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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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Conventional semen analysis (sperm count) is limited to examination of spermatozoa at a magnification of x1,000, which may be insufficient in rare situations. Electron microscopy sperm examination allows high-power (x 100,000) analysis of sperm organelles and quantification of abnormalities of the constituents involved in sperm mobility and fertility potential. Electron microscopy sperm morphology examination is rarely indicated and is reserved to: 1) severe monomorphic and stable teratospermia (globozoospermia = spermatozoa with a round head and no acrosome, pinheads = decapitated spermatozoa), 2) partial (asthenospermia) or total (akinetospermia) alteration of sperm mobility and/or quality of sperm movement. All of these anomalies are associated with primary infertility. Globozoospermia and pinheads can be detected by light microscopy. Electron microscopy sperm morphology examination precisely identifies and quantifies sperm abnormalities. Pathological phenotypes have a heterogeneous expression. The organelles of spermatozoa other than those primarily involved in the pathological phenotype may also present alterations. Globozoospermia is generally characterized by the absence of elongation of the nucleus, and absence of the acrosome and the post-acrosomal region. The implantation fossa and basal plate are generally missing in decapitated spermatozoa. Asthenospermia may be an indication for electron microscopy sperm examination when it is not associated with necrospermia. Sperm with fibrous sheath dysplasia (FSD) generally present a short flagella and very low overall mobility, less than 5%. The various phenotypes are characterized by abnormal arrangements of the constituents of the fibrous sheath and 20% of patients also present respiratory tract disease. In primary ciliary dyskinesia (PCD), spermatozoa are often immobile and present a normal morphology on light microscopy. Apart from the complete form with absent axoneme, incomplete forms are also observed with absence of the dynein arms, peripheral doublets, microtubules. These phenotypes have a low prevalence in the population of infertile men. A familial incidence, parental consanguinity, and a high incidence in certain geographical regions are frequently reported, suggesting the existence of one or several genetic mechanisms. Despite the limited state of knowledge at the present time, couples must be informed about the possible transmission of the phenotype to their descendants. All men with these phenotypes are spontaneously infertile. The only alternative fertilization technique is intracytoplasmic sperm injection (ICSI). According to the literature and our own experience, the results of ICSI with sperm presenting these phenotypes are poorer than those of ICSI in general. Electron microscopy is not only a diagnostic tool in severe male infertility, but also a prognostic indicator of the success of management by ICSI, which must be evaluated for each case.  相似文献   

4.
From an experience of radio-immunotherapy of non Hodgkin lymphomas from March 2002 to December 2008 (near 7 years), corresponding to 160 treatments, an analysis of indications has been done: clinical research trials, authorized indications from AMM or medically justified. Some elements which could be problematic are pointed: coordination between the regional Haematology departments and our Nuclear Medicine department, radio labelling and radioprotection.  相似文献   

5.
From a survey of 30 species and varieties of ladybugs the presence of alkaloids appears to be correlated with the existence of aposematic colour and not with being carnivorous or phytophagous. The alkaloids described until now all belong to the Coccinellini and are closely related, but other types of bases have been detected in some genera. The observed distributions are in agreement with the modern taxonomy of the family.Ladybug alkaloids constitute an effective defence against ants, Myrmica rubra, and quails, Coturnix coturnix, but all the beetles containing alkaloids do not possess the same degree of protection. Individual quail react differently towards moderately protected species.The bioassay used for the first isolation of coccinelin is described. The repulsive activities of aqueous solutions of coccinellin and convergin towards ants have been compared.  相似文献   

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This paper follows the first part: Legrand-Blain &alii, 1983,Geobios, no 16, fasc. 3.The brachiopods here described from the «Culm are: Schizophoria cf. resupinata, Rhipidomella michelini, Actinoconchus aff. paradoxus, Lamellosathyris gr. lamellosa, Cleiothyridina (Leiothycridina) nov. sp. gr. okensis, Podtsheremia (s.l.) convenarum nov. sp., Neospirifer gr. derjawini, Anthracospirifer (?) sp., Brachythyrina (Anthracothyrina) perextensa nov. subgen., nov. sp., «Spirifer lujkiensis, Zaissania nov. sp., Kitakamithyris or Torynifer (?) sp., Martinia minima. From shales associated with the Ardengost limestones, slightly different faunas are: Podtsheremia (s.l.) convenarum (?), Anthracospirifer (?) sp., Brachythyrina (Anthracothyrina) bressoni nov. subgen., nov. sp., Phricodothyris mosquensis, Martinia buckmani.The brachiopods from Ardengost limestones andassociated shales, well dated, are of upper Serpukhovian age. The «Culm ones might be heterochroneous, with Serpukhovian and (?) Bashkirian elements. The paleoecology of the brachiopods from limestones and associated shales indicates moderate and low energy environments. The «Culm brachiopods display both resedimentation and delicate preservation features. There is evidence of rather close palaeobiogeographic relationships with the northern Sahara: during the late Serpukhovian, a «Sahara-Pyrénées region could be distinguished, at the western part of the vast Tethysian province.  相似文献   

8.
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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Phylogenetic relationships among fungi belonging to the family of Ustilaginaceae (genera Microbotryum, Sphacelotheca, Ustilago, Sporisorium) are inferred from a parsimony analysis using the ITS sequences of nuclear ribosomal genes. The introduction in the phylogeny of sequences from species of Suillus, Puccinia and Taphrina as outgroup shows the polyphyletism of this family. These results support the division of this taxon into two groups: Ustilaginaceae s. str. formed only by the pathogens of Poaceae, and Microbotryaceae constituted by the pathogens of Dicotyledons. Furthermore, we proposed to extend the host plant spectrum of Ustilaginaceae s. str. to all the Monocotyledons. Several discriminating characteristics are listed to support this distinction.  相似文献   

11.
Galperin  H. 《Human genetics》1967,4(1):6-12
Human Genetics - Ce travail comporte des analyses de la variance de la longueur et de l'indice brachial des chromosomes 1, 2 et 3, de cellules ayant subi une endoréduplication.  相似文献   

12.
Willy Humbert 《Zoomorphology》1974,78(1-2):93-109
Résumé Le mésentéron des Collemboles est riche en inclusions minérales appelées sphérites. L'étude de leur genèse nous montre qu'ils se forment dans les citernes du réticulum endoplasmique. Leur croissance et leur évolution se poursuivent dans les mêmes citernes par apport de matériel divers. Les sphérites sont formés de nucléi opaques aux électrons entourés de couches concentriques alternativement claires et sombres. Les critaux âgés sont souvent associés à des enroulements membranaires. Le rôle physiologique est discuté. Ces concrétions apparaissant dès l'éclosion, peuvent s'éliminer de differentes manières: par extrusion apocrine, par dégénérescence cellulaire et surtout par le renouvellement périodique de l'épithélium intestinal qui se fait à chaque mue. Ces sphérites peuvent représenter une voie d'excrétion par accumulation et semblent jouer le rôle des tubes de Malpighi qui font défaut chez les Collemboles.
Summary The mesenteron of Collembola is rich in mineral inclusions called spherites. The study of their genesis shows us that they are produced in the cisternae of the endoplasmic reticulum. Their growing and evolution occur in the same cisternae by adduction of diverse material. The spherites are composed of dark nuclei surrounded by alternatively clear and dark concentric strata. The aged cristals are often connected with membraneous windings. The physiological role is discussed. These concretions which appear already after hatching, cancel out by apocrine extrusion, by cellular degeneration and especially by periodic renovation of the intestinal epithelium which occurs at each moulting. These spherites could reflect a process of excretion by accumulation and seem to have the same part as the Malpighian tubules which lack in Collembola.
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13.
J. Costentin 《PSN》2010,8(4):182-186
Caffeine, the main alkaloid in coffee, corresponds to the 1-3-7 trimethylxanthine. Its concentration is lower in tea and chocolate, where it is associated with theophylline, 1-3 dimethylxanthine, in tea and with theobromine, 3-7 dimethylxanthine, in chocolate. Paraxanthine, 1-7dimethylxanthine, for its part, is produced by the hepatic metabolism of caffeine operated by a cytochrome of 1A2 type. The effects of these methylxanthines on awaking, anxiety, neuroprotection in Alzheimer’s and Parkinson’s diseases, mood, schizophrenia and nociception are briefly considered. This review is concluded by indicating that these effects of methylxanthines may be modified by various associated substances, such as polyphenols displaying antioxydant properties.  相似文献   

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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   

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The holarctic subfamily Melitaeinae of Nymphalid butterflies (old genus Melitaea Hbn.) has been split into various genera by morphological systematics, but this division has been debated. This work presents the results of a preliminary survey of European taxa using two types of molecular criteria: analysis of enzyme variation by electrophoresis (19 loci) and sequencing of a mtDNA fragment (ND1 gene). The information provided by both kinds of markers are largely congruent. The division of the subfamily into two monophyletic lines corresponding to the genera Euphyryas s. 1. and Melitaea s. l. is validated. The subsequent division of the former genus into two units, Eurodryas and Hypodryas is also confirmed by molecular criteria. Inside rhe old genus Melitaea, a monophyletic assemblage, corresponding to the ‘Mellicta group’ is disclosed, but the phylogeny of the other species of the group is confused. Uniting them in a ‘Didymaeformia group’ or in a genus Melitaea s. str. risks rhe generation of a paraphyletic assemblage. It remains to be determined whether or not these results are due to insufficient resolution, or whether they reflecr a real evolutionary pattern  相似文献   

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Résumé Les auteurs étudient l'influence des stations d'épuration sur la population de levures dans les eaux usées d'origine urbaine. Quantitativement, le nombre de microorganismes diminue de 90% lors du traitement. 49 espèces ont été identifiées. Les témoins de pollution d'origine humaine ont été plus particulièrement recherchés. Les auteurs indiquent les modes de détection du Candida albicans.The authors have studied the influence of sewage treatment plants over the yeast population in the waste waters coming from towns. Quantitatively, the number of microorganisms shows a 90% decrease in the process of the treatment. 49 different species have been identified. Evidence of pollution coming from human being has been particularly looked for. The authors point out the different ways of detecting the Candida albicans.  相似文献   

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The Glénan Archipelago was investigated, from the surface to a depth of 60 m, byScuba diving. Four distinct communities (“peuplements”) have been determined that fit into the system of zonation defined by the Genoa Symposium (1957). The results are compared with observations made in the English Channel (Cabioch 1968) and in the Atlantic Ocean (Glemarec 1971). Since illumination depends upon the angle of the rocky face, photophilic species exhibit a maximum range when the rock surfaces are horizontal. The sublittoral zone is dominated by laminarians. They form two distinct communities with the animal and vegetal species they overshadow. The upper community is characterized byLaminaria digitata (Linné)Lamouroux (horizontal rocky face from 0 to 6 m; vertical rocky face from +0.5 to ?3 m). The lower cummunity, characterized byL. hyperborea (Gunner)Foslie has a greater vertical extension (horizontal: ?6 m to ?26 m; vertical: ?3 to ?30 m). The circalittoral zone is colonized by several animal species growing in a ramified manner: the upper community is characterized by Axinellidae (?30 m), the lower byDendrophyllia cornigera (Lamarck) (?55 to ?60 m). Upright algae disappear somewhere between ?40 and ?47 m.  相似文献   

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