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1.
Resume 14 activités enzymatiques (3 deshydrogénases et 11 hydrolases) ont été recherchées systématiquement sur les électrophorégrammes en gel d'agar des extraits de 2 souches de Aspergillus fischeri et de 14 souches de A. fumigatus (8 isolées de lésions humaines ou animales intitulées souches pathogènes, et 6 souches d'origine saprophytique). La composition enzymatique de A. fumigatus est apparue très polymorphe et sans rapport avec l'origine des souches.D'autre part, l'analyse immunoélectrophorétique de ces extraits antigéniques, par des sérums de lapins hyperimmuns et des sérums de malades atteints d'aspergillose, a montré que l'activité chymotrypsique de type II, supportée par l'arc C, est caractérisée de manière plus fréquente et plus intense lorsque les antigènes provenant de souches pathogènes sont opposés à des sérums de malade.De plus, si cette activité chymotrypsique est révélée avec la même fréquence par une souche saprophyte et une souche pathogène, le nombre de précipitines mises en évidence est apparu significativement plus élevé avec cette dernière.Les antigènes utilisés pour le diagnostic de précipitation en gel devraient donc être, de préférence, extraits de souches pathogènes et leur qualité évaluée par des sérums de malades atteints d'aspergillose.  相似文献   

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Resumé L'ultrastructure de la cuticule et des éléments qui lui sont associés, a été étudiée chez trois espèces de Cestodes. Les résultats ont été interprétés en vue: 1. de donner un support morphologique aux fonctions d'absorption dont la cuticule est le siège, 2. d'établir une analogie histologique avec un épithélium intestinal. Chez deux espèces de Cestodes (Pseudophyllides) des éléments particuliers, les organites rhabdomorphes, ont été découverts dans la cuticule. Différentes voies morphologiquement possibles pour l'absorption des substances exogènes sont discutées.
Summary Ultrastructure of cuticle and associated structures has been studied in three species of Cestodes. Results have been interpreted in the two following ways: 1. To give a morphological basis to functions of absorption which occur at this level, 2. to furnish an histological analogy with an intestinal epithelium. In two species of Cestodes (Pseudophyllideans), particular elements, the so-called rhabdomorphous organites, have been found in the cuticle. Different morphologically possible pathways for absorption of exogenous substances are discussed.


Travail ayant bénéficié de l'appui du Fond National Suisse pour la Recherche Scientifique.  相似文献   

3.
Do the blind cave salamander Proteus and its epigean relative Necturus use the chemical sense in searching for prey? Proteus shows a significant, and Necturus only a weak, preference for water which passes living prey before entering a choice chamber. Prey which was frozen before the test also gave the same result in both species. However, with this immobilized prey the time for a decision in the test was much longer. The results of ten series of tests demonstrate the importance of chemoreception for prey detection in Proteus. The weaker reactions in Necturus can be explained probably by the different biotope.Six other series of tests have been conducted to show that our results are not influenced by stimuli relating to mechanoreception, thigmotaxis and rheotropism.  相似文献   

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In Lymnea stagnalis (F 1 generation) carbaryl weakly disturbs the growth of the shell with 2 ppm, strongly with 4 ppm (lethal concentration for the young snails).The shell growth inhibition by lindane is correlated with the concentration (1 & 2 ppm). The degree of intoxication of parents is very important. The two insecticides play a complex part in the mineralization of the shell. The effects of lindane on growth and mineralization of the shell have a reversible character.  相似文献   

6.
In Lymnea stagnalis (F1 generation) carbaryl induces a decrease of fecundity for a given age, correlated with the concentration; this decrease is due to a delay in growth. With ppm of lindane a diminution of fecundity is observed which is more prominent with 2 ppm. The number of egg capsules and the number of eggs per capsule are decreased. In F1 intoxicated snails, the degree of the intoxication of their parents seems to play an important part. When the intoxication is stopped, the reversible character is demonstrated.All these chronic intoxication experiments show that lindane is more injurious than carbaryl for the freshwater snails studied.  相似文献   

7.
Protein synthesis and accumulation in growing sunflower (Helianthus annuus L.cv.Airelle) seeds are studied. The salt soluble fraction, globulin, is the main soluble protein component. The earlier stages of seed development (10 days after flowering) are characterized by high Mr polypeptides (74, 58 and 44 kDa). Later stages mainly show nature globulin polypeptides. Thus, protein synthesis in seed occurs at a specific period of seed development which follows a period of fast cell divisions (0–14 days after flowering). Protein bodies are isolated and their protein composition analyzed. Globulin subunits are the main polypeptides of protein bodies soluble fraction. Mature globulin is only stored in protein bodies.   相似文献   

8.
Summary A histological, histochemical and ultrastrucutral study of the pars intercerebralis (PI) has been made in Locusta migratoria. The acellular neural lamella is made up of an elastic tissue and collagen fibrils. The cells of the perilemma contain numerous lysosome structures and lipid granules.Three different types of neurosecretory cells (NSC A, B and C) have been distinguished in the PI associated with giant neurons.The cells termed A and B seem not to have an activity cycle during the two last larval instars. At the moment of sexual maturity the NSC A show an important accumulation of neurosecretory material and their number increases at the expense of the NSC B. The NSC A, which are characterized by a highly developped endoplasmic reticulum, contain numerous secretory granules which appear to be individualized in the Golgi complex in three different ways. The NSC B, with a reduced endoplasmic reticulum and an almost quiescent Golgi complex, contain abundant lysosome structures and more seldom some neurosecretory granules. In fact, the study of the fine structure shows different intermediate types, linking in a continuous way typical A cells and typical B cells. NSC A and NSC B might correspond to two opposed stages of secretory activity of one single cell type: the A cell representing the activity stage and the B cell the quiescent stage.NSC C show an accumulation of their neurosecretory products in relation to metamorphosis and sexual maturity. Ultrastructural evidence confirms their neurosecretory activity.A mode of regulating neurosecretion in NSC A and B by internal catabolism of the secretion and formation of lysosome like structures is discussed in the present paper.The giant neurons, which are surrounded by a glial envelope (trophospongium), contain several dense granules originated from Golgi complex.  相似文献   

9.
Résumé L'étude ultrastructurale des spermatogonies et des spermatocytes a été envisagée chez Lithobius forficatus L. (Myriapode Chilopode). Les spermatogonies présentent un noyau à chromatine dispersée dont le nucléole est condensé. Leur cytoplasme renferme des ribosomes, libres ou associés en polysomes; les mitochondries et les dictyosomes sont peu abondants.Au cours de la croissance spermatocytaire, le noyau et le cytoplasme augmentent considérablement de volume. La dispersion de la chromatine est plus importante et le nucléole présente de nombreuses figures de bourgeonnement. Les ribosomes, les mitochondries, les dictyosomes et le reticulum endoplasmique sont très abondants. De nouvelles formations sont observables: 1) des amas de saccules réticulaires concentriques, délimitant une zone cytoplasmique; 2) des empilements lamellaires ayant leur origine soit dans le reticulum banal, soit dans les amas concentriques.L'activité synthétique se manifeste lors de la croissance spermatocytaire par: 1) d'abondants échanges nucléo-cytoplasmiques; 2) une augmentation du nombre de mitochondries et des ribosomes; 3) une intense activité golgienne. Elle est vraisemblablement en rapport avec le gigantisme spermatocytaire observé chez les Myriapodes Chilopodes.
Ultrastructural study of spermatogonia and spermatocyte growth of Lithobius forficatus L. (Myriapoda, Chilopoda)
Summary The ultrastructure of spermatogonia and spermatocytes of Lithobius was studied. The spermatogonia show a nucleus with dispersed chromatin and a compact nucleolus. Their cytoplasm contains free ribosomes and polysomes; mitochondria and dictyosomes are not abundant.During spermatocyte growth, nucleus and cytoplasm increase markedly in volume. The dispersion of the chromatin is more pronounced; the nucleolus shows frequent budding. Ribosomes, mitochondria, dictyosomes and endoplasmic reticulum are very numerous. New structures are (1) accumulations of concentric reticular saccules with a cytoplasmic center, (2) piles of narrow cisternae originating from the regular endoplasmic reticulum or from concentric saccules.The synthetic activity during spermatocyte growth manifests itself by (1) numerous signs of nucleo-cytoplasmic exchanges, (2) an increase in the number of mitochondria and ribosomes, (3) a high activity of the Golgi apparatus. This is probably related to the gigantism of spermatocytes in Chilopoda.
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10.
In this report, B9 treatment had no effect on the growing of rosette biennialScrophularia vernalis L.; it inhibited or slowed stem elongation. Applications of GA3 to B9 treated plants produced a significant increase of stem elongation, in relation to GA3 treated plants. Plants treated with only GA3 failed to flower; otherwise, the flowering of vernalized plants was not altered by GA3. Thus, B9 effect on flowering was tested by using GA3. B9 by itself induced flowering, it increased inflorescence formation in vernalized plants without altering stem growth pattern in the most of cases. The induction or the stimulation of flowering brought about by B9 was not reversed by GA3; we may thus hypothesize that flowering by B9 oannot be traced back to gibberellin biosynthesis.  相似文献   

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Summary A method is described which permits the measurement of the tetrathionate reductase activity of bacterial extracts. In anaerobic cultures the reductase is an inducible enzyme. In aerobic cultures its formation is completely repressed by oxygen. In a suspension of resting cells atmospheric oxygen inhibits reversibly the activity of the reductase.   相似文献   

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The absorption of32P-phosphate (KH2PO4-0.1 mM) was studied with discs ofPelargonium zonale leaves, in relation to the age of the leaf, to the ageing process and in relation to the influence of GA3 and BAP. The results show that: i) the speed of absorption reaches a maximum which is characteristic of the adult phase (stage); ii) the “ageing” (washing during 24 h) induces a general increase in the absorption velocity which is dependent on the temperature of the ageing medium (optimum at 26 °C). On the other hand, ageing appears to be a process able to increase the physiological differences which are present before “ageing”. This phenomenon also appears in the case of the influence of phytohormones; iii) if BAP exercises a dose-dependent inhibitory action, in contrast, GA3 acts by increasing the velocity of the absorption which appears to be a process independent of the hormone concentration. These results underline a phytohormonal specificity. All these results are discussed in relation to hormone-directed transport, cell permeability and leaf senescence.  相似文献   

15.
The abdominal vertebrae of the adult carp retain a bulk of cartilage at the basement of the haemapophyses. This cartilage has two opposite directions of differentiation. There is an enchondral ossification of the hypertrophic calcified cartilage in its distal area whereas its proximal area is calcifying without previous hypertrophy. The calcification of this proximal area (hyaline calcified cartilage) is permanent and shows typical rings and waves of Liesegang. The calcification of the cartilage of the hemapophyses is of a globular type. The hyaline calcified cartilage is not a metaplastic bone. Other studies, specially with electron microscope, will allow us to understand the innermost process of the different stages of calcification in the cartilage of the carp.  相似文献   

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V. Delucchi 《BioControl》1961,6(2):97-101
Summary The author examines in his report some aspects of the relations existing between the ecologists of the C.I.L.B. working teams and the taxonomists which collaborate with the identification centre, and between these taxonomists and the identification centre itself. The collaboration between taxonomists and ecologists must certainly be encouraged by the C.I.L.B., especially with regard to those biological control projects such as the Olive fly and the San Jose Scale, where behavioural caracters of the parasitic species may be determinant for their identification. Emphasis is given to the importance of the behavioural caracters in taxonomy and examples of this are reported. The collaboration between taxonomists and the identification centre of the C.I.L.B. would be favoured through the following: 1. The establishment of a card file at the C.I.L.B. head-quarters on the entomophagous insect species and their known hosts for a future publication of a synoptic catalog for the palaearctic region; 2. The institution of fellowships for taxonomists to study Museum collections; 3. The establishment of a homotype collection at the C.I.L.B. headquarters, which will constitute, with the file card system, a solid base for the future development of taxonomic work; 4. The reservation of a day for discussions about nomenclature questions at every C.I.L.B. meeting of taxonomists. The author recommends to address reprints concerning the taxonomy and systematic of entomophagous species to the C.I.L.B. headquaters (Entomologisches Institut der E.T.H., Universit?tstrasse 2, Zürich 6, Switzerland) for the establishment of an extensive reference collection to be used for publication of the bibliography on this subject.   相似文献   

19.
Resumé La formation de la membrane exuviale chez la nymphe de Tenebrio molitor est étudiée à l'aide de techniques histochimiques et au microscope électronique.Dès les premières heures de la vie nymphale, l'épiderme sécrète, en même temps que les lamelles d'endocuticule post-exuviale, un matériel de stabilisation de nature lipoprotéique. Ce matériel se dépose sur la sous-cuticule et sur une partie de la dernière lamelle d'endocuticule formée. Après le décollement de l'ancienne cuticule, le matériel de stabilisation se condense sur la trame chitineuse de la sous-cuticule pour former une membrane exuviale résistante au liquide de mue.La réaction de la sous-cuticule et de la membrane exuviale aux différents tests histochimiques, en particulier à l'APS, est discutée.
Summary The formation of the ecdysial membrane during the pupal life of Tenebrio molitor is studied by histochemical and electron microscopical techniques.During the first hours of the pupal life, the epidermis secretes a lipoprotein complex which contains sterols. The term stabilizing material is applied to this secretion. The stabilizing material is added to the subcuticle and to a part of the last endocuticular lamella. After epidermis retraction, this material is condensed on the chitin framework of the subcuticle to form an ecdysial membrane resistant to the moulting fluid.The reaction of the subcuticle and ecdysial membrane to different histochemical tests (especially to the PAS-test), is discussed.


Nous tenons à exprimer notre reconnaissance au Professeur A. G. Richards pour la lecture du manuscrit et ses intéressantes suggestions, et au Dr M. Gabe pour ses précieux renseignements concernant l'étude histochimique. Notre gratitude va également àu Professeur Ch. Noirot, notre directeur de recherche, pour ses encouragements constants et son aide efficace.  相似文献   

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