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1.
Summary Newborn male rats were injected with a single dose of dexamethasone on the first day of life. Controls received only the diluent. Two to ten days later the experimental and control animals were sacrificed, and the adrenal medullae were processed for electron microscopy and for histochemical demonstration of catecholamines. Rats that received dexamethasone, as compared to controls showed (1) an earlier appearance of the catecholamine reaction, and (2) a pronounced development of the Golgi complex. These results are further indication that glucocorticoid stimulates the maturation of the chromaffin complex. The Golgi apparatus may play some role in this inductive mechanism.Supported by grants from Consejo Nacional de Investigaciones Científicas y Técnicas Argentina, and Comisión Asesora de Promotión a la Investigatión, Universidad National de Cuyo, Argentina. We are grateful to Teresa H. Fogal Sarmiento for her technical collaborationScientist of Consejo Nacional de Investigaciones Cientificas y Técnicas, Argentina  相似文献   

2.
Summary Seven days of dehydration produce alterations in the Purkinje cells of the toad, Bufo arenarum Hensel. Aldehyde-fuchsin-positive granules appear in the cytoplasm of the cells and at the same time modifications take place in cytoplasmatic and nuclear ribonucleoproteins. These modifications consist of an increase in nucleolar volume and appearance of a nuclear cap, polarized towards the granules.This study was aided by a grant of the Consejo Nacional de Investigaciones Cientificas y Técnicas of Argentina.  相似文献   

3.
Summary The secretory rhythm of neurosecretory cells was studied in supraoptic nuclei of normally drinking rats. Both nuclei were divided in five zones, and in each one, the nuclear and nucleolar volumes of 50 neurons were measured. Parallel observations were made on the Nissl material and neurosecretory granules. Comparative effects of different fixatives showed Carnoy and Zenker to be the best fluids for this type of investigation.Two extreme types of neurosecretory neurons with intermediary stages are observed. Type I neuron has a small nucleus and nucleolus, well developed Nissl bodies and a greater content of neurosecretory material. Type II has larger nucleus and nucleolus, scanty or packed Nissl bodies, and little Gomori positive material. The nuclear and nucleolar volumes differ between the different zones of the supraoptic nucleus and the zone of maximal activity varies in each particular case. To explain this asynchronic behavior a neurosecretory wave of activity moving along the supraoptic nucleus is postulated.Supported by Grants of the Consejo Nacional de Investigaciones Científicas y Técnicas, and the Air Force Office of Scientific Research 314-64.Fellows of the Consejo Nacional de Investigaciones Cientificas y Técnicas.  相似文献   

4.
During 1985–1986, twelve rivers and streams belonging to the Delta Sub-basin (Río de la Plata estuary Basin, Argentina) were sampled for microfauna associated with fifteen species of aquatic macrophytes. A total of 171 species were determined. Ciliates and rotifers were most abundant. Dissimilarities in the colonization of the macrophytes were demonstrated. Water level and current influenced the periphyton community and contributed to the differences observed.Scientific Contribution N 398 of the Instituto de Limnología Dr. Raúl A. Ringuelet. This work was supported by the Comisión de Investigaciones Cientificas de la Provincia de Buenos Aires (Sub. 2109-1449/85).  相似文献   

5.
Phylogenetic trees of transfer RNA specific for phenylalanine, methionine initiator glycine and valine are constructed. Although the exact relationships between taxa cannot be obtained from the mere analysis of the sequences some conclusions can be drawn about the evolution of this molecule.This research was supported by DAAD (Germany) and Comité de Investigaciones de la Universidad de los Andes Bogotá, Columbia. Dedicated to my Son Andres Felipe.  相似文献   

6.
A principal-component scheme was applied to a set of 10 physical, chemical, and biological attributes, measured in 42 samples collected from Los Matadores pond (May 1974–July 1975). The first three components account for 82.1% of the total variance in the data and represent the lotic influence (58.3% of the variance), the seasonal cycle (16.4%), and the degree of maturity (7.4%).The authors are members of the Carrera del Investigador Cientifico y Tecnologico, Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), Argentina.  相似文献   

7.
Summary Candida utilis var. major NRRL-Y-1084 was grown in a defined medium without a phosphorous (P) source. During the exponential phase, cells divided according to a specific growth rate of 0.32 h-1, which is lower than the usual rate for a balanced medium (0.4–0.6 h-1). The relative P content of the biomass decreased from 2.70% to 0.75% over a period of 6 h, including 2 h of cell division arrest. At the end of this period there was another interruption of cell division. After that, multiplication restarted at a considerably lower rate and it deviated slightly from the exponential pattern. The stationary phase began when biomass P content reached 0.4%–0.5%, slowly decreasing afterwards to 0.25–0.20%. Biomass synthesis was less affected than cell division by the relative decrease of endogenous P, the two processes differing partially in their kinetics. Cell lysis started shortly before the stationary phase and affected about 20% of the population by the end of the assay. RNA and P content of the resulting biomass were 2.4% and 0.25% respecitvely, P being mainly incorporated to RNA.The relationship of biomass production to glucose uptake was very low, probably because the marked P deficiency called for an increase in energy consumption for growth and specially for maintenance. Compared with yeasts grown in a balanced medium, 40% increase in glycogen was observed, whereas no mean changes in the content of cell wall carbohydrates (glucan and mannan) and that of true protein were found.Member of the Scientific Researcher's Career of the Consejo Nacional de Investigaciones Cientificas y Técnicas (CONICET). Agrentina  相似文献   

8.
Summary The effect of gonadectomy (at the 10th day of life) and treatment with sexual steroids (during the first month) upon development of alpha-amylase activity in rat parotid gland has been studied.Alpha-amylase specific activity of parotid glands from 20-day-old orchidectomized rats and from 25-day-old ovariectomized animals was significantly higher than that of intact male and female rats of the same age respectively. Spayed males treated with testosterone (10 g/day on the 13th, 15th, and 17th day) and ovariectomized rats treated with oestradiol (2.5 g/day from the 16th to the 22nd day) showed values of enzymic activity similar to those of normal animals.Results indicate that oestradiol and testosterone have an inhibitory effect upon the increase of alpha-amylase activity in parotid gland during a very defined period of development.Career investigators of Consejo Nacional de Investigaciones Cientificas y Técnicas.  相似文献   

9.
Summary Concentrations of up to 10.2 g COD/L were applied to an horizontal anaerobic filter at 40°C, obtaining efficiencies in COD removal of 85%. The contents of the reactor are kept mixed by recycling and at a pH value of 6.9.The addition of alkali to the influent increases the production of biogas reaching a maximum of 250 L of methane per kg of COD removed.Career Investigator of the Consejo Nacional de Investigaciones Cientificas y Técnicas (R. Argentina).Fellow of the Consejo Nacional de Investigaciones Cientificas y Técnicas (R. Argentina).  相似文献   

10.
Cystocarpic and sterile plants of Gigartina skottsbergii produce -carrageenans, while tetrasporophytes produce -carrageenans. No seasonal variation in the carrageenan yields in the three stages was evident. Yields were clearly higher in cystocarpic (34.1–64.7%) and sterile samples (32.3–71.8%) than in tetrasporic plants (10.1–34.0%). Chemical characteristics of the polysaccharides for any stage are the same throughout the year.The authors are Research Members of the Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina.The authors are Research Members of the Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina.  相似文献   

11.
Conclusiones Se efectúa el estudio de 5 observaciones del llamado Micetoma maduromicósico de pulmón en sus aspectos, histopatológico, micológico y clínico.Todas ellas pertenecen a mujeres y configuraron el cuadro de cavidad bronquial empastada, anotando el predominio de su localización en el lóbulo superior izquierdo.Se señala la uniformidad de los caracteres morfológicos que presenta la masa miceliana llamada grano en todos los casos estudiados, en los cuales no fué posible individualizar la existencia de órganos de fructificación que permitiéran una clasificación, cuando más no fuera, genérica del hongo observado.Se critica la aplicación del término Micetoma para éstos casos con igual criterio que el clásico, que supone una enfermedad micótica primitiva, razón por la cual se prefiere hablar de cavidad con contenido micótico o maduromicótico.En el único caso que se logró cultivar al hongo parásito, el estudio micológico del mismo permitió aislar una especie del GéneroAspergillua con caracteres morfológicos sumamente atípicos.
Summary The author presents the study of five observations of the so-called Maduromycosis-mycetoma of the lungs in their clinical, histopathologic and mycologic aspects.The pathologic features in all these cases have been found in bronchial cavities of women, situated in the upper lobe of the lung. A compact mycelial mass, the grain, filled up these cavities.In one of the five cases a fungus was cultivated which was classified as belonging to the GenusAspergillus Michelii, with abnormal and atypical features.Short criticism is presented about the concept Maduromycosis mycetoma of the lung, applied by authors designating this process.
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12.
The activity of Bordetella pertussis extracytoplasmic adenylate cyclase (AC) decreased during decelerating growth phase in a Stainer-Scholte medium. Neither proteolytic activity nor virulence variation (phase variation; antigenic modulation) appears to be responsible for the observed activity fall. The addition of methyl--cyclo-dextrin enhances AC activity and prevents the inhibition of AC activity by fatty acids. Cyclodextrin could entrap inhibitors increasing in this way the AC activity. These results show that the inclusion of cyclodextrin in the culture medium increases the AC activity.D.F. Hozbor and O.M. Yantorno are with the Centro de Investigación y Desarrollo en Fermentaciones Industriales (CINDEFI), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 y 115, (1900) La Plata, Argentina. A. Samo is with the Comisión de Investigaciones Cientificas de la Provincia de Buenos Aires.  相似文献   

13.
Summary Assay methods for chitinase, -glucanase and -glucanase in the presence of the osmotic stabilizers used in fungal protoplast liberation were developed. Chitinase activity with an inorganic osmotic stabilizer system was in the order of NO 3 , Cl>SO 4 2– >PO 4 3– and Na+, K+>Ca2+, Mg2+. Monovalent anion salts with monovalent cations improved chitinase activity, whereas divalent and trivalent anion and cation salts caused appreciable inhibition; phosphate salts induced very serious inhibition. These phenomena suggest that a suitable electrical state is required for optimal chitinase activity. MgSO4, KCl and NH4Cl were equally efficient as stabilizers for protoplast liberation, although they had different effects on chitinase activity. -glucanase was inhibited more by sucrose than by mannitol and sorbitol; -glucanase was relatively stable to both organic and inorganic osmotic stabilizers. As chitin is the major component of the fungal cell wall, chitinase is thought to be more important for protoplast liberation than are -glucanase and -glucanase.
Resumen Se han desarrollado técnicas para la determinación de: quitinasa, -glucanasa y -glucanasa en presencia de estabilizadores osmóticos usados en la liberación de protoplastos fúngicos. La actividad quitinasa con estabilizadores inorgánicos siguió el orden: NO 3 , Cl>SO 4 2– >PO 4 3– Na+, K+>Ca2+, Mg2+. Los aniones monovalentes junto con los cationes monovalentes mejoraron la actividad quitinasa, mientras que tanto aniones como cationes, divalentes y trivalentes causaron una inhibición apreciable. Las sales de fosfato indujeron inhibiciones muy severas. Estos fenómenos sugieren que un estado eléctrico adecuado es necesario para una actividad quitinasa óptima. MgSO4, KCl y NH4Cl fueron igualmente eficientes como estabilizadores para la liberación de protoplastos, aunque tuvieran distintos efectos en la actividad quitinasa. La -glucanasa se inhibió más por sucrosa que por azucares-alcoholes; la -glucanasa se mantuvo relativamente estable frente a estabilizadores osmóticos tanto orgánicos como inorgánicos. Al ser la quitina el componente mayoritario de la pared celular de los hongos, se cree que la quitinasa es más importante que la -glucoanasa y la -glucanasa en lo que concierne a la liberación de protoplastos.

Résumé Des méthodes ont été mises au point pour mesurer les activités -et -glucanase en présence des stabilisateurs osmotiques utilisés pour la production de protoplastes. En présence d'un système minéral de stabilisation osmotique, l'activité chitinase est dans l'ordre NO 3 , Cl>SO 4 2– >PO 4 3– et Na+, K+>Ca2+, Mg2+. Les anions monovalents ainsi que les cations monovalents améliorent l'activité chitinase, tandis que les anions et les cations di- et tri-valents l'inhibent de façon appréciable; les phosphates sont fortement inhibiteurs. Ces phénomènes suggèrent que l'activité chitinase optimale exige un état électrique approprié. MgSO4, KCl et NH4Cl stabilisent de façon identique la formation des protoplastes, bien que leurs effets respectifs sur l'activité chitinase soient différents. L' -chitinase est inhibée par le saccharose davantage que par les sucres-alcools; la -glucanase est relativement stable en présence des stabilisateurs organiques ou minéraux. Comme la chitine est le constituant majeur des parois cellulaires fungiques, on considère que la chitinase est plus importante que la -et l' -glucanase pour la formation des protoplastes.
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14.
Résumé ChezCalotermes flavicollis, la formation des sexués néoténiques est plus facile, ou plus rapide, dans le sexe femelle que dans le sexe mâle.Les sexués femelles montrent un pouvoir inhibiteur à l'égard des individus femelles; les sexués mâles inhibent les mâles de façon moins complète; la stabilisation complète peut être obtenue dans les élevages unisexués, formés uniquement de mâles ou de femelles.La régulation du nombre des néoténiques ne se fait pas de la même façon dans les élevages et dans les élevages . Dans les premiers, 2 néoténiques subsistent, quelquefois 3; dans les seconds ne persiste qu'un seul néoténique , rarement deux.Ces résultats mettent en lumière le rôle différent joué par les mâles et les femelles dans les sociétés de Termites.  相似文献   

15.
Guinea  Emilio 《Plant Ecology》1954,5(1):147-156
Résumé Cette étude vise à faire remarquer la signification, les limites et les caractéristiques du sous-secteur Cantabrique du secteur Ibéro-Atlantique lequel a été proposé pour la première fois dans mon récent travail Geografía Botanica de Santander, Santander, p. 101 (1953).Ce sous-secteur comprend la bande étroite des bords du Nord de la Péninsule Ibérique, limité par la mer Cantabrique et comprenant les provinces de Guipuzcoa, Vizcaya, Santander et la partie Est de la province des Asturies, plus une bande de transition qui, tout le long du versant sud de la Cordillera Cantábrica, suit les limites septentrionales des provinces de Navarre, Alava, Burgos, Palencia, et le coin Nord-Est de Leon.A l'Est, ses limites disparaissent graduellement dans le secteur Pyrénéen, à l'Ouest, il atteint la zone siliceuse des Asturies. Il représente la limite sud de la Province Atlantique.Le climat est humide et tempéré, les hivers sont doux et les étés pluvieux, excepté aux hautes altitudes (au-dessus des 1.000 m). Le relief est très accidenté et montagneux, mais les pics ne dépassent pas les 2.700 m, avec des ruisseaux torrentiels qui rendent possible des innondations comme celles qui ont pris places en automne de 1953. La structure géologique comprend surtout du calcaire du Cretacé avec en plus des grandes masses de dolomites et du calcaire Carbonifère du massif de Picos de Europa. Dans la zone centrale de la Cordillera Cantábrica surgissent quelques rochers du Triassique et d'autres du Jurassique en de petites surfaces. Les terres argileuses et calcaires, très lavées par une pluie intense sont moins répandues (plus nombreuses que les terres siliceuses), avec un pH presque neutre, mais avec des variantes un peu prononcées vers l'acidité (quelques exceptions). Il y a un climax prédominant de forêts du (Quercetum roboris, Fagetum sylvaticae) strictement liées aux pentes des montagnes Cantabres et de Quercetum pyrenaici sur les pentes du sud.Les activités anthropogéniques ont causé la déforestation de la plus grande partie du territoire et ont fait place a un grand développement des landes de l'Uleto-ericetum (Atlantic).Il y a une représentation intéressante du Quercetum ilicis ericetosum sur les bandes de calcaire au-dessous de 800 m. Il est très rare sur les sols siliceux. Les communautés de prairie qui représentent un plagioclimax maintenu par l'homme, éliminent une grande partie de l'Uleto-ericetum que nous avons déjà cité.Il y a des grands champs de maïs et de betteraves à sucre et une extension moindre de céréales et de jardins potagers, et il en resulte une pauvre végétation ségétale et des bords des chemins. Les communautés végétales des plages, falaises, et bords de la mer, celles des mares et des ruisseaux sont très peu développées.On cultive avec intensité le Pinus radiata et l'Eucalyptus globulus. Il reste à exploiter en grand, l'agriculture, les pâturages, et la sylviculture.

Received for publication 15.I.1954.  相似文献   

16.
Individuals and societies embody illnesses in different ways, in part determined by the way a person knows and lives his or her diagnosis and prognosis. Based on research in Northern Italy, on the experiences and meanings of cancer and on the practice of nondisclosure of the diagnosis, we find nondisclosure reflects a world divided - life/death, good/bad, mind/body — with the unwanted converted to other. The strong association of cancer with death, suffering, and hopelessness in much of Italy, coupled with the tremendous power attributed to naming and sentencing makes nondisclosure a major mechanism for keeping the condemned in this social world, and keeping death, decay, and suffering in the other. It is the social reality that is dominant here, such that informing a patient of cancer can be tantamount to social death.
Résumé Les individus et les sociétés incorporent la maladie de façon différente, déterminée en partie de comment une personne connait et vit son diagnostic et prognostic. A partir de la recherche des experiences des significations du cancer et de la pratique de ne pas dire la diagnostic au Nord de l'Italie, on a remarqué que l'habitude de ne rien dire reflète un monde séparé entre la vie et la mort, entre le bon et le mal, entre l'esprit et le corps, de sorte que ce qui West pas voulu soit transfomé en l'autre. L'association forte du cancer à la mort, à la souffrance, au désespérance en toute l'Italie, unie au grand pouvoir donne au fait de dénommer et de donner une sentence, rend ne pas dire un méchanisme important pour garder le condamnd dans ce monde social et pour garder la mort, la décadence et la souffrance dans l'autre. C'est la réalité sociale qui est ici dominante, tel que le fait d'informer un patient de cancer soit comme une mort sociale.
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17.
Resumen En este trabajo se estudia en la Parte I todo el material procedente de especímenes clínicos.En primer lugar se estudian las cepas aisladas de Micosis Superficiales o Dermatomicosis.En segundo lugar, los hongos levuriformes del género Candida procedentes de materiales clínicos varios.En tercer lugar los agentes de Micosis Profundas, y finalmente los hongos del aire de Caracas que tienen interes alergológico.Los resultados de todo aparecen en los cuadros sinópticos adjuntos.
Summary In this part of our work we deal with fungi of clinical interest.Firstly, we study specimens isolated from dermatomycoses.Secondly, yeast-like fungi of the genusCandida of clinical origin.Thirdly, fungi producing systemic mycoses and lastly, air-borne fungi of allergic interest from Caracas and its surroundings.

Résumé Dans la première partie de ce travail, on étudie tout le matériel d'intérêt médical.En premier lieu, les souches isolées de matériel clinique de Mycoses Superficielles ou Dermatomycoses.En deuxième lieu, les champignons lévuriformes du genre Candida provenant de matériaux cliniques variés.En troisième lieu, les Agents de Mycoses Profondes et, finalement, les champignons contenus dans l'air de Caracas intéressant la Mycologie Allergique.


(Trabajo de la Sección de Micología del Instituto Nacional de Higiene)

Trabajo presentado al IV Congreso Venezolano de Tisiología y Neumonología, Valencia, Diciembre 1959.

Jefe de Sección Micología. — Instituto Nacional de Higiene. Jefe de Sección Micología.-Hospital Universitario. Profesor de la Catedra de Micología.-Escuela de Bioanálisis Fac. de Medicina U C V.

Directora de la Micoteca Nacional.-Seccion de Micología, Instituto Nacional de Higiene.  相似文献   

18.
Summary Five categories of granulated cells were distinguished by their ultrastructural features, and quantitative analyses were made of the pars distalis cells in normal and castrated lizards. The gonadotropin-producing cell was identified on the basis of its uniform distribution in the gland as well as from cytological changes resulting from castration. The secretory granules of the gonadotropic cell vary in size (100–500 m) and density, and lipid bodies are commonly present. Following castration, the endoplasmic reticulum proliferates, forming many small, rough-surfaced, dilated cisternae which do not coalesce greatly as in other vertebrate species. Degranulation is accompanied by hypertrophy and hyperplasia of the mitochondria and by the appearance in the cytoplasm of conspicuous clusters of microfilaments. The designated gonadotropic cell was the only class of secretory cell showing consistent changes following three weeks of castration.In addition to the uniformly distributed gonadotrope cell, two secretory cells occur mainly in the rostral half of the gland, and two in the caudal half. Tentative identification of the cell types is discussed in the light of available information on the localization of the hormones in the pars distalis of this species.Grateful recognition is given to the Electron Microscope Laboratory of the University of California, Berkeley, for use of their facilities, and to Emily Reid for her assistance with the illustrations.Member of Consejo Nacional de Investigaciones Cientificas y Técnicas.  相似文献   

19.
Sami Lakkis 《Hydrobiologia》1973,43(1-2):235-252
2275 samples have been collected with the Continuous Plankton Recorder of Hardy at a standard depth of 10 meteres in the English Channel and the Bay of Biscay between 1958–1965. Biological as well as statistical analyses have been carried out to provide data on annual fluctuations of 34 species of copepods and phytoplankton. Methods of analysis of variance and the correlation coefficient analysis were used for this purpose. The results are presented in the form of triangular matrices showing the annual fluctuations of species in the different areas considered and the relationship between different species in each area. These methods allowed us to define separate groups of species that could be called annual communities.

Extrait d'une thèse de Doctorat en Oceanographie biologique, soutenue à la faculté des Sciences de Paris le 19 décembre 1967. Ce travail a été subventionné par the Office of Naval Research, Department of the United States Navy en vertu du contrat No 62558-3612.

Extrait d'une thèse de Doctorat en Oceanographie biologique, soutenue à la faculté des Sciences de Paris le 19 décembre 1967. Ce travail a été subventionné par the Office of Naval Research, Department of the United States Navy en vertu du contrat No 62558-3612.  相似文献   

20.
Summary In a previous paper, we have used the density of the population as a sort of measure of the unknown size n of the isolates in Dahlberg's model, and shown an inverse relation between the coefficient of inbreeding and the density of the arrondissements. In the present paper, as the considered communes are smaller territorial subdivisions than arrondissements, we used, instead of the density, the population size of the communes. The results are even more eloquent as before: the inbreeding coefficients are large when the observed population size is small; the relative importance of second cousin marriages (233) versus cousin marriages (222) is greater in the latest period considered. The basic data have been collected for each commune in Belgium by Centre National de Radiobiologie et de Génétique.  相似文献   

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