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This study investigated the effect of irradiation with an erbium‐doped yttrium aluminium garnet (Er:YAG) laser and coating with silica on the surface characteristics, bond strength, and flexural strength of dental zirconia. Three hundred and forty‐three standard zirconia specimens were created, and 49 were assigned to each of seven surface treatment groups: (i) no treatment; Er:YAG laser (80 mJ/2 Hz) with pulse widths of 50 μs (ii), 100 μs (iii), 300 μs (iv), or 600 μs (v); or tribochemical silica coating at the partially sintered stage (vi) or after sintering was complete (vii). All specimens were sintered after the surface treatments, except for the group in which specimens were sintered before treatment. The study outcomes were roughness, surface loss, microshear bond strength (μSBS), and biaxial flexural strength (BFS). Mean roughness and surface loss values were significantly higher in specimens from irradiated groups than in those from silica‐coated groups. Regarding μSBS, after aging, specimens from all experimental groups presented very low and similar μSBS values, irrespective of the surface treatment. Silica coating after sintering yielded the highest BFS (1149.5 ± 167.6 MPa), while coating partially sintered specimens with silica resulted a BFS (826.9 ± 60.9 MPa) similar to that of the untreated control group (794.9 ± 101.7 MPa). Laser treatments, irrespective of pulse width used, significantly decreased the BFS. In the group treated with laser at 300 μs pulse width, specimens exhibited the lowest BFS value (514.1 ± 71.5 MPa). Adhesion to zirconia was not stable after aging, regardless of the surface treatment implemented.  相似文献   
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ObjectivesTo determine the prevalence of pneumococcal serotypes and antimicrobial susceptibility in patients with meningitis, and to evaluate the implications for vaccine coverage.MethodsPneumococcal strains obtained from normally sterile fluids from patients admitted with meningitis were isolated at the Hospital de Clínicas of the Universidade Federal de Uberlândia, Minas Gerais State, and sent to the Instituto Adolfo Lutz, city of São Paulo, São Paulo State, for further identification, serotyping, and antimicrobial susceptibility determination.ResultsFrom April 1999 to April 2009, 338 pneumococcal strains were isolated, and 72 obtained from patients with meningitis, were analyzed. Patients’ ages varied from one month to 82.2 years (mean of 18.4 ± 22.9 years; median of 5.2 years) and 46 (63.9%) patients were male. Strains were isolated from cerebrospinal fluid [66 occasions (91.7%)] and blood [6 occasions (8.3%)]. The most commonly identified serotypes were 14, 19F, 3, 7F, 6A, 6B, 10A, 18C, 23F, 5, and 34. Of the 20 [27.8%] oxacillin-resistant strains, 17 [23.6%] were resistant to penicillin and nine [12.5%] to ceftriaxone, both resistance patterns being more common in children aged two years or less and during the 2005–2009 period.ConclusionsResistance to penicillin and ceftriaxone was detected in 23.6% and 12.5% of the strains, respectively, and predominated in children aged two years or less and during the 2005–2009 period. There were 24 different serotypes of pneumococcus and 79.8% of the serotypes were represented in the 7-valent conjugated vaccine [PVC7].  相似文献   
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The ECGs of highly trained athletes reveal variants that may incorrectly be called abnormal.  相似文献   
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Abstract

African Americans experience higher morbidity and mortality than Whites do as a result of hypertension and associated cardiovascular disease. Chronic psychosocial stress has been considered an important contributing factor to these high rates. The authors describe the rationale and design for a planned randomized controlled trial comparing Transcendental Meditation, a stress-reduction technique, with lifestyle education in the treatment of hypertension and hypertensive heart disease in urban African Americans. They pretested 170 men and women aged 20 to 70 years over a 3-session baseline period, with posttests at 6 months. Outcomes included clinic and ambulatory blood pressure, quality of life, left ventricular mass measured by M-mode echocardiography, left ventricular diastolic function measured by Doppler, and carotid atherosclerosis measured by β-mode ultrasound. This trial was designed to evaluate the hypothesis that a selected stress reduction technique is effective in reducing hypertension and hypertensive heart disease in African Americans.  相似文献   
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BackgroundOutcomes of newly diagnosed multiple myeloma (NDMM) in developing regions have not paralleled those in developed settings. Economic disadvantage, comorbidities, and aggressive disease behavior play competing roles on defining outcomes. Our aim was to analyze the impact of socioeconomic characteristics and comorbidities on therapy initiation, drug selection, and survival outcomes of NDMM in a resource-constrained setting.Patients and MethodsThis retrospective single-center cohort included ≥ 18-year-old NDMM patients from January 2006 to December 2018.ResultsA total of 245 patients were included with a median age of 62 years, Eastern Cooperative Oncology Group performance status ≤ 2 in 70.2%, International Staging System score ≥ 2 in 89.4%, and high-risk disease in 31.6%. Comorbidities were reported in 69.4%, and Charlson comorbidity index (CCI) was ≥ 2 in 64.1%. A total of 87.4% (n = 214) received thalidomide-, alkylating-, and bortezomib-based induction in 67.8%, 18.2%, and 13.1%. Patient-related factors including performance status, comorbidities, and CCI, but not myeloma-related factors, were associated with a decreased likelihood of initiating induction therapy. On multivariate analysis, CCI ≥ 2 remained statistically significant (odds ratio, 5.81; P = .005). Overall survival was 44 months. Although both patient- and myeloma-related factors were associated with a decreased overall survival, only International Staging System score > 2 (hazard ratio, 3.53; P = .004) and induction without bortezomib-based regimens (hazard ratio, 4.45; P < .001) were statistically significant on multivariate analysis.ConclusionMyeloma- and treatment-related factors are the main determinants of survival in NDMM induction-eligible patients. Patient-related factors play a pivotal role determining access to therapy and survival outcomes. Comorbidity index and performance status were determinant on defining therapy initiation in this real-world population, which emphasizes the need to improve health baseline conditions in resource-constrained settings.  相似文献   
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We present a small child with febrile peaks and syncopal episodes secundary to ventricular tachycardia, in whom it was eventually possible to demostrate the Brugada Syndrome with a special presentation in the ECG; early repolarization pattern in lead I and a aVL and Brugada pattern during fever in V1‐V2. This is, to our knowledge, tha first case with this special ECG presentation in a small child.  相似文献   
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