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排序方式: 共有471条查询结果,搜索用时 62 毫秒
1.
Modena Débora Aparecida Oliveira Miranda Ana Carolina Godoy Grecco Clovis Liebano Richard Eloin Cordeiro Raquel Cristina Tancsik Guidi Renata Michelini 《Lasers in medical science》2020,35(4):797-806
Lasers in Medical Science - Using light sources in phototherapy has presented promising results regarding several types of facial and body skin affections for centuries. The neodymium-doped yttrium... 相似文献
2.
Clovis Arcoverde Freitas-Neto Fernando Oréfice Rogerio A. Costa Juliana L. Oréfice Swetha Dhanireddy Armin Maghsoudlou 《Seminars in ophthalmology》2016,31(5):495-498
To describe how a multifocal fundus imaging system assisted the early diagnosis of cat scratch neuroretinitis in a case of a 27-year-old male with unilateral visual loss, neuroretinitis, and a peripapillary angiomatous lesion. Multimodal fundus imaging analysis was an essential contributor to the clinical diagnosis of cat scratch neuroretinitis during the early stage of the disease. 相似文献
3.
Baptiste Morel Pierre Bertault Géraldine Favrais Elsa Tavernier Barthelemy Tosello Nathalie Bednarek Laurent Barantin Alexandra Chadie Maia Proisy Yongchao Xu Isabelle Bloch Dominique Sirinelli Catherine Adamsbaum Clovis Tauber Elie Saliba 《Diagnostic and interventional imaging》2021,102(4):225-232
PurposeThe purpose of this study was to identify in the EPIRMEX cohort the correlations between MRI brain metrics, including diffuse excessive high signal intensities (DEHSI) obtained with an automated quantitative method and neurodevelopmental outcomes at 2 years.Materials and methodsA total of 390 very preterm infants (gestational age at birth ≤ 32 weeks) who underwent brain MRI at term equivalent age at 1.5T (n = 338) or 3T (n = 52) were prospectively included. Using a validated algorithm, automated metrics of the main brain surfaces (cortical and deep gray matter, white matter, cerebrospinal fluid) and DEHSI with three thresholds were obtained. Linear adjust regressions were performed to assess the correlation between brain metrics with the ages and stages questionnaire (ASQ) score at 2 years.ResultsBasal ganglia and thalami, cortex and white matter surfaces positively and significantly correlated with the global ASQ score. For all ASQ sub-domains, basal ganglia and thalami surfaces significantly correlated with the scores. DEHSI was present in 289 premature newborns (74%) without any correlation with the ASQ score. Metrics of DEHSI were greater at 3T than at 1.5T.ConclusionBrain MRI metrics obtained in our multicentric cohort correlate with the neurodevelopmental outcome at 2 years of age. The quantitative detection of DEHSI is not predictive of adverse outcomes. Our automated algorithm might easily provide useful predictive information in daily practice. 相似文献
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Fernando Tadeu Vasconcelos Amaral Paulo Henrique Manso André Schmidt Ricardo Nilson Sgarbieri Walter Villela de Andrade Vicente Clovis Carbone Junior Jane Somerville 《Brazilian Journal Of Cardiovascular Surgery》2015,30(3):373-379
During the last decades, advances in diagnosis and treatment of congenital heart
disease have allowed many individuals to reach adulthood. Due mainly to the great
diagnostic diversity and to the co-morbidities usually present in this age group,
these patients demand assistance in a multidisciplinary facility if an adequate
attention is aimed. In this paper we reviewed, based in the international literature
and also on the authors’ experience, the structural conditions that should be
available for these patients. We highlighted aspects like the facility
characteristics, the criteria usually adopted for patient transfer from the
paediatric setting, the composition of the medical and para- medical staff taking
into account the specific problems, and also the model of outpatient and in-hospital
assistance. We also emphasized the importance of patient data storage, the
fundamental necessity of institutional support and also the compromise to offer
professional training. The crucial relevance of clinical research is also approached,
particularly the development of multicenter studies as an appropriate methodology for
this heterogeneous patient population. 相似文献
6.
Miranda CB Pagani C Benetti AR Matuda Fda S 《Journal of applied oral science : revista FOB》2005,13(2):204-211
Since bleaching has become a popular procedure, the effect of peroxides on dental hard tissues is of great interest in research. Purpose: The aim of this in vitro study was to perform a qualitative analysis of the human enamel after the application of in-office bleaching agents, using Scanning Electron Microscopy (SEM). Materials and Methods: Twenty intact human third molars extracted for orthodontic reasons were randomly divided into four groups (n=5) treated as follows: G1- storage in artificial saliva (control group); G2- four 30-minute applications of 35% carbamide peroxide (total exposure: 2h); G3- four 2-hour exposures to 35% carbamide peroxide (total exposure: 8h); G4- two applications of 35% hydrogen peroxide, which was light-activated with halogen lamp at 700mW/cm2 during 7min and remained in contact with enamel for 20min (total exposure: 40min). All bleaching treatments adopted in this study followed the application protocols advised by manufacturers. Evaluation of groups submitted to 35% carbamide peroxide was carried out after two time intervals (30 minutes and 2 hours per session), following the extreme situations recommended by the manufacturer. Specimens were prepared for SEM analysis performing gold sputter coating under vacuum and were examined using 15kV at 500x and 2000x magnification. Results: Morphological alterations on the enamel surface were similarly detected after bleaching with either 35% carbamide peroxide or 35% hydrogen peroxide. Surface porosities were characteristic of an erosive process that took place on human enamel. Depression areas, including the formation of craters, and exposure of enamel rods could also be detected. Conclusion: Bleaching effects on enamel morphology were randomly distributed throughout enamel surface and various degrees of enamel damage could be noticed. Clinical significance: In-office bleaching materials may adversely affect enamel morphology and therefore should be used with caution. 相似文献
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8.
Influence of resin composite shade and location of the gingival margin on the microleakage of posterior restorations 总被引:2,自引:0,他引:2
OBJECTIVE: The objective of this in vitro study was to evaluate the influence of resin composite shade and location of the gingival margin (enamel or dentin) on the microleakage of proximal restorations on posterior teeth. Methods and MATERIALS: Sixty freshly extracted human third molars were prepared with standardized Class II box-shaped cavities with proportional size and shape, with distal gingival margins located on the enamel and mesial gingival margins on dentin. The teeth were randomly divided into 6 groups according to resin shade (n=10): G1-Incisal; G2-A1; G3-A2; G4-A3; G5-A3.5; G6-A4. The cavities were restored with a total-etch 1-bottle adhesive system and microhybrid resin composites inserted in 4 increments, light cured for 20 seconds through the occlusal surface, then an additional 60 seconds for each surface. After 1 week of immersion in distilled water, the specimens were thermocycled (500 cycles, 5 degrees -55 degrees C, 30 seconds dwell time), sealed with nail polish and immersed in 0.5% basic fuschin solution for 24 hours. The restorations were sectioned longitudinally, and microleakage was evaluated using a 0-3 score scale. RESULTS: Data were subjected to Kruskal-Wallis and Wilcoxon tests at p<0.05. No statistically significant differences between groups were observed regarding the shade of resin composite (p=0.8570). When margins (enamel or dentin) were considered separately, statistically significant differences were observed between groups (p<0.0001), with enamel margins exhibiting lower degrees of microleakage. CONCLUSION: The variation of resin composite shades utilized in this study did not influence the microleakage of Class II restorations. However, the location of the gingival margin influenced the microleakage. 相似文献
9.
Bernardes RA de Moraes IG Garcia RB Bernardineli N Baldi JV Victorino FR Vasconcelos BC Duarte MA Bramante CM 《Journal of endodontics》2007,33(4):484-487
This study evaluated the time, occurrence of fracture, and quality of apical cavity preparation with three different ultrasonic diamond tips: Satelec, Trinity, and a new type, CVD (chemical vapor deposition), using scanning electron microscopy (SEM) analysis. Thirty human single-rooted premolars were selected, submitted to apicectomy, and prepared with ultrasonic tips; impressions were then obtained. The presence of fractures was evaluated on the impressions, and the quality of preparation was evaluated by SEM analysis of teeth and scoring by two examiners. The group prepared with the CVD tips exhibited the shorter preparation time and did not present fractures. There was no statistically significant difference in the quality of preparation for the three tips. The three brands of ultrasonic tips produced adequate grinding without altering the morphology of the apical foramen. 相似文献
10.
This study compared the shear bond strength (SBS) to enamel of five self-etching primer/adhesive systems and one total-etch, one-bottle adhesive system. Sixty freshly extracted bovine incisors were mounted, polished to 600-grit and randomly assigned to six groups (n=10): Adper Prompt Self-Etch (AD), OptiBond Solo Plus Self-Etch (OP), AdheSE (AS), Tyrian (TY) and Clearfil SE Bond (SE) as self-etching systems; and Single Bond (SB) as a total-etch system (control). The respective hybrid composite was applied in a #5 gelatin capsule and light-cured. After 500 thermal cycles (5 degrees C-55 degrees C), the specimens were loaded in shear using an Instron at 5 mm/minute. Mean bond strengths were analyzed with one-way ANOVA, followed by a Duncan's post-hoc test (p 0.05). SBS (mean +/- SD) were: AD=13.0(+/- 2.5); OP=5.6(+/-2.3);AS=12.6(+/-3.7); TY=7.6(+/-2.6); SE=17.6(+/-4.5) and SB=17.9(+/-4.4). ANOVA showed a significant difference at p<0.0001. Duncan's post-hoc test ranked this difference in three homogeneous subsets. Only SE showed similar enamel SBS compared to the total-etch system tested (SB). AD and AS were ranked in the intermediary Duncan's subset, while TY and OP resulted in the lowest SBS. SBS to enamel with self-etching primers may depend on its specific composition. 相似文献