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1.
Résumé Les populations levuriennes de deux chais de Bourgogne sont étudiées sur deux années d'un point de vue taxonomique et biologique. 122 souches se rapportant à 26 espèces, ont été isolées à partir de la voûte et du sol de la cave, sur les madriers supportant les tonneaux, dans la cuve, sur le pressoir et sur les tonneaux. En dehors d'un certain nombre d'espèces classiques dans ce type d'habitat, telles que Saccharomyces cerevisiae, Pichia membranaefaciens, Hansenula anomala et Kloeckera apiculata, nous avons pu mettre en évidence notamment: Debaryomyces hansenii, Torulopsis Candida, Saccharomyces italicus, ainsi qu'un certain nombre d'espèces appartenant aux genres Pichia, Candida et Trichosporon. La répartition qualitative et quantitative des espèces est également étudiée.
The yeast populations of two burgundy cellars were studied during two years from a taxonomical and biological point of view. 122 strains distributed among 26 species have been isolated from the vault and ground of the cellar, on the planks supporting the barrels, in the tank, on the winepress and on the barrels. Apart from a number of standard species in this type of habitat such Saccharomy cescerevisiae, Pichia membranaefaciens, Hansenula anomala, Kloeckera apiculata we have encountered the more rare Debaryomyces hansenii, Torulopsis Candida, Saccharomyces italicus as also species of the genus Pichia, Candida, and Trichosporon.
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2.
Zusammenfassung Untersucht wurden die Speicheldrüsen der Ratte bei verschiedenen Kostarten und im Megaphenschlaf, des Siebenschläfers (Myoxus myoxus) und des Igels (Erinaceus europaeus) im Winterschlaf und Wachzustand.Die Speicheldrüsen der Ratte zeigen in Abhängigkeit von der Kostart verschiedene histologische Bilder.Bei Trockenkost leitet der allgemeine Wasserverlust des Gewebes ein Inaktivitätsstadium ein, das durch einen Schwund der Sekretgranula und eine Abnahme der Zytoplasmabasophilie gekennzeichnet ist. Der letzteren entspricht ein Schwund des Ergastoplasmas. Langdauernde Milchkost bewirkt eine Schwellung der Zelleiber, der Kerne, Nukleolen und Mitochondrien.Im Hungerzustand waren in den geschrumpften Endstückzellen Austritte RNS- und DNS-haltigen Materials aus den Zellkernen, sowie ein Schwund der diffus verteilten RNS und des Ergastoplasmas zu beobachten.Die Speicheldrüsen von Winterschläfern weisen eine deutliche Schrumpfung der Endstücke auf, welche von einem RNS- (Nukleolen-) und DNS-Schwund in den Kernen sowie von einem Schwund der diffusen zytoplasmatischen RNS und des Ergastoplasmas begleitet ist. Gleichzeitig fällt die Millon-Reaktion schwächer als bei wachen Tieren aus. Während des Winterschlafes ist in den Endstücken der Speicheldrüsen von Myoxus myoxus, Erinaceus europaeus und den Zellen der Ausführgänge von Myoxus myoxus auffallend viel Glykogen vorhanden. Gleichzeitig kommt es in den Endstückzellen zu einer Verschleimung. Die basale Streifung der Ausführgangsepithelien ist während des Winterschlafs dicht, beim wachen Tier aufgelockert und von Vakuolen durchsetzt. Die Anfärbbarkeit von Stoffen im lumennahen Pol der Ausführgangsepithelien mit Perjodsäure-Leukofuchsin und Aldehydfuchsin legt die Annahme nahe, daß hier ein aktiver sekretorischer Vorgang vorliegt. In diesem Zusammenhang wird die Frage der Rückresorption diskutiert.Bei der weißen Ratte kommt es im Megaphenschlaf zu einer Verschleimung der Endstückzellen, die von einer starken Glykogenablagerung und Zunahme der mit Perjodsäure-Leukofuchsin und Aldehydfuchsin färbbaren Stoffe in den Ausführgangsepithelien begleitet ist. In den Acini treten RNS- und DNS-haltige Substanzen in großer Zahl aus dem Zellkern aus.Das histologische Verhalten der Speicheldrüsen des Megaphentieres (Ratte) entspricht nicht dem Strukturbild der Drüsen des Winterschläfers (Siebenschläfer).Herrn Prof. K. Niessing danke ich für die Überlassung eines Arbeitsplatzes, Herrn Dr. A. Oksche für Unterstützung bei der histochemischen Methodik, Fräulein E. Hauberg für die Anfertigung der Photographien.Stipendiat der Alexander von Humboldt-Stiftung, Bonn.  相似文献   

3.
Summary During the period between apolysis and ecdysis, the vesicular glands show many important transformations which affect not only the cuticular ductules, but all the cells. The cytoplasm of the glandular cells undergoes a partial autolysis, whereas other parts of the cells present a high secretory activity. Immediately after the apolysis the cellular reservoir empties and disappears almost completely; soon after, refills with secretion. The most interesting transformations concern each ciliary cell, always associated with a glandular cell. In the first phase of the moulting cycle, the dendrite of the ciliary cell grows a ciliumlike extension (= distal region of the dendrite), which penetrates into the corresponding ductule; the new intima of this ductule is laid around the cilium. At the same time, the proximal region of the dendrite forms a circular fold around the base of the cilium and begins to secrete a material which will form the end apparatus. This latter is finished during the second phase of the cycle. The third phase is characterized by the degeneration of the distal region of the dendrite and the circular fold. Thus, the end apparatus is not a secretion of the ductule-carrying cell, but of the ciliary cell. At the end of the moulting period, just before ecdysis, the vesicular gland again takes the structure characteristic of the intermoult: the reservoir of the glandular cell is very large; the cuticular apparatus is almost formed; the dendrite of the ciliary cells shows, at its apex, a short cilium (= ciliary region s. str. + short distal region) surrounded by microvilli, free in the secretion of the reservoir.  相似文献   

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The distribution of lysine-derived alkaloids in the genus Lycopodium (s.l.) supports the separation of the following taxa, Huperzia (= Urostachys), Lycopodiella s.l. (= Lepidotis, excl. L. volubile and L. deuterodensum) from Lycopodium s. str. Within the latter, the Fastigiatum group and the Complanata section (= Diphasiastrum) can be distinguished. The results obtained are in good agreement with the classification proposed by Wilce.  相似文献   

6.
R. Mieusset 《Andrologie》1997,7(4):419-426
Spermatozoa morphology is one of the qualitative characteristics of spermatogenesis. However, because of both the variations in the definition of normal morphology and the existence of different kinds of sperm abnormalities as well as the use of various techniques of morphology assessment, such a parameter is poorly used in usual laboratory work. Morphological sperm anomalies can be from testicular or post-testicular origines, while the latter is still unproved. The causes of such anomalies are either from genetic origines, but in these cases any spermatozoa demonstrate this anomaly, or due to an endogenous factor with varicocele the most usually quoted but unproved pathology, But exogenous factors, either chemical such as drugs and pesticides or physical such as heat, are also responsible for morphological sperm anomalies. Analysis of sperm morphology is indicative of both the testicular health status (in cases of occupational exposure to chemical or physical toxics) and the fertility potential since morphology is correlated to sperm motility and involved in fertilization through the acrosome reaction.  相似文献   

7.
Over the last fivty years, the risk factors for infertility have increased substantially, particularly those due to the environment. Spermatogenesis and spermatozoa can be affected by physical (ionizing radiation microwaves, heat, cryopreservation) or chemical agents (antimitotics drugs, antibiotics, tranquillizers, insecticides, pesticides, industrial solvants, some heavy metals, alcohol, cannabis etc.). Some natural factors, as stress or paternal age (ageing or very youthful age relatively to about thirty) also seems to affect spermatogenesis and, particularly, the age can be joined with the previous ones. On the whole, these factors are able to decrease the male fertility through some changes about the concentration, the motility or the morphology of spermatozoa and so it is possible to describe populations subject to the risk. Moreover, these spermatogenetic changes can lead abnormalities in progeny. For instance, some antimitotic drugs as cyclophosphamide, when administrated to the male rat, lead malformations or functional anomalies as behavioral troubles. The industrial solvents lead a decrease of the birth weight and the cannabis leads an increase of the ante-or post-natal death. Moreover, the change of the paternal spermatogenesis caused by cannabis can be found again in the male progeny. The problem is similar with the lead, the benzodiazepines and the alcohol. Concerning the physical factors, some authors have shown that the children born from radiation exposed fathers presented an increase of the probability of leukemia. In animal, the postimplantation loss is increased when the father is irradiated or subjected to heat before mating. Finally, the paternal ageing is responsible for new dominant autosomic mutations. Moreover, in animal and man, paternal ageing and, in man, very youthful age, also seems responsible for a gradual lowering in the level of progency cerebral functions. On the whole, these data should lead to an preventive attitude which would be more effective before about thirty years of age than after this period.  相似文献   

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9.
Semen analysis, as defined by World Health Organisation (WHO), is a fundamental step in the work-up of infertile couples. Spermatozoa morphology has been recognised as the best predictive factor in natural fertility, and in intrauterine insemination and classicalin vitro fertilisation. Ultrastructural spermatozoa abnormalities are the only sperm alterations likely to influence the outcome of ICSI. However, these abnormalities cannot be detected by conventional microscopy (¥100 or ¥200–400). Bartoov et al. (2002) developed a real-time spermatozoa observation system using a ¥6600 magnification called MSOME (Magnification Motile Sperm Morphology Examination). Spermatozoa abnormalities detected with this technique are vacuoles localised on spermatozoa heads with variable number, size and site (nucleus or acrosome). Spermatozoa evaluation using MSOME could be performed to predict the probability of fertilisation by these spermatozoa either spontaneously or after assisted reproductive technology.  相似文献   

10.
11.
Les larves et les adultes de la bruche du haricot se nourrissent de deux types d'aliments différents, mais proches en ce qui concerne la composition en hydrates de carbone: les larves consomment des graines de Phaseolus vulgaris et P. coccineus, les adultes s'alimentent principalement avec le pollen de diverses plantes.L'activité des larves et des adultes a été étudiée sur 22 substrats, en vue de préciser les caractéristiques de leur équipement osidasique. Les recherches ont montré que les larves et les adultes possèdent un équipement très important en - et -glucosidases, en - et -galactosidases, ainsi que des activités très importantes sur certains polysaccharides, notamment l'amidon et la pectine, mais l'activité est faible sur les hémicelluloses étudiées, notamment la xylane, l'arabinogalactane et la glucomannane. Les activités sur la carboxyméthylcellulose et la cellulose, ainsi que l'inuline, sont nulles.La corrélation étroite entre la composition en hydrates de carbone de la nourriture et les activités glycosidasiques du canal alimentaire chez les larves et les adultes permet une utilisation optimale des ressources trophiques en hydrates de carbone. Le parallélisme frappant entre le système glycosidasique des larves et celui des adultes a pour explication la ressemblance entre la composition en carbohydrates du pollen et celle de l'endosperme de haricot.
Summary Adults and larvae of Acanthoscelides obtectus eat two different types of food, similar in carbohydrate composition: larvae eat seeds of Phaseolus vulgaris and P. coccineus, adults eat principally pollen of various plants. The authors have studied the digestive activity of larvae and adults on 22 different sugars, in order to investigate activity of their glycosidase enzymes. Larvae and adults have a very important complement of - and -glucosidases, - and -galactosidases, and very high activity against certain polysaccharides, notably starch and pectin. The activity is weak on the hemicelluloses tested, notably on xylan, arabinogalactan and glucomannan. No activity is found on carboxymethylcellulose, cellulose and inuline.The close correlation between the carbohydrate composition of the food and the glycosidase activity of the alimentary canal in both larvae and adults enables optimal utilization of carbohydrate resources. The striking parallel between the glycosidase systems of adults and larvae is explained by the similar carbohydrate composition of pollen and bean endosperm.
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12.
Zusammenfassung Für 10 Zellarten der normalen Maus, für 5 fetale Zellarten der Ratte (20. Tag der Gravidität) und für 3 Aszites-Tumoren wurde das Auftreten von tageszeitlichen Schwankungen des H-3-Index und des Mitose-Index untersucht. Die Tötung der Tiere erfolgte jeweils 40 min nach Injektion von H-3-Thymidin. Von den Organen wurden Autoradiogramme hergestellt.Bei einer Reihe von Zellarten des erwachsenen Tieres wurden neben den bekannten tageszeitlichen Schwankungen des Mitose-Index auch Schwankungen des H-3-Index gefunden.Bei allen Zellarten mit Schwankungen des Mitose-Index wurden ohne Ausnahme auch solche des H-3-Index beobachtet. Demgegenüber zeigten bei anderen Zellarten beide Indices keine Schwankungen.Bei den fetalen Zellarten und den Ascites-Tumoren wurden weder tageszeitliche Schwankungen des H-3-Index noch des Mitose-Index gefunden.Die tageszeitlichen Schwankungen des H-3-Index werden als — bei einer bestimmten Tageszeit auftretende — partielle Synchronisationen der Zellen gedeutet. Aus den gemessenen Kurven des H-3-Index wird der tageszeitliche Verlauf der Eintritts-Rate der Zellen in die S-Phase berechnet (Signalkurve).Es wird diskutiert, ob die tageszeitlichen Schwankungen des Mitose-Index als ein selbständiger Prozeß oder als eine notwendige Folge der H-3-Index-Schwankungen zu deuten sind.
Summary Diurnal fluctuations of the H-3-index and the mitotic index were investigated in 10 different cell types of normal mice, in 5 fetal cell types (rats, 20th day of pregnancy) and in 3 ascites tumors. The animals were sacrified 40 minutes after injection of H-3-thymidine. Autoradiographs were prepared from various organs.Diurnal fluctuations of the H-3-index were observed in a number of cell types of the adult animal, aside from the diurnal fluctuations of the mitotic index known already. These H-3-index fluctuations were found without exception in all cell types in which diurnal fluctuations of the mitotic index were observed. In other tissues diurnal fluctuations could not be demonstrated with both indices. Diurnal fluctuations of the H-3- and the mitotic index were also not present in the fetal cells and in the ascites tumours.The diurnal fluctuations of the H-3-index are regarded as partial synchronisations of cells which occur at a certain time of day. The daily time course of the rate of entry of cells into S-phase is calculated from the H-3-index curves measured (signal curve).It is discussed whether the diurnal fluctuations of the mitotic index are to be regarded as an autonomous process or as a necessary consequence of the H-3-index fluctuations.


Wir möchten Herrn Dr. W. Erb für Mithilfe bei der Auswertung der Versuche, der Fa. Dr. Madaus & Co., Köln-Merheim, für die Überlassung der Versuchstiere herzlich danken. Weiterhin danken wir Herrn Dr. L. Révész, Karolinska Institut, Stockholm, für die Überlassung des tetraploiden Ehrlich-Ascites-Tumors. Die Arbeit wurde durch Mittel der Gesellschaft zur Bekämpfung der Krebskrankheiten in Nordrhein-Westfalen und des Bundesministeriums für Wissenschaftliche Forschung unterstützt.  相似文献   

13.
La nervation des élytres d’Acrididae de la région ouest paléarctique a été étudiée au moyen de 2 méthodes de morphométrie de manière à faire ressortir les caractères adaptatifs relatifs à la stridulation et les marqueurs de phylogénie. Huit Points de Repère (PR) situés dans la région proximale des élytres, incluant le champ médian, ont été considérés pour l’analyse de morphométrie géométrique. L’importance relative des champs a été appréhendée par ACP. Il apparaît que le dimorphisme sexuel des PR caractérise les espèces à stridulation de forte intensité chez le mâle (Gomphocerinae et Stethophyma grossum). Les mâles présentent par rapport aux femelles un élargissement des champs sous-costaux antérieur et postérieur, et du champ radial, lié à un déplacement distal de la bifurcation entre les radiales antérieure et postérieure, ce qui entraîne un élargissement de la surface de résonance. L’élargissement du champ cubital antérieur est une déformation propre à la tribu des Locustini et n’a pas de valeur adaptative apparente.  相似文献   

14.
Most of the numerous techniques used to assess sperm viability only have research applications, while only two classical tests, i.e. eosin-Y and hypo-osmotic swelling test (HOST), are currently used in routine sperm analysis to determine the percentage of viable sperm. A viability rate below 50% of living sperm defines necrozoospermia, a condition whose clinical significance is fairly difficult to assess as the mechanisms of sperm cell death are still poorly understood. However, even when a precise cause for necrozoospermia cannot be identified, abnormal viability requires further andrological investigations with particular emphasis on clinical and laboratory signs of chronic infection of the male reproductive tract. Intracytoplasmic sperm injection (ICSI) can yield very good pregnancy rates, even in couples with the most severe forms of male infertility. However, when no motile sperm are available after sperm preparation, the outcome of ICSI is seriously impaired, probably because of a high risk of injecting dead sperm. In these patients, sperm viability could therefore be assessed by the hypo-osmotic swelling test in order to select only viable sperm for ICSI. However, the long incubation time of sperm in the hypo-osmotic solution, as recommended in the classical HOST procedure, has been shown to be detrimental to the spermatozoa. A single sperm test able to assess the viability of each individual spermatozoon within microdroplets covered by mineral oil therefore seems to be preferable. This selection procedure is less suitable in the case of immotile frozen-thawed sperm, as viability does not appear to be reliably predicted by HOST in cryopreserved sperm. Examination of sperm viability now also evaluates programmed cell death or apoptosis, as apoptotic alterations can be detected in spermatozoa by several techniques. The percentage of apoptotic sperm is correlated with deficient sperm parameters and poor outcome of assisted reproductive techniques. More effective selection procedures are therefore needed in order to identify spermatozoa not only with intact membranes but also with an intact genome to be used for ICSI.  相似文献   

15.
Diese Arbeit bringt Ergebnisse phytozönologisch-ökologischer Forschungen der Waldgesellschaften NO-Böhmens, des am rechten Elbeufer zwischen Hradec Králové-Městec Králové-Ji?ín und Ho?ice gelegenen Gebietes. Folgende Syntaxa wurden untersucht: dasGalio-Carpinetum Oberd. 1957 mit fünf Subassoziationen (colchicetosum, typicum, primuletosum veris, luzuletosum albidae, molinietosum arundinaceae), dasPotentillo albae-Quercetum Libb. 1933 (Ausbildungsform vonFestuca heterophylla), dasLuzulo albidae-Quercetum (Hilitzer 1932)Pass. 1953 emend. R. etZ. Neuh. 1967 und dasMolinio ar.-Quercetum R. etZ. Neuh. 1967 mit zwei Varianten (typische Var., Var. vonSphagnum). Eine besondere Aufmerksamkeit wurde den Standortsverhältnissen der unterschiedenen Syntaxa (bes. den physikalischen und chemischen Bodeneigenschaften) gewidmet.  相似文献   

16.
Horst Senger 《Planta》1970,90(3):243-266
Summary Using synchronous cultures, the change in the potential photosynthetic capacity and the behavior of the photosynthetic quotient were investigated during the life cycle of Scenedesmus obliquus, strain D 3. Scenedesmus obliquus was synchronized under a light-dark regime of 14:10 hours. The quality of synchrony was demonstrated by complete synchronization, homogeneity, exponential growth, shortest possible life cycle and non-susceptibility of the life cycle to the synchronizing procedure. Furthermore, the synchronous culture was characterized by determination of cell number, dry weight, packed cell volume, chlorophylls a and b and the carotenoids during the life cycle.The potential photosynthetic capacity (as O2 evolution) was measured manometrically and polarographically in white light. This capacity increased from the beginning of the light period until the 8th hour and then declined until the 16th hour, that is until just before release of daughter cell. The percentage difference between the maximum and the minimum of the photosynthetic capacity was the same in the light saturating and light limiting region of photosynthesis. — The photosynthetic quotient was measured by means of Warburg's indirect method. It proved to be constant throughout the life cycle under light saturating and light limiting conditions. The ratio of O2 evolved to CO2 consumed was just below unity.The results were compared with those of other authors and their significance was discussed. It was concluded that the change in the photosynthetic capacity is inherent in the normal life cycle of green algae and is not a result of the synchronizing light-dark regime.

Erster Teil einer Habilitationsschrift der Naturwissenschaftlichen Fakultät der Philipps-Universität Marburg. Auszüge dieser Arbeit wurden auf dem International Congress of Photosynthesis Research in Freudenstadt im Juni 1968 vorgetragen.  相似文献   

17.
Résumé L'étude ultrastructurale de l'appareil dioptrique des photorécepteurs des Collemboles adultes a permis de reconsidérer la structure des formations oculaires à ommatidies aggrégées. Quatre types de cornéules ont été reconnus, dont les plus remarquables sont ceux à mamelons cornéens. Les cellules cristalliniennes au nombre de quatre assurent alternativement une double fonction au cours de chaque cycle de la mue. Sur les faces distales, les cellules élaborent le matériel cuticulaire de la cornéule; vers l'intérieur elles sécrètent le cristallin. Les cellules de Semper réalisent ainsi une fonction cornéagène et une fonction cristallogène. La répartition spatiale des organites intracellulaires en couches concentriques est une caractéristique des Collemboles. Chaque cellule cristallinienne envoie vers la membrane basale un processus tubulaire contenant des granules denses de nombreux microtubules et du glycogène en faible quantité. Les cônes cristallins présentent une grande diversité de forme de structure et de composition chimique. Suivant les groupes le cristallin peut être une formation intracellulaire ou extracellulaire, simple ou quadripartite. La présence de petits cristallins satellites associés à un cristallin unique reste inexpliquée mais caractérise une espèce troglobie Tomocerus problematicus. Deux cellules dites cornéagènes à cytoplasme toujours pauvre en organites intracytoplasmiques, avec ou sans pigment, complètent l'appareil dioptrique des ommas des Collemboles.
Photoreceptors of Collembola, an ultrastructural studyI. The Dioptric Apparatus
Summary Ultrastructural features of the dioptric apparatus of photoreceptors of adult Collembola described by the author has enabled the author to compare the structure of ocular formations with aggregated ommatidia. Four different types of corneulae have been determined, the most remarkable of which are those showing corneal nipples. The four crystalline cells have alternately different functions during each molting cycle. On their distal surfaces, the cells elaborate cuticular material of the corneula; proximally, they secrete a crystalline cone. The Semper cells thus have both corneogenous and crystallogenous functions. The typically concentric spatial distribution of intracellular organelles in these cells is a characteristic feature for Collembola. Each crystalline cell sends towards the basal membrane a tubular process containing granules, numerous microtubules, and a small amount of glycogen. The shape, the structure, and the chemical composition of the crystalline cones are highly variable. In Collembola, the crystalline formation can either be intracellular or extracellular, and it can be simple or quadripartite. No explanation has yet been advanced for the existence of small crystalline satellites which appear to be associated with the single large crystalline cones; this association is characteristic for the troglobian species Tomocerus problematicus. The dioptric apparatus of Collembolan ommatidia is completed by the presence of two corneogenous cells, the cytoplasm of which contains few organelles and in some cases pigments.
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So far in France, sperm donor anonymity, which was a fundamental principle and has been twice confirmed in the law in 1994 and 2004, is debated nowadays. In this context, the Cecos wanted to know the donors opinion on anonymity. In 2006, 193 semen donors recruited in 14 Cecos answered anonymously a questionnaire: 73% were in agreement with the principle of anonymity and less than 30% agreed that the future law should change to allow the children to know the donor identity. In case of anonymity disclosure, 60% would give up their sperm donation. The same proportion of donors would accept that non identifying information on them could be given on request to the parents and the child.  相似文献   

20.
Leaves of Holarrhena febrifuga from East Africa contain 1·5% of alkaloids, mostly of the amino-3α ceto-20 pregnane-5α type. Six alkaloids have been isolated: funtumine (I), holamine (II), dimethyl- and monomethyl-funtumine (Ia) and (Ib), dimethyl- and monomethylholamine (IIa) and (IIb); these methyl derivatives have been isolated for the first time from natural source. Pregnane-3,20-dione has been isolated from the same leaves.  相似文献   

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