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1.
The majority of research program on new radiopharmaceutics turn to tracers used for positron emission tomography (PET). Only a few teams work on new non fluorine labeled tracers. However, the coming of SPECT/CT gamma cameras, the arrival of semi-conductors gamma cameras should boost the development of non-PET tracers. We exhibit in this article the experience acquired by our laboratory in the conception and design of two new non fluorine labelled compounds. The 99mTc-NTP 15-5 which binds to proteoglycans could be used for the diagnosis and staging of osteoarthritis and chondrosarcoma. The iodobenzamides, specific to the melanin, are nowadays compared to 18F-fluorodeoxyglucose in a phase III clinical trial for the diagnosis and detection of melanoma metastasis. Our last development focus on BZA heteroaromatic analogues usable for melanoma treatment.  相似文献   

2.
Résumé L'étude des protéines des granules dePieris brassicae L. et des polyèdres nucléaires deBombyx mori L. par les techniques de filtration sur gel, d'électrophorèse et d'immunodiffusion révèle de nombreuses ressemblances. La comparaison des protéines des corps d'inclusion engendrés par lesBaculovirus des Lépidoptères contribue à montrer l'homogénéité de ce groupe.
Summary It is generally admitted that the viruses of nuclear polyhedroses and granuloses of Lepidoptera form two distinct groups serologically. A comparative study of proteins of nuclear polyhedral bodies ofBombyx mori and of granules ofPieris brassicae was carried by using techniques of gel filtration, electrophoresis and immunodiffusion. The characteristics of proteins of granules studied by gel chromatography and electrophoresis are closely related to those of proteins of polyhedral bodies. In immunodiffusion, the extraction of proteins of polyhedral inclusion bodies by the carbonate reveals a common antigen (C antigen) which is recognized by homologue serums and anti-protein heterologue serums of inclusion bodies of seven otherBaculovirus. The extraction by the thioglycolate reveals, in addition to C antigens, specific antigens: T antigen for the granulosis ofPieris brassicae and B antigens for the nuclear polyhedrosis ofBombyx mori. The comparison of proteins of inclusion bodies generated by granulosis and nuclear polyhedrosis viruses contributes to show the homogeneity of the LepidopterBaculovirus group.


Avec la collaboration technique de LilianeCroizier.  相似文献   

3.
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   

4.
Summary The extracellular space of tentacles of Drosera capensis L. is divided into two compartments by cuticular material between cells of an endodermoid layer and by the nonporous cuticle of the stalk and neck. The distal compartment includes the mucilaginous secretion as well as the free space of the secretory cap, since the cuticle covering the cap is perforated by numerous 0.05–0.3 m pores. The proximal compartment includes xylem and the intercellular space of the stalk. The existence of the endodermoid partition is consistent with the observation that action potentials recorded extracellularly from the head may be positive-going while those recorded extracellularly from the stalk are negative-going. The partitioning is also consistent with the hypothesis previously proposed to explain why the amplitude of action potentials recorded from the mucilage varies as a function of the amplitude of the receptor potential.The living cells are united by plasmodesmata. Unusually abundant plasmodesmata were observed in the walls between endodermoid cells and neck cells, between neck cells and the next row of outer stalk cells, in the end walls connecting the outer stalk cells, and the end walls connecting the inner stalk cells: these strategically located plasmodesmata presumably permit the electrotonic spread of receptor potentials and action potentials between cells.  相似文献   

5.
Summary Barley chloroplasts (Hordeum vulgare L.) have been isolated in aqueous medium by previously described techniques which preserve the outer plastid membrane in numerous chloroplasts. Thus intact chloroplasts are concentrated in Class I fraction and non intact in Class II fraction. A third type, broken Class I, is obtained by the action of a very dilute buffer solution.The observation of freeze-etched preparations has shown that the main distinctive character between the two classes is not so much the presence or the absence of the outer plastid membrane, as it was assumed, as the state of the thylakoids. In Class I chloroplasts grana are shrunken, in those of Class II, grana are swollen. In both cases the outer membrane may or may not be preserved.The breakage of chloroplasts resulting from treatment with osmotic shocks is due to the dilatation of the extra-lamellar matrix. The swelling of intra-thylakoidal volumes resulting from such a treatment is much less important.It is shown that Class I chloroplasts have a very low NADP reductase activity which is strongly increased after the chloroplasts are broken by osmotic shocks. Such a treatment is without any effect on Class II chloroplasts, which always exhibit a low NADP reductase activity.The situation is rather different in regard to photophosphorylation. It is also lower in Class II than in Class I, but after breakage by osmotic shocks the increase of this activity is weak, and much less significant than the increase observed in NADP reduction. The compression and cohesion of the thylakoids is not required for high photophosphorylation activity with artificial electron acceptors such as PMS. In this case cyclic photophosphorylation is higher in Class II than in Class I.
Abbreviations ADP, ATP adénosine di et triphosphate - EDTA éthylène diamine trétaacétate - NAD, NADP, NADPH2 nicotinamide adénine dinucléotide, d° phosphate (formes oxydée et réduite) - PMS phénazine méthosulfate - Pi phosphate inorganique  相似文献   

6.
7.
Gibberellic acid GA3 (50 ppm) decreases the photosynthetic rate and increases respiration rate of rye leaves (Secale cereale L., cv. Dankowskie Zlote). The effect of GA3 on transpiration rate is not distinctly marked.  相似文献   

8.
Résumé Les sites d'élaboration de l'ACTH, de l'-MSH et de la -MSH ont été recherchés par immunofluorescence à l'aide de sérums préparés contre l'-MSH, la -MSH bovine et la -(1–24) corticotropine synthétiques. L'absence de réaction croisée entre ces différents antigènes conduit à admettre que, dans les espèces testées (bovins, ovins et porcins), les cellules du lobe intermédiaire élaborent simultanément l' et la -MSH, tandis que les cellules corticotropes du lobe antérieur secrètent l'ACTH et la -MSH, l'-MSH étant absente de la pars distalis; la spécificité de la réaction paraît due à l'absence de déterminants anticorps dirigés contre l'heptapeptide commun à ces trois hormones polypeptidiques.
Immunofluorescent localization in adenohypophyseal cells of corticotrophic and - and -Melanotrophic secretions in the cow, the sheep, and the pig
Summary The sites of production of ACTH, -MSH, and -MSH were studied by immunofluorescence using antisera prepared against synthetic -MSH, bovine -MSH and -(1–24) corticotropin. The absence of cross-reactions between the different antigens lead us to conclude that, in bovine, ovine and porcine species, the cells of the intermediate lobe produce - and -MSH simultaneously, while the corticotrophic cells of the anterior lobe secrete ACTH and -MSH (-MSH is absent in the anterior lobe). It seemed that the specificity of the secretion is due to the absence of antibody determinants against the hepta-peptide, common to the three polypeptide hormones.
1 Abréviations utilisées: MSH: Melanocytes Stimulating Hormone; ACTH: Adrenocorticotrophic Hormone; PAS: Periodic Acid-Schiff (reaction d'Hotchkiss Mac-Manus); Ac.: Anticorps; Ag. Antigène; C: Complément.  相似文献   

9.
Cells mechanically isolated from homogenized leaves ofC. sepium dividein vitro. The rate of cell division is strongly influenced by temperature with the optimum between 31 and 34 °C. The rate of cell division increases proportionally with a rise in temperature up to 31 °C and is accompanied by a reduction in the length of the preparatory phase of the division. A supraoptimal temperature (40 °C) inhibits or stops the cell division which can be restored provided that the cells are transferred to 31 °C. If the preparatory phase to the commencement of cell division is accomplished at 17 °C the cells then exposed to 31 °C divide more rapidly than if they are exposed directly to 31 °C.  相似文献   

10.
11.
Résumé Une faible dose de rayonnement gamma appliquée à des larves de Locusta migratoria provoque des altérations de la spermiogenèse et entraine la stérilité des mâles. Ces résultats sont comparables à ceux obtenus après implantation des corps allates.Au niveau des organites cellulaires, les altérations morphologiques des spermatides sont semblables dans les deux cas: vacuolisation des mitochondries et transformation du Nebenkern, pycnoses nucléaires, multiplication centriolaire, invagination de la membrane plasmique. Certaines de ces altérations se manifestent tardivement, au moment de la fixation des spermatides sur les cellules pariétales. Celles-ci n'élaborent pas les matériaux de la coiffe des spermatodesmes: leur fonction physiologique est donc également perturbée.Le rapport entre cette altération physiologique et l'évolution anormale des spermatides est envisagé. Le mode d'action de l'hormone juvénile sur la gonade est également discuté.
Alterations in spermiogenesis of Locusta migratoria migratorioïdes after corpora allata implantation and after irradiation
Summary Low doses of gamma-rays, given to larvae of Locusta migratoria, lead to alteration of spermiogenesis and male sterility. These results are similar to those which follow corpora allata implantation.At cellular level, morphological alterations in spermatids are the same in both treatments: mitochondrial vacuolization, nuclear pycnosis, centriole multiplication, plasmic membrane invagination. Some of these alterations reveal themselves late, at the time the spermatids fix on the parietal cells. These don't elaborate the substances of the spermatodesm's cap: their physiological functions are therefore also disturbed.The relationship beetween this physiological disturbance and abnormal evolution of spermatid are considered and the way in which juvenile hormone acts upon gonads is discussed.
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12.
J. Auger 《Andrologie》1996,6(3):320-329
The sperm quality analyzer (SQA) is a device which has been recently proposed to make an objective measurement of human semen quality. It is based on a simple physical method: the measurement of optical density modifications induced by sperm movement. Optical density modification are measured though an electro-optical photoreceptor. Analogical signals produced are transformed in numerical signals and analysed by a microprocessor. The result of the analysis is given in a unique value called «sperm motility index» (SMI). In this study the reproducibility of the results got with the SQA has been measured and the interests of this new diagnostic technique for the andrological laboratory and for human sperm freezing have been evaluated. It can be conclude that SMI measurement is simple, well reproductive and very useful to evaluate the overall quality of a sample. The SMI allows a good prediction of the efficiency of the methods used to select spermatozoa so it can help to choose the best technique, in order to prepare the spermatozoa for a medically assisted procreation. Values of SMI after freezing and thawing of semen samples were also reproducible. They were well correlated to the number of motil sperm per straw as measured by conventional methods, SMI was more objective and accurate. From the value of SMI measured on fresh samples it was possible to predict the freezing tolerance. Therefore measurement of SMI could be very useful to check straws quality and in studies on human semen cryopreservation. Prospective studies are further needed to determine if the SMI could also predict “in vivo” fertility of IVF results and fertilizing ability of frozen thawed sperm.  相似文献   

13.
Résumé Des disques imaginaux de patte, prélevés dans des larves de fin de 3e stade de drosophile, ont été cultivés dans le milieu M de Mandaron, en l'absence d'hormone ou en présence soit d'- soit de -ecdysone. L'incorporation de précurseurs marqués (3H-uridine,3H-leucine ou3H-proline) a été étudiée en fonction du stade de développement des disques.En l'absence d'hormone de mue, l'incorporation d'uridine décroît dès que les disques ont été explantés; l'incorporation de leucine et de proline ne décroît que 6 à 12 heures après l'explantation.- et -ecdysone stimulent l'incorporation des trois précurseurs; toutefois celle-ci varie en fonction du développement morphologique du disque.Les maxima et les minima d'incorporation d'uridine précèdent dans le temps ceux de la leucine et de la proline.Les maxima d'incorporation peuvent être mis en rapport avec des évènements morphologiques marquants du développement: évagination, sécrétion des cuticules nymphale et maginale.Il n'y a pas de différences significatives d'incorporation d'uridine en présence d'-ecdysone ou de -ecdysone; en revanche les maxima d'incorporation de leucine et de proline sont plus élevés en présence d'-ecdysone que de -ecdysone.Ces résultats montrent que l'-ecdysone—et à un degré moindre la -ecdysone—peuvent induire les synthèses de macromolécules nécessaires au développement des appendices in vitro.
RNA and protein synthesis inDrosophila leg discs cultured in vitro
Summary Imaginal leg discs from late third instarDrosophila larvae were cultured in Mandaron's medium without hormone or with -ecdysone or -ecdysone. Incorporation of labelled precursors (tritiated uridine, tritiated leucine or tritiated proline) was studied as a function of the stage of in vitro disc development.In the absence of moulting hormone, uridine incorporation decreased as soon as the discs were explanted; leucine and proline incorporation however began to decrease only after 6 to 12 h.- and -ecdysone stimulated the incorporation of all three precursors; however the rate of the incorporation varied as a function of the morphological disc development.The maxima and minima of uridine incorporation preceeded in time those of proline and leucine incorporation.The peaks of incorporation were coincident with salient morphological events of development: evagination, secretion of pupal and imaginal cuticles.There were no significant differences in uridine incorporation in the presence of -ecdysone or -ecdysone. Leucine and proline incorporation maxima however were significantly higher in the presence of -ecdysone than of -ecdysone.The results show that -ecdysone—and to a lesser extent also -ecdysone—can induce the macromolecular syntheses required for the development of the appendage in vitro.


Ce travail a été réalisé avec l'aide du CNRS (Action thématique programmée «Différenciation cellulaire», contrat no A 6554324)

Ce mémoire représente une partie de la thèse qui sera soutenue par l'auteur devant l'Université Scientifique et Médicale de Grenoble  相似文献   

14.
Summary The pineal organ of Anguis fragilis contains two essential cell types: pinealocytes and interstitial cells. The scarce outer segments are of different appearance; they show cyclic degenerative changes. Only one intraepithelial ganglion cell has been identified in the material of this study. Although an intracommissural pineal nerve is present, the absence of synaptic junctions of pinealocytes with ganglion cells indicates a loss of photosensory function. Three kinds of vesicles (also dense-core vesicles) originating from Golgi complex are described in the pinealocytes. These secretory vesicles show a vascular polarity. The pinealocyte processes extend to the basement membrane. Secretory material is released into the peripineal space. Efferent sympathetic nerve fibers are described near the pineal epithelium. The nerve endings of these fibers contain three types of vesicles. It is suggested that the pineal organ of Anguis fragilis has a well established secretory function.
Zusammenfassung Die Epiphysis cerebri von Anguis fragilis enthält zwei wesentliche Zelltypen: Pinealocyten und Zwischenzellen. Die Außenglieder, die nur selten vorkommen, sind verschiedenartig gestaltet und erleiden einen zyklischen Degenerationsprozeß. Im Pinealepithel ließ sich nur eine einzige Ganglienzelle mit Sicherheit nachweisen. Obwohl eine intracommissurale Nervenbahn vorhanden ist, spricht das Fehlen von Synapsen zwischen Pinealocyten und Ganglienzellen für einen Schwund der Lichtsinnesfunktion. In den Pinealocyten werden drei aus dem Golgiapparat stammende Bläschenarten, darunter auch solche mit einem elektronendichtem Inhalt (Granula), beschrieben. Diese Sekretbläschen sind polar auf die Blutgefäße ausgerichtet. Fortsätze der Pinealocyten stehen mit der Basallamina in Verbindung; allem Anschein nach werden hier Substanzen in den periepiphysären Raum abgegeben. Efferente sympathische Nervenfasern sind in der Nähe des Epiphysenepithels zu beobachten. Die Endigungen dieser Fasern enthalten drei verschiedene Bläschentypen. Die Epiphyse der Blindschleiche scheint eine sekretorische Funktion zu haben.
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15.
Résumé Le programme biogaz au Burundi a démarré par la création d'un Département chargé de la mise au point de stratégies de vulgarisation de nouvelles sources d'énergie. Au sein de ce Département on a établi les constats suivants: (1) la nécessité de former des cadres et d'établir un inventaire de la biomasse biodégradable au Burundi; (2) un problème de collecte des déchets et de distribution du gaz et des effluents dû à l'habitat dispersé; (3) l'existence de collectivités (écoles, hôpitaux, casernes); et (4) l'évacuation dans le lac Tanganyka des déchets des usines agro-alimentaires. En conséquence le Burundi a fait appel à trois formes de coopération. Un financement de l'Administration Belge de la Coopération au Développement a permis l'éstablissement d'un centre de démonstration et d'un laboratoire responsables de recherches, cours de formation, démonstration et suivis scientifiques et techniques. Un financement du Gouvernement Burundais permet à trois experts chinois la réalisation de digesteurs pilotes à raison de cinq à six par province. Un financement de la GTZ permet la diffusion de la technologie par le biais de la mise en place d'une structure (bureaux régionaux, formation de techniciens maçons et de multiplicateurs potentiels) et la construction d'installations.
Summary The Burundi biogas programme started with the setting up of a new Department with the overall responsibility for the popularization of new sources of energy. The biogas programme started because : (1) it was felt necessary to train staff and to establish an inventory of the biodegradable biomass in Burundi; (2) a largely scattered habitat complicated both the collection of domestic waste and the distribution of gas; (3) there existed large communities like schools, hospitals, etc.; and (4) the fact that Lake Tanganyka was more and more used as a dumping area for the wastes of the agro-industrial industry. Thus three cooperation programmes were started. From Belgium a funding by BADC allowed setting up of a demonstration centre and laboratory to promote research on biomethanation, to train personnel and permit scientific and technical follow-up of biomethanation projects. Three Chinese experts were recruited to help realize pilot digesters in all the provinces. And finally a programme funded by West Germany realized the dissemination of the technology through the country with the training of peasants via local training centres.

Resumen El programa de biogas de Burundi empezó con la creación de un nuevo departamento con la misión de popularizar nuevas fuentes de energía. El programa de biogas empezó porque (1) se creyó necesaria la formación de personal y el establecimiento de un inventario de la biomasa biodegradable en Burundi, (2) el hábitat muy desperdigado complica tanto la recolección de basuras domésticas como la distribución de gas, (3) existen comunidades numerosas como escuelas, hospitales etc. y (4) el lago Tanganika se estaba utilizando cada vez más como un basurero para los desechos de la industria agro-industrial. Así pues se iniciaron tres programas de cooperación: Bélgica mediante la financiación del BADC permitió la creación de un centro de demostración y de un laboratorio para promocionar la investigación en biometanación, formar al personal y permitir un seguimiento científico y técnico de los proyectos de biometanación. Se ha obtenido la colaboración de tres expertos chinos para ayundar a la realización de digestores piloto en todas las provincias. Y finalmente un programa financiado por Alemania Occidental se encarga de la distridución de la tecnología por todo el país formando campesinos a través de centros de formación locales.
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16.
17.
Through paleogenetic studies we have characterised the sampling of a sepulchral cave named Elzarreko Karbia, in the Basque Country (France). Four people had been buried in this cave in the Ancient Bronze Age, three men, including an adolescent, and a woman, dating from 3 700 BP. In addition to a confirmation of the anatomical sex determination through amelogenin first intron amplification, we obtained a mitochondrial second hypervariable region (HVR II) sequence for each individual, and thus, we excluded maternal relationship between some of the skeletons.  相似文献   

18.
Glucose derivatives of hydroxycinnamic acids have been identified in tomato fruits either as esters or glucosides, the latter always being the most abundant and increasing during growth and at the time of ripening. These compounds can be synthesized in vitro by a fruit glucosyltransferase from free hydroxycinnamic acids and UDPG; glucosides are always formed in higher amounts than esters.  相似文献   

19.
20.
《Geobios》1988,21(5):567-609
The genus Pachyerymnoceras, with four new species,is described for the first time in Western Algeria. The genus first appears in the Middle Callovia (Coronatum Zone) as in Saudi Arabia. It is represented in the Saida region by uncommon P. praecox nov. sp. followed during the Upper Callovian (Athleta Zone) by specimens belonging to P. flamandi sp. nov., P. kmerense nov. sp. and P. saidense nov. sp. Every species is represented by a dimorphic pair.Pachyceratidae are put into Perisphinctaceae. If Pachyerymnoceras arises from Erymnoceras, a genus suddenly appearing during the Middle Callovian on northern and southern Tethyan borders, the origin of Erymnoceras is still unknown. Three phylogenetic hypothesis are considered here. Erymnoceras may have evolved during Lower Callovian: 1) from serpenticonic Tethyan Pseudoperisphinctinae like Choffatia (Subgrossouvria); 2) from Tulitids via ellipticoncic Bullatimorphites (Kheraiceras); 3) through a double lineage arisen in Subboreal and Tethyan platyconic Proplanulitids.Pachyceratids have a wide paleobiogeographic distribution in NW Europe and on the Tethyan margins. The genus Pachyerymnoceras evolves in Ethiopian Province of the Tethyan Realm. Some species migrate into Indo-Malagasian Province and others, through the south Tethyan border came to Europe were they are found restricted to Upper Callovian (Athleta and Lamberti Zones). Therefore this migration has a duration of two or even three zones.  相似文献   

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