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1.
Respiratory motion causes a spread of lesion uptake over a larger area in Positron Emission Tomography (PET) images for moving structures. When CT images are used for attenuation correction of emission data, this motion may alter the quantization of PET images. We present the clinical results of a respiratory-gated PET processing “CT-based” method, which aims to improve PET-CT coregistration by using an additional breath-hold CT (BH-CT). The CT-based protocol consisted in a 10-min List Mode respiratory-gated PET acquisition, followed by an end-expiration BH-CT acquisition. During these two examinations, the respiratory signal was recorded continuously. Eleven pulmonary lesions were studied. Patients underwent both a standard clinical PET protocol (free breathing) and the CT-based protocol. The respective performances of the CT-based and clinical PET methods were evaluated by comparing the distances between the lesions’ centroids on PET and CT images. SUVMAX (Standardized Uptake Value) and volume variations were also investigated. The CT-based method showed a significant reduction (p = 0.049) of centroid distances (mean relative change versus standard method: 49%). We also noted a higher SUVMAX (mean change: 39%). Lesion volumes were significantly lower (p = 0.026) in CT-based PET volumes (mean change: 43%) compared with standard ones. The CT-based method improves PET-CT coregistration of pulmonary lesions. This protocol should lead to more accurate attenuation correction and thus improve SUV measurement.  相似文献   

2.
A ce jour, aucun texte réglementaire ne permet d’obliger le biologiste à mettre en œuvre un système d’assurance qualité adapté à la gestion de la biologie délocalisée. La SFBC a réuni un groupe d’experts afin de formaliser des recommandations dès 1998 [1]. Actuellement, ce sujet est à l’ordre du jour des organismes internationaux, et il est vraisemblable qu’une normalisation interviendra dans le futur, à terme opposable aux biologistes en relation avec un établissement de soins pratiquant une délocalisation des analyses de biologie médicale: une annexe à la future norme ISO/CEN 15189 concernant les recommandations pour la biologie délocalisée est en cours de validation, faisant suite aux recommandations du groupe européen EC4 [2].  相似文献   

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A. Jaylet 《Chromosoma》1971,34(4):383-423
Résumé Chez le Pleurodèle, une étude cytogénétique portant sur quatre géné-rations successives a permis d'obtenir une lignée stable d'individus féconds homozygotes pour une translocation réciproque.L'anomalie a d'abord été décelée à l'état hétérozygote chez une femelle résultant du croisement entre une femelle normale et un mâle irradié aux rayons X. Le remaniement chromosomique initial consiste en un échange réciproque de segments inégaux entre le bras court d'un chromosome 5 et le bras long d'un chromosome 6. Il en résulte un allongement du bras court d'un chromosome 5 correspondant à un raccourcissement d'égale amplitude du bras long d'un chromosome 6, soit la formule 24, t(5p+; 6q-) par analogie avec le système utilisé pour les caryotypes humains.Contrairement à ce que l'on aurait pu supposer, la ségrégation des chromosomes remaniés n'est pas perturbée au cours de la méïose des animaux 24, t(5p+;6q–).Lors des croisements entre un individu hétérozygote pour la trans-location et un individu normal ou entre deux hétérozygotes, la descendance est constituée de germes phénotypiquement normaux ou anormaux selon leur constitution chromosomique.Les sujets 24, t(5p+; 6q–) et 24, 2(5)–, 2(6)–,2(5p+) +, 2(6q–)+ ont un caryotype équilibré, leur phénotype est normal. Les formules déséquilibrées sont par contre léthales ou semi-léthales.Les embryons 24, 6–, (6q–)+ et 24, 5–, 2(6)–, 5p+, 2(6q–)+ présentent rigoureusement le même syndrome. Ils meurent peu de temps après l'éclosion sans pouvoir se nourrir. Les ébauches branchiales sont pratiquement inexistantes, l'il est malformé et la bouche reste béante.Les deux formules 24, 5–, (5p+)+ et 24, 2(5)–, 6–, 2(5p+)+, (6q–)+ déterminent de même un autre syndrome caractéristique. Dans ce cas, chez les embryons âgés et les jeunes larves, les malformations sont discrètes et transitoires. Elles se situent au niveau des yeux et des branchies. Il est difficile d'élever ces animaux jusqu'à l'âge adulte. Ceux qui survivent ont un corps disproportionné et des anomalies du squelette vertébral.Les deux formules 24, 2(6–), 2(6q–)+ et 24, 2(5)–, 2(5p+)+ ont un déséquilibre tel que les embryons ne dépassent pas le stade de la gastrula.L'examen des figures méïotiques de mâles hétérozygotes pour l'anomalie confirme les résultats obtenus à partir de l'étude des phénotypes et des caryotypes des descendants. La première division méïotique comporte 10 bivalents et un tétravalent tandis que l'examen des caryotypes établis à partir des métaphases II montre qu'il ne se forme que quatre types différents de gamètes.Le chromosome 6q– se reconnaissant aisément à l'examen microscopique direct, la translocation constitue un marqueur nucléaire facilement utilisable car les individus homozygotes pour l'anomalie ont une croissance et une méïose normales.
A homozygous reciprocal translocation in a strain of the newt Pleurodeles waltlii
A cytogenic study dealing with four generations of the newt Pleurodeles waltlii has lead us to a stock of fertile homozygotes for a reciprocal translocation. —The chromosomal rearrangement has first been detected at the heterozygous state in a female resulting from a cross between a normal female and a male submitted to X ray-irradiation. The initial aberration consists of a reciprocal exchange of unequal segments between the short arm of a chromosome 5 and the long arm of a chromosome 6. Consequently, the short arm of chromosome 6 grows shorter in the same proportion (formula 24, t(5p+; 6q–), on the analogy of the human chromosome standardization).—Against all expectation, meiosis in 24, t(5p+;6q–) animals leads to a normal segregation of abnormal chromosomes.—When a heterozygote for translocation is bred with a normal individual or when two heterozygotes are crossed, the offspring is composed of phenotypically normal or abnormal animals, depending on their karyotypes.—The subjects 24, t(5p+; 6q–) and 24, 2(5) –, 2(6) –, 2(5p+) +, 2(6q–)+ have balanced karyotypes; their phenotype is normal. On the other hand, the unbalanced types are lethal or semi-lethal.— The 24, 6–, (6q–)+ and 24, 5–, 2(6) –, 5p+, 2(6q–)+ embryos show a strictly identical syndrome. They die soon after the hatching stage without having been able to eat. The branchial outlines are almost inexistant, the eyes are poorly-formed and the mouth stays wide-open.—The two formulas 24, 5-, (5p+)+ and 24, 2(5) –, 6 –, 2(5p+)+, (6q–)+ produce the same phenotypic aberrations as well. In this case, malformations in older embryos and young larvae are discrete and transient. They are localized at the eye and branchial levels. It is difficult to rear these animals until adulthood. Those that survive, have a disproportionate body and malformations of the vertebral skeleton.—The two formulas 24, 2(6) –, 2(6q–)+ and 24, 2(5) –, 2(5p+) + are so unbalanced that the embryos do not survive beyond the gastrula stage.—The study of the meiotic slides of male heterozygotes bring a cytologie confirmation to the results obtained from the study of the phenotypes and karyotypes established on the offspring. The first meiotic division shows 10 bivalents and one quadrivalent, whereas the study of the karyotypes from the metaphases of the second meiotic division prooves that only four types of different gametes can be formed.—The 6q– chromosome is easily recognizable under direct microscopic study. This translocation constitutes a nuclear marker which can be easily used because the homozygotes for the aberration grow normally and show a normal meiosis.


Cet article recouvre en partie le travail d'une thèse de Doctorat d'Etat de Sciences naturelles qui sera soutenue dans le courant de l'année 1971.  相似文献   

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Lorsqu’un animal meurt, son cadavre forme un écosystème local instable et éphémère où différentes communautés d’insectes nécrophages vont se nourrir. Cette étude a pour but de caractériser les relations entre deux familles fréquentes en contextes médico-légal : les Diptères Calliphoridae et les Coléoptères Dermestidae. Des expériences de choix binaire (olfactomètres en T) et de prédation des Dermestes sur les larves de Diptères ont constitué le 1er axe de notre étude. Il en ressort que l’espèce D. maculatus (adultes et larves) n’exerce qu’une très faible prédation sur les larves de L. sericata. En absence de nourriture, les Dermestes sont néanmoins capables de prédater les pupes de L. sericata, et donc de faire disparaitre ces traces particulièrement importantes en entomologie médico-légale et en archéo-entomologie. Le second axe s’est focalisé sur les relations de compétition et d’agrégation entre D. maculatus et D. haemorrhoidalis. Les résultats obtenus n’ont pas mis en évidence de mécanismes de compétition ou d’exclusion entre ces deux espèces pourtant amenées à fréquenter simultanément le même habitat et à exploiter les mêmes ressources. Placées en condition de choix binaire (2 spots identiques), les 2 espèces s’agrègent ensemble. Mais le développement conjoint de ces 2 espèces sur une seule source de nourriture non limitante entraine une baisse significative du taux de survie chez les deux espèces. Au vu de ces résultats, nous avons conclu à la possibilité d’une coexistence de ces différentes espèces (L. sericata, D. maculatus et D. haemorrhoidalis) sur un cadavre.  相似文献   

6.
La prise en charge par le biologiste de certaines analyses délocalisées se trouve grandement facilitée par la mise en place d’un système informatique reliant l’analyseur délocalisé et le laboratorie. Elle apporte un niveau de sécurité nécessaire pour la prise de responsabilité du laboratoire dans l’acte de biologie délocalisé. L’architecture réseau de la plupart de h?pitaux permet maintenant de transmettre très facilement et de manière fiable des données entre plusieurs services voire entre établissements. Les analyseurs de gazométrie sanguine permettent cette connexion, de plus en plus d’industriels développent d’autres paramètres en plus des simples gaz du sang comme dernièrement l’urée et la créatinine. Les analyseurs permettant de doser les marqueurs cardiaques, ceux réalisant l’hémostase sont désormais fréquemment connectables. Chaque industriel du diagnostic proposant des analyseurs de glycémie a ou va prochainement commercialiser un modèle connectable. Il en est de même pour les bandelettes urinaires. Il est donc probable, et les biologistes sont les premiers demandeurs, que la connexion informatique d’analyseurs de biologie installés dans les unités de soins, soit un pré-requis pour la gestion des analyses délocalisées par le biologiste, et sa prise de responsabilité dans les résultats biologiques issus de ces analyseurs.  相似文献   

7.
This case report exemplifies the role of FDG (18F) PET/CT in case of scattered multiple pulmonary nodules to assist the aetiologic diagnosis and guide the surgical biopsy evidencing a necrotising sarcoid granulomatosis while CT guided biopsy is non-contributive.  相似文献   

8.
《L'Anthropologie》2023,127(2):103136
Between ≈13,000 and 7000 BP, the territory of southern Brazil was occupied in a stable and diverse manner, with the main anthropic trace being in lithic material. Archaeological research has provided more consistent evidence of occupation in different environments and associated with different stratigraphic formation processes since the Late Pleistocene. Therefore, this paper proposes to analyse the history of the earliest evidence of pre-colonial occupation in southern Brazil from a geoarchaeological point of view, focusing on stratigraphic and chronological data and the process of formation of archaeological layers. Thirty-three stratigraphic sections were analysed from 31 archaeological sites distributed along the Paraná, Uruguay and Atlantic basins. Evidence of archaeological levels was found in different geomorphological contexts: plateau, slopes, valley bottom, alluvial plains and rockshelters. The results indicate that the oldest archaeological levels in the region were formed in the Late Pleistocene, associated with periods of fluvial incision that signal important changes in the southern river systems, characterized by the formation of alluvial and colluvial-alluvial terraces in the valley bottoms. This is followed in the Lower Holocene by widespread colluvial processes in the incised valleys, alluvium in the middle river courses and anthropogenic deposits in the rockshelters that formed the main ancient levels. In the early Middle Holocene, sedimentary deposits containing archaeological material decrease significantly, marking regional changes in lithic industries. The data indicate that there appears to be a threshold between deposition and archaeology in the Early Holocene, characterized by high stratigraphic resolution, where stratigraphic sequences show greater thickness and density of archaeological levels. Finally, the diversity of inter-regional lithic assemblages is clearly highlighted, marked by the predominance of industries on pebbles and blocks, the debitage of flakes and blades as a support for various tools in the interior basins and the shaping of small projectile points on the Atlantic slope.  相似文献   

9.
A Masse  P Turgeon  N Gay  G Verschelden 《CMAJ》1988,138(10):921-924
To compare the effectiveness of three doses and of a single dose of cefoxitin, a second-generation cephalosporin, in preventing infection after nonelective cesarean section, we carried out a prospective study in 255 women who underwent the procedure between March 1983 and February 1985. The rate of postoperative infection was 7% in the group that received three doses and 8% in the one-dose group. The sensitivity and specificity of perioperative cultures were low. The rate of asymptomatic bacteriuria was high, at 20%, but few symptomatic urinary tract infections were found. Routine antibiotic prophylaxis with a single dose is suggested for all nonelective cesarean sections.  相似文献   

10.
A sample of 12Mus (Leggada) triton Th. from the region of Bukavu (Democratic Republic of Congo) contains 5 ♂♂ and 7 ♀♀. 2N=32. All the autosomes are acrocentric. The sex-chromosomes of the ♂ are of the typeX—Y, theX beeing a big submetacentric (I.C.=0,4). Three ♀♀ possess two metacentricX, as expected. By four ♀♀, there is only one typicalX whose partner is acrocentric and as long as the long arm of a normalX. ThisX must have been arisen through the deletion of the short arm and is calledX ddc. The statistical analysis of the sample is compatible with this pattern:
$$\begin{array}{*{20}c} { \circ \circ } \\ { + + } \\ \end{array} \begin{array}{*{20}c} {X---X = 4/9} \\ {X---X_{dc} = 4/9} \\ {X_{dc} ---X_{dc} = 1/9} \\ \end{array} \begin{array}{*{20}c} { \nearrow \nearrow } \\ { \circ \circ } \\ \end{array} \begin{array}{*{20}c} {X---Y = 2/3} \\ {X_{dc} ---Y = 1/3} \\ \end{array} $$  相似文献   

11.
Yves Ferroul 《Andrologie》2005,15(1):62-70
The striking feature of the history of sexual desire is the contrast between the omnipresence of sexual desire in human societies, regardless of the period considered, and the negative representation constantly and systematically given to this desire by philosophers and religious leaders. Sexual desire was automatically rejected by those who were disgusted by the animal side of man. The Stoics of the first century A.D., rapidly followed by theologians of the young Christian religion, were convinced that animals only act to satisfy their physical needs, but that moral man had to distinguish himself from the animals by refusing to act simply for pleasure. For Cicero and Seneca “seeking an act because of the pleasure it procures is an abuse”. They applied this principle to food as well as bodily care: unthinking animals live to eat, while moral humans eat to live; food and maintenance of the body ensure health but do not provide pleasure. Similarly, sexuality is only justified for reproductive purposes. However, as already observed by Saint Augustine, this is not the way in which human beings act, and this Church Father had to admit that he had never met a husband able to claim that he “only had sexual intercourse in the hope of fathering”. Other thinkers were more moderate and distinguished acceptable desire, kept under the control of reason and leading to positive action from degrading, irrational desire ending in passion (always considered to be unreasonable). Only the second form of desire must be avoided; the first leads to happiness and fulfilment and remains the force that usually drives human action. Christian thinkers of the Middle Ages, attentive to the real life of believers, finally accepted that the human characteristic of memory is one of the most beautiful gifts of God, allowing man to remember past pleasures and therefore to rightfully experience the desire to repeat these pleasures: coitus without a reproductive purpose therefore appears to be part of the divine plan. A theologian, in contrast with dominant religious opinion, even declared “if someone eats a pear or a beautiful fruit only for the pleasure, it is not a sin. The same applies when a man has intercourse with his wife only for the pleasure”. However, far from theoretical discussions, individuals declared their deep attachment to desire, during the Renaissance, at the court of the Sun King, in salons of the Enlightenment or even, in contrast with a widely held belief, in the new industrial world of the 19th century. Today, while religious authorities still generally have a Stoic view of pleasure and desire, modern thought has advanced in its understanding of the place of desire in human experience and recognizes it an essential driving role responsible for fulfilment and a powerful stimulus for all forms of creativity. The history of sexual desire therefore corresponds to the steps of enrichment of basic animal instinct by the human species and the individual and social forms of expression of this desire.  相似文献   

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《Médecine Nucléaire》2017,41(4):280-290
The retroperitoneal masses are various and heterogeneous and include tumors from different organs (kidneys), the primary retroperitoneal tumors and metastasis. The primary retroperitoneal tumors are rare, frequently malignant with a delayed diagnosis. More than half of them are sarcoma. Rarity and heterogeneity of retroperitoneal tumors explain the difficulties of diagnostic. The goal of this article is to review the imaging characteristics of CT scan and RMN of retroperitoneal mass and to clarify the diagnosis. The management of sarcoma requires an expert multidisciplinary team (pathologist, radiologist, surgeon, oncologist) and pathology analysis by retroperitoneal transcutaneous biopsy.  相似文献   

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90% of spinal cord injury patients cannot have an ejaculation during either sexual intercourse or masturbation From 1987 to 1993: 52 patients were treated by vibratory stimulation, 21 by electrostimulation, 4 by Physostigmine. Overall success rate during vibratory stimulation is of 65% and 83% if one considers only patients with a sublesional syndrome below T10. We obtained 15 successes among 21 tetraplegic patients and 19 successes among 20 paraplegic patients. Ejaculation was always obtained within three minutes. We did not obtain any success in paraplegic patients group whose lesional level was T12, L1, L2. After having trained the couple for the technique, we realised on two occasions, during ovulation (twelfth to sixteenth day before next menstruation date), intravaginal autoinseminations with a syringe for a minimal duration of one year, necessary time to improve semen quality before treating procreation as a medical issue. Among these 52 patients treated by vibratory stimulation, only 12 couples came to take our advice in order to procreate. Out of the 12 followed up couples, we obtained 3 births and 1 current pregnancy. 16 patients out of the 21 treated by electrostimulation have an ejaculation. Out of the 30 realised ejaculations, 11 were retrograde. Semen volume and quality are much lower to what we obtained by vibratory stimulation. Actually, this technique has not allowed a pregnancy. 2 out of the 4 patients having had a treatment by Physostigmine had an ejaculation. Ejaculation by vibratory stimulation is the easiest technique and it must be proposed as a first purpose. In a second time, proposed intrarectal electrostimulation allows nearly always to get semen if a sufficient number of sympathetic thoracolumbar fibres are preserved.  相似文献   

16.
Culicoides biting midges (Diptera: Ceratopogonidae) serve as biological vectors for several pathogens, including the Bluetongue virus and the recently described Schmallenberg virus in northern Europe. These diseases have caused considerable direct and indirect economic losses to the sheep and cattle industries. This study undertaken between August and December 2007 on a sheep farm in the Namur province (Belgium) aims to evaluate Culicoides populations present inside a partially opened sheepfold and in a nearby sheep meadow, using light traps. The comparative analysis of insects trapped at 18 dates at regular intervals showed that Culicoides were most abundant inside this livestock building (17,450 midges) than in surrounding meadow (1,121 midges); this meadow had however a greater species diversity. The two species C. obsoletus and C. scoticus constituting the Obsoletus complex predominated for all trappings and females were much more numerous than males. Important capture of engorged females of the Obsoletus complex inside the sheepfold seems to reflect the possibility of an opportunistic endophagous behavior. Maintaining sheep inside livestock buildings in order to reduce the risk of Culicoides bites – and thus of pathogens transmission – however requires to limit biting midge populations which are likely to enter or to develop inside these buildings. Implementation of effective sanitation and hygiene measures against midges present inside farms, as well as establishing of measures to protect livestock against intrusion and improvement of “midge-proofing” of animal housing are therefore highly recommended.  相似文献   

17.
B. Cellot  M. Bournaud 《Hydrobiologia》1986,135(3):223-232
Artificial substrates suspended in the water column and benthic dredging were employed to study the drift of macrofauna and the macrobenthic populations respectively, in a cross section of the Rhône River upstream of Lyon, France. The samples were collected in autumn 1979: first in September under a low flow egime around 400 m3·s–1, then in October during a discharge increase up to 630 m3·s–1.The first factor of correspondence analysis showed a clear cleavage between the two periods, especially for drift communities. The differences are most important in the centre of the stream channel. In October, the water column was invaded by unusual and abundant fauna. This dynamics is due to the increase in number of Crustacea (Gammarus fossarum, Asellus aquaticus), the decrease of some insect larvae (Leuctra fusca, Simuliidae, Baetis fuscatus, stages 1 and 2 of Hydropsyche) and the appearance of typical wetland taxa (some limnophilous Coleoptera and Trichoptera). For some other dominant invertebrates, a modification may occur only in their distribution (stages 3 to 5 of Hydropsyche, Heptagenia sulphurea) while the distribution of Psychomyia pusilla remains the same.These results are discussed with respect to the effects of species biology and the unusual consequences caused by a minor increase in discharge.
Structure et fonctionnement des écosystèmes du Haut Rhône français n° 46.  相似文献   

18.
《IRBM》2009,30(4):171-173
Applying ultrasound on drug-loaded sonosensitive liposomes offers new possibilities for treating cancer. In vitro experiments were performed in the present study to define an index of inertial cavitation which could be used to monitor the delivery of drugs. This index could also be used to assess the sonosensitivity of new formulations of liposomes. Experiments were then carried out in rats bearing subcutaneous abdominal tumors. Based on pharmacokinetic and biodistribution studies, a period of 48 hours was chosen between the injection of the liposomes and the exposure to ultrasound. At the injected doses, liposomes slowed down significantly the tumor development. Ultrasound combined with liposomes seemed to contribute to the tumor control. However, the important efficacy of liposomes alone and the eventual weak interactions with ultrasound prevent to guarantee that the effect of ultrasound is significant.  相似文献   

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