold of Poitou. It makes the object of a detailed stratigraphical study which leads to its fauna and flora in the principal fossiliferous localities. The vertical range of Ammonites, layer by layer, leads to a chronostratigraphical subdivision in zones, subzones and shows up an important sedimentation break in the Upper Callovian in the axial region of the threshold of Poitou. Besides, a systematic study of plant remains gives original elements on the callovian flora in the West of France. These observations are completed by considerations of tectonic, sedimentary, paleographic and ecologic orders.  相似文献   

7.
13C NMR spectra of some tertiary and quaternary indole alkaloids are recorded and the signals assigned. Graphic interpretation of off-resonance spectra and substituent shielding effects together with the effect of Nb-methylation are utilized in the spectral interpretation.  相似文献   

8.
《L'Anthropologie》2016,120(5):588-609
The study of graphic convergences and divergences in Palaeolithic art is used to understand the culture, territories and interaction systems of human groups. La Covaciella cave has fifteen animal representations and other linear, dots and geometric motifs. The bison stands out; some were executed with complex technical procedures. Two of them were dated by C14 AMS, obtaining a result of 14,260 ± 130 BP (17,733–16,973 cal BP) and 14,060 ± 140 BP (17,503–16,260 cal BP). These correspond chronologically with the beginning of the middle Magdalenian or the very end of the lower Magdalenian. Similar depictions to the bison at La Covaciella are located in other areas of Western Europe. The repertoire of parietal bison displaying graphic similarities with those at La Covaciella is very large; both of the Pyrenean model (Niaux morphotype) and of the Perigordian model (Font-de-Gaume morphotype). A first consideration derived from the search for comparisons involves a new interpretation of the territorial value implied by the term Pyrenean style (Asturias, Cantabria, Basque Country, Navarre, Pyrénées-Atlantiques, Hautes-Pyrénées, Haute-Garonne, Ariège, Dordogne, Lot, Ardèche and Vienne). The Font-de-Gaume parietal morphotype is most common in Dordogne. In addition, in some cases, spatial complementariness has been found, with both graphic morphotypes. This article proposes different chronological and anthropological hypothesis to explain the distribution and coexistence of the two graphic models.  相似文献   

9.
Ecdysterone acts differently according to the period of the moulting cycle when it is applied. In period C it induces apolysis, while at the beginning of apolysis it delays ecdysis. Experiments show that the exoskeleton cannot be rejected in the presence of ecdysterone. The possibility of stopping exuviation or ecdysis with ecdysterone seems to prove that this phenomenon is controlled by a particular factor called the factor of exuviation or the ecdysis factor. Ecdysterone would control only the release of this specific factor but would not prevent its action.  相似文献   

10.
Bones have been collected from different geological sites, the sediment and the age of which being different. Comparizon between the mineral and organic phases shows the very fast alteration of the organic matrix in recent bones. Fossil bones show a loss in the organic matrices. Moreover, insoluble and soluble organic matrix alterations differ in a single bone. Implications of the diagenesis in palaeoenvironmental reconstruction and phylogeny are evoked.  相似文献   

11.
The ostracod fauna collected from the Cherahil formation that crops out at the Jebel Serj section (central Tunisia) contains 24 species belonging to 12 genera. These ostracods are associated with 9 genera of benthic Foraminifera (including 4 Nummulites species) and 7 genera of planktonic Foraminifera. The biostratigraphic study of ostracod assemblages results to the recognition of 6 biozones which are correlated with Lutetian-Priabonian. The Shannon Weaver, Margalef and equitability indices point to internal platform netritic conditions, with minor fluctuations in depth and oxygenation. The palaeobiogeographic distribution of ostracod species found in the study area of Central of Tunisia establishes a good connexion with the basins developed in Northern Africa (Tunisia, Algeria, Libya and Mauritania) and the Middle East (Egypt and Jordan).  相似文献   

12.
This work describes new species of ostracodes collected in the Middle and Upper Bathonian outcrops of the Grands-Causses, Southern France: Kirtonella vignesensis n. sp., Marslatourella bathonica n. sp., Micropneumatocythere montmejeaneansis n. sp., Praeschuleridea alzonensis n. sp., and illustrates the predominating species in the assemblages: Limnocythere larzacensis, Theriosynoecum aveyronensis et Fastigatocythere juglandiformis.Ostracode assemblages are characteristic of lacustrine to polyhaline and inner marine environments, and they vary according to changes in salinity, oxygen and trophic level.  相似文献   

13.
14.
Roselyne Ainardi 《Geobios》1985,18(6):693-700
Lettenkohle's lagoonal sediments of eastern Franceshow cryptalgal laminites close to diastems between two types of sequences: fluviolacustrine or «mediolittoral (french terminology, Pérès, 1966).The transition between inferior marine and middlenon-marine formations coincided with the development of stromatolitic structures, which molded and preserved the dessicated gypsiferous dolomicrites of inferior Lettenkohle.This phenomena is repeated with an inverse trend,by the way marking transition from middle to upper Lettenkohle, prior to the installation of variegated clays of inferior Keuper.  相似文献   

15.
《Médecine Nucléaire》2014,38(6):388-397
To assess the impact of standing on brain perfusion, 125 brain perfusion scans in the upright and supine position were performed, including 108 patients. Perfusion values were compared using a relative quantitative approach and a segmentation of vascular territories with the help of an atlas of brain perfusion. We found a change in the distribution of the perfusion in favor of the vertebro-basilar system in the upright position. We discuss the case of a patient whose symptoms could be explained with the help of the comparison of brain perfusion scans in the upright and supine position. Atheromatous and post-dissection stenosis and their influence on perfusion are also discussed.  相似文献   

16.
In the Western Algerian area, the Ouled Mimoun and El Rhoraf sections are particularly appropriate for the study concerning the berriasian formations.From tha lithostratigraphical point of view, the upper section of the carbonated platform corresponds to the lower Berriasian and a part of the middle Berriasian. The «Argiles de Lamoricière which dominate it belong to the middle and upper Berriasian. The subjacent detritic formation known as «Grès de Berthelot probably begins with the lower Valanginian. The stratigraphical results are based on an abundant fauna (ammonites, ostracods) collected in situ, the main species of which have been the subject of a paleontological review and abondantly illustrated.The studied series offer a good example of the evolution of sedimentary conditions which accompany the temporary opening of a carbonated platform towards the open sea.The variations in fauna composition are closely related to changes in environment. In particular, the presence of ammonites in the Boissieri zone can be connected to the highest point of marine advance, although the depth remained relatively shallow (an upper infratidal zone being likely). It is to note that during this period the low level of sedimentary activity favored the settling of some remarkable epilithic fauna.Above the «Argiles de Lamoricière, the massive detritic sedimentation (grès de Berthelot) could indicate an important paleogeographical change in the interior. In the area studied, the ostracods encountered in the basal section of the last formation still mean a shallow marine environment.  相似文献   

17.
Evolutionary lineages of several limnic gastropod genera (Viviparus, Melanopsis, Theodoxus) from the Neogene of Kos island (Dodecanese, Greece) are described and interpreted. The attempt is made to analyse the paleoecological development of a limnic sedimentary basin in the eastern portion of Kos by means of Diatoms. Obviously, there is no relation between the chemical parameters of the water of the former lake and the morphological development of the gastropods. The lineages of Viviparus brevis, Theodoxus doricus and Melanopsis gorceixi are suggested to be caused by phyletic transformations and not by changing environmental conditions. It is, thus, possible to establish a local biostratigraphy based on subspecies, and moreover, a more regional one based on longer ranging species.  相似文献   

18.
19.
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.
  相似文献   

20.
Electrograms of the thoracic pulsatile organs and of the heart during emergence and expansion of the wings have been made. The mesotergal and metatergal organs function in a similar way: active periods are interrupted by short periods of rest, but the two organs contract with different but apparently independent rhythms. During emergence and expansion, the rate of contraction of the pulsatile organs increases twofold, and the resting periods disappear during the entire period of expansion of the wings. When the wings are removed or cut short, the activity of the pulsatile organs is inhibited.  相似文献   

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