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1.
The first brackish levels of the Aquitanian (s. lat.) of Cap Janet (B. du Rh.), contemporaneous with thoseof Carry-le-Rouet, have provided rodents and continental molluscs. They belong to the same level as the mammals of Coderet and so are correlated to the “série grise” of Barrême, the “calcaire de Reillanne”, the marls and limestones of Rougier, the gypsun of Aix. Older faunas found in the localities of “St-Henri” and “Les Milles” show that they belong to the same detritic flow as the “marnes de Viens”.  相似文献   

2.
M. Brunet  Y. Jehenne  M. Ringeade 《Geobios》1977,10(1):109-112
The new locality of Ruch (Gironde), from a lateral facies of the “Calcaire de Castillon” formation has yielded an important flora and fauna. From the biostratigraphic point of view the mammalian fauna allows to show that Ruch is contemporaneous of the reference locality of Ronzon (Auvergne).  相似文献   

3.
The so-called “série carbonatée” of Aurillac-Arpajon basin is generally ascribed to the upper Oligocene; a newlydiscovered micrommalian fauna shows that the basis of this sequence is really older and at least of a middle oligocene age.  相似文献   

4.
Jean-Louis Henry 《Geobios》1976,9(5):665-671
In the Massif Armoricain, Kerfornella nov. gen. includes several trilobites from the Llanvirn and the Llandeilo:K. brevicaudata (DESLONGCHAMPS) and K. cf. brevicaudata in Normandie, K. miloni nov. sp. and K. nov. sp. aff. miloni in the Synclinorium median. All these species, previously attributed to Plaesiacomia ? brevicaudata (DESLONGCHAMPS), would belong to two distinct phyletic lines. The stratigraphical interest of K. brevicaudata, which occurs in the Lower Grès de May and in the “quartzites Botella” from eastern Sierra Morena, is confirmed.  相似文献   

5.
RÉSUMÉ. Des expérimentations portant sur des cellules isolées ont montré que 77% des microstomes de Tetrahymena paravorax, prélevés au hasard dans des cultures en phase logarithmique de croissance, se transforment directement en macrostomes en présence de “stomatine.” Ces macrostomes apparaissent à des moments variés entre 1,5 et 9 h après l'addition de la stomatine (“point 50% de transformations” vers 2,5 h). La compétence pour le remplacement oral est en relation avec la position dans le cycle cellulaire. Les pourcentages de transformation les plus élevés sont observés avec les populations testées pendant la première moitié de la période moyenne d'interfission. La formation des macrostomes est d'autant plus rapide que l'ǎge initial des microstomes est plus proche du point médian du cycle cellulaire (“point de compétence”). Dans la seconde moitié de ce cycle, le temps moyen de transformation reste à peu près constant, mais le pourcentage de divisions augmente: le “point de transition” (50% de divisions) se trouve au début d'une phase terminale représentant 19–20% de la durée totale du cycle. La transformation des produits de bipartition antérieur et postérieur est nettement asynchrone: dans la majorité des paires cellulaires, l'opisthe se transforme avant le proter. Les cellules-soeurs se divisent aussi de manière asynchrone: le temps de génération du proter est plus long que celui de l'opisthe. Le problème de l'acquisition de la compétence pour le changement de phénotype est discuté en envisageant les corrélations éventuelles avec certains processus majeurs du cycle cellulaire. SYNOPSIS. Seventy-seven percent of the microstomes of Tetrahymena paravorax taken from random samples of log-phase cultures transform directly into macrostomes in the presence of “stomatin.” These macrostomes appear between 1.5 and 9 h after addition of stomatin (“50% transformation point,”~ 2.5 h). Competence for oral replacement is related to the position in the cell cycle. The highest percentages of transformation are observed in populations tested during the first half of the mean interfission period. Formation of macrostomes is more rapid when the initial age of the microstomes is nearer to the midpoint of the cell cycle (“competence point”). In the 2nd half of this cycle, the mean transformation time remains approximately constant, but the percentage of cells undergoing division is increasing. The “transition point” (50% divided cells) is found at the beginning of a terminal phase which accounts for 19–20% of the cell cycle. Transformation of anterior and posterior fission products is fairly asynchronous; in the majority of individual pairs, the opisthe is transformed before the proter. The daughter cells also divide asynchronously, the generation time of the proter being longer than that of the opisthe. The problem of acquisition of competence for phenotypic change is discussed in light of possible correlations with certain major processes of the cell cycle.  相似文献   

6.
7.
The lack of hinge spines on the left side of the ventral valve in Chonetacea is demonstrated here for the first time. This morphological peculiarity has a special bearing on the evolutionary trends of the Strophochonetinae. The existence of several species of Chonetacea, both in the Armorican Massif, the Cantabrian Mountains, and Aragon, is a new fact which confirms very close relations between these three areas during Lower Devonian times.  相似文献   

8.
Only one piece of liassic ammonite is known in Corsica (SE of St. Florent in the “unité of Tuda”). It is a Arietitidae, probably Paltechioceras or Vermiceras (top or bottom of Sinemurian). The Lias of Tuda, similar to that of “écailles de Corté”, belongs to parautochtonous external realm.  相似文献   

9.
Within the framework of the European Commission's program “Patine du Desert” (DG Research; INCO-CT-FP6-2004-509100), partially concerning the preservation of Saharan engraved rock art, the approach led to the study of the sandstone patina from the rock art site of Oum La Leg (Anti-Atlas, Morocco). The rock and its Tazina school engravings are sometimes covered with a thin brown-ochre coating which only shows a dark patina, the desert patina. This film corresponds to a weathering cortex whose formation is contemporary with wet events from the Holocene period. On the surface, the patinas’ diversity is linked to the heterogeneous distribution of manganese oxides (birnessite and todorokite) due to a reorganisation which led to the incorporation of aeolian silts. Some dating suggestions are made to establish an ante quem age for the engraved lines.  相似文献   

10.
Francis Lethiers 《Geobios》1975,8(2):135-138
The Entomozoïd Ostracods are deemed pelagic. Their occurrence is world wide. In the Ardennes, the only “faciès Matagne” of the Upper Devonian includes a lot of these Ostracods the main species of wich are listed here. Either environment of life or fossilization, or both of them are responsible of this localization.  相似文献   

11.
This article discusses and essential aspect of the link between ethics and life, as expressed in the concept of bioethics. It discusses the various issues related to human reproduction from “the philosopher’s point of view”. This discussion is limited to the principles of this field. The author starts by justifying a philosophical approach to ethical problems in the context of medicine in general and reproduction in particular, a field which specialists, theoreticians or practitioners of medicine and legal medicine in particular, appear to have ignored. This leads to a discussion of the human aspects of reproduction, from questions concerning the nature of living beings (individuals and species) to the relationship between nature and culture (symbol and freedom). Although man “reproduces” and “procreates”, he is also technically able to “produce himself”. This shift from biological reproduction to procreation must take into account problems related to technological science in medicine (technical control of living material and so-called “neutrality” of the technique). The main bioethical issues involving an ethics of decision-making in the field of human reproduction (contraception, abortion, status of the embryo, medically-assisted procreation, desire to master the “form” of the “reproduced” human, or even the “product”, cloning) are then discussed. Finally, the author proposes elements of a “philosophy of point of view”, requiring responsibility for each decision in the context of an “ethics of discussion”.  相似文献   

12.
The symptom of impotence is, in the vast majority of cases, extremely welldefined. However, therapeutic approaches incorporate various strategies, including: andrological, analytical and behavioural. A great advance in recent years was due to the development of “integrative models” such as the “American Model” by Helen Kaplan, the “Geneva Model” of Willy Pasini, and our proposed “Parisian Model”, which is founded on the principles of analytical sexotherapy, and comprises several clearly defined stages. The management of impotence must not be restricted only to pharmacological treatment.  相似文献   

13.
At Verzenay, in the Reims area, the upper part of the “Lignites du Soissonnais” have been turned into a paleosol. A petrographical and geochimical study of this profile allow us to see there a fossilized mangrove soil.A palynological study carried out on the same samples shows typical taxons of the mangrove environment (Nypa, Bruguiera, Acrostichum aureum). Then, palynological results perfectly agree with the sedimentological interpretation.  相似文献   

14.
Parkinsonids (Ammonitina) of the Subfurcatum Zone (Upper Bajocian) were found in the “Calcaires à petites huitres” formation from the northern part of Ile Crémieu. Correlations are established between different Upper Bajocian lithostratigraphic units of Mont d'Or lyonnais, Ile Crémieu and folded Jura.  相似文献   

15.
B. Pachoud 《PSN》2010,8(3):152-157
The debate about care and its different forms has developed a lot in social sciences and in moral philosophy, since Carol Gilligan, arguing in a feminist perspective against the prejudices of moral development psychology, has defined an “ethics of care” and claimed that it should be recognized as of the same value as the dominant ethics (Kantian or utilitarian). Following this claim, a variety of researches have been carried out concerning the activity of caring that goes beyond the field of medical practice. However, in the medical field, in which “care” has to be distinguished from “cure,” the development of a theory of care has a strong impact on the conception of treatment (of its organization, its assessment, and the way it is taught). We will focus particularly on what is implied in psychiatry by such a characterization of care.  相似文献   

16.
The article examines why evolutionary biologists have been haunted by the question whether they are “Darwinian” or “non-Darwinian” ever since Darwin's Origin of species. Modern criticisms addressed to Darwinism are classified into two categories: those concerning Darwin's hypothesis of “descent with modification” and those addressed to the hypothesis of natural selection. In both cases, although the particular models that Darwin proposed for these two hypotheses have been significantly revised and expanded, Darwin's general framework has constrained and canalized evolutionary research, in the sense that it has settled an array of possible theoretical choices. Gould's changing attitudes regarding Darwinism is taken as a striking illustration of this interpretation.  相似文献   

17.
In rotifer communities of two french peat-bogs, characteristic species associations can be described for each stage in the formation of this ecosystem. The oligotrophic lowmoor with Sphagnum angustifolium has the highest proportion of characteristic species.The affinity between the open water fauna (used as a standard) and the Sphagnum fauna decreases with a gradient in water content. The latter was a dominant factor in the distribution of rotifer species in the peat-bog.
Répartition des rotifères dans deux lacs-tourbières du Massif Central (France)
  相似文献   

18.
L'infraciliature ventrale est presque entièrement détruite lors de la conjugaison: la totalité des structures buccales, tous les cirres fronto-ventraux et transversaux, certains cirres caudaux. Le retour à l'état végétatif s'effectue en 2 étapes. Première Etape.–Différenciation d'un nouvel ensemble de cirres, dépourvu du cirre 1/I (selon la nomenclature de Wallengren); néoformation, à partir d'une ébauche située sur le territoire présomptif du cirre manquant, d'une partie des structures buccales (la moitié antérieure de la frange adorale de membranelles). Deuxième Etape.–Remplacement de tous les cirres par un nouvel ensemble comportant le cirre 1/I; différenciation des structures buccales manquantes (moitié postérieure de la frange adorale, ciliature parorale) Les rapports morphogénétiques entre le cirre 1/I et la ciliature parorale suggèrent que le territoire de ce “cirre paroral” est homologue des territoires stomatogènes d'autres Hypotriches tels que Kahliella et Stylonychia. SYNOPSIS. During conjugation of Euplotes, the ventral ciliature, including the entire oral apparatus, all the fronto-ventral and transverse cirri, and some of the caudal cirri, is nearly completely lost. As followed in silver-stained preparations, the redifferentiation of the ciliature proceeds in 2 steps. The first step entails differentiation of a new complement of cirri, except for cirrus 1/I (according to the nomenclature of Wallengren), and neoformation of the anterior part of the adoral zone of membranelles (AZM) from a primordium located in an area that would be expected to give rise to the missing 1/I cirrus. The 2nd step involves replacement of all the cirri, including 1/I, and completion of the oral apparatus by redifferentiation of the posterior half of the AZM and of the paroral ciliature. The spatial morphogenetic relationships between cirrus 1/I and the paroral ciliature suggest that the area of this “paroral cirrus” is homologous with the stomatogenic areas of other Hypotrichida, such as Kahliella and Stylonychia.  相似文献   

19.
《L'Anthropologie》2015,119(1):72-88
It is generally accepted that the metal appeared in Morocco under Iberian influence during the second millennium BC (3800–3200 BP). On the base of three main types of “peltiforme” axes represented in rock engravings, we assume the existence of an endogenous and independent invention of metallurgy in southern Morocco. Initially, we will discuss the chronological implications of this proposal, which will be then confronted with historical and ethnological data. Several factors support the hypothesis that a black population of nomadic hunters was established on the north bank of the Moroccan Sahara. This population probably assimilated by paléoberbère society from the late Neolithic would be the inventor of the “Metgourine” axe and Metallurgy. Such a hypothesis is supported by a set of arguments from various disciplinary fields.  相似文献   

20.
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