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991.
During speech perception, acoustic correlates of syllable structure and pitch periodicity are directly reflected in electrophysiological brain activity. Magnetoencephalography (MEG) recordings were made while 10 participants listened to natural or formant‐synthesized speech at moderately fast or ultrafast rate. Cross‐correlation analysis was applied to show brain activity time‐locked to the speech envelope, to an acoustic marker of syllable onsets, and to pitch periodicity. The envelope yielded a right‐lateralized M100‐like response, syllable onsets gave rise to M50/M100‐like fields with an additional anterior M50 component, and pitch (ca. 100 Hz) elicited a neural resonance bound to a central auditory source at a latency of 30 ms. The strength of these MEG components showed differential effects of syllable rate and natural versus synthetic speech. Presumingly, such phase‐locking mechanisms serve as neuronal triggers for the extraction of information‐bearing elements. 相似文献
992.
993.
994.
Rolf Weimer Sabine Deisz Hartmut Dietrich Fabrice Renner Rolf‐Hasso Bödeker Volker Daniel Shirin Kamali‐Ernst Wolfgang Ernst Winfried Padberg Gerhard Opelz 《Transplant international》2011,24(6):596-609
The Symphony study showed superior 1‐year kidney graft outcome in patients on immunosuppression with tacrolimus/mycophenolate mofetil (Tacr/MMF). To analyze whether differences in clinical outcome between maintenance regimens may be explained by their impact on clinically relevant immune parameters, we assessed CD4 helper activity, immunoglobulin‐secreting cell (ISC) formation, neopterin, sCD30, and intracellular cytokine production in a prospective study in 77 renal transplant recipients treated with cyclosporine A/azathioprine (CsA/Aza), CsA/MMF, Tacr/Aza or Tacr/MMF at 2 years post‐transplant. Tacr‐ compared with CsA‐based immunosuppression was independently associated with increased IL‐2 (P < 0.0001, CD4 cells; P = 0.014, CD8 cells) and CD4 cell IL‐4 responses (P = 0.046; stepwise logistic regression) resulting in physiological responses in Tacr/Aza patients as compared with 25 healthy controls. MMF versus Aza treatment was proven to be an independent variable associated with suppression of CD4 cell IL‐10 responses (P = 0.008), B‐cell IL‐6R expression (P < 0.0001) and ISC formation [P = 0.020, staphylococcus cowan strain I (SAC I); P = 0.021, pokeweed mitogen (PWM)]. Our data suggest that Tacr/MMF had the most effective impact on graft protective Th2 responses (enhanced CD4 cell IL‐4 by Tacr, decreased CD4 cell IL‐10 responses by MMF) and suppression of B‐cell functions (MMF), whereas Tacr/Aza was associated with physiological IL‐2 and IL‐4 and stronger humoral responses which may reduce the risk of infectious disease complications. (ClinicalTrials.gov number: NCT00150891). 相似文献
995.
Frank CB Adams M Kroeber M Wentzensen A Heppert V Schulte-Bockholt D Guehring T 《Archives of orthopaedic and trauma surgery》2011,131(10):1389-1396
Introduction
It is unknown whether intraoperative subcutaneous wound closing culture samples (WCCS) are useful to predict periprosthetic joint infection (PJI). 相似文献996.
Wallon M Kieffer F Binquet C Thulliez P Garcia-Méric P Dureau P Franck J Peyron F Bonnin A Villena I Bonithon-Kopp C Gouyon JB Masson S Félin A Cornu C 《Thérapie》2011,66(6):473-480
In France, children with confirmed congenital toxoplasmosis receive a treatment for a period of 12 to 24 months. Such prolonged treatment may generate potentially severe risks, in particular hematologic and cutaneous. Our objective is to compare the effectiveness of two therapeutic strategies on the prevention of retinochoroiditis by a randomized, non-inferiority, open-label, parallel study including 486 children, 3 to 6 months of age with a non-severe form of congenital toxoplasmosis. Following randomization, pyrimethamine-sulphonamide treatment is initiated for a period of three months, followed by a treatment with Fansidar(?) for 9 months, or therapeutic abstention. Follow-up visits during a two-year period will include an examination of the eye, a blood test, and questionnaires to evaluate the children's quality of life and their parents' anxiety. Confirming the non-inferiority of the effectiveness of a short-term treatment will improve the quality of life of parents and children. 相似文献
997.
998.
Ilker Uçkay Jorge Garbino Pierre-Yves Dietrich Béatrice Ninet Peter Rohner Véronique Jacomo 《BMC infectious diseases》2006,6(1):1-5
Background
A reliable prediction of the causative agent of community-acquired pneumonia (CAP) is not possible based on clinical features. Our aim was to test, whether the measurement of the expression of complement receptors or Fcγ receptors on neutrophils and monocytes would be a useful preliminary test to differentiate between bacterial and viral pneumonia.Methods
Sixty-eight patients with CAP were studied prospectively. Thirteen patients had pneumococcal pneumonia; 13 patients, influenza A pneumonia; 5 patients, atypical pneumonia, and 37 patients, aetiologically undefined pneumonia. Leukocyte receptor expression was measured within 2 days of hospital admission.Results
The mean expression of complement receptor 1 (CR1) on neutrophils was significantly higher in the patients with pneumococcal pneumonia than in those with influenza A pneumonia. The mean expression of CR1 was also significantly higher in aetiologically undefined pneumonia than in influenza A pneumonia, but there was no difference between pneumococcal and undefined pneumonia.Conclusion
Our results suggest that the expression of CR1 is higher in classical bacterial pneumonia than in viral pneumonia. Determination of the expression of CR1 may be of value as an additional rapid tool in the aetiological diagnosis, bacterial or viral infection, of CAP. These results are preliminary and more research is needed to assess the utility of this new method in the diagnostics of pneumonia. 相似文献999.
An estimated 2 billion people are latently infected with Mycobacterium tuberculosis, the majority of which are already BCG vaccinated and repeatedly sensitized to mycobacterial strains from the environment. To be successful in the high endemic regions, any future TB vaccine strategy will have to be tailored in accordance with the resulting complexity of the TB infection and anti-mycobacterial immune response. In this review we will discuss some of the most advanced attempts to address this challenge. 相似文献
1000.
Alexander Yang MD Jaap Ruiter MD Dietrich Pfeiffer MD Bahman Esmailzadeh MD Armin Welz MD Marc Hochhusler MD Georg Nickenig MD Berndt Lüderitz MD Thorsten Lewalter MD 《Heart rhythm》2006,3(6):682-688
BACKGROUND: The population of patients likely to respond to selected pacing algorithms for maintenance of sinus rhythm is unknown. OBJECTIVES: The purpose of this study was to identify patients with specific onset patterns of paroxysmal atrial fibrillation (AF). METHODS: Dual-chamber pacemakers with advanced diagnostic functions were implanted in 112 patients with conventional indications for antibradycardia pacing and a history of paroxysmal AF. Pacemaker diagnostic data were analyzed after 97.5 +/- 40.9 days. According to the frequency of premature atrial contractions (PACs) during the 5 minutes before AF onset, patients were assigned to one of three groups: group A (high PAC activity), group B (moderate PAC activity), or group C (low PAC activity). RESULTS: AF burden was lower in group A (4.6% +/- 2.4%) than group B (15.8% +/- 3.0%, P = .003) and group C (15.5% +/- 3.1%, P = .003). Fewer AF episodes occurred in group A (2.1 +/- 1.3 per day) than group B (3.8 +/- 1.2 per day, P = .006). Mean AF episode duration was shorter in group A (11.4 +/- 10.2 hours) than group C (41.4 +/- 27.5 hours, P = .03). CONCLUSION: The coincidence of low PAC activity before AF onset, high AF burden, and extended arrhythmia episode duration appears to be the consequence of a high atrial substrate factor. In these "substrate fibrillators," the efficacy of pacing algorithms for maintenance of sinus rhythm may be limited. In contrast, "trigger fibrillators" exhibiting low AF burden despite high PAC incidence may represent the target population for specific PAC-suppressing pacing algorithms. 相似文献