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1.
《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   

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3.
《Médecine Nucléaire》2014,38(6):429-438
Purpose(1) Evaluate the reproducibility of segmentation methods depending on the preselection region for tumour volume determination on 18F-fluoro-ethyl-tyrosine (FET) PET. (2) Evaluate the intra and inter-operator reproducibility of the manual delineation. (3) Compare this delineation with the segmentation methods.Materials and methodsEighteen FET PET of patients with glioblastoma were analysed. Preselection regions were determined prior to any segmentation. Two physicians delineated the tumour volume manually. The tumour volume was also delineated with a threshold method (40 and 70% of SUVmax), and a random walk based method. Pearson coefficient (r) (P < 0.05 for r > 0.468) and Jaccard indices (JI) were used to compare the volumes.ResultsManual delineation was reproducible with r = 0.97 and IJ = 0.65 for intra-operator, and r = 0.76 and IJ = 0.45 for inter-operator reproducibility. The preselection regions for a given lesion were different and the segmentation varied with the preselection region: r = 0.55 JI = 0.58; r = 0.85 JI = 0.83; r = 0.70 JI = 0.39 respectively for the threshold of 40%, 70% and the random walk. The segmentation differed form de manual delineation with r = 0.37 and JI = 0.16; r = 0.54 and JI = 0.42; r = 0.43 and JI = 0.37 respectively for the threshold of 40%, 70% and the random walk.ConclusionThe reproducibility of the segmentation methods depends extensively on the preselection region. The intra-operator reproducibility of cerebral lesion delineation on FET PET is satisfactory. The inter-operator reproducibility could be improved.  相似文献   

4.
Résumé On décrit deux moyens de réalisation de microculture dans l'identification de champignons filamenteux qui sont comparés avec la méthode classique. Le premier d'entre eux se réalise par ensemencement moyennent l'inondation du milieu en boîte de Petri avec suspension de spores et est ensuite coupé en carrés que l'on place à l'intérieur de boîte de Petri. Le second consiste à suspendre micelium fongique en milieu fluide à 50°C. Les deux ont l'avantage de la rapidité de réalisation, surtout quand on doit préparer un grand nombre de microcultures dans le but de l'enseignement et que l'on ne dispose pas des éléments stériles pour la réalisation de la microculture sur les lames.  相似文献   

5.
Seven years after the publication of the first diagnostic reference levels (DRL) order, the analysis of the data allows the French Institute for radiation protection and nuclear safety (IRSN) to assess and evaluate the increase of the nuclear medicine departments involvement and of the level administered activities to the patients during the most common examinations performed in France. IRSN analyses show a good agreement between the distribution of transmitted examinations and the frequency of examinations performed in France, taking into account 95% of the number of examinations and 95% of the dose delivered to patients by nuclear medicine. These analyses highlight the necessary consistency between DRL regulation, the French society of nuclear medicine (SFMN) recommendations and national practice. The IRSN recommendations established from data analyses have leaded the authorities to publish a new DRL order in January 2012. This first update of the regulation takes into account actual clinical practice in nuclear medicine and introduces fundamental points as pediatric DRL. In the future, periodical updates will be implemented in order to take into account procedures and devices evolutions.  相似文献   

6.
《L'Anthropologie》2021,125(5):102957
Tokai area is situated in the middle of Japan and has various configurations of ground. The eastern area has thick natural layers with volcanic ash which has been supplied from Mt. Fuji. About five chronological stages of Paleolithic culture from trapeze and edge-ground axe culture to microlith culture through backed blade culture have been found in the layers. These stages of Paleolithic culture are indicators of chronological studies in Tokai area. On the other hand, it is difficult to advance chronological studies in the middle east, middle, and west areas, because they have little thickness of layers with volcanic ash. However, different Paleolithic artifacts are found in top and bottom layers which put the AT layer between at Tsubakibora Site in Gifu Prefecture, and they have helped very much chronological studies of Paleolithic culture in the west area. Here is the first result of Paleolithic studies in Tokai area with artifacts which have been found on the forth layer of scoriae at Idemaruyama Site are dated about 35,000 years, one of the oldest Paleolithic culture in Japan. In addition, some lines of pits which were dated 30,000 years were found at Hatsunegahara Site, and they provided valuable data to study Paleolithic hunting. Finally, a holed pendant which had 10 notches on one side was unearthed from Fujiishi Site, and it was dated 19,000 years ago. At Terada and Hino Site, a flat big stone which had carvings was found, though the shape and use were seemed to be different from the pendant at Fujiishi Site.  相似文献   

7.
PurposeDesign a system of delayed telesonography between expert center and isolated site where there is no sonographer.Materials and methodsA motorized probe holder printing a movement of TILT (± 40°) to any 2D echograph probe available in an isolated site, allows a non-sonographer to capture the patients’ whole organ images. This volume of images is sent to the expert center via internet. The video sequence is decomposed into images in the JPEG format by the software VirtualDub. A post-processing software (ECHO-CNES) allows the expert to find the incidences necessary for the diagnosis. This system has been tested on 50 patients at the CHU Trousseau (Tours, France).ResultsOrgans investigated were liver, portal vein, gall-bladder, kidneys (right and left) and spleen. The acquisition time of the volumes of images was 4 min maximum and allowed to reconstruct images necessary for the diagnosis in 80% of the cases. Scanning duration lasted 4 s on average; processing duration of the volume of images lasted approximately 15 min.ConclusionThis system is in validation in real situation in Togo with the aim of its generalization for medical care according to the obtained results.  相似文献   

8.
In botany tentative attempts have been made to classify species, based not on the plant as a whole, but on a particular character, for example pollen characteristics. Pollen, which is involved in the transmission of male genetic information during sexual reproduction, is of particular interest in distinguishing plants and their relationships.

These characters, observed in photon- and scanning electron- microscopy are symmetry, form, number and position of germinating areas. Being genetically stable for a given species, they identify a plant.

Recently, a novel character has been added: the concentration of elements in the exine, determined by electron probe micro-X-ray analysis. It is interesting to follow relationship of plant species, based on the mineral composition of their pollen as a whole, taking into account both plastic and oligoelements, obtained via an inductive coupled plasma spectrometer. Samples of pollen from different plant species, at distinct taxonomic levels, were analyzed; the results were submitted to a normalisation procedure and the standard patterns obtained were investigated by means of a number of numerical techniques (clustering and factor analysis). The aim was to establish if elements could be considered as chemical markers in plant cladistics. The mineral composition in a given species appeared quite stable and this furnished a convenient identification-critorion.

This approach further allows a chemo-taxonomy of species, in as much as organization of families, and perhaps orders, would conform to the phylogenetic proximity-criterion. Hence, we found clusters including pollen of Gramineae, Coniferae, Betulaceae…

This methodology, that should be completed and corroborated on a wider range of samples would provide an original responsee to the problems of identification and classification encountered in a pollen bank. It follows that:

Hence, the working hypothesis that the chemical markers and, in particular, oligo-elements, complete pollen typologies based on morphological and structural characters, appears quite reasonable.

In conclusion, this paper brings a complement to the mineral composition of the exine.

En botanique, des tentatives ont été faites pour classer les espèces non plus à partir d'individus pris dans leur intégralité, mais sur la base d'une de leurs particularités, par exemple à partir des caractéristiques offertes par les pollens. Ainsi, le pollen, dont le rôle est de transmettre l'information génétique mâle de la plante au moment de la reproduction sexuée, présente des caractères de premier ordre utilisables pour distinguer les différentes plantes et pour situer leur parenté et leur filiation.

Ces caractères, que l'on observe en microscopies photonique et électronique à balayage sont la symétrie, la forme, le nombre et la position des zones germinatives. Pour une espèce génétiquement stable, ils constituent la carte d'identité de la plante.

Il est intéressant de continuer à explorer la voie de la structuration des espèces végétales basée sur la connaissance chimique du pollen en déterminant sa composition en oligo-éléments par l'utilisation d'un spectromètre à plasma à couplage inductif. Ainsi, des échantillons de pollens appartenant à diverses espèces végétales situées à différents niveaux taxinomiques ont été analysés et les résultats normalisés sous forme de profils standard ont été soumis à différentes techniques d'analyse statistique mathématique (classification automatique et analyse factorielle). Le but de cette approche est d'apprécier l'aptitude des éléments minéraux à être des marqueurs chimiques en cladistique végétale.

Les résultats obtenus ont permis de constater la relative stabilité du profil en composition minérale au sein d'une même espèce végétale, ce qui donne accès à un critère d'identification commode.

Cette approche permet d'autre part une chimiotaxinomie des plantes étudiées.

Cette approche méthodologique semble susceptible d'apporter une réponse originale aux problèmes de conservation. Les pollens conservés doivent avoir la même composition minérale que les pollens frais.

— the pattern of pollen composition of oligo-elements, calcium and magnesium is a marker in plant cladistics. Since a typology depending on proximity is found between plant species, families and orders.

— an unknown pollen sample may be located, tentatively, on the base of a described model of pollen relation (shortest connexion network — Prim algorithm — and pollen of Bactris-oil palm and Phoenix dactylifera).  相似文献   

9.
《IRBM》2008,29(1):7-12
The aim of this study was to evaluate the impact of different densities on MC3T3 cells attachment onto polyethylene terephthalate (PET) film surfaces. Biomimetic modifications were performed by means of a three-step reaction procedure: creation of COOH functions onto PET surface, coupling agent grafting and finally immobilization of peptides. The originality of this work consist, in one hand on quantifying RGD peptides densities grafted onto PET, and on the other hand on studying MC3T3 cells responses after seeding on such biomimetic surfaces. After each functionnalization step, modifications were validated by several physicochemical techniques: X-Ray Photoelectron Spectroscopy permitted to prove the grafting and high-resolution β-imager coupled with use of radiolabelled amino acids served in evaluation of peptides densities. Moreover, this last technique permit us to ensure stability of binding between peptides and polymer. The efficiency of this new route for biomimetic modification of PET surface was demonstrated by measuring the adhesion at 15 hours of osteoblast like cells. Study of cellular comportment was realized by means of focal contact proteins (vinculin, actin) immunostaining.  相似文献   

10.
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   

11.
IntroductionAcute pyelonephritis is responsible for significant morbidity during the acute phase and distant irreversible kidney damage. However, diagnosis is often difficult in children. The aim of our study was to evaluate in children hospitalized for suspected acute pyelonephritis prevalence of acute lesions revealed by scintigraphy with 99mTc labeled dimercaptosuccinic acid (DMSA) and the relationship between renal parenchymal lesions and different clinical factors and biological risks.MethodsThis is a prospective study collecting 40 children admitted with suspected infection of the high urinary tract. All have benefited from DMSA renal scintigraphy.ResultsThe average age of our patients was 3.25 years. The DMSA scan showed signs of acute pyelonephritis in 32.5% of cases. Taking this examination as a reference, fever was the most sensitive clinical signs (76.9%), but the specificity was only 48.1%. CRP (≥ 20 mg/mL) was the most sensitive (92.3%) but with a specificity of 40.7% organic signs. A high CRP was associated with acute pyelonephritis significantly (P = 0.0033). Sixty-three percent of refluxing kidneys were associated with acute pyelonephritis versus 20.8% of non-refluxing kidneys, with a significant difference (P = 0.007).ConclusionIn case of urinary tract infection in children, a complete clinical and laboratory table may be sufficient to retain the diagnosis of acute pyelonephritis. However, this possibility is rare. In the opposite case, a DMSA scan should be performed to confirm the diagnosis.  相似文献   

12.
Semen analysis is subject to great variability, partly due to the mechanism of ejaculation. This variability can be reduced by taking certain precautions, such as interviewing the patient to eliminate any external factor of variability, by imposing a 3- to 5-day period of sexual abstinence, by explaining the procedures to avoid bacterial contamination of the sample, by verifying whether the whole semen sample has been collected, by checking that the temperature of the sample is maintained at 37°C and finally, by carefully homogenising the sample to obtain good quality liquefaction.  相似文献   

13.

Introduction

In obstructive azoospermia (OA), even if spermatozoa recovery rate are high, pregnancy rates could be lower as expected. When almost surgeons stop if they could find motile spermatozoa in the epididymis after microsurgical epididymal sperm aspiration (MESA), in our center, we add systematically a testicular biopsy with testicular sperm extraction (TESE). What are our sperm extraction rates in MESA or TESE? Are pregnancy and miscarriage rates different regarding the sperm origin?

Material and methods

A retrospective study including 48 infertile couples with ICSI because of OA. Between 2003 and 2011, each patient had a complete aetiological exploration and a surgery with the association of MESA and TESE. ICSI were asynchronous. Each time it was possible, ICSI was realized first with epididymal spermatozoa.

Results

For 48 couples, 99 ICSI were realized. Fifteen couples had 24 ICSI-TESE because no spermatozoon was found in MESA. Eleven couples had 20 ICSI-TESE because of bad quality of sperm recovered with MESA. Twenty-two couples had 22 ICSI-MESA in first intention. If failed, 11 couples had continued with 12 ICSI-MESA and 10 with 20 ICSI-TESE. Although the number of injected oocytes (7,1±4,1 vs 6,9 ±3,6 P: 0,8) and embryos (4,5±3,0 vs 4,7±2,7; P: 0,7) were not significantly different in the two ICSI groups, the number of top quality embryos (2,4±1,9 vs 3,6±2,0 P: 0,005) and frozen embryos (0,9±1,8 vs 1,7±1,9 P: 0,04) were higher in the ICSI-TESE group. Pregnancy rate per punction (58,5% vs 26,5%, P: 0,002) was higher when testicular spermatozoa were used.

Conclusion

Our approach is original with the systematic association of MESA and TESE for each OA man, when others stop surgery when they can find spermatozoa with MESA. We found that more than the half of epididymal explorations were not useful because negative or of bad quality. Embryo quality and per punction pregnancy rate were better with testicular spermatozoa. Association of MESA and TESE could improve the management of these infertile men without exposing them to an over surgical risk.  相似文献   

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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   

16.
M. Gilbert 《PSN》2007,5(1):72-76
The question of personal identity is central to any reflection on mankind and, therefore, immediately relevant to clinical anthropology. The notion of the continuity of personal identity over time represents Ric?ur’s contribution to the question. Upheaval and continuity in life are integrated into self-narrative, enabling temporal permanence of identity, which generates reflective consciousness and its concomitant ethical dimension. But from this anthropological point of view, the subject doesn’t construct a self and world through narrative. On the contrary, it is narrative elements that construct the subject, allowing the subject to make sense of his or her subjective life in the world. Through this narrative conception of the suffering individual, Ric?ur makes a distinct contribution to discourse in clinical anthropology in positing that suffering is a part of a person’s effort to recount their lives.  相似文献   

17.
《L'Anthropologie》2021,125(4):102922
The mammoth bone dwelling no 1 of the site of Mezine, excavated and dismantled in 1954–55 by I. Chovkoplass, is an emblematic and historical reference for the discovery of palaeolithic dwelling structures and in particular mammoth bone dwellings of Eastern Europe. It was the subject of synthetic publications by I. Chovkoplass (1965) and I. Pidoplichko (1969) and a reconstruction at the Museum of Zoology in Kiev. The dwelling no 1 is revised here directly from the excavation documents archived at the Institute of Archaeology NAS Ukraine. The consequences of its collapse, following its abandonment, on the spatial distribution of the mammoth bones are highlighted. The principles of its architecture are specified. And the hypotheses of elevation reconstruction are discussed in light of recent excavations of other sites with mammoth bone dwellings.  相似文献   

18.
Résumé Les variations du volume du protoplasme pendant le développement ont été suivis chezD. virilis etD. melanogaster. Le protoplasme de l'uf fraîchement pondu remplit la membrane vitelline; bientôt, il se produit une contraction de volume, et il se forme un ellipsoïde. Le protoplasme continue à sa contraction pendant quelque temps, puis il se produit à une augmentation de volume. La projection des cellules polaires se fait immédiatement après cette augmentation. Celle-ci est élevée après la formation des cellules polaires et le volume atteint alors un maximum. Pendant cette période, la formation du blastoderme s'accomplit. Ensuite, pendant la période de la formation de la gouttière ventrale, le volume de l'embryon se réduit à nouveau; mais cela la contraction se limite à la partie céphalique seulement. Dans l'embryon létal nullo X, la contraction et l'augmentation de volume se font comme dans l'embryon sain, bien que les noyaux n'exécutent pas leur migration centrifuge. La relation entre la variation de volume et la migration des noyaux est discutée.  相似文献   

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20.
Osteochondritis, or Legg-Calvé-Perthes disease (LCP), is a necrosis of the proximal femoral epiphysis. This vascular accident entails on the complex phenomenon of growth of the child's hip and can result in deformations or even a strict destruction of the proximal femoral epiphysis. The aim of this article is to show the interest of the bone scintigraphy (BS) in precocious diagnosis and follow-up of LCP disease. In this aim, we introduced a clinical case of LCP disease where BS allowed a precocious diagnosis and a strigent monitoring. Discussion of case includes a systematic review of literature.  相似文献   

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