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A. Gilles 《Genetica》1957,28(1):42-50
Résumé Il ressort de divers essais de traitement de graines deS. Antipoviczii, par la colchicine, que la concentration optima est de l'ordre de 0,2%. La durée de l'immersion doit être d'environ 6 heures, s'il s'agit de graines prégermées; de 5 à 6 jours, s'il s'agit de graines sèches. Des observations analogues ont été faites, après traitements semblables, chezS. verrucosum etS. longipedicellatum.Le traitement, dans les conditions précitées, de graines deS. tuberosum, variétés Flava et Katahdin, a donné des plantes octoploïdes réduites, à feuilles coriaces, à pigmentation très foncée, terminalement ramifiées (Flava) ou non ramifiées (Katahdin); elles se sont montrées entièrement stériles pendant deux années consécutives, après avoir végété pendant 9 à 10 mois; leurs tubercules sont petits et peu nombreux.
Recherches subsidiées par le Fonds National de la Recherche Scientifique (Crédits aux Chercheurs). 相似文献
Summary Various colchicine treatments of seeds, inS. Antipoviczii, have shown that the optimum concentration of the solution is 0,2%. Pre-germinated seeds should be soaked for about 6 hours and dry seeds 5 or 6 days, as is indicated through cytological analysis at various steps of the treatment. The same result have been obtained withS. verrucosum andS. longipedicellatum.After such a treatment, octoploids plants ofS. tuberosum var. Flava and var. Katahdin have been produced, which remain small and form thick dark-green leaves; the stem is thick, but very flexible, with dense terminal ramification (Flava) or without ramification (Katahdin). They produce a few small tubers but are completely sterible; in 1953 and in 1954, no flower has appeared even after a vegetative period of 9–10 months each year.
Samenvatting Een vergelijking van verschillende colchicine-concentraties, waarin zaden vanSolanum antipoviczii geweekt werden, heeft aangetoond dat de optimum-concentratie van de oplossing 0.2% bedraagt. Voorgekiemde zaden verlangen een onderdompeling van ongeveer zes uur, droge zaden vereisen vijf tot zes dagen, zoals bleek uit een cytologische analyse op verschillende tijdstippen tijdens de behandeling. Dezelfde resultaten werden verkregen metS. verrucosum en metS. longipedicellatum.Na zulk een behandeling werden octoploide planten vanS. tuberosum var. Flava en var. Katahdin verkregen, welke planten klein blijven en donkergroene, leerachtige bladeren vormen; de stengel is dik, maar goed buigbaar, met een dichte terminale vertakking (Flava) of onvertakt (Katahdin). Deze planten bleken twee jaar lang (1953 en 1954) volkomen steriel te zijn, in deze zin, dat ze na een vegetatieve groeitijd van 9–10 maanden niet tot bloei zijn gekomen. Wel produceerden ze talrijke kleine knolletjes.
Recherches subsidiées par le Fonds National de la Recherche Scientifique (Crédits aux Chercheurs). 相似文献
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P. Jouannet 《Andrologie》2012,22(1):10-19
The incidence of testicular cancer (TC) has a distinct geographic distribution but is increasing in most countries, including France. The most likely origin of TC is a lack of normal germ cell differentiation in the foetal testis. The maintained immature germ cells could proliferate after puberty to induce testicular tumor. Because of its frequent association with cryptorchidism and infertility, TC could be part of the testicular dysgenesis syndrome. The role of genetic factors is suggested by the frequency of familial TC cases, but no responsible gene has been clearly identified until now. Among the various studied genes, those regulating the KITLG/KIT pathway involved in primordial germ cell proliferation seem to play an important role. Studies made in immigrants and twins suggest the influence of environmental factors on the origin of TC. Hormonal deregulation occurring during prenatal life or puberty could facilitate the development of TC. However, the role of exogenous substances acting as endocrine disruptors has not been demonstrated yet. 相似文献
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Eliane Didier 《Development genes and evolution》1973,172(4):287-302
Résumé L'analyse de certains points de la morphogénèse du canal de Müller et du rôle joué par le canal de Wolff dans la formation de l'oviducte a été abordée à l'aide de diverses méthodes expérimentales (blocage de l'ébauche müllérienne par un obstacle mécanique ou par une irradiation localisée par les rayons X).Les résultats obtenus soulignent la formation et l'évolution indépendante des 2 tissus, l'epithélium interne et le mésenchyme périphérique, qui composent la jeune ébauche müllérienne.L'épithélium interne se met en place par le jeu de la croissance crânio-caudale d'une ébauche primitive formée au niveau de l'ostium et induite par le canal de Wolff.Le mésenchyme périphérique se forme «in situ», aux dépens de la crÊte mullérienne qui est elle-mÊme induite par le canal de Wolff.Chez les Oiseaux, le développement de l'oviducte reste donc dépendant de l'uretère primaire, du fait de la double action inductrice exercée par le canal de Wolff sur les deux tissus constituant primitivement le canal de Müller.
Researches on Mullerian duct morphogenesis in birdsII. Experimental study
Summary Certain points in the Mullerian duct morphogenesis, and the role played by the Wolffian duct in oviduct formation, were studied with some experimental methods (by stopping the mullerian anlage with a mechanical obstacle, or by a localized irradiation with X-rays).The results emphasize the independent formation and evolution of the two tissues, the inner epithelium and the mesenchyme which compose the young mullerian anlage.The inner epithelium is formed by the cranio-caudad outgrowth of a primitive anlage, formed at the level of the ostium, and induced by the Wolffian duct.The peripheric mesenchyme is formed in situ, from the mullerian strip, which itself is induced by the Wolffian duct.In Birds, oviduct development depends upon the primary ureter, by means of the double inductive action exerted by the Wolffian duct upon both tissues constituting the Mullerian duct anlage.相似文献
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Salvatore Gentile 《Plant Ecology》1969,17(1):214-231
Summary On the basis of the observations and the records presented, it is remarked that in the Southern Apennines and in Sicily the forests ofQuercus ilex are prevalently localised in the altimetrical band included between 650–700 and 900–950 m. But the greater extension is rejoined in the band from 800 and 950 m. This limitation above and especially below those levels is to be considered actual and caused only by man.The examination of the flowering records permits the arrangement of the forests ofQuercus ilex of the Southern Apennines and Sicily in a new association: the Querco-Teucrietum siculi, that here seems the only representative also of the Quercion ilicis. It borders upon the associations of the Oleo-Ceratonion in the lower part and upon those of the Quercion pubescentipetraeae in the higher part and often immediately with those of the Fagion. The elements of the physical environment of the present and potential surfaces of the association are distinguished in geological-pedologicals and climatics. The substratum pedogenetic is very variable therefore it doesn't seem determinant for the normal development of the Querco-Teucrietum siculi. The factors of the climate result instead determinant. At the lowest levels the limit is formed by the temperatures too high and the excessive drought. At the highest levels the limitant element is especially formed by the high atmospherical dampness, especially in the form of fogs. It is said that the association finds favourable conditions
Zusammenfassung In den S-Apenninen und Sizilien sind die Steineichenwälder heute größtenteils auf Streifen zwischen 650–700 und 900–950 m begrenzt und zwischen 800–950 m am reichlichsten. Diese Wälder werden in eine neue Ass., das Querco-Teucrietum siculi, eingeordnet, das dort wahrscheinlich der einzige Vertreter des Quercion ilicis ist. Es grenzt unten immer an das Oleo-C eratonion und oben an das Quercion pubescenti-petraeae und oft auch unmittelbar an das Fagion.Das Substrat bringt keine großen Veränderungen im floristischen Gefüge und übt keinen Einfluß auf die Verteilung der Ass. aus. Die Klimafaktoren sind für Areal und Höhenverteilung bestimmend. Bei geringsten Höhen bilden die sehr hohen Temperaturen und die übermäßige Trockenheit einen einschränkenden Faktor. Bei den obersten Höhen besteht der wichtigste, einschränkende Faktor aus einer sehr erhöhten Luftfeuchtigkeit und sehr häufigen Nebeln. Die Gesellschaft findet günstige Bedingungen im zwischen den Regenlinien von 600 und 900–1000 mm liegenden Bezirk, bei Trockenheitsindex nachde martonne um 25–35. Das Assoziationsareal wurde noch nicht bestimmt und so bleiben die dynamischen Serien noch teilweise unbekannt.Das Bodenprofil besteht aus Horizonten A/C. Wahrscheinlich handelt es sich um mediterrane Braunerde des xerophilen Waldes.Ökologisch liegt die neue Gesellschaft zwischen dem Quercetum ilicis galloprovinciale (das durch Assoziationen des Oleo-Ceratonion ersetzt wird) und dem Quercetum mediterraneo-montanum; beide sind aber vielleicht in den S-Apenninen nicht vorhanden.
Riassunto In base alle osservazioni ed ai rilevamenti presentati, si constata che nell'Appennino meridionale ed in Sicilia le Leccete sono localizzate prevalentemente nella fascia altimetrica comprese fra 650–700 e 900–950 m. La maggiore estensione però viene da esse raggiunta in una fascia più stretta, compresa fra 800 e 950 m. Al di sotto delle quote inferiori menzionate la limitazione è tuttavia da considerare per lo più solo attuale e determinata dall'uomo.L'esame dei rilevamenti floristici consente l'inquadramento delle Leccete suddette in una nuova associazione, il Querco-Teucrietum siculi, che per l'Appennino meridionale e la Sicilia può essere considerata l'unica rappresentante del Quercion ilicis. Essa confina in basso con l'Oleo-Cerationon ed in alto con il Quercion pubescenti-petraeae, o spesso direttamente con il Fagion.I fattori dell'ambiente fisico riferibile all'associazione vengono distinti in geo-pedologici e climatici. Il substrato pedogenetico è molto variabile, dunque non sembra influenzare apprezzabilmente il suo corteggio floristico normale, nè limitarne l'estensione. Più importanti risultano invece i fattori del clima. Alle quote più basse il limite è costituito dalle temperature troppoelevate e da una eccessiva siccità. Alle quote più alte il fattore limitante più importante sembra essere costituito da una umidità atmosferica abbastanza elevata, specialmente sotto forma di nebbie. Quanto alle precipitazioni, si può dire che l'associazione trova condizioni favorevoli di svilluppo nell'area compresa fra le isoiete di 600 e 900–1000 mm; qui l'indice di aridità diDe Martonne si aggira sui valori di 25–35, o poco più.L'area geografica dell'associazione non viene per il momento definita. Anche le serie dinamiche ad essa collegate restano ancora parzialmente sconosciute.Il profilo del suolo può essere considerato di tipo A/C. Le sue caratteristiche fanno pensare alla terra bruna mediterranea della foresta xerofila.In base alle sue caratteristiche, sopratutto ecologiche, il Querco-Teucrietum siculi può essere considerato intermediario fra il Quercetum ilicis galloprovinciale (qui rimpiazzato da associazioni dell'Oleo-Ceratonion) ed il Quercetum mediterraneo-montanum, entrambe probabilmente mancanti nell'Appennino meridionale.相似文献
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Résumé L'AGCD gère 60% de l'aide publique belge au développement. Celle-ci consiste essentiellement en l'envoi de personnel belge qualifié ou d'experts, en l'apport d'équipement et de matériel, en le financement d'études ou en la formation de cadres locaux. En pratique l'AGCD travaille soit en responsabilité directe soit en collaboration avec des institutions spécialisées, universités, centres de recherche, organisations non gouvernementales ou internationales. De plus l'AGCD dispose de moyens d'intervention de type financier tels que le Fonds des Prêts à des Etats Etrangers et le Fonds de la Coopération au Développement.
Summary The Belgian Administration for Development Cooperation (AGCD) is responsible for 60% of the Belgian public cooperation with Developing Countries. In addition to the standard means of cooperation like training, fellowships, Belgian experts, feasibility studies, donation of equipment and materials, etc., AGCD has been recently given two new instruments of cooperation, namely: the Fund for Loan to Foreign Countries and the Fund for Development Cooperation. Thanks to these new instruments AGCD is now in a position to assist by offering concessional loans, by participating in the equity of state-owned companies and by granting credit lines to national development banks. In the field of anaerobic digestion AGCD is presently undertaking two main projects: one in Burundi with the University of Louvain-la Neuve and another in Indonesia with the University of Ghent. It also co-finances punctual initiatives of non-governmental organisations and is finalizing the negotiations for the Belgian contribution to the World Bank Energy System Management Assistance Programme (better known as the ESMAP). Furthermore, Belgium is preparing a cooperation programme jointly with the World Bank to promote the biomethanation of organic domestic refuse.
Resumen La Administración General de Cooperación para el Desarrollo es responsable del 60% de la cooperación belga con países en desarrollo. Además de los sistemas tradicionales de cooperación tales como ayudas para formación, becas, profesionales belgas, proyectos, donación de equipo y materiales, etc. se ha dotado recientemente a la AGCD con dos nuevos instrumentos de cooperación, más concretamente: la Fundación de Crédito a países Extranjeros y la Fundación para la Cooperación al Desarrollo. Gracias a estos nuevos instrumentos la AGCD puede ahora ofrecer asistencia mediante la concesión de prestamos, participando en la gestión de empresas públicas y asegurando lineas de crédito para los bancos nacionales de desarrollo. En el area de la digestión anaerobia la AGCD tiene dos proyectos en curso: uno en Burundi en colaboración con la Universidad de Louvain-la-Neuve y otro en Indonesia con la Universidad de Ghent. La AGCD también co-financia iniciativas puntuales de organizaciones extra gubernamentales y esta en vías de finalizar las negociaciones para determinar la contribución belga al programa del Banco Mundial de asistencia para la gestión de recursos energéticos (conocido como ESMAP). Belgica esta además preparando un programa de cooperación con el Banco Mundial para promover la biometanación de desechos orgánicos domésticos.相似文献
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With the help of a questionnaire, we assessed the impact of circumcision, practiced on adult patients for various indications, on sexually transmitted diseases (STD) and sexuality. Recurrent or obstinate STD represented the most frequent indication (75%). Subsequentely almost 96% of the patients declared to be satisfied with their sexuality and nearly 80% did not mention any recurrence of their disease. 相似文献