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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
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Ayman A. Hussein David O. Martin Walid Saliba Deven Patel Saima Karim Omar Batal Mustafa Banna Michelle Williams-Andrews Minerva Sherman Mohamed Kanj Mandeep Bhargava Thomas Dresing Thomas Callahan Patrick Tchou Luigi Di Biase Salwa Beheiry Bruce Lindsay Andrea Natale Oussama Wazni 《Heart rhythm》2009,6(10):1425-1429
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997.
Bandar M. A. AL-Makramani BDS HDD MDSc Abdul A. A. Razak BDS MSc PhD & Mohamed I. Abu-Hassan BDS MDSc PhD 《Journal of prosthodontics》2009,18(6):484-488
Purpose: This study investigated the occlusal fracture resistance of Turkom-Cera-fused alumina compared to Procera AllCeram and In-Ceram all-ceramic restorations.
Materials and Methods: Six master dies were duplicated from the prepared maxillary first premolar tooth using nonprecious metal alloy (Wiron 99). Ten copings of 0.6 mm thickness were fabricated from each type of ceramic, for a total of thirty copings. Two master dies were used for each group, and each of them was used to lute five copings. All groups were cemented with resin luting cement Panavia F according to manufacturer's instructions and received a static load of 5 kg during cementation. After 24 hours of distilled water storage at 37°C, the copings were vertically compressed using a universal testing machine at a crosshead speed of 1 mm/min.
Results: The results of the present study showed the following mean loads at fracture: Turkom-Cera (2184 ± 164 N), In-Ceram (2042 ± 200 N), and Procera AllCeram (1954 ± 211 N). ANOVA and Scheffe's post hoc test showed that the mean load at fracture of Turkom-Cera was significantly different from Procera AllCeram ( p < 0.05). Scheffe's post hoc test showed no significant difference between the mean load at fracture of Turkom-Cera and In-Ceram or between the mean load at fracture of In-Ceram and Procera AllCeram.
Conclusion: Because Turkom-Cera demonstrated equal to or higher loads at fracture than currently accepted all-ceramic materials, it would seem to be acceptable for fabrication of anterior and posterior ceramic crowns. 相似文献
Materials and Methods: Six master dies were duplicated from the prepared maxillary first premolar tooth using nonprecious metal alloy (Wiron 99). Ten copings of 0.6 mm thickness were fabricated from each type of ceramic, for a total of thirty copings. Two master dies were used for each group, and each of them was used to lute five copings. All groups were cemented with resin luting cement Panavia F according to manufacturer's instructions and received a static load of 5 kg during cementation. After 24 hours of distilled water storage at 37°C, the copings were vertically compressed using a universal testing machine at a crosshead speed of 1 mm/min.
Results: The results of the present study showed the following mean loads at fracture: Turkom-Cera (2184 ± 164 N), In-Ceram (2042 ± 200 N), and Procera AllCeram (1954 ± 211 N). ANOVA and Scheffe's post hoc test showed that the mean load at fracture of Turkom-Cera was significantly different from Procera AllCeram ( p < 0.05). Scheffe's post hoc test showed no significant difference between the mean load at fracture of Turkom-Cera and In-Ceram or between the mean load at fracture of In-Ceram and Procera AllCeram.
Conclusion: Because Turkom-Cera demonstrated equal to or higher loads at fracture than currently accepted all-ceramic materials, it would seem to be acceptable for fabrication of anterior and posterior ceramic crowns. 相似文献
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999.
Alia Mohamed Atallah Mohamed E. Abou El-Ghar Mohamed A. Ghoneim 《Rheumatology international》2009,30(1):75-79
In a previous study, the musculoskeletal affections among kidney recipients (KR) were reported, with 63 KR suffering from joint affections. We sought to determine the prevalence of osteonecrosis (ON) among those KR with joint affections, its distribution among the affected joints, and possible risk predictors. KR were subjected to biochemical, haematological, and hepatitis serology estimations. Radiographic and magnetic resonance imaging were performed. Relevant data were retrieved from Patient Information System. Fourteen KR were suffering from ON, with an incidence of 22.2% in KR with joint affections and 12.0% in the target population of KR. The femoral head was affected in 57.1% and the femoral condyles in 28.6%. Hypocalcaemia was observed in KR with ON. Whether hypocalcaemia is a causative or associative of ON yet remains to be decided in forthcoming studies. 相似文献
1000.
Mariam Siala Nadia Mahfoudh Radhouane Gdoura Mohamed Younes Hela Fourati Arwa Kammoun Ilhem Chour Nihel Meddeb Lilia Gaddour Faiza Hakim Sofien Baklouti Naceur Bargaoui Sleheddine Sellami Adnene Hammami Hafedh Makni 《Rheumatology international》2009,29(10):1193-1196
The purpose of the present study is to investigate the frequency of HLA-B27 and its alleles in reactive arthritis (ReA) and in ankylosing spondylitis (AS) in Tunisia. HLA-B27 alleles were typed by PCR amplification with sequence-specific primers. We studied 17 patients with ReA associated with urethritis or with gastrointestinal infection; 42 HLA-B27-positive patients with AS and 100 healthy controls. Eleven ReA patients (67.7%) were HLA-B27 positive. There was an increased frequencies of HLA-B27 (P = 7.76 × 10−12, OR = 59.30) and a moderate increase of HLA-B51 (P = 0.015; OR = 4.91) alleles in ReA patients when compared with healthy controls. Four B27 subtypes were identified: B*2702, 05, 09 and B*2712. The distribution of these alleles in the ReA patients was 37.5% for B*2702 and B*2705. Only these two subtypes were detected in 18 (42.8%) and 24 (57.1%), respectively, of the AS patients. B*2709 and B*2712 were relatively rare in ReA patients and were identified in one case each. Our results showed a restricted number of HLA-B27 subtypes associated with ReA and AS. B*2702 and 2705 were common in ReA and AS patients. 相似文献