首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The speciesRoemeria bohemica Po?ta has been revised on the basis of its original material and of topotypical specimens: its characters are in general consistent with those ofCalamopora infundibulifera Goldfuss 1829, type species of the genusRoemeria Milne-Edwards & Haime 1851.Roemeria bohemica is characterized by the numerous complex tabulae and the strong development of septal spines. These characters are considered by us of only specific importance and the genusRoemeripora Kraicz 1934, based onR. bohemica, is thus considered as a junior synonym ofRoemeria. An exhaustive list of the Devonian species attributed toRoemeria or toRoemeripora is given.  相似文献   

2.
Résumé Les fibrilles constitutives du phragmoplaste sont de nature protéique. L'action du-mercaptoéthanol permet de conclure que ces protéines sont liées par des ponts S-S. En présence d'urée, la structure du phragmoplaste est détruite, ce qui indique l'existence de liaisons hydrogènes.
Zusammenfassung Unsere Arbeit führt zu folgenden Resultaten: 1. Die im Phragmoplast befindliche Faserstruktur besitzt einen Eiweißstoffcharakter. 2. Der Effekt des-Merkaptoäthanols gestattet die Annahme, daß die Proteine mit S-S-Brücken verbunden sind. 3. Bei Anwesenheit von Harnstoff wird die Phragmoplaststruktur zerstört, was für das Vorhandensein von H-Brücken spricht.


Boursière de la Fondation Rockefeller  相似文献   

3.
《Médecine Nucléaire》2017,41(2):83-92
IntroductionRadionuclide ventriculography provides a reproducible measurement of the left ventricular fraction ejection (LVEF) but with a significant body radiation (effective dose of 5,9 mSv for the injection of 850 Mbq of 99mTc). The highly sensitive semi-conductor (CZT) cameras could allow decreasing the injected activity by a factor 3, similarly to that of myocardial perfusion imaging. Our study was aimed to determine whether the LVEF measurement provided by radionuclide ventriculography on the CZT D-SPECT camera is impacted by a 70% reduction in recorded counts.Materials and methodsAfter the in vivo labeling of red blood cells with 850 MBq of 99mTc, 49 patients completed a conventional 2D recording (Conv-2D) on Anger camera followed by a 3D recording on the D-SPECT camera (3D-100%). The CZT recordings of all projections were subsequently shortened to 30% of their initial durations (3D-30%) in order to assess the LVEF measured with a 70% reduction in recorded counts.ResultsMean LVEF values were 62.7 ± 11.1% on Conv-2D and higher on both 3D-100% (66.8 ± 14.8%, P < 0.001) and 3D-30% (66.3 ± 15.7%, P < 0.001). The correlation coefficients with the LVEF determined with the reference Conv-2D method were equivalents for 3D-100% (r2 = 0.73) and 3D-30% (r2 = 0.70) and with a similar level of overestimation for the highest LEVF values.ConclusionA 70% reduction in recorded counts does not significantly impact the LVEF measured with radionuclide ventriculography on the CZT D-SPECT camera. These values are coherent with those obtained with the reference 2D method but with a clear overestimation for the highest LVEF values.  相似文献   

4.
La biologie délocalisée prend une importance croissante dans le fonctionnement des services traitant les urgences à l’h?pital. Elle devrait représenter une réele évolution pour la prise en charge du patient tout en améliorant l’organisation interne des unités de soins. Le biologiste occupe un r?le clé pour mener un tel projet et la mise en place d’un système d’assurance qualité adapté à cette pratique est indispensable.  相似文献   

5.
6.
《Geobios》1988,21(3):359-365
The study of the phosphate-bearing series of Kpogame-Hahotoe permits to identify four successive fossiliferous levels which yielded a rich Middle Eocene selachian fauna. The field observations and the sequence of faunal associations lead to revise the interpretation and age of the phosphate deposit.  相似文献   

7.
The study of Chonetacean Brachiopods from Cantabrian Mountains allows to recognize several new taxa restricted to this area. A new genus and seven species of which six are new, are described in this paper; their vertical distribution is from Gedinnian to Upper Givetian: Chonetes bediae n. sp., Chonetes? kerforneiRenaud, 1942, Plebejochonetes coliensis n. sp., Plebejochonetes moniellensis n. sp., Luanquella cantabriensis n. g., n. sp., Plicanoplia sotoi n. sp. et Longispina truyolsi. n. sp. The species kerfornei, from the Middle Devonian of Armorican Massif is cited here for the first time from Spain.  相似文献   

8.
《Médecine Nucléaire》2014,38(5):293-298
Positron emission tomography (PET) with fluorodeoxyglucose (FDG) is a nuclear imaging method whose interest in oncology has only grown over the past fifteen years. This article summarizes the results in monitoring and therapeutic evaluation of breast cancer. For the search of locoregional or distant recurrence, the performance of FDG-PET are very interesting. The impact of FDG-PET on the therapeutic management is undeniable. For therapeutic evaluation, this imaging is useful to evaluate the neoadjuvant chemotherapy and hormonotherapy efficacy. FDG-PET is indicated in cases of suspected recurrence (clinical, biological or imaging suspicious). It is the most sensitive exam for the detection of bone or visceral metastases. It allows the re-staging during a relapse proved whether local or remote, and can change the therapeutic management.  相似文献   

9.
10.
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.
  相似文献   

11.
Simon Tillier 《Geobios》1975,8(1):75-78
This miocene organism was described as an Alga (Lithophyllym vinassaiPATRINI, 1932 = Neosolenopora patriniiMASTRORILLI, 1955) and as a Bryozoan (Reptomulticava parviporosaCANU et LECOINTRE, 1934). This paper shows several salient features of Cyclostomatous Bryozoans (morphology, microstructure, zoarial brood chamber). The arguments for the classing of this organism among Algae are simultaneously refuted (pseudo-differentiation of the thallus, conceptacles).  相似文献   

12.
13.
《L'Anthropologie》2018,122(4):654-678
Abrigo de la Quebrada offers an exceptional sequence with nine occupation levels which seven belongs to Middle Paleolithic. The division between levels II to V and VII to IX by a sterile level VI allow us to study diachronic changes on raw materials and knapping systems. This data is compared with other contemporary sites to evaluate technological trends and the raw material availability in the central region of Mediterranean area.  相似文献   

14.
This work describes new species of ostracodes collected in the Middle and Upper Bathonian outcrops of the Grands-Causses, Southern France: Kirtonella vignesensis n. sp., Marslatourella bathonica n. sp., Micropneumatocythere montmejeaneansis n. sp., Praeschuleridea alzonensis n. sp., and illustrates the predominating species in the assemblages: Limnocythere larzacensis, Theriosynoecum aveyronensis et Fastigatocythere juglandiformis.Ostracode assemblages are characteristic of lacustrine to polyhaline and inner marine environments, and they vary according to changes in salinity, oxygen and trophic level.  相似文献   

15.
Annick Isaia 《Planta》1971,96(2):175-182
Summary The activities of (±)-abscisic acid and a number of compounds derived from p-coumaric acid and coumarin and their interaction with gibberellic acid in the control of the elongation of the first wheat leaf are examined. (±)-Abscisic acid strongly inhibits leaf growth in the presence as well as in the absence of gibberellic acid, but the inhibition is greater in the presence of gibberellic acid (3 g/l already have an observable effect). Among other compounds, only ferulic acid and coumarin significantly reduce leaf elongation, and they are effective only at high concentrations (1.44 · 10-4 M/l).  相似文献   

16.
In 1979 and 1980, batch culture experiments were conducted to observe the inhibitory effect of copper ion (concentrations of 10, 50, 100, 200 and 400 µg Cu · l–1) on the standing crops and photosynthesis of phytoplankton of the Saguenay River (for 124 hours) and in Chlorella vulgaris (for 8 days). These algal assays were carried out using the surface water of the Saguenay River. In natural populatoins of phytoplankton, it was found that photosynthesis was more sensitive than growth: at the lowest concentrations, such as 10 µg Cu · 1–1, copper seemed to increase the chlorophyll concentrations whereas the rates of primary production show a decrease of 60% with respect to the control. At higher concentrations of copper, the effect is weak in chlorophyll concentrations and more pronounced in the rates of primary production (decrease of 86 to 90%). The pennate diatoms are dominant (in all the samples) and these organisms are known as relatively resistant to copper. In Chlorella vulgaris, it was observed that with 100 µg Cu · 1–1, chlorophyll concentrations and rates of photosynthesis respectively decrease by 63 and 99% with respect to the control. At higher concentrations of copper, a maximum decrease of 70% and 99% respectively for chlorophyll concentrations and rates of primaryproduction are observed.
  相似文献   

17.
《L'Anthropologie》2019,123(1):116-122
Beside the metallic weapon figures, the engravings of the sites of North Akka showed signs of the existence of cattle, mostly oxen cattle. The representation of anthropomorphs is also notable for its evolving aspects towards the schematic style of Libyco-Berber. Regarding wildlife, it is also represented encompassing elephants, rhinoceros, ostriches, antelopes, etc. Nevertheless, the figures of domestic cattle precede those of other subjects. The (peltiform) axes and the dagger, figured in two sites, attest to a mastered knowledge of metallurgy.  相似文献   

18.
Jacques Thierry 《Geobios》1976,9(3):291-331
From Bajocian to lower Kimmeridgian, the subfamilyStephanocerataceae represents a large stock of the ammonite fauna. Though it is tributary of author's stratigraphical correlations and systematical interpretations, its geographical distribution with a drifting continents concept gives many teaching about the study of this superfamily, the continental drift and its consequences. Showing a world wide repartition at its apparition this stock then presents branches; the one (Stephanoceratidae) is not envisaged here; the second (Sphaeroceratidae and Cardioceratidae families) characterises rather the «boreal province; the third (Macrocephalitidae family) is chiefly specific of the «tethysian province. A «north-east pacific province with boreal affinities and a «south-east province with tethysian affinities are delimited. It is probably from its fauna that the tethysian macrocephalitid stock appears; first represented by ammonites specifically north american in middle and upper Bathonian stage, they extend during upper Bathonian and lower Callovian and reach South America and the Tethys. The presence of a narrow sea, on Patagonia, West Antarctica, East Africa, Madagascar and India, joining the Tethys and the south edge of Gondwania, is proved at various times, at Bajocian and Callovian stages.  相似文献   

19.
Despite surgical treatment, cryptorchidism is the most common cause of infertility. Through a literature review, the authors report current data on the influence of age at the time of orchidopexy, testicular size, the position of the testis, and the existence of epididymal anomalies on fertility.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号