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1.
《Comptes Rendus Palevol》2003,2(5):317-324
Application of the fuzzy set theory to the biometric evaluation of the species Nummulites millecaput in the western part of the Tethys. The goal of this paper is to demonstrate the ability of the fuzzy-set theory to contribute to the evaluation of paleontological problems. As an example, the species Nummulites millecaput, Boubée has been chosen. One hundred specimens of this species, collected from four localities (Arrimblar, Adelholzen, Dudar, and Mount-Kotuc) have been prepared (equatorial sections) for the biometric measurement of the external and internal characteristics. First a traditional statistical evaluation was performed, followed by the construction of membership functions, the latter ones expressing in the best way the transitions from one locality to the other. The results of this evaluation confirmed that from Aquitaine (France) to Armenia, the same species – Nummulites millecaput – was distributed during the Eocene. To cite this article: G. Bárdossy et al., C. R. Palevol 2 (2003).  相似文献   

2.
E. Deniau  D. Cohen 《PSN》2007,5(2):109-116
European and US drug regulatory authorities have recently warned against the use of selective serotonin reuptake inhibitors (SSRIs) in childhood and adolescent depression. Through an extensive literature review on the use of SSRIs to treat depression in children and adolescents — including psychiatric clinical trials, pharmacology, and drug safety data — we will: i) describe the main arguments justifying various regulatory decisions; ii) present published data and subsequent meta-analyses; iii) discuss how to integrate the recommendations into daily clinical practice, freeing professionals from a Manichean approach. We reach the limits of evidence-based medicine, which provide the basis of the scientific work of the regulatory authorities.  相似文献   

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Routine semen examination does not identify minor malformations of the sperm nucleus and chromatin architectural defects, which may be associated with ART outcome and cannot be detected by the embryologist even at 1000x magnification. Recent publications have demonstrated the advantages, compared to routine analysis, of a new method of real-time detailed morphological evaluation of motile spermatozoa: motile sperm organellar morphology examination (MSOME). MSOME is performed with an inverted light microscope equipped with high-power differential interference contrast optics enhanced by digital imaging to achieve a magnification of 10000x. To be considered morphologically normal, a sperm nucleus must have both a normal shape and a normal chromatin content. The aim of the present study was to combine MSOME and sperm DNA fragmentation characteristics to assess reproductive outcome. The study population consisted of the male partners of 52 couples referred for conventional IVF or split cycles (half IVF-half ICSI cycles) and exhibiting normal routine sperm parameters. Spermatozoa were analysed by examining the fine nuclear morphology and DNA integrity using the sperm chromatin dispersion test (SCD test), based on the principle that the deproteinized nuclei of spermatozoa with nonfragmented DNA show extended halos of DNA dispersion that are either absent or only minimally present in sperm nuclei with fragmented DNA. Fertilization rates were significantly lower in the group showing less than 8% of normal spermatozoa according to MSOME criteria, but early embryo development was not affected. Fine sperm morphology correlated with DNA fragmentation rate. These results demonstrate that the assessment of sperm nuclear normality by MSOME analysis and SCD test improves characterization of the semen sample and should be evaluated as a tool for allocating patients to specific assisted reproduction treatments.  相似文献   

5.
Du fait de l’histoire géologique des Mascareignes et des trajectoires cycloniques dans le sud-ouest de l’océan Indien, l’affinité de la faune odonatologique de la Réunion est essentiellement mauricienne. L’étude de la distribution des Odonates en fonction des différents écosystèmes aquatiques de l’île montre que: 1. Les espèces indigènes ayant une vaste répartition géographique se rencontrent essentiellement dans les écosystèmes ouverts de basse et moyenne altitude (de 0 à 800 m d’altitude). Ces écosystèmes peuvent héberger jusqu’à 13 espèces et possèdent les plus fortes densités odonatologiques. 2. La faune odonatologique de la Réunion se distingue de celle des autres îles de la sous-région malgache par la présence de deux espèces continentales cantonnées à des altitudes supérieures à 1000 m. 3. Les espèces endémiques fréquentent surtout les écosystèmes forestiers. Ces écosystèmes ne présentent au plus que cinq espèces de la faune odonatologique de l’île. En définitive, il apparaît donc que la spéciation des Odonates à la Réunion ne se fait pas dans les écosystèmes diversifiés comportant des espèces à large répartition géographique, mais dans un ensemble d’écosystèmes marginaux à faible diversité odonatologique.  相似文献   

6.
The human lineage has a very ancient origin, as most of the mammals. Its oldest representatives, anthropoid primates, have been described from Asia some 45 million years ago. During this long evolutionary story, two critical stages have appeared as especially important, their beginning in Asia and the emergence of hominids in Africa, some seven million years ago. These two stages are discussed hereby with new data relative to their Asian origins and their dispersal into Africa between 45 and 40 million years ago. Following this dispersal event, these primates evolved in Africa and gave rise to the early hominids. These appeared around seven million years ago and have three distinct representatives. Among them, Toumaï appears as the oldest and the closest to our ancestry, a point that is evidenced here.  相似文献   

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J. Auger 《Andrologie》1997,7(4):433-442
Several studies have shown a good correlation between sperm motility and fertility though the microscopic evaluation of the percentage of motile sperm is highly subjective by nature. Therefore in the last decade, various objectives methods have been proposed to overcome this problem. Two types of methods were developed: The methods based on the analysis of images obtained by microphotography, microcinematography and microvideography and the global, undirect methods based on physical principles. Several systems based on video and image analysis (Computer Aided Sperm Analysis, CASA) have been developed and are used in numerous laboratories of reproductive biology. CASA technology offers the possibility to analyse some characteristics of sperm motion which are related to the fertilization potential and to develop new parameters related to some important aspects of sperm behavior such as hyperactivation. However, there is a large amount of interactions between the operator and the CASA machine. CASA instruments are not “ready-to-use” robots: the reliability of CASA depends largely on the expertise and training of the user and the application of standardized procedures and quality control schemes. By contrast, there is only minimal interaction between the operator and the Sperm Quality Anlyser which is a new device measuring and index of sperm motility highly correlated to the concentration of progressively motile sperm. The device uses light passed through a small sample of semen introduced in a capillary tube to detect variations in optical density that result from moving particles. The reproducibility of the measurements is excellent, the device is easy to use and this is a potentially useful tool for field-work studies. Further investigations of this device in the managment of male infertility is warranted. Finally, both types of objectives approaches are complementary to the conventional analysis of sperm motility and they will not replace it. Standardized procedures have been proposed by the World Health Organization for the subjective evaluation of sperm motility. Such procedures are very useful to reduce significantly the intra- and interlaboratory variations but internal and external quality controls schemes indicate that they are not sufficient to achieve acceptable levels of variation and regular quality controls followed by the definition and the application of corrective procedures are required.  相似文献   

11.
《L'Anthropologie》2017,121(3):243-254
Hanshui River valley is a frequently human active region. Early human left rich stone artefacts in this region. A number of Palaeolithic sites are distributed in the upper reaches of Hanshui River valley. As yet, there are about 40 handaxes sites. The material of handaxes in. Hanshui River valley is mainly the siliceous lime stone, quartzite, sandstone, tuff, etc. Handaxes made on pebble are in a higher proportion than those made on flake. The shape of handaxes is mainly triangular and ovate. The retouch technique is direct hammer retouch, lacking soft hammer retouch. These handaxes are retouched according to function and the blank's shape. Most of the handaxes don’t retouch on the handle. This is the character of handaxes in China. The discovery of handaxe industry in China poses a question: the origin of this industry is from Africa or Asia? In our opinion, the handaxes discovered in China are very similar to the Acheulian handaxes in European and South Korea, but its different from that in Africa. The main reasons contributed to the difference are the environment, the stone material and technical method etc. So I think the handaxe industry in China was born locally. It is very important for us to study Palaeolithic culture in Asia and Europe.  相似文献   

12.
Resume Les expériences ont porté sur des lapins repartis en deux groupes parallèles — un groupe étant traité avec des aéroions négatifs en concentrations moderées (n = 10 – 40.000; n+ = 1.000) et l'autre sans aéroionothérapie (témoins). Par rapport aux animaux témoins (pas exposés aux aéroions),on a enregistré,sous l'influence de l'aéroionothérapie, que: (1)il y a une tendence de normalisation de la motilité spontanée, deprimée par une alimentation contenant un excès de cholestérol(0,3 g/kg/jour); (2) la lipémie et la cholestérolémie sont restées à un niveau plus bas chez les animaux alimentés au cholestérol; (3) la lipémie et la cholestérolémie, de même que l'iode thyroïdien, sont restées aux valeurs voisines de celles normales,chez les animaux nourris avec un excès (20 mg/kg/jour), de substances antithyroïdiennes naturelles (provenant du chou).
Groups of rabbits were exposed to negative air ions of moderate concentrations (n = 10 – 40,000; n+ = 1,000) while others served as controls. (1) When rabbits were fed a cholesterol-rich diet (0.3 g/kg/day)causing reduction of motility in the control animals, their motility was normalized under air ion treatment. (2) The blood cholesterol and lipid levels of rabbits on a cholesterol-rich diet were lower with air ion treatment than in controls.(3) When rabbits were fed a diet with thyroid blocking agents from cabbage the blood cholesterol and lipid levels and the thyroid iodine content remained unchanged with air ion treatment.

Zusammenfassung Gruppen Kaninchen wurden mit negativen Luftionen in mässigen Konzentrationen (n = 100 000 – 40 000; n+ = 1 000) behandelt, während andere als Kontrollen dienten. (1) Die durch Fütterung von cholesterinreicher Diät (0,3 g/kg/Tag) verminderte Motilität der Tiere wurde unter der Luftionenbehandlung normalisiert. (2) Der durch Fütterung von cholesterinreicher Diät erhöhte Blutcholesterin- und-fettspiegel fiel durch Luftionenbehandlung ab. (3) Der durch Fütterung von strumipriven Substanzen aus Kohl erhöhte Cholesterin- und Fettspiegel im Blut und verminderte Jodgehalt der Schilddrüse wurde durch Luftionenbehandlung nicht beeinflusst.
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13.
《L'Anthropologie》2018,122(4):654-678
Abrigo de la Quebrada offers an exceptional sequence with nine occupation levels which seven belongs to Middle Paleolithic. The division between levels II to V and VII to IX by a sterile level VI allow us to study diachronic changes on raw materials and knapping systems. This data is compared with other contemporary sites to evaluate technological trends and the raw material availability in the central region of Mediterranean area.  相似文献   

14.
PurposeThe aim of the study was to evaluate the diagnostic performance, the prognosis factors and the therapeutic impact of 18F-FDG positron emission tomography (FDG-PET) in the detection of recurrent colorectal cancers.MethodsSixty PET/CT with 18F-FDG and CT were performed in 52 patients, at the Paul Papin cancer center between 2003 and 2005, following suspicion of colorectal cancer relapse. The FDG-PET impact on the clinical management was studied by examination of multidisciplinary concertations results. Survival analysis were realized with a mean follow up of 2.2 years.ResultsRecurrence was confirmed for 50 explorations by histologic (n = 32), radiologic (n = 14) or clinical (n = 4) findings. Twenty patients died during the time of the study. On a patient based analysis, FDG-PET sensitivity, specificity and overall accuracy were 90, 90, 90% respectively compared with 74, 50 and 70% for CT. FDG-PET changed the clinical management in 18 cases (30%). A positive FDG-PET signal, more than one hepatic lesion, more than two lymph node lesions detected on FDG-PET and more than two hepatic lesions on CT were characterized as bad prognostic factors for survival. Multivariate analysis showed that the only independent bad prognostic factor was the FDG-PET detection of more than two liver lesions.ConclusionThese results confirmed the important impact of FDG-PET in the clinical management of patients with a suspected recurrence of colorectal cancer.  相似文献   

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Résumé Le virus de la densonucléose est thermorésistant. Il n'est pas inactivé après traitement avec des solvants de lipides. Aucun pouvoir hémagglutinant n'a été mis en évidence avec des érythrocytes d'espèces variées. Ces propriétés sont comparées à celles desParvovirus.
Summary The densonucleosis virus is thermoresistant. It is not inactivated after treatment with lipid solvents. Attempts to demonstrate hemagglutination of DNV, using different erythrocytes, were unsuccessful. These properties are compared to those of Parvoviruses.
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17.
Le cancer du col de l’utérus reste un problème de santé publique puisque 900 000 nouveaux cas sont diagnostiqués chaque année de par le monde [Luthra] et il est responsable en France de plus de 1600 décès par an. Pourtant, depuis plus de 40 ans, le dépistage de masse des précurseurs du cancer invasif est tout à fait réalisable et le traitement des anomalies cervicales pré-invasives amène généralement à la guérison.  相似文献   

18.
PurposeThe objective of this study was to retrospectively evaluate the impact of positron emission tomography/computed tomography (PET/CT) using fluorine-18-fluorodeoxyglucose (FDG), in comparison with conventional imaging modalities (CIM), for initial staging and early therapy assessment in paediatric rhabdomyosarcoma.Patients and methodsPrior to treatment, 18 patients (age range, 9 months to 18 years) with histologically proven rhabdomyosarcoma underwent FDG PET/CT in addition to CIM (magnetic resonance imaging of primary site, whole body CT and bone scintigraphy). After three courses of chemotherapy, 12 patients underwent FDG PET/CT in addition to CIM. RECIST criteria and visual analysis of FDG uptake were used for assessment of response. The standard of reference was determined by an interdisciplinary tumor board based on imaging material, histopathology and follow-up data (median = 5 years).ResultsPET/CT sensitivity was superior to CIM's concerning lymph node involvement (100% versus 83%, respectively) and metastases detection (100% versus 50%, respectively). PET/CT results changed therapeutic management in 11% of cases. After three courses of chemotherapy, the rate of complete response was 66% with PET/CT versus 8% with CIM. Five percent of patients relapsed during follow-up (median = 5 years).ConclusionThis study confirms that PET/CT depicts important additional information in initial staging of paediatric rhabdomyosarcomas and suggests a superior prognostic value of PET/CT in early response to chemotherapy assessment.  相似文献   

19.
In this work, we have evaluated the potential of image fusion and attenuation correction (AC) of SPECT-CT imaging for the assessment of gastro-entero-pancreatic endocrine tumors by somatostatin receptor scintigraphy (SRS).MethodAfter optimisation of acquisition and reconstruction parameters, we have evaluated, in a prospective study, SRS performed over a period of one year. We have compared visual interpretations of planar and tomographic images versus SPECT/CT images to determine if anatomical localisation and diagnostic contributions are improved. In a semi-quantitative analysis of pathological foci, we have measured maximal intensity values (Tmax), tumour to background ratios (T/B) and tumour contrasts (Ct) with and without AC.ResultsIn 25 SRS, visual analysis has shown anatomical localisation improvements in 60% of cases (CI95%, 39–79) and diagnostic improvements in 64% of cases (CI95%, 43–82). Doubtful foci proportion changed from 44 to 11%. In the semi-quantitative analysis of 41 pathological foci, Wilcoxon matched-pairs tests showed significantly higher Tmax, T/B and Ct values after AC.ConclusionSPECT/CT imaging improves diagnostic quality of SRS thanks to a better foci localisation and a better lesional contrast in the image.  相似文献   

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The most frequent cause of testicular injuries is blunt trauma (following sports injuries or road accidents). Penetrating injuries are rare. Increased scrotal volume and a painful testis are the main symptoms and require scrotal ultrasonography. Scrotal ultrasonography is very sensitive and specific for testicular rupture or intratesticular haematoma. Two out of three patients with testicular injuries require surgical exploration. Secondary complications due to delayed management of trauma are testicular atrophy, sterility or impotence. Penile fracture (rupture of corpus cavernosum) is due to direct trauma by an excessive force applied to an erect penis. Swelling, penile ecchymosis, penile curvature and pain are the usual symptoms of rupture of the tunica albuginea. Urethral injury must be ruled out. Cavernosography, ultrasonography or MRI are not considered mandatory to establish a diagnosis but can be prescribed in the absence of typical signs or symptoms. Early surgical exploration and repair ensure a better outcome. Secondary complications are penile curvature, chronic pain and impotence.  相似文献   

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