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1.
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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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   

4.
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   

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L. Brunet 《Andrologie》2010,20(1):92-102
This study clarifies the lively debate surrounding the anonymity of gamete donors. This principle, which has not been challenged since 1994, is currently criticized by a number of people, who were conceived through medically assisted procreation technologies with donor and who now have reached adulthood. Their testimony has a very significant impact on French public opinion. Several official reports have already suggested that the anonymity of gamete donors may well be removed under certain circumstances. To understand why public opinion has evolved so dramatically, we must revisit the legal position of gamete donors in the specific context of less visible changes in the law. Indeed, the legal concepts of parenthood and identity have been reshuffled over time, and such changes have deeply affected the legal issues relating to the anonymity of gamete donors. Formerly, the law governing the identification of individuals was shaped by political and social objectives. Now it is more concerned with the sense of identity and personal fulfilment of people. This change, based on modern western notions of egalitarianism and individuality, has dramatically affected the outcome of parenthood trials. Moreover, biological tests have made the truth available like never before. The possibility of finding out the truth has shocked the practice of many areas of family law and has created a new set of challenges, especially when the secrecy of the genetic parents has been legally established. In France, women have traditionally been able to deliver their children anonymously. A deadlock has resulted, which may now be overcome by introducing a new concept of personal origins. Now the law is evolving to permit the children to demand their biological mothers’ identity under certain circumstances, but without affecting anyone’s rights. The concept of personal origins has been quite successful on the European scene and has also charged the debate. It is now recognized under French and European laws that individuals must have privileged access to their personal origins. Can the principle of anonymity of gamete donors remain immune from such a (r)evolution ?  相似文献   

7.
《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   

8.
《Médecine Nucléaire》2017,41(6):397-404
In France, it is required to give patients some written radiation safety advice following an iodine-131 therapy of thyroid. However, there is no regulatory methodology proposed to assess the restriction times required to limit radiation dose received by their family and by third persons. In this study, we compared two methods to perform the calculation of restriction times for differentiated thyroid cancer: the first one, called Global method, follows general recommendations and the second one, called PaDe method, provides customized recommendations based on the effective half-life measured for each patient during the 48 h of hospitalization. For these simulations, the input parameters for both methods were dose constraints, contact patterns, final dose rate measurement at discharge of the patient, effective half-life and dose rate variation with distance. For the Global method, these parameters were set and were not changed. For the PaDe method, the effective half-life and the final dose rate were adjusted for each patient. Comparison between the two methods was carried out for 103 patients. For 68.0 % of the patients, no restrictions were necessary according to the PaDe method whereas the Global method required restrictions to be applied during up to 2 days. For almost 16.5 % of them, restriction times estimated with the PaDe method were systematically lower. For the remaining 15.5 %, at least one contact pattern restriction had to be increased according to the PaDe method. Furthermore, with the Global method, the same instructions were given to 97.0 % of the patients. These results showed the limits of the Global method which does not consider individually tailored biological data. Eventually, the use of the personalized PaDe method optimizes the radiation protection by improving the well being of the patient or reinforcing the family and third person's protection.  相似文献   

9.
Macrobenthic organisms are much used nowadays as bio-indicators for their ability to reflect different disturbances of aquatic ecosystems. However, they have never been used to assess the ecological status of the lagoons of Benin. The current study aims at revealing the ecological state of the lagoon of Porto-Novo through the study of changes in the settlement of benthic organisms collected in this lagoon. The sampling was carried out from July 2007 to June 2009 on a frequency of four seasons of collection per year. The self-organizing map (SOM) of Kohonen has been used for various patterns of distribution of collected organisms. A discriminant analysis (AFD) has allowed the identification of the parameters that govern the patterns observed in this environment. Four groups of macrobenthic communities emerged that were well predicted (75%). The distribution of benthic macro invertebrates of this lagoon is therefore zonal, seasonal and discriminated by variables of mineralization and sediment grain size. The difference in taxonomic richness corresponds to environmental conditions of stations appearing more or less stable and highlighting a gradient of the stress on organisms. Places with unstable conditions are affected by human activities due to their proximity to homes that are enriched in organic matter. These places are full of polluted-tolerant species such as the Gastropods Potamididae, Cirratulidae Polychaetes, Diptera Chironomidae and Oligochaeta. The macrobenthic fauna, which is well differentiated in the groups, is then subjected to human disturbance.  相似文献   

10.
M. Géraud 《PSN》2009,7(3-4):152-158
German psychiatry is one of the areas where we see the development of an unconventional psychiatry, characterized by its reference to philosophical traditions that are remote from the natural sciences, and by its emphasis on the overall nature of the mentally ill person. This approach first emerged during the period of comprehensive psychiatry promoted by Karl Jaspers and Kurt Schneider. This particular form of psychopathology focuses its attention on the inner experience of the ill person and attempts to understand it, in particular through empathy. This approach was soon reinforced by a philosophical method founded by Husserl and further developed by Heidegger: phenomenology. Firstly, this consists of a way of approaching and examining the discrete elements of consciousness, leading to the notion of intentionality (Brentano, Husserl). The central place of consciousness in this approach leads to the questioning of existence and of the person supporting this consciousness: this philosophy thus leads to existentialism (Jaspers, Sartre) and Heidegger’s concept of Dasein (the existential analytic, Dasein’s ontology). Phenomenological psychiatry is thus a clinical science characterized by its approach and its reference to what might overall be described as comprehensive anthropology. There are numerous authors who affiliate themselves with this phenomenological psychology. Our article is devoted to Alfred Kraus’s approach. We will first of all address the notions of comprehensive psychiatry and phenomenology. After introducing Alfred Kraus and the specific philosophical and clinical foundations of his work, we will examine the Krausian theory of identity based on Mead and Sartre, which establishes a distinction between ego-subject (a free element that produces ego achievements) and ego-object (identifications, in particular with social roles in the case of depressives). The ego-subject is the transcendent element (Sartre), which constantly exceeds what I am (ego-object) and there is thus an internal negativity. We will then address the clinical concept of manic-depressive illness. The identity structure of the depressive is characterized by hyper-identification. The notion of psychotic breakdown will then be covered, where it appears that melancholia is not an affective disorder, a mood disorder, but a case of depersonalisation. The personality disorder which precedes melancholia results from a threat that weighs on this fragile identity propped up against its identifications, which is expressed in hypernomic behaviour: this being a reinterpretation of the notions of a specifically depressive temperament, constitution, premorbid personality or typus melancholicus. Hypernomic behaviour is characterized by the scrupulous observance of role expectations and an extreme respect for laws and norms which is expressed as a form of hyperadaptation. Finally, the last part is devoted to the intolerance of ambiguity, which can be cognitive or emotional (the inability to experience negative feelings).  相似文献   

11.
Philippe Huneman 《PSN》2004,2(2):47-60
The author analysesEncyclopédie’s articles devoted to nervous and mental functioning and disorders, showing that a new approach to lunacy as a mental illness, which is defined in some articles as a “general trouble of the animal economy”, progressively emerged. The term,animal economy, unified physical and moral aspects of the study of man. It was elaborated by XVIIIth century physiologists and was widely accepted by French physicians. This idea is based on the vitalistic thought of the Montpellier school, which equated life with sensibility, and on English medical conceptions of a nervous-centred organism. Later on Philippe Pinel’s work displayed the legacy of these conceptions. On one hand, the comprehensive view of physical and moral dimensions in theanimal economy neutralized the question of an organic or psychogenetic origin of madness. This enabled him to consider it as a determinate field of sensibility interactions and as a medical matter, and to legitimize the group of therapeutic practices that he namedtraitement moral. On the other hand, Pinel departed from the classical conception ofanimal economy by developing his concept of aprinciple of mania, which underlies the manifold symptoms and forms of madness, and which are only perceptible to a trained specialist (aliéniste). The historical development analysed in this article show how alienists were enabled to claim both the wholly medical nature of insanity as disease, and their specific competence as apart from the other medical disciplines. To this extent, Esquirol achieved Pinel’s scientific work.  相似文献   

12.
Jean Ritter 《Plant Ecology》1972,25(1-4):357-365
Conclusions L’important mémoire deJ. Braun-Blanquet (1971) sur les Associations des basmarais suisses ainsi que d’autres travaux (E. Oberdorfer, 1970;H. Ellenberg, 1963), permettent d’affirmer que les groupements de l’Eriophorion latifoliae (Br.-Bl. et Tx. 43) et des Caricetalia Davallianae (Br.-Bl. 49) sont représentés dans l’ensemble de la cha?ne alpine sur substrat riche en calcium et, en général, à partir de l’étage montagnard supérieur. Dans les Alpes et Préalpes fran?aises, plusieurs auteurs ont décrit des groupements du Caricion Davallianae (M. Guinochet en Tinée et en Haute-Savoie, 1938 et 1939;G. Aubert, L. Borel, A. Lavagne etP. Moutte dans l’étage subalpin de la feuille d’Embrun-Est, 1965). Dans le Vercors, seuleCh. Faure (1968) signale simplement l’existence du Caricion Davallianae (Klika 34) dans la partie septentrionale du massif (feuille de Vif). Enfin, dans les Préalpes du sud où les étages montagnard et, a fortiori, subalpin sont peu ou pas représentés.A. Archiloque, L. Borel etA. Lavagne (1970) constatent l’absence du Cratoneurion commutati (W. Koch. 28) et du Caricion Davallianae (Klika 34) sur la feuille de Javie (préalpes de Digne). Bien que la nature de la roche-mère soit déterminante pour l’existence des groupements de source et bas-marais alcalins, c’est en définitive la relative permanence de l’alimentation en eau courante et fra?che qui représente le facteur décisif pour ces associations. Dans la région étudiée, celles-ci sont à leur limite méridionale, ce qui confirme—s'il en était besoin—l’originalité et la richesse de ce secteur des Préalpes. Laboratoire de Taxonomie Expérimentale et de Phytosociologie de la Faculté des Sciences de BESAN?ON (25)—FRANCE.  相似文献   

13.
Ejaculated sperm cryopreservation can be proposed in the course of anART procedure, particularly in the case of severe oligozoospermia likely to deteriorate. The aim of this study was to evaluate the influence of the freezing-thawing process on sperm DNA fragmentation (analysed by the TUNEL technique). The first step of this work consisted of adapting the TUNEL technique to perform this analysis on very poor quality sperm. A study was then performed on 72 patients divided into 4 groups according to their spermatic characteristics: group 1 [n=20] (“normal” parameters according to WHO), group 2 [n=24] (normal sperm count associated with asthenospermia and/or teratospermia), group 3 [n=16] (total sperm count between 5 and 20 M) and group 4 [n=12] (total sperm count below 5 M). Spermatic parameters and DNA fragmentation (performed by TUNEL in situ technique, 400 spermatozoa read per slide) were evaluated on raw semen - for all patients -, raw migrated sperm - for patients of group 1 and 2 -, migrated frozen-thawed sperm - for all patients-. A TUNEL technique adapted to oligospermic samples was developed, manipulating spermatozoa directly on the slide rather than in suspension, to limit spermatic sample loss. After the whole migration-freezing-thawing process, the mean DNA fragmentation rate decreased for patients in group 1 (2.9 vs 5.1%, p<0.0001) whereas this rate increased for patients in groups 2 (10.5 vs 6.8%, p<0.0001), 3 (10.7 vs 7.6%, p<0.05) and 4 (15.2 vs 8.7%, p<0.005). DNA fragmentation rates from thawed samples were also correlated with initial spermatic parameters. At the intermediary step, migration decreased DNA fragmentation rate in comparison with raw semen rate in both groups (1.9 vs 4.7% [p<0.05] in group 1; 2.5 vs 5.4% [p<0.05] in group 2). DNA fragmentation rate decreases after migration and then increases after freezing-thawing so that this rate is lower than the raw semen rate for “normal“ sperms and higher than the raw semen rate for altered sperms. Nevertheless, this DNA damage induced by cryopreservation on altered sperms remains moderate. Sperm “resistance” to cryopreservation also appears to depend on spermatic parameters. Cryopreservation may positively select spermatozoa, accelerating elimination of senescent spermatozoa by necrosis, so that early apoptotic spermatozoa from fresh ejaculate are not found in thawed samples. These results, that need to be completed by a study on a larger sample of oligospermic patients, encourage us to continue cryopreserving severely altered sperms.  相似文献   

14.
C. Mathieu  H. Lucas 《Andrologie》1999,9(2):286-296
There are many procedures to select spermatozoa but those procedures are often specific of each andrology centre. This review that is not an exhaustive review of the numerous methods published is rather devoided to focus on the main techniques, the sperm washing, the filtration methods («SpermPrep»), the swim-up, and the discontinuous density gradients with colloïdal solutions («Percoll», PureSperm” and «Isolate») including iodinated organic molecule as ‘OptiPrep». The first part presents a synthesis of literature in order to bring out standardized procedures, and a summary of the advantages and disadvantages of each step of these procedures. Some specific anomalies of sperm need particular treatments. There is a consensus on the validated techniques to prepare semen samples in the presence of antisperm antibodies, leukocytes, bacterial contaminants, and also semen samples exhibiting hyperviscosity or in case of retrograde ejaculation. Cryopreserved sperm preparation is also described with references to experimental results in freezing-thawing human spermatozoa. The second part proposes guidelines for the therapeutic choice of the appropriate assisted reproductive technologies (i.e.: intra uterine artificial insemination, in vitro fertilization or intracytoplasmic sperm injection) according to semen parameters, and to the outcome of sperm selection and survival.  相似文献   

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《Comptes Rendus Palevol》2003,2(2):125-132
Real-time Polymerase Chain Reaction (PCR) for the study of ancient DNA. The properties of ancient DNA (aDNA) make difficult the retrieval of DNA sequence. The advantage of Real-Time PCR was exploited, for the first time, in the study of aDNA. We determined the optimal condition to amplify, in one round of PCR, aDNA, which should be directly sequenced. Beside the verification of aDNA authenticity, we compared two cleaning bone methods: scalpel and ethanol. The ethanol specimens showed the best DNA yield. The aDNA was extracted and amplified (mitochondrial hypervariable region I) from five skeletons exhumed from the archaeological site of Notre-Dame-du-Bourg (France), dated from 3rd to 17th century. To cite this article: R. Kefi et al., C. R. Palevol 2 (2003) 125–132.  相似文献   

18.
Zevalin® (yttrium-90 ibritumomab-tiuxetan) is the first radioimmunotherapy authorized in France for non-Hodgkin's lymphoma (NHL) treatment. It is indicated for clinical use in adults for recurrent or refractory follicular NHL including those refractory to rituximab. Treatment responses are between 70 and 80%. Since three years, 13 patients were treated in Nice by Zevalin®. From this retrospective study, we discuss the various perspectives of this treatment. The majority of our patients in this study were evaluated by 18-FDG–PET and we also evaluated our results in this regard. Even if our follow-up is short, our experience confirms the efficacy and tolerance of Zevalin® treatment in multirecurrent follicular NHL including those refractory to rituximab. The treatment is of interest in elderly patients and in case of autologous stem cell transplant. The proposed « Autorisation de Mise sur le Marché » (AMM) indication is probably not the best one since efficacy seems better in smaller tumour volumes and when used earlier in the therapeutic course. Zevalin® will probably be more beneficial in first line treatment, for immunochemotherapy consolidation and for autologous stem cell transplant conditioning. We pointed out the prognostic value of FDG–PET for early post-treatment evaluation, one to two months after Zevalin® administration. However, larger scale studies are necessary to confirm these findings.  相似文献   

19.
R. Mieusset 《Andrologie》1999,9(2):272-285
Non descended testes in the low scrotum is a common anomaly at birth, with about 4% of the newborn males affected. Only one quarter of these newborn babies will still have non descended testes when one year old. However, the testes that will descend within the first year of life seem no more to be considered as normally descended testes. Moreover, the retractile testis, which represents a secondary anomaly of testicular position occuring after the babies are older than one year, is no more to be regarded as a physiological variant of the normally descended testis, since several reports indicate histological and clinical modifications in such cases. The testicular non descent can be associated with two consequences in adult life. Firstly, an history of non descended testis is the only known risk factor for the testicular cancer. Secondly, such an history is a risk factor for the male fertility because of spermatogenesis alterations, as indicated by qualitative and quantitative histological analyses of the testicular tissue, and by depressed spermatozoa output and quality (motility, normal forms); moreover, testicular volumes are reduced, and the time to pregnancy as well as the rate of infertility are increased. Time is arrived for a reappraisal of the consequences in adult life of the abnormal testicular location (either congenital or acquired) during childhood.  相似文献   

20.
Résumé Les courbes de survie sont obtenues par irradiation gamma, fractionnée ou non, à débit de dose élevé ou faible. Elles portent sur des Chlorelles à l'état quiescent par rapport au cycle cellulaire (cellules en G0). Elles s'expliquent en envisageant trois catégories de lésions par irradiation: les lésions létales d'emblée, les lésions sublétales non restaurables et les lésions sublétales restaurables.
Analysis of clonal survival curves obtained on -irradiated Chlorella cells at several dose rates
Summary The survival curves have been obtained after split or unsplit doses at high or low dose-rate. The living material wasChlorella cells in G0 stage (non-dividing cells). It is possible to explain these curves by the effects of three types of damage: directly lethal damage, repairable sublethal damage and non-repairable sublethal damage.
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