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31.
Monoclonal antibodies specific for the two types of wall-forming bodies of Eimeria tenella macrogametes (Coccidia, Apicomplexa) 总被引:1,自引:0,他引:1
Two monoclonal antibodies (mAbs) raised against the macrogamonts of Eimeria tenella identified antigens located in the wall-forming bodies of type I (WF I) and type II (WF II) by indirect immunofluorescence and by immunoelectron microscopy. With these mAbs, the involvement of both types of wall-forming body at the protein level in the formation of the inner and outer oocyst walls of E. tenella was shown by indirect immunofluorescence assay. On Western blots of pure macrogamont, mAb E1D8 against WF I reacted with a series of bands between 42 kDa and 105 kDa. In pure, unsporulated extract, this mAb recognized a complex of bands between 26 kDa and 153 kDa. mAb E2E5 against WF II, on Western blots of pure extract of macrogamonts, recognized an antigen of 51 kDa. Later in the development, after the formation of the inner oocyst wall, mAb E2E5 reacted with three polypeptide of 23, 25 and 30 kDa. Proteolytic processing may be forwarded as the mechanism regulating the distinct regulation protein involved in the oocyst wall. 相似文献
32.
Squires K Lazzarin A Gatell JM Powderly WG Pokrovskiy V Delfraissy JF Jemsek J Rivero A Rozenbaum W Schrader S Sension M Vibhagool A Thiry A Giordano M 《Journal of acquired immune deficiency syndromes (1999)》2004,36(5):1011-1019
BACKGROUND: Atazanavir, an azapeptide protease inhibitor (PI), has pharmacokinetics that allow once-daily dosing, and it is not associated with significant PI-associated dyslipidemia. METHODS: A randomized, double-blind, double-dummy, active-controlled, 2-arm study comparing the antiviral efficacy and safety of atazanavir 400 mg administered once daily with efavirenz 600 mg administered once daily in combination with open-label fixed-dose zidovudine plus lamivudine twice daily. The 810 treatment-naive patients were stratified by HIV RNA level. The primary efficacy end point was the proportion of treated patients with HIV RNA levels <400 copies/mL through week 48. RESULTS: At week 48, HIV RNA levels were <400 copies/mL in 70% of patients receiving atazanavir and 64% of patients receiving efavirenz (intent-to-treat, difference; 95% confidence interval: 5.2%; -1.2%, 11.7%). Median CD4 cell counts increased at comparable magnitudes and rates in the 2 treatment arms (mean change at week 48: 176 cells/mm with atazanavir, 160 cells/mm with efavirenz). Atazanavir-treated patients relative to comparator-treated patients did not demonstrate significant increases in total cholesterol, fasting low-density lipoprotein cholesterol, or fasting triglycerides over 48 weeks of therapy. Atazanavir-linked bilirubin elevations infrequently resulted in treatment discontinuation (<1%). Atazanavir treatment did not increase fasting glucose or insulin levels. CONCLUSIONS: For initial HIV treatment, a highly active antiretroviral therapy regimen of atazanavir/zidovudine/lamivudine is as efficacious and well tolerated as the combination of efavirenz/zidovudine/lamivudine. 相似文献
33.
34.
Jean-Henri Gaudy Jean-François Sicard Raymond Maneglia Marielle Quignon 《Journal canadien d'anesthésie》1993,40(9):883-890
L’halothane diminue la réponse ventilatoire à l’hypoxie et l’activité des chémorécepteurs artériels périphériques, réalisant une «chémodénervation chimique». Afin d’évaluer le rôle de cette «chémodénervation chimique» dans les modifications de l’équilibre acido-basique et des gaz du sang artériel provoquées par l’halothane, ces paramètres ont été mesurés chez des rats intacts éveillés, puis anesthésiés, et chez des rats chémodénervés, éveillés puis anesthésiés. Le niveau de l’anesthésie pouvant être modifié par la chémodénervation anatomique, l’ED50 inspirée d’halothane a été mesurée chez six rats avant et après chémodénervation anatomique. D’éventuelles modifications hémodynamiques dues à l’halothane et /ou à la chémodénervation anatomique pouvant interférer avec les résultats, la pression artérielle systémique et la fréquence cardiaque ont été mesurées chez six rats intacts éveillés, puis anesthésiés, et chez les six mêmes rats chémodénervés, éveillés puis anesthésiés. Chez neuf rats intacts et chez 19 rats chémodénervés, le pH artériel, la concentration artérielle de bicarbonates, et les gaz du sang artériel (PaO2 et PaCO2) ont été mesurés avant et après administration d’halothane. La chémodénervation anatomique ne modifia ni l’ED50 inspirée (1,1%), ni la pression artérielle moyenne et la fréquence cardiaque. Les effets hémodynamiques de l’halothane furent comparables chez les rats intacts et chez les rats chémodénervés. Les modifications des gaz du sang et de l’équilibre acido-basique provoquees par l’halothane chez les rats intacts, et par la chémodénervation anatomique chez les rats éveillés, ne furent pas significativement différentes: diminution significative de PaO2 et de pHa, augmentation significative de PaCO2 Chez les rats chémodénervés, l’halothane provoqua une diminution supplémental de PaO2 et une augmentation supplémentaire de PaCO2. Le fait que l’halothane et que la chémodénervation anatomique modifient de la même manière les gaz du sang et l’équilibre acido-basique est en faveur de l’action «chémodénervatrice chimique» de l’halothane. Mais les effets additionnels de l’halothane chez l’animal chémodénervé anatomiquement confirment que les effets de l’halothane sur les gaz du sang et l’équilibre acido-basique résultent de multiples points d’impact sur le système respiratoire. 相似文献
35.
Jean-François Le Gargasson Michel Paques Jean-Eric Guez Bernadette Boval Eric Vicaut Xin Hou Yvon Grall Alain Gaudric 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1997,235(1):56-58
Purpose: To demonstrate the feasibility of a technique for the visualization by scanning laser ophthalmoscope (SLO) of fluores cein-labelled autologous leukocytes and platelets in retinal vessels. Method: Individual blood samples from rats and rabbits were centrifuged to isolate platelets and leukocytes, then passively labelled with fluorescein and reinjected into the same animal. An SLO was used to visualize and record cell displacement in the retinal circulation. Labelled platelets were analysed by flow cytometry. Results: By SLO, platelets appeared as a heterogeneous particle flow, and individual leukocytes appearing as brighter spots could easily be traced. Flow cytometry showed that after labelling platelets were well individualized and their size was slightly increased. Conclusion: Circulating blood cells can be visualized in retinal vessels by a simple method consisting of passive labelling of autologous platelets and leukocytes by fluorescein. No platelet toxicity was detected. This method could be applied to the study of blood cell movement in human retinal vascular diseases.Proprietary interest category: N 相似文献
36.
Tri-dimensional automatic segmentation of PET volumes based on measured source-to-background ratios: influence of reconstruction algorithms. 总被引:10,自引:0,他引:10
Jean-Fran?ois Daisne Mérence Sibomana Anne Bol Thomas Doumont Max Lonneux Vincent Grégoire 《Radiotherapy and oncology》2003,69(3):247-250
A method for automatic volume segmentation of functional imaging based on a relationship between source-to-background ratio and the iso-activity level to be used is described. Such method, which has been established with radioactive spheres in a phantom, is independent of the a priori knowledge of the lesion of interest and is valid for small (>2 ml) and/or poorly contrasted (S/B>1.5) lesions. Accuracy varies slightly with the image reconstruction algorithm used. 相似文献
37.
Fran?ois L'Hériteau Corinne Alberti Yves Cohen Gilles Troché Pierre Moine Jean-Fran?ois Timsit 《Infection control and hospital epidemiology》2005,26(1):13-20
OBJECTIVES: To evaluate nosocomial infection (NI) surveillance strategies in French ICUs and to identify similar patterns defining subsets within which comparisons can be made. DESIGN: A questionnaire was sent to all French ICUs, and a random sample of nonresponders was interviewed. PARTICIPANTS: Three hundred ninety-five responder ICUs (69%) in France. RESULTS: In 282 ICUs (71%), a dedicated ICU staff member was responsible for infection control activities. The microbiology laboratory was usually in the hospital (90%) and computerized (94%) but issued regular hospital microbiology records in only 48% of cases. Patients receiving mechanical ventilation, central venous catheterization, and urinary catheterization were 90%, 79%, and 60%, respectively. Patients were screened for carriage of multidrug-resistant bacteria on admission and during the stay in 70% and 60% of ICUs, respectively, most often targeting MRSA. Quantitative cultures were used to diagnose ventilator-associated pneumonia (VAP) in 90% of ICUs, including distal specimens in 80% and bronchoscopy specimens in 60%. Quantitative central venous catheter (CVC)-segment cultures were used in 70% of ICUs. All CVCs were cultured routinely in 53% of the ICUs. Despite wide variations in infection control and surveillance strategies, multiple correspondence analysis identified 13 key points (4 structural variables and 9 variables concerning the diagnosis of VAP, the surveillance and diagnosis of catheter-related and urinary tract infections, and the mode of screening of MRSA carriers) that categorize the variability of French ICUs' approaches to NIs. CONCLUSION: This study revealed profound differences in NI surveillance strategies across ICUs, indicating a need for caution when using NI surveillance data for comparisons and benchmarking. 相似文献
38.
Muriel Gugger Séverine Lenoir Céline Berger Aurélie Ledreux Jean-Claude Druart Jean-Fran?ois Humbert Catherine Guette Cécile Bernard 《Toxicon》2005,45(7):919-928
The first identification of anatoxin-a in a French lotic system is reported. Rapid deaths of dogs occurred in 2003 after the animals drank water from the shoreline of the La Loue River in eastern France. Sediments, stones and macrophytes surfaces at the margin of the river were covered by a thick biofilm containing large quantities of several benthic species of filamentous, non-heterocystous cyanobacteria. Known cyanotoxins, such as microcystins, saxitoxins and anatoxins were screened from biofilm samples by biochemical and analytical assays. A compound with similar UV spectra to the anatoxin-a standard was detected by high-performance liquid chromatography (HPLC) coupled with photo-diode array detector. This toxin was further identified by HPLC coupled with a UV detector and by electrospray ionisation-Quadrupole-Time-Of-Flight mass spectrometer, and confirmed by tandem mass spectrometry. These two techniques were necessary to discriminate anatoxin-a in phenylalanine-containing matrices such as liver samples of poisoned dogs. The toxin and the aromatic amino acid, phenylalanine, present the same pseudomolecular ion at m/z 166, but have differing fragmentation patterns, retention times and UV spectra. Finally, several cyanobacterial strains were isolated from the green biofilm and tested for anatoxin-a production. Phormidium favosum was identified as a new anatoxin-a producing species. 相似文献
39.
Early variations of circulating interleukin-6 and interleukin-10 levels during thoracic radiotherapy are predictive for radiation pneumonitis. 总被引:5,自引:0,他引:5
Dominique Arpin David Perol Jean-Yves Blay Lionel Falchero Line Claude Sylvie Vuillermoz-Blas Isabelle Martel-Lafay Chantal Ginestet Laurent Alberti Dimitri Nosov Bénédicte Etienne-Mastroianni Vincent Cottin Maurice Perol Jean-Claude Guerin Jean-Fran?ois Cordier Christian Carrie 《Journal of clinical oncology》2005,23(34):8748-8756
PURPOSE: To investigate variations of circulating serum levels of interleukin-6 (IL-6), tumor necrosis factor alpha (TNFalpha), and interleukin-10 (IL-10) during three-dimensional conformal radiation therapy (3D-CRT) in patients with non-small-cell lung cancer and correlate these variations with the occurrence of radiation pneumonitis. PATIENTS AND METHODS: Ninety-six patients receiving 3D-CRT for stage I to III disease were evaluated prospectively. Circulating cytokine levels were determined before, every 2 weeks during, and at the end of treatment. Radiation pneumonitis was evaluated prospectively between 6 and 8 weeks after 3D-CRT. The predictive value of clinical, dosimetric, and biologic (cytokine levels) factors was evaluated both in univariate and multivariate analyses. RESULTS: Forty patients (44%) experienced score 1 or more radiation pneumonitis. No association was found between baseline cytokine levels and the risk of radiation pneumonitis. In the whole population, mean levels of TNFalpha, IL-6, and IL-10 remained stable during radiotherapy. IL-6 levels were significantly higher (P = .047) during 3D-CRT in patients with radiation pneumonitis. In the multivariate analysis, covariations of IL-6 and IL-10 levels during the first 2 weeks of 3D-CRT were evidenced as independently predictive of radiation pneumonitis in this series (P = .011). CONCLUSION: Early variations of circulating IL-6 and IL-10 levels during 3D-CRT are significantly associated with the risk of radiation pneumonitis. Variations of circulating IL-6 and IL-10 levels during 3D-CRT may serve as independent predictive factors for this complication. 相似文献