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Les bourdons constituent l’un des groupes de pollinisateurs les plus importants dans les écosystèmes montagnards. Cependant, la faune des bourdons du Parc National des Pyrénées occidentales (PNPO) est encore peu connue. Pendant trois ans, la faune des bourdons du Parc National des Pyrénées occidentales a fait l’objet d’une surveillance. Les inventaires effectués en juillet- août 2002, 2003 et 2005 ont permis l’observation de 5889 spécimens de bourdons de 29 espèces. Si l’on tient compte des observations des cinquante dernières années, la diversité spécifique du parc s’élève à 30 espèces de bourdons. Une telle diversité spécifique est remarquable et comparable à celle observée dans d’autres secteurs du massif pyrénéen. La faible différence entre les faunes du Parc et des réserves naturelles d’Eyne et de Nohèdes (Pyrénées-Orientales) rend compte du caractère exceptionnellement diversifié de la faune des bourdons du massif pyrénéen en général.  相似文献   

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Résumé Dans les glandes de la glu, formations propres aux Onychophores, les tubes sécréteurs comprennent un épithélium glandulaire entouré d'une enveloppe conjonctive et musculaire. L'enveloppe conjonctive, délimitée par des membranes basales de mucopolysaccharides neutres et de mucoprotéines, contient deux sortes de fibrilles: des fibrilles collagènes et un type particulier de fibrilles élastiques. Les fibres musculaires, éparses, d'orientation circulaire, montrent une organisation beaucoup plus rudimentaire que dans les muscles somatiques.L'épithélium glandulaire est formé de cellules prismatiques toutes semblables, à gros noyau polyploïde en position basale, avec nucléole très volumineux. L'ensemble du cytoplasme de ces cellules est chargé de ribonucléines sous forme d'ergastoplasme granulifère à citernes concentriques et de nombreux ribosomes libres. Les structures lamellaires concentriques de l'ergastoplasme, qui se différencient du côté basal, près des noyaux, s'accroissent dans la région médiane des cellules et se désorganisent à l'apex, en libérant des grandes quantités de ribosomes. La sécrétion de ces cellules est formée essentiellement de protéines qui s'accumulent dans la région apicale sans passer par l'appareil de Golgi, lequel est d'ailleurs peu développé. Ces protéines ne sont donc pas concentrées en granules de sécrétion, mais déchargées dans la cavité glandulaire, directement à l'état diffus, par l'intermédiaire d'épanchements cytoplasmiques de la face apicale cellulaire dans lesquels passent également de nombreux ribosomes libres. Polyploïdie, grand volume nucléolaire, hyperdéveloppement de l'ergastoplasme granulifère, abondance des ribosomes libres, non-intervention de l'appareil de Golgi et absence de concentration de la sécrétion en granules sont mis en relation avec la synthèse rapide et continue des protéines qui forment le principal constituant de la glu.
Cytochemical and ultrastructural data on the secretory tubes of the slime glands in Peripatus acacioi Marcus and Marcus (Onychophora)
Summary In the peculiar slime glands of the Onychophora, the secretory tubes consist of a glandular epithelium surrounded by a layer of connective and muscular tissue. The connective layer, bounded by basal membranes of neutral mucopolysaccharides and mucoproteins, contains two kinds of fibrils: collagenous fibrils and an especial type of elastic fibrils. The muscle fibers, which are scattered and circularly oriented, are more simply organized than those of the somatic muscles.The glandular epithelium is constituted by prismatic cells of the same type, with a large polyploid basally situated nucleus, containing a very large nucleolus. The cytoplasm of these cells is filled with ribonucleins in form of ergastoplasm and in numerous free ribosomes. Concentric lamellar structures of ergastoplasm, which originate basally close to the nucleus, are well developed in the central region of the cell and become disorganized at the apex, where they liberate great quantities of ribosomes. The secretion of these cells consists essentially of proteins, which accumulate in the apical region without passing through the poorly developed Golgi apparatus. These proteins, therefore, are not concentrated in secretory granules, rather they are released in a diffuse form, into the glandular cavity. They are discharged in cytoplasmic expansions detached from the apical region, together with a large quantity of free ribosomes. Polyploidy, large nucleolus, well developed granular ergastoplasm, abundance of free ribosomes, non-participation of the Golgi apparatus and lack of concentration in secretory granules are correlated with rapid and continuous synthesis of proteins which are the principal component of the slime.
Avec la collaboration technique de Mlle Eliana Parisi et l'aide de la Fundação de Amparo à Pesquisa do Estado de São Paulo.  相似文献   

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《Médecine Nucléaire》2014,38(5):299-302
Breast cancer treatment has developed rapidly for the last 15 years, promoted by a better understanding of tumour growth biology. Targeted therapies have been rapidly expending: immunotherapy, targeted chemotherapy, endocrine therapy efficacy enhanced by mTOR inhibitors. Changes of molecular profiling tumours during the illness need to perform regularly biopsies and to adapt drugs. This article will focus on a high-level overview of main advances across systemic treatment.  相似文献   

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During two sampling periods (lowflow and highflow) epilithic diatoms were collected in two hydrographic sectors of Stratonikon mountain. In the study 162 taxa were identified from which 42 species, one sub-species and nine varieties are first records for the Greek flora. Running waters present a high species richness and most of the dominant species found in the study area are cosmopolitan, alkaliphilous, prefering well oxygenated waters. The species Achnanthes minutissima var. minutissima, Amphora pediculus, Cocconeis placentula, Rhoicosphenia abbreviata, and Nitzschia dissipata var. dissipata were dominant during both sampling periods. Under highflow conditions, the species Gomphonema olivaceum var. olivaceum and G. tergestinum became also dominant. The Shannon's index values varied from 0.6 to 5.0 and evenness from 0.15 to 0.86. Dendrograms and MDS plots showed the floristic particularities of sites due to human activities and environmental conditions.The values of IPS diatomic index showed that the biological quality of the water was very good during the study period.  相似文献   

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Résumé Les auteurs ont étudié l'organogenèse des nerfs et des trachées alaires du TermiteReticulitermes lucifugus santonensis Feyt. Ils ont reconnu des organes sensoriels à processus externe appartenant à la catégorie dessensilla trichoïdea deSnodgrass, et des organes sensoriels internes (organes chordotonaux). Les premiers se rencontrent chez tous les stades de développement, alors que seules les nymphes possèdent un organe chordotonal dans leurs ébauches alaires (correspondant à l'organe tégulaire des autres Insectes).On décrit les parcours des nerfs alaires chez les larves, les ouvriers, les nymphes, les soldats, les sexués néoténiques, en soulignant les différences séparant nettement les ouvriers des nymphes. Toutefois, ces différences ne portent jamais sur le nombre des nerfs, qui est stable (nerf costal, sous-costal, radial).Tous les stades et toutes les castes (sauf les soldats) présentent trois trachées alaires (radiale, médianale et cubitale). On suppose que c'est la trachée médianale qui régresse chez les soldats.
Summary Authors study the organogenesis of alary nerves and tracheas of TermiteReticulitermes lucifugus santonensis Feyt. They describe two different kinds of sensilla:sensilla trichoïdea and chordotonal organs. The first one occurs in each caste (larvae, workers, soldiers, nymphs), but the second one is caracteristic of nymphs only (tegulary organs of others Insects).Anatomy of alary nerves is described with larvae, workers, nymphs, soldiers and neotenics. All castes have the same number of nerves costal, subcostal, radial), but workers and nymphs are easily differentiate by some characters.Each Termite has three alary tracheas (radial, medianal, and cubital) except soldiers where medianal trachea is not recognizable.
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《L'Anthropologie》2015,119(4):487-504
This paper is the state of the art of charcoal signal studies (macro-, meso- and micro-charcoal) that have been carried out at the Epigravettian settlement of Mezhyrich. This work took part of the French ANR project “Mammouths”. Charcoal signals have been found in both natural and archaeological (pits and activity areas) deposits that have been sampled during the 2007–2008 archaeological excavations. This study aims at discussing the natural versus anthropic causes of those charcoal signals. Microscopic charcoal have been observed and quantified from loess sediments; they are probably the consequence of regional fire regimes. Charcoal signals found in archaeological layers would be mainly caused by human activities. The major charcoal signal is observed within the microscopic part of the archaeological sediments and thereby underlines the intensity of taphonomic processes. The identification of wood charcoal shows that birch and willow were located along the riverbanks, which provides further discussion of prehistoric fuel management in Pleniglacial context.  相似文献   

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On the culture of spores and the development of the thallus of Botryocladia chiajeana (Menegh.) Kylin (Rhodymeniales, Rhodymeniaceae). - The complete development of Botryocladia chiajeana has been studied in culture. Spore germination and sporeling development is of the discalis mediatus type described by Inoh (1947). The hollow vesiculous branches filled with a mucilage derive from the spacing of the erect filaments which form the stipe. The authors compare this development of the thallus with that described for other Rhodymeniales.  相似文献   

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《Geobios》1988,21(3):329-357
Core samples from the Illizi basin yielded well preservedmiospores and Chitinozoa. The detailed study of the range of these microfossils allows accurate age assignment for upper Silurian and Devonian subsurface strata of the southeastern part of the algerian Sahara. On the other hand, these biostratigraphical data demonstrate the occurrence of important stratigraphical gaps related to recurrent emersions.  相似文献   

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Labelled blood cells permit nuclear medicine imaging using their physiological behaviours. The radiolabeling must be performed in vitro because of the lack of specific markers and requires several highly technical stages of preparation. Labelled blood cells have not the medication drug status, so that the nuclear physician conducting the nuclear test is fully liable. In most cases, the physician delegates the technical responsibility to radiopharmacists. Although the status of radiolabelled autologous cells is not legally defined and in the absence of a specific repository, it is essential that their preparation is subject to the requirements of the rules of French Good Manufacturing Practice published by Agence française de sécurité sanitaire des produits de santé (Afssaps). It would be desirable to harmonize the practices of radiolabeling cellular blood components by editing a repository.  相似文献   

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《L'Anthropologie》2018,122(2):87-110
In the present study, the chronology of several intraloessic Upper and Middle Palaeolithic sites, located in Moldova, Dobrogea and the eastern Danube Plain, is re-examined and better defined on the basis of new chronological data (IRSL ages on loess, ESR/U-Th ages on teeth) and also biostratigraphic and pedostratigraphic evidence. Middle Palaeolithic occupations have been identified in the MIS 6 loess L2 (interstadial episode), the MIS 7 pedocomplex S2 and the red soils S3 presumably assigned to MIS 9. These results are questioning the chronological extension of the Middle Palaeolithic in Romania which until early 2000 (Păunescu, 1999 a, b; Cârciumaru, 1999) was restricted to the Upper Pleistocene (short chronology: 130–35 ka; MIS 5-MIS 3). Hence, we demonstrate herein that Humans were already present during the Middle Pleistocene at the eastern periphery of the Carpathian Mountains, along the Danube valley and its tributary, the Prut River.  相似文献   

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《L'Anthropologie》2015,119(4):473-486
The results of palynological study of the Upper Paleolithic Mezhyrich site in central Ukraine are presented. Four local pollen zones were identified. The results of the palynological investigations allow us to hypothesize that the plant cover during Upper Paleolithic had a mosaic structure. The pollen record shows the presence of a few tree species with the predominance of herbaceous plants. We suggest that the river valleys and other local favorable sites were natural refugia where forest elements could survive even during the Last Glacial Maximum. These favorable landscapes to the existence of prehistoric hunters may have persisted during the Last Pleniglacial.  相似文献   

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Summary During the period between apolysis and ecdysis, the vesicular glands show many important transformations which affect not only the cuticular ductules, but all the cells. The cytoplasm of the glandular cells undergoes a partial autolysis, whereas other parts of the cells present a high secretory activity. Immediately after the apolysis the cellular reservoir empties and disappears almost completely; soon after, refills with secretion. The most interesting transformations concern each ciliary cell, always associated with a glandular cell. In the first phase of the moulting cycle, the dendrite of the ciliary cell grows a ciliumlike extension (= distal region of the dendrite), which penetrates into the corresponding ductule; the new intima of this ductule is laid around the cilium. At the same time, the proximal region of the dendrite forms a circular fold around the base of the cilium and begins to secrete a material which will form the end apparatus. This latter is finished during the second phase of the cycle. The third phase is characterized by the degeneration of the distal region of the dendrite and the circular fold. Thus, the end apparatus is not a secretion of the ductule-carrying cell, but of the ciliary cell. At the end of the moulting period, just before ecdysis, the vesicular gland again takes the structure characteristic of the intermoult: the reservoir of the glandular cell is very large; the cuticular apparatus is almost formed; the dendrite of the ciliary cells shows, at its apex, a short cilium (= ciliary region s. str. + short distal region) surrounded by microvilli, free in the secretion of the reservoir.  相似文献   

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Au Maroc, la famille des Encyrtidae (Hymenoptera : Chalcidoidea) compte actuellement 46 espèces. Six genres (Acerophagus Smith, 1880, Cerchysiella Girault, 1914, Cheiloneurus Westwood, 1833, Copidosoma Ratzeburg, 1844, Epitetracnemus Girault, 1915, Tineophoctonus Ashmead, 1900) et sept espèces [Cheiloneurus elegans (Dalman, 1820), Copidosoma floridanum (Ashmead, 1900), Epitetracnemus intersectus (Fonscolombe, 1832), Habrolepis pascuorum Mercet, 1921, Metaphycus melanostomatus (Timberlake, 1916), Metaphycus castaneus (Mercet, 1921) et Tineophoctonus armatus (Ashmead, 1888)] sont signalés pour la première fois de ce pays. Les échantillonnages ont été réalisés dans trois stations d’étude au sein de la subéraie de la Maâmora au cours de deux années successives (juin 2012 à avril 2014).  相似文献   

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