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排序方式: 共有874条查询结果,搜索用时 31 毫秒
31.
Osorio E Aguilera FS Osorio R García-Godoy F Cabrerizo-Vilchez MA Toledano M 《Medicina oral, patologia oral y cirugia bucal》2012,17(5):e833-e840
Objectives: This paper aims to assess the effectiveness of 3D nanoroughness and 2D microroughness evaluations, by their correlation with contact angle measurements and shear bond strength test, in order to evaluate the effect of two different acids conditioning on the bonding efficacy of a leucite-based glass-ceramic to a composite resin. Study Design: Ceramic (IPS Empress) blocks were treated as follows: 1) no treatment, 2) 37% phosphoric acid (H3PO4), 15 s, 3) 9% hydrofluoric acid (HF), 5 min. Micro- and nano-roughness were assessed with a profilometer and by means of an atomic force microscopy (AFM). Water contact angle (CA) measurements were determined to assess wettability of the ceramic surfaces with the asixymetric drop shape analysis contact diameter technique. Shear bond strength (SBS) was tested to a resin composite (Z100) with three different adhesive systems (Scotchbond Multipurpose Plus, Clearfil New Bond, ProBOND). Scanning electron microscopy (SEM) images were performed. Results: nanoroughness values assesed in 50x50 μm areas showed differences between groups did not found by profilometer. HF treatment created the nano- roughest surfaces and the smallest CA (p<0.05), producing the highest SBS to the composite resin with all tested adhesive systems (p<0.05). No differences existed between the SBS produced by the adhesive systems evaluated with any of the surface treatments tested. Conclusions: Nano-roughness obtained in a 50x50 μm scan size areas was the most reliable data to evaluate the topographical changes produced by the different acid treatments on ceramic surfaces. 相似文献
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34.
Jae-Young Hong Seung-Woo Suh Easwar TR Suk Joo Hong Yong-Chul Yoon Hyung-Jin Kang 《The spine journal》2013,13(11):1510-1520
Background contextFew accurate analyses of clinically useful vertebral anatomy have been conducted, and most have focused on thoracic idiopathic scoliosis.PurposeTo evaluate the different anatomic characteristics in scoliosis by disease type and level.Study designObservational cohort study.Patient sampleForty-eight patients with scoliosis were included in this study.Outcome measuresSubjects underwent computed tomography (CT) of the whole spine.MethodsForty-eight patients with scoliosis were included in this study: 15 adolescent idiopathic, 11 cerebral palsy (CP), 10 muscular dystrophy (MD), and 12 congenital (CG) scoliosis patients with similar demographics. Subjects underwent CT of the whole spine, preoperatively. Eight anatomic parameters were measured in multiplanar reconstructive CT images, and statistical analysis was performed to investigate differences.ResultsIn general, values in the anatomic parameters were similar for the four diseases. Each parameter showed the unique change pattern according to the spinal level regardless of curvature shape, direction, or magnitude. In particular, chord length (CL) in MD and CG scoliosis was lower than in adolescent idiopathic scoliosis (AIS) and CP, and pedicle rib unit length was lower in CG scoliosis than in the other diseases (p<.05). Comparisons of convex and concave anatomies in AIS showed that inner pedicle width (PWI) and outer pedicle width (PWO) were wider for convex side, CL, pedicle width, and transverse pedicle angle were greater for concave side (p<.05), and differences were more significant at apices. However, in CP, PWI and PWO were similar between convex and concaves sides (p>.05). Although PWI and PWO were wider for convex sides and CL and pedicle length were greater for concave sides in MD (p<.05), differences were less significant at apices. Particularly, CG scoliosis showed severely deformed anatomy, with differences of seven parameters at apical vertebrae (p<.05).ConclusionClinical anatomies of vertebrae in scoliosis were found to differ significantly at different levels and in terms of convexity and disease type. 相似文献
35.
Giant panda (Ailuropoda melanoleuca) sperm morphometry and function after repeated freezing and thawing
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J. Santiago‐Moreno M. C. Esteso J. Pradiee C. Castaño A. Toledano‐Díaz E. O'Brien A. Lopez‐Sebastián E. Martínez‐Nevado M. Delclaux J. Fernández‐Morán Z. Zhihe 《Andrologia》2016,48(4):470-474
This work examines the effects of subsequent cycles of freezing–thawing on giant panda (Ailuropoda melanoleuca) sperm morphometry and function, and assesses whether density‐gradient centrifugation (DGC) can increase the number of freezing–thawing cycles this sperm can withstand. A sperm sample was collected by electroejaculation from a mature giant panda and subjected to five freezing–thawing cycles. Although repeated freezing–thawing negatively affected (P < 0.05) sperm motility and membrane integrity, in both nonselected and DCG‐selected sperm samples, >60% of the sperm cells in both treatments showed acrosome integrity even after the fifth freezing cycle. In fresh semen, the sperm head length was 4.7 μm, the head width 3.6 μm, area 14.3 μm2 and perimeter length 14.1 μm. The present results suggest that giant panda sperm trends to be resistant to repeated freezing–thawing, even without DGC selection. 相似文献
36.
Papacchini F Toledano M Monticelli F Osorio R Radovic I Polimeni A García-Godoy F Ferrari M 《European journal of oral sciences》2007,115(5):417-424
The hydrolytic stability of composite repairs is a desirable property. In the present study, the composite repair microtensile bond strength, failure mode distribution, and nanoleakage occurrence before and after thermocycling were evaluated. Standardized, 1-month-old composite substrates were roughened, cleaned, and randomly assigned to seven groups according to the intermediate agent applied. Resin-based, silane-based, and combined silane/adhesive coupling agents were investigated. The same resin composite as the substrate was used for repair. For each group, repaired samples were wet stored for 24 h (37 degrees C) or thermocycled (5,000 cycles, 5-55 degrees C). Failure mode and silver nitrate penetration were examined by stereomicroscopy. Intermediate agent, experimental condition, and their interaction were significant factors. Hydrophobic flowable composites resulted in statistically higher repair strengths, lower occurrence of adhesive failures, and good quality interfacial coupling without any silver uptake in both conditions. Light-curing, hydrophilic resin monomer-based intermediate agents, although not affected by thermocycling, showed a more pronounced silver penetration. The composite repair strength of a self-curing silane/adhesive agent was significantly affected by thermal stresses, despite the absence of silver uptake. A prehydrolized silane agent recorded the lowest repair strength, with minimal or no evidence of interfacial silver impregnation after thermocycling. In conclusion, flowability and hydrophobic nature can be considered important properties when selecting intermediate agents for composite repair. 相似文献
37.
The same target sequences are differentially important for activation of the interleukin 2 receptor alpha-chain gene in two distinct T-cell lines. 总被引:7,自引:1,他引:7
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MS Krishna Kumar Sankarram Renganathan Clement J Joseph TR Easwar David V Rajan 《Indian Journal of Orthopaedics》2014,48(5):501-505
Background:
Medial patellofemoral ligament (MPFL) is one of the major static medial stabilising structures of the patella. MPFL is most often damaged in patients with patellar instability. Reconstruction of MPFL is becoming a common surgical procedure in treating patellar instability. We hypothesised that MPFL reconstruction was adequate to treat patients with patellar instability if the tibial tubercle and the centre of the trochlear groove (TT-TG) value was less than 20 mm and without a dysplastic trochlea.Materials and Methods:
30 patients matching our inclusion criteria and operated between April 2009 and May 2011 were included in the study. MPFL reconstruction was performed using gracilis tendon fixed with endobutton on the patellar side and bio absorbable interference screw or staple on the femoral side. Patients were followed up with subjective criteria, Kujala score and Lysholm score.Results:
The mean duration of followup was 25 months (range 14-38 months). The mean preoperative Kujala score was 47.5 and Lysholm score was 44.7. The mean postoperative Kujala score was 87 and Lysholm score was 88.06. None of the patients had redislocation.Conclusion:
MPFL reconstruction using gracilis tendon gives excellent results in patients with patellar instability with no redislocations. Some patients may have persistence of apprehension. 相似文献39.
Sharat Damodar Prashantha Bhat Praveen Kumar Rajesh TR Ratan Gupta 《Indian journal of hematology & blood transfusion》2014,30(1):64-67
Acute leukemia, secondary myelodysplasia and paroxysmal nocturnal hemoglobinuria evolving from severe aplastic anemia (AA) following immunosuppressive therapy are well recognized. However, severe AA occurring after complete remission of acute promyelocytic leukemia (APL) has been documented only once in 2009. We report a case of 30-year-old male diagnosed with APL who achieved complete cytogenetic remission with all-trans retinoic acid based induction regimen and developed severe AA few months later during maintenance therapy. 相似文献
40.
Manuel Toledano Fátima S. Aguilera Salvatore Sauro Inmaculada Cabello Estrella Osorio Raquel Osorio 《Dental materials》2014