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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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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   

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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.
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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.
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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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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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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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Roussine  N. 《Plant Ecology》1957,7(5-6):291-300
Sans résuméReçu par la rédaction en mai 1954.  相似文献   

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Résumé Pour atteindre les buts visés par le recyclage biologique des eaux usées, il faut exploiter une population d'organismes filtreurs dont l'augmentation nette de biomasse est rapide et importante. L'augmentation nette de biomasse sera favorisée par une croissance individuelle, une reproduction et une survie excellentes dans l'eau usée traitée. L'étude de ces paramèters sur des cohortes de Daphnia magna soumises à différentes conditions expérimentales, indique qu'il s'agit d'un organisme prometteur pour le recyclage biologique. Dans nos conditions expérimentales, D. magna montre un bilan azoté positif durant toute sa vie. La production rapide de biomasse est favorisée par une température élevée (15 °C) et une nourriture abondante. L'eau traité montre les signes d'une certaine toxicité envers les juvéniles mais non envers les adultes. Nos données établissent que la production d'oeufs requiert une taille minimale de la femelle de 2,7 mm, information primordiale pour l'exploitation future de la population.
To realize the objectives of the biological recycling of wastewaters, it is necessary to exploit a population of filtering organisms, the biomass of which shows a rapid and important net increase. The net increase of biomass is favored by excellent individual growth, reproduction and survival in treated wastewaters. The study of these parameters, with cohorts of Daphnia magna submitted to different treatments, indicated that it is a promising organism for biological recycling. Under our experimental conditions, D. magna exhibited a positive nitrogen balance for the whole of its life. The rapid production of biomass was favored by high temperature (15 °C) and abundant food. The treated wastewaters proved to be somewhat toxic to juveniles but not to adults. Our results demonstrated that the egg production requires a female minimal size of 2.7 mm; this information is most important in the future exploitation of the population.
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陈淳 《人类学学报》1998,17(1):73-80
两极法与pièceesquillées@陈淳¥复旦大学文物与博物馆学系两极法与pièceesquilées陈淳(复旦大学文物与博物馆学系,上海200433)收稿日期:1996-09-231前言两极法或砸击法是最原始和最简单的打片方法之一。它被史前人类甚至现...  相似文献   

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Bacterial interspersed mosaic elements (or BIMEs) are repeated sequences identified in several enterobacterial genomes. BIMEs are a mosaic combination of small sequence motifs. It has been estimated that 500 BIMEs are scattered over the bacterial genome. BIMEs have been identified in several enterobacteria: Escherichia coli, Salmonella typhimurium, Klebsiella sp. and relatives of these bacteria. BIME function is not known, but their interactions with specific proteins (DNA polymerase I, gyrase and integration host factor) suggest that they could be involved in functional organization of bacterial chromosomes. Four other families of interspersed repetitive sequences have been shown to exist in a variety of bacterial genomes. Like BIMEs, these sequences are rather small, contain a region of dyad symmetry, and are found in extragenic locations. Unlike BIMEs, IRU (or ERIC), box C sequences and RSA sequences occur in enterobacteria but also in other Gram-negative bacteria.  相似文献   

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Purpose

To assess clinical and therapeutic aspects of penile urethral fistula following circumcision in our daily urological practice.

Patients and methods

We carried out a retrospective study of cases of penile fistula between 1990 and 2007.

Results

A series of 85 cases is reported. The mean age was 10.7 years (15 months-38 months). The circumcision was performed by paramedical persons in the majority of cases. The mean period elapsing before consultation was 4.1 ± 5.3 years (range: 1 week-28 years). The fistula was associated with partial amputation of the glans penis in one case, and with urethral meatus stenosis in three cases. The surgical treatment was layered repair in the majority of cases. The average follow-up was 3.35 years (range: 2 months-8 years). Overall results were satisfactory in 81.2% of cases.

Conclusions

Penile fistula due to circumcision is common in our region. Its management is codified but there is a significant risk of failure, making prevention even more important.  相似文献   

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