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Der Freie Zahnarzt - Die chemomechanische Aufbereitung des Wurzelkanalsystems stellt den wichtigsten Bestandteil der endodontischen Therapie dar und beeinflusst den Erfolg der Behandlung...  相似文献   
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In chickens, the nematode Ascaridia galli is found with prevalences of up to 100% causing economic losses to farmers. No avian nematode vaccines have yet been developed and detailed knowledge about the chicken immune response towards A. galli is therefore of great importance. The objective of this study was to evaluate the induction of protective immune responses to A. galli soluble antigen by different immunization routes. Chickens were immunized with a crude extract of A. galli via an oral or intra-muscular route using cholera toxin B subunit as adjuvant and subsequently challenged with A. galli. Only chickens immunized via the intra-muscular route developed a specific A. galli antibody response. Frequencies of γδ T cells in spleen were higher 7 days after the first immunization in both groups but only significantly so in the intra-muscularly immunized group. In addition, systemic immunization had an effect on both Th1 and Th2 cytokines in caecal tonsils and Meckel's diverticulum. Thus both humoral and cellular immune responses are inducible by soluble A. galli antigen, but in this study no protection against the parasite was achieved.  相似文献   
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Natural oils are advocated and used throughout the world as part of neonatal skin care, but there is an absence of evidence to support this practice. The goal of the current study was to ascertain the effect of olive oil and sunflower seed oil on the biophysical properties of the skin. Nineteen adult volunteers with and without a history of atopic dermatitis were recruited into two randomized forearm‐controlled mechanistic studies. The first cohort applied six drops of olive oil to one forearm twice daily for 5 weeks. The second cohort applied six drops of olive oil to one forearm and six drops of sunflower seed oil to the other twice daily for 4 weeks. The effect of the treatments was evaluated by determining stratum corneum integrity and cohesion, intercorneocyte cohesion, moisturization, skin‐surface pH, and erythema. Topical application of olive oil for 4 weeks caused a significant reduction in stratum corneum integrity and induced mild erythema in volunteers with and without a history of atopic dermatitis. Sunflower seed oil preserved stratum corneum integrity, did not cause erythema, and improved hydration in the same volunteers. In contrast to sunflower seed oil, topical treatment with olive oil significantly damages the skin barrier, and therefore has the potential to promote the development of, and exacerbate existing, atopic dermatitis. The use of olive oil for the treatment of dry skin and infant massage should therefore be discouraged. These findings challenge the unfounded belief that all natural oils are beneficial for the skin and highlight the need for further research.  相似文献   
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Multiple studies comparing sirolimus-eluting stents (SES) and paclitaxel-eluting stents (PES) in patients with coronary artery disease have been performed. Despite these comparisons, it remains uncertain whether a differential in long-term efficacy and safety exists. Unselected patients treated exclusively with 1 drug-eluting stent type were enrolled in the Registry Experience at the Washington Hospital Center with Drug-Eluting Stents. There were 2,099 patients (3,766 lesions) treated with SES and 1,079 patients (1,850 lesions) treated with PES. Patients were followed at 30 days, 1 year, and 2 years for the clinical endpoints of death, myocardial infarction, target vessel revascularization, and definite and definite/probable stent thrombosis. Patients in the SES group had more dyslipidemia, history of congestive heart failure, and ostial lesions; patients treated with PES had more previous coronary artery bypass surgery, unstable angina, and type C lesions. At 2 years, unadjusted major adverse cardiac events (MACE) (22.6% vs 21.1%, p = 0.3) and target vessel revascularization (13.3% vs 11.2%, p = 0.1) were comparable. The incidence of definite stent thrombosis was higher in the SES group (1.8% vs 0.9%, p = 0.05) driven by early events. Similar results were seen after adjustment for baseline differences: MACE (hazard ratio 1.1, 95% confidence interval [CI] 0.9 to 1.3, p = 0.5), definite stent thrombosis (hazard ratio 2.3, 95% CI 1.0 to 5.2, p = 0.05), and target vessel revascularization (hazard ratio 1.1, 95% CI 0.9 to 1.4, p = 0.4). The incidence and rate of late stent thrombosis (>30 days) were similar (0.7% vs 0.5%, p = 0.4 and 0.24%/year, both groups, respectively). In conclusion, no major differential in long-term safety or efficacy was detected between SES and PES; both stent types were efficacious in reducing revascularization but were limited by a small continual increase in late stent thrombosis.  相似文献   
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