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101.
Jean J. Pasteels 《Cell and tissue research》1969,102(4):594-600
Résumé Dans toutes les cellules mucipares de la branchie de Mytilus edulis L., quelques grains de secretion montrent une activité phosphatasique acide, décelée par la méthode cytochimique de Gomori appliquée au microscope électronique. A la proximité de ces grains se trouvent des dictyosomes golgiens où une activité phosphatasique se décèle dans les parties latérales des cisternes et dans les vésicules qui en émanent. Au moment de l'excrétion, tous les grains de sécrétion confluent et la phosphatase acide active est incluse dans l'amas de mucus expulsé dans la cavité palléale. Le rôle digestif de ces amas — et non purement mécanique — peut ainsi être considéré comme hautement probable. De telles manifestations enzymatiques sont totalement absentes dans le tapis muqueux ainsi que dans les cellules qui le constituent.
Excretion of acidic phosphatase by the goblet-cells of the gill of Mytilus edulis L.An electron microscopic study
Summary Acidic phosphatase activity detected by the Gomori method applied to E.M., has been found in a few secretion granules of each goblet cell of the gill of Mytilus edulis L. In the close proximity of those granules golgian dictyosomes always occur, with acidic phosphatase activity in the lateral parts of the cisternae and in the vesicles arising from the latter. When the mucus is extruded, active and non active secretion granules are mixed and thus, acidic phosphatase activity is regularly found in the mucous tufts extruded into the palleal cavity. Therefore the digestive role — and not merely mechanic — of the mucous tufts may be considered as highly probable. Conversely, the secretion granules from which arises the continuous mucous cover of the epithelium and this cover also, are entirely devoid of any acidic phosphatase activity.相似文献
102.
Platelet aggregation has been related to blood coagulation studies in patients on nicoumalone, a coumarin anticoagulant. Aggregation studies were performed by means of Chandler''s tube and the adenosine diphosphate (A.D.P.)-induced optical density method. Platelet aggregation in Chandler''s tube has been shown to be quite different from A.D.P. aggregation and to be dependent on the “intrinsic” (blood) clotting system. When the intrinsic system was depressed by coumarin anticoagulant, aggregation was delayed in Chandler''s tube, but patients with a predominantly “extrinsic” (tissue) system defect gave normal results even when their prothrombin time was excessively prolonged. In contrast there was an increased response to A.D.P. in the anticoagulated patients.The study emphasizes the different mechanisms of platelet aggregation, which we have referred to as coagulation-induced and A.D.P.-induced aggregation. It also shows the limitations of routine control of oral anticoagulants by prothrombin time alone, as the coagulation-induced platelet aggregation appears to be quantitatively related to the overall level of clotting factors in the intrinsic system and independent of the extrinsic system. 相似文献
103.
Reductive Pentose Cycle and Formate Assimilation in Rhodopseudomonas palustris 总被引:2,自引:0,他引:2
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Rhodopseudomonas palustris assimilated formate autotrophically as carbon dioxide and hydrogen arising from the activity of the formic hydrogenlyase system. Kinetic analyses of cell suspensions pulse-labeled with (14)C-formate or (14)C-bicarbonate showed similar distributions of incorporated radioactivity. In both cases phosphate esters were the first assimilation products. Ribulose diphosphate carboxylase, phosphoribose isomerase, and phosphoribulokinase, characteristic enzymes of the reductive pentose cycle, were present in extracts of cells grown on formate. 相似文献
104.
Jean Hubert 《Cell and tissue research》1970,107(2):265-283
Résumé Les gonocytes primaires sont relativement pauvres en polysomes et l'ergastoplasme granulaire est très réduit. Le reticulum endoplasmique de type lisse se développe au cours du développement embryonnaire. L'appareil de Golgi est bien représenté et localisé au niveau de la calotte juxtanucléaire mitochondriale. Les liposomes cytoplasmiques sont très nombreux.Cette étude précise la structure du nucléole «annulaire» et de la «masse paranucléolaire» observés en microscopic photonique. Des modifications nucléolaires sont constatées au cours du développement embryonnaire. Certains aspects ultrastructuraux sont vraisemblablement en rapport avec le déplacement autonome des gonocytes. La signification physiologique du nucléole «annulaire» et de la «masse paranucléolaire» est envisagée.
Ultrastructural study on the primordial germ cells during embryonic development of Lacerta vivipara Jacquin
Summary The primordial germ cells of Lacerta vivipara have relatively few free polysomes and little ergastoplasm. Smooth endoplasmic reticulum increases during embryonic development. The Golgi apparatus is well developed and lies close to the mitochondrial juxtanuclear cap. This study shows the ultrastructure of the ring-shaped nucleoli and the masse paranucléolaire. Modifications in nucleolar structure are observed during embryonic development. Some ultrastructural features are probably related to the ameboid movement of the primordial germ cells. The physiological meaning of the ring-shaped nucleoli and the masse paranucléolaire is considered.
Avec la collaboration technique de Mme. M. Hubert. 相似文献
105.
Differential Tolerance of Streptomycetes to Sodium Chloride as a Taxonomic Aid 总被引:2,自引:1,他引:1
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A survey was made of the NaCl tolerance of approximately 1,300 Streptomyces strains belonging to 313 species. The growth medium of the organisms was supplemented with a graded series of NaCl concentrations (4, 7, 10, and 13%). Only 1.8% of the species could not tolerate 4% NaCl; 26.9% could grow at a maximum of 4%; 49.7% could tolerate a maximum of 7%; 18.8% could grow at a maximum of 10%; and only 2.8% could tolerate 13% NaCl. In evaluating the relationships of NaCl tolerance to various taxonomic features, higher tolerance was statistically associated with the "yellow" and possibly the "white"-spored streptomycetes, whereas the "red"-spored series tended to have lesser tolerance. Higher tolerance was also indicated for spiny-spored species, as a group, than for smooth-spored forms. Likewise, nonproducers of melanin, collectively, were more NaCl tolerant than melanin-producing species. Uniformity of test responses between strains of species studied suggested the usefulness of NaCl tolerance as a taxonomic criterion. 相似文献
106.
107.
108.
A 20-year-old woman had a cyst of the proximal part of the common bile duct and a cyst of the left hepatic duct; these lesions were diagnosed preoperatively by intravenous cholangiography and successfully operated upon. At the time of writing, she has been followed up for one year.Congenital defects in the biliary system are rare and, in a review of the literature, only two cases were found similar to this one. It is generally accepted that these lesions are congenital, but the exact pathogenesis is unknown.Alonso-Lej, Rever and Pessagno2 reviewed the literature in 1959 and found 403 authentic congenital cysts of the hepatic ducts. The most common congenital defect is a single choledochal cyst of the lower end of the common bile duct. Pain, jaundice and tumour are the main symptoms.Until the advent of intravenous cholangiography, these lesions were seldom recognized preoperatively. Means of operative repair as well as complications and prognosis are reviewed. 相似文献
109.
Coxsackie A9 virus was identified by the authors during the fall of 1965 in Montreal in six children with fever and exanthem. Three of the six children were siblings. The exanthem was centrally distributed as described by Lerner et al. and consisted of discrete maculopapules 3 to 4 mm. in diameter. The viral agent was recovered and identified in tissue culture in five cases, while in the sixth Coxsackie type-A lesions were produced in suckling mice. Serological confirmation was obtained in two patients from whom sera were available. In contrast, no exanthem was observed in three older patients with a diagnosis of aseptic meningitis associated with Coxsackie A9 virus. In only one of 16 patients with Coxsackie B virus infection was an exanthem observed during the same period.The true incidence of Coxsackie A9-associated exanthems is difficult to determine because of the benign nature of the disease. 相似文献
110.