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1.
Annick Isaia 《Planta》1971,96(2):175-182
Summary The activities of (±)-abscisic acid and a number of compounds derived from p-coumaric acid and coumarin and their interaction with gibberellic acid in the control of the elongation of the first wheat leaf are examined. (±)-Abscisic acid strongly inhibits leaf growth in the presence as well as in the absence of gibberellic acid, but the inhibition is greater in the presence of gibberellic acid (3 g/l already have an observable effect). Among other compounds, only ferulic acid and coumarin significantly reduce leaf elongation, and they are effective only at high concentrations (1.44 · 10-4 M/l). 相似文献
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The cytokinin activities of various 6-acylaminopurines, 6-alkylaminopurines, 6-acylamino-9-benzyl-purines as well as a series of isosteric-nitrogen derivatives of N6-(γ, γ-dimethylallyl)adenine (I6Ade) have been tested using the tobacco pith and the pea bud bioassays. The interactions between active, slightly active and inactive compounds have been studied with the last assay. Acylation decreases the biological activity; e.g., N6-benzoyl and N6-furoyladenines are less active than Na6-benzyladenine and kinetin. Substitution at the 9-position reduces (tobacco-pith assay) or suppresses (pea-bud assay) the phytohormonal activity of otherwise active 6-acylaminopurines. In isosteric derivatives, maximum activity occurs when the side chain has the same length as in 16Ade. After the analysis of interactions between more or less active compounds, it is suggested that the differences in cytokinin activity could be related to unequal affinities for a hypothetical receptor site. 相似文献
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J. Hourdry 《Histochemistry and cell biology》1971,26(2):142-159
Résumé Dans l'épithélium intestinal de la larve du discoglosse, nous avons recherché par le microscope électronique les activités de trois enzymes lysosomiques: la phosphatase acide, la thiolacétate-estérase et l'aryl sulfatase.Avant le climax de la métamorphose, l'activité phosphatasique acide se localise dans des corps au diamètre inférieur au micron, présents dans la zone supranucléaire de l'épithélium primaire. Durant la période climacique (émergence du premier membre antérieur), le produit de réaction diffuse depuis ces lysosomes et occupe le hyaloplasme environnant. Des aires d'autolyse aux limites imprécises apparaissent alors dans l'épithélium. A leur voisinage, on reconnaît de nombreuses vacuoles autolytiques, aux dimensions variées et en général phosphatase acide-positives; elles sont accompagnées de leurs formes d'évolution (corps résiduels) enrichis en tourbillons membranaires; les plus grandes de ces vacuoles pourraient naître après encerclement des aires d'autolyse diffuse. En fin de climax, le phosphate de plomb envahit tout le hyaloplasme, cependant que des fragments cellulaires dégénérés se remarquent dans la lumière de l'organe. Au contraire, l'épithélium secondaire de remplacement est toujours dépourvu du produit de réaction.La mise en évidence des activités thiolacétate-estérasique et aryl sulfatasique confirme la nature lysosomique des corps supranucléaires et des vacuoles autolytiques de l'épithélium primaire.
Histochemical study of some lysosomal hydrolases of the intestinal epithelium during the development of the tadpole of Discoglossus pictus otth, anuran amphibianII. Observation with the electron microscope
Summary In the intestinal epithelium of the tadpole of the discoglosse, we have analysed the activities of three lysosomal enzymes: acid phosphatase, thiolacetate-esterase and arylsulphatase with the electron microscope.Before the climax of the metamorphosis, the acid phosphatase activity is localized in bodies smaller to one micron in diameter, which are observed in the primary epithelium supranuclear cytoplasm. During the climax (emergence of the first fore-leg), the reaction product diffuses itself from these lysosomes and occupies the surrounding hyaloplasm. Then, autolytic unprecise-limited areas appear in the epithelium. In their neighbourhood, many, more or less large and acid phosphatase-positive, autolytic vacuoles are recognized; they are surrounded by their residual bodies enriched with membrane whorls; the larger vacuoles might appear after segregation of diffuse autolytic areas. At the end of the climax, the lead phosphate invades the whole hyaloplasm; in the meanwhile, cellular degenerated bits are to be seen in the intestinal lumen. On the contrary, the secondary epithelium replacing the primary is always devoid of the reaction product.The visualization of the activities of thiolacetate-esterase and arysulphatase confirms the lysosomal nature of the supranuclear bodies and the autolytic vacuoles of the primary epithelium.相似文献
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《L'Anthropologie》2019,123(3):485-667
The protohistoric rock engravings of the region of Mount Bego, located in the Alpes-Maritimes, in the municipality of Tende, include more than 40,000 figurative engravings, such as corniforms, daggers, halberds, axes, reticulates, appendage reticulate, rectangular or oval beaches, anthropomorphs, geometric figures and radiant circles that we consider as an ideogram and more than 60,000 non-figurative signs, such as isolated cupules, isolated cupules of cells, small beaches of cupules, scattered clouds of cupules, bars, which although not figurative are all highly significant. All these engravings, inscribed on more than 4150 rocks spread over 1500 hectares, in eight high mountain valleys, most often made with small cups, were not carried out at random. They have been traced in relation to economic concerns, cosmogonic myths and cultural traditions of the farming and pastoral peoples of the Copper Age and the Early Bronze Age of the Southern Alps during propitiatory rites. It was a period corresponding to the climatic optimum of Chalcolithic where during the summer, in the lower valleys, cultivated fields and pastures dried up. The economic preoccupations of the populations who then occupied the regions located on both sides of the Southern Alps were essentially turned towards the search for water to irrigate cultivated fields and pastures, as evidenced by the petroglyphs inscribed on the rocks: sinuous lines evoking creeks or irrigation canals, rectangular or oval beaches, water catch basins, isolated wells, isolated wells, wells or scattered cups of rain or reticulates, which represent cultivated fields and pastures connected to natural holes or cracks that evoke springs and streams. During propitiatory rites, the engravers addressed the god of the storm, master of the lightning and dispenser of the fertilizing rain, to the great goddess, goddess-mother or goddess-Earth, arms raised in a position of receptivity for collect rain from the sky and bring in spring, with the return of vegetation, abundance to humans. 相似文献
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J. Hourdry 《Histochemistry and cell biology》1971,26(2):126-141
Résumé Nous avons étudié au microscope photonique les activités de cinq enzymes lysosomiques de l'épithélium intestinal, lors du développement larvaire d'un Amphibien Anoure, Discoglossus pictus Otth. Nous avons visualisé ces activités par le sulfure de plomb (phosphatase acide et thiolacétate-estérase), le sulfate de baryum en contraste de phase (aryl sulfatase) ou par un colorant azoïque (phosphatase acide, -glucuronidase et N-acétyl--glucosaminidase). Avant le climax de la métamorphose, le produit de réaction reste localisé à de petits granules de l'espace supranucléaire. Il envahit l'épithélium primaire au moment du climax (émergence du premier membre antérieur), durant lequel cette assise subit une histolyse. Ce produit est alors présent dans de nombreux corps aux dimensions élevées, assimilables à des cytolysomes (vacuoles autolytiques) ou à des cellules altérées; parfois on le décèle à l'état diffus dans le hyaloplasme. L'épithélium secondaire qui se substitue au primaire ne montre en général aucune activité enzymatique. L'intensité de la réaction varie aussi selon l'enzyme; en particulier, elle demeure faible pour la -glucuronidase mais élevée pour la N-a--glucosaminidase.
Histochemical study of some lysosomal hydrolases of the intestinal epithelium during the development of the tadpole of Discoglossus pictus Otth, anuran amphibianI. Observation with the light microscope
Summary We have studied with a light microscope the activities of five lysosomal enzymes of the intestinal epithelium, during the development of the tadpole of an Anuran Amphibian, Discoglossus pictus Otth. We have visualized these activities by lead sulfide (acid phosphatase and thiolacetate-esterase), barium sulphate with a phase contrast microscope (arylsulphatase) or by an azo-dye (acid phosphatase, -glucuronidase and N-acetyl--glucosaminidase). Before the climax of the metamorphosis, the reaction product is localized in little granules of the supranuclear cytoplasm. It invades the primary epithelium during the climax (emergence of first fore-leg), while a histolysis of the primary epithelium can be observed. Then this product can be seen in many large bodies which can be explained as cytolysomes (autolytic vacuoles) or as disorganized cells; sometimes too, it can be found in the hyaloplasm. Generally, the secondary epithelium which takes the place of the primary one does not show any hydrolytic activity. The intensity of the reaction also varies with the enzyme; in particular, it remains slight with the -glucuronidase but high with the N-a--glucosaminidase.相似文献
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《Comptes Rendus Palevol》2019,18(3):390-406
The historian, archaeologist, and naturalist Charles de Gerville (1769–1853) reported as early as January 1816 the presence of fossil bones in the quarries of the region of Valognes, in the department of Manche. These quarries exploited the “Calcaire de Valognes” and the underlying “Argiles et Calcaires d’Huberville”, both formations dated as Lower Hettangian (Lower Jurassic). De Gerville communicated to Jacques-Louis-Marin Defrance a watercolour drawing of one of these fossil bones, discovered in July 1820, in which it is possible to recognize a plesiosaur femur. This femur, as well as a fragment of rib and three vertebrae of Plesiosauria from de Gerville's collection, was then figured in a publication by Arcisse de Caumont, in 1825. The plesiosaur femur was later acquired by Pierre Tesson of Caen, who owned one of the most important collections of fossils in Normandy. The Tesson collection was later purchased in 1857 by the British Museum (now The Natural History Museum, London), where the femur has been rediscovered. This specimen is the first known plesiosaur specimen ever discovered in the Lower Jurassic of France, before the genus Plesiosaurus was established upon material from the Lias of southwestern England. One of the vertebrae figured by de Caumont has been rediscovered in the “Muséum Emmanuel-Liais” (Cherbourg-en-Cotentin), which had acquired part of de Gerville's collection. The interpretation of the “fossil bones of Valognes” by Georges Cuvier, Henri Marie Ducrotay de Blainville, Arcisse de Caumont, Jacques-Amand Eudes-Deslongchamps and Constant Duméril is revealed through unpublished documents. 相似文献
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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
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Abdoulaye Kassoum Kone Adama Zan Diarra Maimouna Coulibaly Sirama Niaré Michel Berthe Abdourahamane Traoré 《法国昆虫学会纪事》2016,52(2):95-101
Au Mali la leishmaniose cutanée (LC) est bien décrite en milieu rural, mais sa transmission n’est pas encore établie en milieu urbain. L’objectif de l’étude était de décrire la faune phlébotomienne à Bamako et dans ses environs. Les pièges CDC et adhésifs servaient à collecter les phlébotomes en 2011 et 2012 à Bamako. Les pièges étaient placés dans le district de Bamako répartis en 30 zones (200 m × 200 m) à l’aide des images de satellite SPOT-5. La délimitation des zones était basée sur les facteurs écologiques (relief, hydrographie, couverture végétale) et anthropologiques (nature des maisons, dépôts d’ordure). Les pièges étaient placés en 2011 à Sotuba, zone périurbaine, puis à Donéguébougou et Banambani, deux villages environnants de Bamako. Au total 122 phlébotomes étaient collectés 27 (22,13 %) à Banambani, 12 (9,83 %) à Donéguébougou, 2 (1,63 %) à Sotuba et 81 (66,39 %) à Bamako. La densité des phlébotomes en novembre était plus élevée, avec 48 spécimens capturés (39,3 %), que celle d’avril, mai et décembre (p ≥ 0,001). A Bamako, les zones 6 et 28 étaient associées aux densités les plus élevées de phlébotomes respectivement 32 (26,22 %) et 23 (18,85 %) (p ≤ 0,005). Les résultats suggèrent que le genre Phlebotomus n’était pas présent à Bamako, et que la densité des vecteurs variait en fonction des zones et des mois. 相似文献
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Paul Bernier Georges Barale Jean-Paul Bourseau Éric Buffetaut Georges Demathieu Christian Gaillard Jean-Claude Gall 《Geobios》1982,15(4):447-467
The first tetrapod Vertebrate track discovered in the late Kimmeridgian lithographic limestones of Cerin (Ain-France), is descrbed as a new ichnospecies, named Chelonichnium cerinense. The characteristics of the track, which is about 7 m long, suggest that it was made by a large Chelonian, but none of the fossil turtles known so far from Cerin is likely to be the author of these footprints. The ground on which the animal walked was apparently very wet, superficially soft, and sloping. Moreover, this track is associated to soft sediment slides, confirming emersion and slope. The depositional environment is interpreted as a platform located behind a «ribbon of islands. This irregular surface was at times emerged and terrestrial tetrapods could then leave tracks on the superficial layer. 相似文献
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《L'Anthropologie》2022,126(5):103074
The contribution of geology and geomorphology to architectural and technological study of the Atlantic coast of France megaliths is important and can be grouped into three main axes: to identify, interpret and dating. Identification refers to the sourcing of the megalithic materiel from 0 to 7 km, sometimes around 10 km, or even exceptionally around 30 km. It is never the entire supply that is affected by such long distances but only a few blocks, some of them are remarkably well staged in the megalithic architecture. Another contribution lies in a fresh look at the management of stone recognized through the modes of acquisition, transformation and use of the raw material. More particularly, the geomorphology associated with technological reading offers tools for recognizing ancient standing stones. In the context of the interpretation of funerary chambers, the two sciences open a large window on the modalities of the internal structuring of monuments. From the entrance to the end of the chamber, the organization and use of the space is documented, sometimes a symbolic coding emerges from the mineral walls. This symbolic coding is based on particular petrography, on surface conditions operating a subdivision of space, on granulometries and homogeneities of differentiated surfaces. The internal organization can also be marked with natural “patterns”, which refer to a completely new aspect of Neolithic thought. Finally, the last axis concerns relative dating, by recognizing forms of postmegalithic fossil erosion, geomorphology makes it possible to identify reused stelae. A very important tool in a current research context where an important episode of reuse of standing stones at the end of the middle Neolithic is anticipated in the construction of dolmens in the south of France. 相似文献
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Peroxidase catalase, IAA-oxidase and polyphenol content of growing barley coleoptile. Effect of kinetin. - Kinetin strongly inhibits root and coleoptile growth of germinating barley in the dark. Treated coleoptiles become senescent before the untreated ones. Soluble proteins content, peroxidase, catalase and IAA-oxidase activity were greatly increased in treated coleoptiles while the level of polyphenols was reduced. These biochemical effects joined with the other property of kinetin to diminish α-amylase synthesis in the endosperm are discussed in relation to growth and in connection with the classic view of a cytokinin retarded senescence. 相似文献
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Two abundant phytoplankters from the St-Lawrence river: Scenedesmus spinosus Chodat 1913 and Pediastrum boryanum (Turp.) Menegh (Chlorophyta, Chlorococca) were sampled, isolated and cultured in monospecific culture. Growth responses were measured after acclimation to different temperatures and after thermal shock treatments.Post-acclimation specific growth rates followed similar patterns with optimal temperatures at about 24°C (S. spinosus) and 26°C (P. boryanum). Final densities were much less influenced by temperature in S. spinosus than in P. boryanum. Post-treatment responses depended on the temperature level maintained after treatment rather than on treatment conditions. No treatment seemed to delay the exponential growth phase. The time needed to reach final densities corresponding to stationary growth phase was not influenced by any thermal treatment. In situ thermal effects at Gentilly nuclear site could be more severe, due to differences in time-temperature history experienced by the algae. 相似文献
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《L'Anthropologie》2018,122(1):33-58
The site of Wujiagou, Hubei Province in China, dated to just over 800,000 years, in sandy deposits and sandy-silt which covers a river terrace of the end of the Early Pleistocene, delivered a rich lithic industry, mainly composed of pebbles tools. This industry has an archaic aspect, consisted by the abundance of pebbles tools, the presence of hand-axes, and the small amount of small tools. The pebble tools include choppers and picks, in addition of band-axes. Small tools are relatively poor and have few simple retouched scrapers. 相似文献
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《Geobios》1987,20(1):123-127
The teleost fish Brychaetus and a dyrosaurid crocodilewere recognized among the aquatic vertebrates recently discovered in the northern area of the Titicaca lake (Bolivia). These fossils allow the presumption of a Paleocene age for the vertebrate bearing formation. The structural interpretation of this chronological data is discussed. 相似文献
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A. Dhainaut 《Cell and tissue research》1973,137(4):481-492
Résumé L'évolution en l'absence d'hormone cérébrale provoque, dans les ovocytes de N. diversicolor, la formation de lamelles annelées cytoplasmiques (L.A.). Le processus débute par l'apparition de lames de réticulum à proximité du noyau (15 jours d'évolution à 15° C). Les lames se rapprochent ensuite du noyau et des pores apparaissent, situés le plus souvent face à ceux de l'enveloppe nucléaire (20ème jour). La différenciation des lames du réticulum en L.A. progresse ensuite depuis les éléments les plus proches du noyau vers les plus externes.Dans le cytoplasme des ovocytes ayant évolué à la température de 20° C, on assiste en outre à la formation d'empilements de citernes ergastoplasmiques. Ces citernes, non situées à proximité du noyau, subissent également une transformation progressive en L.A.L'étude cytochimique effectuée par digestion enzymatique a montré que la pepsine dégrade fortement le matériel dense des lamelles annelées. Ce matériel semble donc renfermer une teneur élevée en protéines auxquelles pourrait se trouver associé du RNA.
Mode of formation of the annulate lamellae of oocytes of Nereis diversicolor developing in the absence of brain hormone
Summary Experimental elimination of brain activity leads to the formation of cytoplasmic annulate lamellae (L.A.) in oocytes of N. diversicolor. This process begins with the appearance of cisternae of endoplasmic reticulum in the vicinity of the nucleus (15 days of development at 15° C). Then, the cisternae move closer to the nucleus and pores appear, often facing the pores of the nuclear envelope (20th day). The differentiation of endoplasmic reticulum into L.A. progresses from the elements closest to the nucleus to the more peripheral ones.In the cytoplasm of oocytes which developed at 20° C, stacks of cisternae of rough endoplasmic reticulum have been observed. These cisternae, which are not localized near the nucleus, also undergo a progressive transformation into annulate lamellae.A cytochemical study, based on enzymatic digestion, shows that pepsin strongly digests the dense material of L.A. This material, therefore, seems to contain a high amount of proteins, perhaps associated with RNA.相似文献
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H. Straus M. Deleanu T. Frits E. Elges Angela Toader 《International journal of biometeorology》1968,12(3):241-249
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