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排序方式: 共有4977条查询结果,搜索用时 31 毫秒
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Florian Grahammer Nora Haenisch Frederic Steinhardt Lukas Sandner Malte Roerden Frederic Arnold Tomke Cordts Nicola Wanner Wilfried Reichardt Dontscho Kerjaschki Markus A. Ruegg Michael N. Hall Pierre Moulin Hauke Busch Melanie Boerries Gerd Walz Ferruh Artunc Tobias B. Huber 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(27):E2817-E2826
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AA Righetti AY Koua LG Adiossan D Glinz RF Hurrell EK N'goran S Niamké R Wegmüller J Utzinger 《The American journal of tropical medicine and hygiene》2012,87(3):425-434
Anemia affects one-quarter of the world''s population, but its etiology remains poorly understood. We determined the prevalence of anemia and studied underlying risk factors in infants (6–23 months), young school-aged children (6–8 years), and young non-pregnant women (15–25 years) in south-central Côte d''Ivoire. Blood, stool, and urine samples were subjected to standardized, quality-controlled methods. We found high prevalence of anemia, malaria, inflammation, and deficiencies of iron, riboflavin, and vitamin A but low prevalence and intensities of soil-transmitted helminth and schistosome infections. Multivariate regression analysis revealed significant associations between anemia and Plasmodium falciparum for infants, inflammation for school-aged children, and cellular iron deficiency for both school-aged children and non-pregnant women. Women with riboflavin deficiency had significantly lower odds of anemia. Our findings call for interventions to protect infants from malaria, improved intake of dietary iron, better access to health care, and health education. 相似文献
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Purpose: The aim of this study was to investigate the influence of the crown‐to‐implant length ratio (c/i ratio) on the implant survival, changes of the marginal bone level (MBL) and the occurrence of biological and technical complications. Material and methods: This cross‐sectional retrospective study included all patients with implants in the posterior segments supporting single crown restorations with a minimum follow‐up of 5 years. All patients were questioned and examined clinically and radiographically. The technical and biological c/i ratio and the MBL were measured on digitized periapical radiographs. The following outcome parameters in relation to the c/i ratio and the co‐factors were statistically analyzed: implant survival rate, MBL, occurrence of technical and biological complications. For statistical analysis, regression, correlation and survival analyses were applied (P<0.05). Results: Seventy patients (mean age of 50.7 years [range 19.8–76.6 years]) with a total of 100 implants (24 Straumann type, 76 Brånemark type) were included in this study. The mean follow‐up period was 6.2 years (range 4.73–11.7 years). Six implants failed during the follow‐up period, yielding a cumulative survival rate of 95.8% at 5 years in function. The mean technical c/i ratio was 1.04 (±0.26, range 0.59–2.01). The mean biological c/i ratio was 1.48 (±0.42, range 0.82–3.24). No statistically significant influence of the technical and biological c/i ratio was found on the implant survival, MBL and occurrence of technical and biological complications. When adjusted for the biological c/i ratio, smoking was the only co‐factor significantly associated with implant failure and biological complications. Conclusion: In the present study, the c/i ratio did not influence the clinical performance of implants supporting single crown restorations in the posterior segments of the jaw within the range tested. To cite this article: Schneider D, Witt L, Hämmerle CHF. Influence of the crown‐to‐implant length ratio on the clinical performance of implants supporting single crown restorations: a cross‐sectional retrospective 5‐year investigation.Clin. Oral Impl. Res. 23 , 2012; 169–174. doi: 10.1111/j.1600‐0501.2011.02230.x 相似文献
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Marina Komrakova Stephan Sehmisch Mohammad Tezval Jan Ammon Peggy Lieberwirth Cordula Sauerhoff Lukas Trautmann Michael Wicke Christian Dullin Klaus M. Stuermer Ewa K. Stuermer 《Calcified tissue international》2013,92(6):509-520
Numerous whole-body vibration (WBV) devices of various forces are available on the market, although their influence on the musculoskeletal system is not yet understood. The effect of different WBVs on bone healing and muscle function was evaluated in rats ovariectomized at 3 months of age. 2 months after ovariectomy, bilateral metaphyseal tibia osteotomy and T-plate osteosynthesis were performed. Rats were divided into groups: intact, OVX, and OVX exposed to vertical WBVs of 35, 50, 70, or 90 Hz (experiment 1) or horizontal WBVs of 30, 50, 70, or 90 Hz (experiment 2) 5 days after osteotomy (0.5 mm, 15 min/day for 30 days). The tibia and gastrocnemius and soleus muscles were collected. Vertical vibrations (>35 Hz) improved cortical and callus densities, enlarged callus area and width, suppressed the tartrate-resistant acid phosphatase gene, enhanced citrate synthase activity, accelerated osteotomy bridging (35 and 50 Hz), upregulated the osteocalcin (Oc) gene (70 Hz), and increased relative muscle weight (50 Hz). Horizontal vibrations reduced cortical width (<90 Hz) and callus density (30 Hz), enhanced alkaline phosphatase (Alp) gene expression (50 Hz), decreased the size of oxidative fibers (35 and 70 Hz), and increased capillary density (70, 90 Hz). Biomechanical data; serum Oc, Alp, and creatine kinase activities; body weight; and food intake did not change after WBVs. Vertical WBVs of 35 and 50 Hz produced more favorable results than the higher frequencies. Horizontal WBV showed no positive or negative effects. Further studies are needed to elucidate the effects of WBV on different physiological systems, and precautions must be taken when implementing WBV in the treatment of patients. 相似文献
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