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《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1999,322(5):429-439
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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XVIème Congres de la Societe d’Andrologie de Langue Francaise Issy-Les-Moulineaux 9-11 Décembre 1999
Résumés des communications orales et affichées 相似文献5.
Resume L'analyse radiocristallographique de diverses Phéophycées a révélé la nature des substances insolubilisées a l'intérieur du thalle et formant des elorescences au cours de la dessiccation.Le D-mannitol cristallise essentiellement sous la forme monoclinique, les variétés et ß orthorhombiques apparaissent plus rarement toujours en faibles quantités.L'examen röntgénographique et les analyses quantitatives montrent que les chlorures de sodium et de potassium se déposent à la surface en proportions qui reflètent les variations de composition du thalle. Les valeurs du rapport Na+/K+ sont caractéristiques des diverses familles.
Summary An X-Rays analysis of various Phaeophyceae has revealed the nature of substances inside the thallus becoming insoluble and efflorescing during drying.D-Mannitol cristallizes essentially in monoclinic form, and ß orthorhombic varieties appear less frequently.Röntgenographic examination and quantitative analysis show sodium and potassium chlorides forming a surface deposit in proportions correlated with the variations of the chemical composition of the thallus. The values of the ratio Na+/K+ are typical of the various algal families.相似文献
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Four aspects of the synchorology of plant communites along the European coastline are treated: (1) with examples from sand dunes (Agropyreta and Ammophileta) and salt marshes (Puccinellieta maritimae) synvicariance is elucidated; (2) The increase in synvicariance towards the inner sand dunes is discussed as a result of an increasing effect of autochthonous climatic features; (3) with examples from sand dunes and cliffs the concept of synendemism is elucidated; (4) synvicariance at the landscape (geosigmetum) is discussed with examples from the French coastline. 相似文献
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Henri Malandain 《Bio Tribune Magazine》2003,6(1):27-29
Le risque pour une personne de développer des manifestations allergiques est plus grand si elle a des antécédents familiaux
d’allergie: on parle de terrain atopique. 相似文献
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Ethel Szerman 《Andrologie》2003,13(2):134-138
Intracytoplasmic sperm injection (ICSI) and testicular biopsies (TESE) have revolutionized the treatment of male infertility, introducing a risk of an increased frequency of genetic defects in the offspring. These risks and their consequences must therefore be evaluated when proposing ICSI to an infertile man. Karyotype and molecular analysis should be performed to detect any genetic defects responsible for male infertility. Y microdeletion screening is important, not only to define the aetiology of spermatogenic failure, but also to provide information allowing a more appropriate management of both the infertile male and his future male child. Genetic counselling is then advised before deciding to attempt ICSI. 相似文献
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The aim of the present study was to investigate the contribution of the single photon emission computed tomography/computed tomography (SPECT/CT) in cancer patients and to evaluate its ability to correctly classify indeterminate lesions on planar bone scintigraphy (PBS).MethodsFrom November 2006 to August 2007, all patients with confirmed malignancy, whose PBS showed indeterminate lesions, underwent without delay a SPECT/CT. The study included 120 patients (67 men, 53 women), with a mean age of 69 ± 12 years (range 42–96 years). The patients with obvious metastases, important pains or who did not accept the examination were excluded from the study. The location of the lesions was described either as precise, probable or indeterminate. The lesions were classified either as definitely malignant, definitely benign or indeterminate.ResultsBreast, prostate, lung and kidney neoplasms represented approximately 80% of all cancers. The PBS highlighted 267 lesions of location either as precise (n = 29), probable (n = 129) or indeterminate (n = 109), classified either as definitely malignant (n = 28), definitely benign (n = 27) or indeterminate (n = 212). The SPECT/CT revealed 440 lesions, of location either as precise (n = 353), likely (n = 39) or indeterminate (n = 48), classified either as definitely malignant (n = 84), definitely benign (n = 305) or indeterminate (n = 51). Thoracic and lumbar spine and pelvis were the locations of 79% of the scintigraphic lesions and of 88% of the osseous metastases. SPECT/CT modified the final report of 80 patients, by excluding from metastases (n = 2), by showing metastases (n = 23) and by showing the benign character of indeterminate lesions (n = 55). Moreover, 69 patients out of 120 (> 57%) had an evolution confirmed with 35 true positives, 31 true negatives, one false negative and two patients with indeterminate lesions on SPECT/CT, without osseous metastasis.ConclusionThe assessment of the indeterminate scintigraphic lesions of oncologic patients benefits from the SPECT/CT. The lesion-based analysis showed that the SPECT/CT detected more lesions (+64%) and correctly classified 88% of the detected lesions. The patient-based analysis highlighted that SPECT/CT modified the final report for more than 66% of the patients. The follow-up showed that SPECT/CT correctly classified for more than 95% of the patients. 相似文献
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H. R. Oppenheimer 《Plant Ecology》1961,10(3-4):247-256
Conclusions phytogéographiques et écologiques Nos observations démontrent que les terrains légers de la plaine littorale ne sont pas seulement aisément reconquis par la flore indigène qui se compose d'éléments méditerranéens, steppiques-orientaux et désertiques africains; ils permettent aussi le développement plus ou moins normal d'espèces ligneuses subspontanées à distribution pantropique (Ricinus, Dodonaea), sud-américaine (Schinus, Lantana etc...) et australienne (Acacia) à condition que leurs caractères biologiques de dissémination et de germination permettent leur établissement et qu'elles soient résistantes à la sécheresse estivale prolongée.
Avec 7 photographies 相似文献
Summary Observations in abandoned citrus groves near Rehovot led to the conclusion that, in the course of 20–25 years, climatic biocenoses of the light soil belt, as Helianthemetum elliptici and the Eragrostis bipinnata-Centaurea procurrens association are reproduced. The starving trees are replaced by indigenous and exotic shrubs and climbers, the former often of a leafless or thorny appearance. Of special interest is the spontaneous expansion of arboreal indigenous species, like Retama roetam, Zizyphus spina christi, Ceratonia siliqua and exotic ornamentals, such as Lantana camara, Schinus terebinthifolius and Acacia cyanophylla, the latter two forming dense natural stands. Distribution by birds plays a major role in the replacement of the citrus trees by species better adapted to the semi-arid surroundings.
Avec 7 photographies 相似文献
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