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排序方式: 共有4227条查询结果,搜索用时 15 毫秒
81.
Kohorst P Herzog TJ Borchers L Stiesch-Scholz M 《European journal of oral sciences》2007,115(2):161-166
The aim of this in vitro study was to compare the load-bearing capacity of posterior four-unit fixed partial dentures (FPDs) produced with two different yttria-stabilized polycrystalline tetragonal zirconia (Y-TZP) ceramics, one being a presintered material, the other a fully sintered, hot isostatically pressed material. Additionally, as a novel approach, the influence of preliminary mechanical damage upon the fracture force of an FPD has been investigated. A total of 20 frameworks each were milled from presintered zirconia and from fully sintered zirconia. Prior to veneering, 10 frameworks of each material were 'damaged' by a defined saw cut similar to an accidental flaw generated during shape cutting. Before fracture testing, all FPDs were subjected to thermal and mechanical cycling. Additionally, scanning electron microscopy was used to investigate fracture surfaces. Statistical analysis showed that FPDs milled from fully sintered zirconia had a significantly higher fracture resistance compared with specimens made from presintered material, whereas preliminary damage did not have a significant effect. After aging, FPDs made from both materials were capable of withstanding occlusal forces reported in the literature. Therefore, both types of Y-TZP may be suitable for posterior four-unit all-ceramic FPDs, although further prolonged aging experiments and prospective clinical trials are required to prove their fitness for clinical use. 相似文献
82.
Construct and predictive validity of a self-reported measure of preclinical mobility limitation 总被引:1,自引:0,他引:1
Mänty M Heinonen A Leinonen R Törmäkangas T Sakari-Rantala R Hirvensalo M von Bonsdorff MB Rantanen T 《Archives of physical medicine and rehabilitation》2007,88(9):1108-1113
OBJECTIVES: To validate self-reported preclinical mobility limitation concept and self-report assessment method against muscle power and walking speed, and to study the predictive validity of preclinical mobility limitation with respect to future risk of manifest mobility limitation. DESIGN: Observational prospective cohort study and cross-sectional analysis. SETTING: Research laboratory and community. PARTICIPANTS: A total of 632 community-living (age range, 75-81 y) women and men took part in the baseline assessments and 302 persons in the semi-annual interviews on mobility limitation over 2 years. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Walking speed, muscle power, and self-reported preclinical and manifest mobility limitation. Preclinical mobility limitation was defined as self-reported tiredness or modification of task performance without task difficulty. At baseline, 4 subgroups were created according to self-reported preclinical mobility limitation in any of 3 mobility tasks (walking 2 km, walking 0.5 km, climbing up stairs): no limitation, preclinical limitation, and minor and major manifest limitation. RESULTS: At baseline, participants with preclinical mobility limitation showed intermediate levels of walking speed and muscle power, compared with those with no limitation or manifest mobility limitation. Participants reporting baseline preclinical mobility limitation had 3- to 6-fold higher age- and sex-adjusted risk of progressing to major manifest mobility limitation during the 2-year follow-up compared with participants with no limitation at baseline, whereas the risk among those with minor limitation at baseline was 14- to 18-fold higher compared with those with no limitation. CONCLUSIONS: The self-report assessment tool proved to be a valid measure to capture the early signs of disability and may serve as an inexpensive tool for identifying those nondisabled persons at high risk for future disability. 相似文献
83.
Timo Rantalainen Rachel L. Duckham Harri Suominen Ari Heinonen Markku Alén Marko T. Korhonen 《Calcified tissue international》2014,95(2):132-140
High impact loading is known to prevent some of the age-related bone loss but its effects on the density distribution of cortical bone are relatively unknown. This study examined the effects of age and habitual sprinting on tibial and fibular mid-shaft bone traits (structural, cortical radial and polar bone mineral density distributions). Data from 67 habitual male sprinters aged 19–39 and 65–84 years, and 60 non-athletic men (referents) aged 21–39 and 65–80 years are reported. Tibial and fibular mid-shaft bone traits (strength strain index SSI, cortical density CoD, and polar and radial cortical density distributions) were assessed with peripheral quantitative computed tomography. Analysis of covariance (ANCOVA) adjusted for height and body mass indicated that the sprinters had 21 % greater tibial SSI (P < 0.001) compared to the referents, with no group × age-group interaction (P = 0.54). At the fibula no group difference or group × age-group interaction was identified (P = 0.12–0.81). For tibial radial density distribution ANCOVA indicated no group × radial division (P = 0.50) or group × age-group × division interaction (P = 0.63), whereas an age × radial division interaction was observed (P < 0.001). For polar density distribution, no age-group × polar sector (P = 0.21), group × polar sector (P = 0.46), or group × age-group × polar sector interactions were detected (P = 0.15). Habitual sprint training appears to maintain tibial bone strength, but not radial cortical density distribution into older age. Fibular bone strength appeared unaffected by habitual sprinting. 相似文献
84.
Ushanandini Mohanraj Maija Jokinen Rajita Rayamajhi Thapa Minna Paloniemi Timo Vesikari Maija Lappalainen Eveliina Tarkka Zaiga Nora-Krkle Anda Vilmane Kim Vettenranta Charles Mangani Sami Oikarinen Yue-Mei Fan Per Ashorn Elina Visnen Maria Sderlund-Venermo 《Viruses》2021,13(3)
Three human protoparvoviruses, bufavirus (BuV), tusavirus (TuV) and cutavirus (CuV), have recently been discovered in diarrheal stool. BuV has been associated with diarrhea and CuV with cutaneous T-cell lymphoma, but there are hardly any data for TuV or CuV in stool or respiratory samples. Hence, using qPCR and IgG enzyme immunoassays, we analyzed 1072 stool, 316 respiratory and 445 serum or plasma samples from 1098 patients with and without gastroenteritis (GE) or respiratory-tract infections (RTI) from Finland, Latvia and Malawi. The overall CuV-DNA prevalences in stool samples ranged between 0–6.1% among our six patient cohorts. In Finland, CuV DNA was significantly more prevalent in GE patients above rather than below 60 years of age (5.1% vs 0.2%). CuV DNA was more prevalent in stools among Latvian and Malawian children compared with Finnish children. In 10/11 CuV DNA-positive adults and 4/6 CuV DNA-positive children with GE, no known causal pathogens were detected. Interestingly, for the first time, CuV DNA was observed in two nasopharyngeal aspirates from children with RTI and the rare TuV in diarrheal stools of two adults. Our results provide new insights on the occurrence of human protoparvoviruses in GE and RTI in different countries. 相似文献
85.
86.
This article reviews the use of conventional disease-modifying antirheumatic drugs (DMARDs) in the treatment of early rheumatoid arthritis (RA). The Finnish early RA cohorts are used as examples of how early and active treatment strategies have improved over time with increasing variety of available DMARDs. Therapy goals of early RA include remission to prevent severe long-term outcomes of RA. Remission can be achieved in a third of patients with early RA using a combination of conventional DMARDs, including methotrexate, sulfasalazine, hydroxychloroquine, and prednisolone. Of patients with early RA, 20% to 30% do not improve enough with conventional treatments and should be identified at early phases to consider institution of biologic agents. 相似文献
87.
88.
89.
Gabriel Courties Timo Heidt Matthew Sebas Yoshiko Iwamoto Derrick Jeon Jessica Truelove Benoit Tricot Greg Wojtkiewicz Partha Dutta Hendrik B. Sager Anna Borodovsky Tatiana Novobrantseva Boris Klebanov Kevin Fitzgerald Daniel G. Anderson Peter Libby Filip K. Swirski Ralph Weissleder Matthias Nahrendorf 《Journal of the American College of Cardiology》2014
90.
Waleed Brinjikji Patrick Nicholson Christopher A Hilditch Timo Krings Vitor Pereira Ronit Agid 《Neuroradiology》2020,62(4):417-425
Cerebrofacial venous metameric syndrome (CVMS) is a complex craniofacial vascular malformation disorder in which patients have a constellation of venous vascular malformations affecting soft tissues, bone, dura, and neural structures including the eye and brain. It is hypothesized that a somatic mutation responsible for the venous abnormalities occurred prior to migration of the neural crest cells, and because of this, facial, osseous, and cerebral involvement typically follows a segmental or “metameric” distribution. The most commonly recognized form of CVMS is Sturge-Weber syndrome. However, a wide spectrum of CVMS phenotypical presentations exist with various metameric distributions of slow-flow vascular lesions including facial venous vascular malformations, developmental venous anomalies, venous angiomas, cavernous malformations (cavernomas), dural sinus malformations, and maybe even vascular tumors such as cavernous hemangiomas. Awareness of the various manifestations as described herewith is important for treatment and screening purposes. 相似文献