4,534 research outputs found
Etude comparative de protocoles de vaccination contre la maladie de Newcastle dans les élevages modernes de poules pondeuses au Sénégal
Plusieurs protocoles de vaccination contre la maladie de Newcastle sont utilisés au Sénégal sur les poulettes futures pondeuses en élevage moderne. Cependant, chaque année, cette virose se manifeste par des mortalités ou des chutes de ponte qui grèvent le budget des exploitants de la filière. Afin de déterminer l'efficacité de la prophylaxie médicale mise en oeuvre, il a donc été procédé à une comparaison des différents schémas de vaccination dans les conditions réelles de production. Il s'avère que les programmes vaccinaux comportant essentiellement des vaccins vivants fournissent une moins bonne protection que ceux qui ont recours aux vaccins inactivés huileux injectables, sans doute à cause du manque de technicité dans l'administration des vaccins vivants. Une primo vaccination associant un vaccin vivant administré individuellement par trempage du bec et une injection de vaccin inactivé huileux procure une bonne protection pendant les dix premières semaines de la vie. Une nouvelle injection à cette période permet d'assurer une couverture pendant toute la durée de l'élevage de la poulette et améliore l'effet de la vaccination par injection à l'entrée en ponte. Dès lors, aucun rappel n'est nécessaire jusqu'à la réforme des pondeuses. (Résumé d'auteur
Anthracycline-Induced Cardiotoxicity: Cardiac Monitoring by Continuous Wave-Doppler Ultrasound Cardiac Output Monitoring and Correlation to Echocardiography
Background: Anthracyclines are agents with a well-known cardiotoxicity. The study sought to evaluate the hemodynamic response to an anthracycline using real-time continuous-wave (CW)-Doppler ultrasound cardiac output monitoring (USCOM) and echocardiography in combination with serum biomarkers. Methods: 50 patients (26 male, 24 female, median age 59 years) suffering from various types of cancer received an anthracycline-based regimen. Patients' responses were measured at different time points (T0 prior to infusion, T1 6 h post infusion, T2 after 1 day, T3 after 7 days, and T4 after 3 months) with CW-Doppler ultrasound (T0-T4) and echocardiography (T1, T4) for hemodynamic parameters such as stroke volume (SV; SVUSCOM ml) and ejection fraction (EF; EFechocardiography%) and with NT-pro-BNP and hs-Troponin T (T0-T4). Results: During the 3-month observation period, the relative decrease in the EF determined by echocardiography was -2.1% (Delta T0-T4, T0 71 +/- 7.8%, T4 69.5 +/- 7%, p = 0.04), whereas the decrease in SV observed using CW-Doppler was -6.5% (Delta T0-T4, T0 54 +/- 19.2 ml, T4 50.5 +/- 20.6 ml, p = 0.14). The kinetics for serum biomarkers were inversely correlated. Conclusions: Combining real-time CW-Doppler USCOM and serum biomarkers is feasible for monitoring the immediate and chronic hemodynamic changes during an anthracycline-based regimen; the results obtained were comparable to those from echocardiography
Common features between neoplastic and preneoplastic lesions of the biliary tract and the pancreas
The bile duct system and pancreas show many similarities due to their anatomical proximity and common embryological origin. Consequently, preneoplastic and neoplastic lesions of the bile duct and pancreas share analogies in terms of
molecular, histological and pathophysiological features. Intraepithelial neoplasms are reported in biliary tract, as biliary intraepithelial neoplasm (BilIN), and in pancreas, as pancreatic intraepithelial neoplasm (PanIN). Both can evolve
to invasive carcinomas, respectively cholangiocarcinoma (CCA) and pancreatic ductal adenocarcinoma (PDAC). Intraductal papillary neoplasms arise in biliary tract and pancreas. Intraductal papillary neoplasm of the biliary tract (IPNB)
share common histologic and phenotypic features such as pancreatobiliary, gastric, intestinal and oncocytic types, and biological behavior with the pancreatic counterpart, the intraductal papillary mucinous neoplasm of the pancreas (IPMN). All these neoplastic lesions exhibit similar immunohistochemical phenotypes, suggesting a common carcinogenic process.
Indeed, CCA and PDAC display similar clinic-pathological features as growth pattern, poor response to conventional chemotherapy and radiotherapy and, as a consequence, an unfavorable prognosis. The objective of this review is to discuss similarities and differences between the neoplastic lesions of the pancreas and biliary tract with potential implications on a common origin from similar stem/progenitor cells
Le concept de maladies virales émergentes : quel risque de zoonose pour La Réunion ?
A La Réunion, le risque d'émergence de maladies virales est constitué par plusieurs zoonoses virales qu'il convient de surveiller: infections à virus Sindbis, virus de l'encéphalite japonaise, virus Wesselsbron, virus Nipah, virus Zika, virus West Nile, virus de la fièvre de la vallée du Rift. La lutte contre ces maladies virales émergentes (MVE) passe par une détection précoce des cas et donc un système de surveillance doté d'un véritable réseau d'information, d'alerte et de prévention international. (Résumé d'auteur
Perioperative latex allergy.
The prevalence of latex allergy varies greatly depending on the population studied and the methods used to detect sensitization. Subjects considered to be at high risk for latex allergy are rubber industry workers, children with spina bifida and urological abnormalities, children undergoing multiple surgical procedures and with urinary catheterization, health care workers and people with food allergy (latex fruit syndrome). In this paper we report a review of latex proteins, the symptoms of latex allergy, diagnosis and management in subjects with latex allergy
Precisely Engineered Supported Gold Clusters as a Stable Catalyst for Propylene Epoxidation
Designing a stable and selective catalyst with high H2 utilisation is of pivotal importance for the direct gas-phase epoxidation of propylene. This work describes a facile one-pot methodology to synthesise ligand-stabilised sub-nanometre gold clusters immobilised onto a zeolitic support (TS-1) to engineer a stable Au/TS-1 catalyst. A non-thermal O2 plasma technique is used for the quick removal of ligands with limited increase in particle size. Compared to untreated Au/TS-1 catalysts prepared using the deposition precipitation method, the synthesised catalyst exhibits improved catalytic performance, including 10 times longer lifetime (>20 days), increased PO selectivity and hydrogen efficiency in direct gas phase epoxidation. The structure-stability relationship of the catalyst is illustrated using multiple characterisation techniques, such as XPS, 31P MAS NMR, DR-UV/VIS, HRTEM and TGA. It is hypothesised that the ligands play a guardian role in stabilising the Au particle size, which is vital in this reaction. This strategy is a promising approach towards designing a more stable heterogeneous catalyst
Gold nanoparticles with tailored size through ligand modification for catalytic applications
The active sites of catalysts can be tuned by using appropriate organic moieties. Here, we describe a facile approach to synthesise gold nanoparticles (AuNPs) using various Au(I) precursors. The core size of these AuNPs can be precisely tailored by varying the steric hindrance imposed by bound ligands. An interesting relationship is deduced that correlates the steric hindrance around the metal to the final size of the nanoparticles. The synthesised AuNPs are immobilised onto TS-1 zeolite (Au/TS-1) with minimal change in the final size of the AuNPs. The catalytic performance of Au/TS-1 catalyst is evaluated for the direct gas phase epoxidation of propylene with hydrogen and oxygen, an environmentally friendly route to produce propylene oxide. The results indicate that smaller AuNPs exhibit enhanced catalytic activity and selectivity. Furthermore, this synthetic approach is beneficial when tailored synthesis of gold nanoparticles of specific sizes is required
Global Production Increased by Spatial Heterogeneity in a Population Dynamics Model
Spatial and temporal heterogeneity are often described as important factors having a strong impact on biodiversity. The effect of heterogeneity is in most cases analyzed by the response of biotic interactions such as competition of predation. It may also modify intrinsic population properties such as growth rate. Most of the studies are theoretic since it is often difficult to manipulate spatial heterogeneity in practice. Despite the large number of studies dealing with this topics, it is still difficult to understand how the heterogeneity affects populations dynamics. On the basis of a very simple model, this paper aims to explicitly provide a simple mechanism which can explain why spatial heterogeneity may be a favorable factor for production.We consider a two patch model and a logistic growth is assumed on each patch. A general condition on the migration rates and the local subpopulation growth rates is provided under which the total carrying capacity is higher than the sum of the local carrying capacities, which is not intuitive. As we illustrate, this result is robust under stochastic perturbations
VALUTAZIONE DELLA CLEARANCE DI HCV-RNA SOTTO TRATTAMENTO ANTIVIRALE CON TRANSCRIPTION-MEDIATED AMPLIFICATION (TMA)
n/
- …