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A. Aizawa  C. Vago 《BioControl》1959,4(3):249-252
Zusammenfassung Es wird auf die M?glichkeit hingewiesen, plastische Kunststoffe für die Kultur von Insektengeweben zu benutzen. Die Entwicklung der Zellen auf Polyvinylchlorid-Folien ist ebenso gut wie auf Glas; es lassen sich auch fixierte und gef?rbte Pr?parate herstellen, und die Kunststoff-Folien lassen sich mit Kanadabalsam zusammenkleben und aufbewahren. Die Vorteile von Kunststoff-Gef?ssen werden hervorgehoben.   相似文献   

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The new analysis of the Middle Paleolithic industry from the cave Vindija (Croatia), showed a necessity of revision of the previous obtained data especially considering the use and origin of the raw materials (Kurtanjek and Marci, 1990). The results presented in this study pointed out some new aspects of interpretation. First, the significance of quartz in the Middle Paleolithic was underestimated. At the same time it is obvious that the major change in the use of the raw material was at the beginning of the Upper Paleolithic and of the Epigravettian, especially in the use of chert. The second change is registered in the use of chert between Middle and Upper Paleolithic: the chalky nodules of chert are more frequent in the Upper Paleolithic then the river pebbles used in the production of Middle Paleolithic artefacts. Still, the origin of this new raw material is at the moment unknown.  相似文献   

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The collect of the fossiliferous nodules starts in 1979 in the Saint-Louis opencast mine at Montceau-les-Mines, France. A team of amateur paleontologists excavates more than 100,000 nodules containing very well-preserved fauna and flora from the Late Carboniferous (Stephanian).  相似文献   

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A series of plankton net samples (200 μm mesh width) was collected in the New Caledonian lagoon. From observations by scanning electron microscopy, six larval forms of chaetosphaera are described for the first time. In spite of criticism concerning the use of morphology of setae, the features of transitional larval setae are the main criterion for distinguishing these forms. Nine criteria are used: (1) arrangement of fascicles with regard to the body—pen as a fan and transverse or tightened and parallel to the body; (2) arrangement of fascicles with regard to the dorsal side—entirely or partly sheltered; (3) number of morphological types of setae; (4) number of setae in the fascicles; (5) general morphology—capillary and straight or curved and spiny or as blade-shaped sword; (6) cross section of the setae; (7) arrangement of spines; (8) morphology of distal end; (9) colour. It appears likely that chaetosphaera larvae belong to species of the genera Scolelepis, Dispio or Australospio as defined by Blake & Kudenov and not to Laonice cirrata, as previously thought. In order to display this difference, the larvae of Laonice sp. are also illustrated. Diagnosis of chaetosphaera may be provisionally based on the following features: prostomium pointed; larvae curled to the ventral side; dorsal side without chromatophores; notopodial setal bundles open as a fan on each side and sheltering, at least in part, the dorsal side. Une série de prélèvements au filet à plancton (200 μm de vide de maille) est réalisée dans le lagon de Nouméa, Nouvelle Calédonie. Six formes de larves chetospheres d'Annélides Polychètes sont décrites par observation au microscope électronique à balayage. Les caractères diffèrentiels reposent principalernent sur la morphologie des soies provisoires. Neuf criteres sont utilisés: (1) disposition des faisceaux par rapport au corps—en éventail et transversale ou fermée et parallele au corps; (2) disposition des faisceaux sur la face dorsale—cette dernière peut être entièrement ou partiellement protégée; (3) nombre de types morphologiques de soies; (4) nombre de soies dans un faisceau; (5) morphologie générale—capillaire, droite, avec ou sans épines ou bien courbée et épineuse ou bien aplatie en forme de lame de sabre; (6) section transversale de la soie; (7) disposition des épines; (8) morphologie de la partie distale; (9) coloration. II resort de cette étude qu'il est maintenant nécessaire de rapporter les larves du type chéAtosphère—au moins certaines d'entre elles—à des espèces appartenant aux genres Scolelepis, Dispio ou Australospio tels qu'ils sont définis par Blake & Kudenov. Correlativement la correspondance entre les chétosphères et les larves de Laonice cirrata ne semble pas confirmée. La reconnaissance des larves chétosphères peut être provisoirement basée sur les caractères suivants: prostomium pointu, corps enroulé autour de la face ventrale, tégument dorsal sans chromatophores, faisceaux de soies notopodiales ouverts en éventail et protégeant au moins en partie la face dorsale.  相似文献   

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Variability is one of the most debated topics in lithic technology studies. For the Middle Pleistocene period, this debate has specifically focused on the significance of large cutting tools such as handaxes and cleavers. This paper presents the stone tool assemblage from Covacha de los Zarpazos site, included in the Galería complex at Sierra de Atapuerca (Burgos, Spain). We analyse the management of lithic raw materials, the reduction sequences identified, and the morphological variation in the shape of large cutting tools. The results show that raw materials play an important role in the final variability of tool shape, although they do not represent any real constraint. However, what determines the main variability of a whole lithic assemblage is the occupation strategy and the specific activities carried out in a given site.  相似文献   

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In every species other than mammals xanthine oxidoreductase behaves as a dehydrogenase, never as an oxidase. In three mammalian species, the enzyme acts intracellularly as a dehydrogenase, but its class-specific ambivalence allows its extracellular conversion into an oxidase.

Résumé

En dehors de la classe des Mammifères, l'oxydoréductase de la xanthine ne se comporte jamais comme une oxydase. Chez les Mammifères, une ambivalence de la molécule permet l'expression d'une activité déshydrogénasique (NAD) dans la cellule, et d'une activité oxydasique en dehors de la cellule.  相似文献   


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Over recent years, many discoveries have renewed our knowledge about the oldest stone industries and also about the behaviour and lifestyle of the hominids that made them, not only in East Africa, but also in the Near East, in Trans Caucasia and in southern Europe. If the first tools making hominids appear in East Africa as early as 2.55 million years ago, they are present in the Levant a little over 2 million years ago, as early as 1.81 million years ago at the gates of Europe in Trans-Caucasia, and a little over 1.4 million years ago on the Mediterranean coasts of Europe.  相似文献   

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The optical rotatory dispersion of copolymers of O-carbobenzoxy-L -tyrosine and benzyl L (or D )-glutamate as well as benzyl L -aspartate, dissolved in nonpolar solvent, has been studied. Moffitt's equation permits the determination of b0 coefficients whose variation, with varying composition in amino acid residues, suggests that the molecules of poly-O-carbobenzoxy-L -tyrosine have a helical structure similar to that of poly-(benzyl L -glutamate). Results obtained from infrared spectroscopy and x-ray diffraction show that the copolymers possess a helical conformation in the solid state, even when they are very rich in carbobenzoxy-L -tyrosine residues. The value of the b0, coefficient for poly-O-carbobenzoxy-L -tyrosine may be explained by a regular stacking of the chromophore groups around the helical backbone. The ordering of the molecules of this polymer in a purely helical structure seems favored by the insertion of a small number of foreign residues in the polypeptide chain.  相似文献   

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F. Giran 《BioControl》1966,11(4):405-407
Summary The virus of Densonucleosis ofGalleria mellonella (Lepidoptera) is not virulent for mice and rabbits by inoculation and by feeding. Newly born mice are not contamined by intracerebral inoculation. These data are important for comparison of this virus with some Arthropod born viruses and for biological control.   相似文献   

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C. Vago  S. Chastang 《BioControl》1962,7(2):175-179
Summary The comparative study of cultures of the tissues of the ovary sheath of the female gonad and of the hemocytes of Lepidopterous by means of varying proportions of insect serum and calf serum, has revealed that the serum of mamalians can to a great extent take the place of insect serum. Nevertheless the incorporation of a small amount of insect serum is beneficial to the culture. The principle which is described makes it possible, in particular, to cultivate the tissues of very small insects.   相似文献   

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The thick Quaternary deposits of the Caune de l’Arago (Pyrénées-Orientales, France) are dated to between 690 000 and 90 000 years old. At least fifteen different archeostratigraphical units have been identified within these deposits, each corresponding to distinct prehistoric occupations. Numerous stone tools made from several different rock types, have been discovered in each unit. The tools present specific characteristics concerning the choice of raw materials, the typology, and the technology used to produce them. Morpho-technological study of the different components of the assemblage contributes to a better understanding of the debitage methods used for their production. Each raw material is considered individually in order to ascertain its origin in the environment, its typological role and the technology applied during its exploitation. Defining production systems leads to the characterisation of the assemblages from each unit. When compared, they reveal common elements, as well as differences, suggesting evolutionary trends. Some observations are also made concerning the extent to which changing uses of the site may have influenced the general morphology of each assemblage, therefore taking into account exterior factors. Analysis of this rich stone tool assemblage helps to situate the Caune de l’Arago industry within the larger evolutionary context of the Lower Paleolithic in Mediterranean Europe.  相似文献   

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