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11.
Anna-Maria Lutz Rüdiger Hampe Malgorzata Roos Nina Lümkemann Marlis Eichberger Bogna Stawarczyk 《The Journal of prosthetic dentistry》2019,121(1):166-172
Statement of problem
Polymeric material for 3-dimensional printing can be used to fabricate occlusal devices. However, information about fracture resistance and wear is scarce.Purpose
The purpose of this in vitro study was to investigate the fracture resistance and 2-body wear of 3-dimensional–printed (3DP) (FotoDent splint; Dreve Dentamid GmbH), milled polymethylmethacrylate (CAM) (Temp Basic; Transpa 95H16, Zirkonzahn GmbH), and conventionally fabricated polymethylmethacrylate (CAST) (Castdon; Dreve Dentamid GmbH) occlusal devices.Material and Methods
A total of 96 occlusal devices were prepared according to the 3 different manufacturing techniques 3DP, CAM, and CAST (n=32). For each manufacturing technique, specimens were further divided into initial fracture resistance tests (n=16) and artificial aging in the mastication simulator (50 N, 37°C) with 2-body wear followed by fracture resistance tests (n=16). The fracture resistance was determined using a universal testing machine (1 mm/min). The wear was measured after 20?000 and 120?000 mastication cycles with the replica technique, mapped with a laser scanner, and quantified in R software. Data were analyzed using a 2-way ANOVA followed by a 1-way ANOVA with Scheffé or Games-Howell post hoc tests, repeated measures ANOVA with corrected Greenhouse-Geisser P values, and the Levene, Mann-Whitney, and paired t tests (α=.05).Results
CAM presented higher initial fracture resistance than 3DP or CAST (P<.001). After mastication simulation, CAM followed by 3DP showed higher fracture resistance than CAST (P<.001). Mastication simulation decreased the fracture resistance for CAM and CAST (P<.001) but not for 3DP (P=.78). Three-dimensional–printed occlusal devices showed the highest material volume loss, followed by CAM and the lowest in CAST (P<.001).Conclusions
Three-dimensional–printed occlusal devices showed lower wear resistance and lower fracture resistance than those milled or conventionally fabricated. Therefore, only short-term application in the mouth is recommended. Further developments of occlusal device material for 3-dimensional printing are necessary. 相似文献12.
P. Mendogni S. Henchi L.C. Morlacchi D. Tosi M. Nosotti P. Tarsia A.I. Gregorini L. Rosso 《Transplantation proceedings》2019,51(1):194-197
Background
Solid organ transplantation is associated with a higher risk of Epstein-Barr virus (EBV)–related lymphoproliferative disease due to immunosuppressive regimen. Little evidence is currently available on post-transplant lymphoproliferative disorders (PTLDs) in the lung transplant (LuTx) setting, particularly in cystic fibrosis (CF) recipients.Methods
We retrospectively analyzed all the cases of PTLDs that occurred in our LuTx center between January 2015 and December 2017. We reviewed clinical and radiologic data, donor and recipient EBV serostatus, immunosuppressive therapy, histologic data, and follow-up of these patients.Results
A total of 77 LuTxs were performed at our center in the study period; 39 (50.6%) patients had CF; 4 developed EBV-related PTLDs. They were all young (17–26 years) CF patients with high serum EBV DNA load. Disease onset was within the first 3 months after LuTx. In 3 cases presentation was associated with fever and infection-like symptoms, whereas in 1 case radiologic suspicion arose unexpectedly from a CT scan performed for different clinical reasons. Diagnosis was reached through lung biopsy in all cases. All patients received rituximab,?cyclophosphamide, doxorubicin hydrochloride (hydroxydaunomycin), vincristine sulfate (Oncovin), and prednisone with variable response and complications.Conclusion
In our experience, the early development of EBV-related PTLD was a highly aggressive, life-threatening condition, which exclusively affected young CF patients in the early post-transplant period. The rate of this complication was relatively high in our population.Diagnosis with lung biopsy is crucial in all suspected cases and regular monitoring of EBV DNA levels is of utmost importance given the high correlation with PTLDs in patients at increased risk. 相似文献13.
Andreu Porta-Sánchez Andrew C.T. Ha Xuesong Wang Fahad Almehmadi Peter C. Austin Hadas D. Fischer Atif Al-Qubbany Diego Chemello Vijay Chauhan Eugene Downar Douglas S. Lee Kumaraswamy Nanthakumar 《The Canadian journal of cardiology》2019,35(2):169-177
Background
Catheter ablation of ventricular tachycardia (VT) can reduce the burden of ventricular arrhythmia (VA) but its effect on health care utilization and costs after such therapy is poorly known. We sought to compare the rates of cardiovascular (CV)-related hospitalizations, survival, and health care costs in patients with recurrent VT treated either with VT ablation or with medical therapy.Methods
One-hundred implantable cardioverter-defibrillator patients with structural heart disease who underwent VT ablation were included. Propensity score-matched patients with recurrent VT treated with medical therapy were identified from a prospective registry of approximately 7000 de novo implantable cardioverter-defibrillator patients. Outcomes and costs were ascertained using health administrative databases.Results
Among patients who underwent VT ablation, the cumulative rates of VA-related hospitalizations were lower in the 2 years after their ablation procedure compared with the year before (rate ratio, 0.3; 95% confidence interval [CI], 0.22-0.43). Rates of CV-related hospitalization and hospitalization because of VA post index date were similar between the VT ablation and medical therapy groups (hazard ratio [HR], 0.94; 95% CI, 0.57-1.54 and HR, 1.04; 95% CI, 0.57-1.91, respectively). Health care costs in the VT ablation patients were not increased post-ablation compared with the medical management group. The risk of all-cause mortality was lower among patients in the VT ablation group relative to the medical therapy group (HR, 0.64; 95% CI, 0.4-0.99).Conclusions
Patients who underwent VT ablation experienced a significant reduction in their rate of VA-related hospitalizations. Patients treated with VT ablation had similar rates of CV-related hospitalization compared with those treated with medical therapy without increased health care-related costs. 相似文献14.
《Clinical neurophysiology》2021,132(10):2639-2653
ObjectiveThis study brought together over 60 transcranial magnetic stimulation (TMS) researchers to create the largest known sample of individual participant single and paired-pulse TMS data to date, enabling a more comprehensive evaluation of factors driving response variability.MethodsAuthors of previously published studies were contacted and asked to share deidentified individual TMS data. Mixed-effects regression investigated a range of individual and study level variables for their contribution to variability in response to single and paired-pulse TMS data.Results687 healthy participant’s data were pooled across 35 studies. Target muscle, pulse waveform, neuronavigation use, and TMS machine significantly predicted an individual’s single-pulse TMS amplitude. Baseline motor evoked potential amplitude, motor cortex hemisphere, and motor threshold (MT) significantly predicted short-interval intracortical inhibition response. Baseline motor evoked potential amplitude, test stimulus intensity, interstimulus interval, and MT significantly predicted intracortical facilitation response. Age, hemisphere, and TMS machine significantly predicted MT.ConclusionsThis large-scale analysis has identified a number of factors influencing participants’ responses to single and paired-pulse TMS. We provide specific recommendations to minimise interindividual variability in single and paired-pulse TMS data.SignificanceThis study has used large-scale analyses to give clarity to factors driving variance in TMS data. We hope that this ongoing collaborative approach will increase standardisation of methods and thus the utility of single and paired-pulse TMS. 相似文献
15.
Elizabeth D. Krebs William Z. Chancellor Jared P. Beller J. Hunter Mehaffey Robert B. Hawkins Robert G. Sawyer Leora T. Yarboro Gorav Ailawadi Nicholas R. Teman 《The Annals of thoracic surgery》2021,111(2):594-599
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16.
Kristen E. Rhodin Vignesh Raman Oliver K. Jawitz Soraya L. Voigt Norma E. Farrow David H. Harpole Betty C. Tong Thomas A. D’Amico 《The Annals of thoracic surgery》2021,111(2):440-447
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17.
The mesopancreas does not have well-defined boundaries but is continuous and connected through its components with the paraaortic area. The mesopancreatic resection margin has been indicated as the primary site for R1 resection after PD in pancreatic head cancer and total mesopancreas excision has been proposed to achieve adequate retropancreatic margin clearance and to minimize the likelihood of R1 resection. However, the anatomy of the mesopancreas requires extended dissection of the paraaortic area to maximize posterior clearance. The artery-first surgical approach has been developed to increase local radicality at the mesopancreatic resection margin. During PD, the artery-first approach begins with dissection of the connective tissues around the SMA. However, the concept of the mesopancreas as a boundless structure that includes circumferential tissues around the SMA, SMV, and paraaortic tissue highlights the need to shift from artery-first PD to mesopancreas-first PD to reduce the risk of R1 resection. From this perspective the “artery-first” approach, which allows for the avoidance of R2 resection risk, should be integrated into the “mesopancreas-first” approach to improve the R0 resection rate.In total mesopancreas excision and mesopancreas-first pancreaticoduodenectomies, the inclusion of the paraaortic area and circumferential area around the SMA in the resection field is necessary to control the tumour spread along the mesopancreatic resection margin rather than to control or stage the spread in the nodal basin. 相似文献
18.
D. Adkins J. Ley P. Oppelt H.A. Gay M. Daly R.C. Paniello R. Jackson P. Pipkorn J. Rich J. Zevallos K. Trinkaus W. Thorstad 《Clinical oncology (Royal College of Radiologists (Great Britain))》2019,31(9):e123-e131
AimsOrgan preservation, an important goal in the treatment of head and neck squamous cell carcinoma (HNSCC), may include induction chemotherapy and cisplatin with radiation therapy (CRT). To our knowledge, no reports have directly compared the impact of induction chemotherapy with that of CRT on health-related quality of life (HRQOL).Materials and methodsIn a phase II trial, we assessed the HRQOL of patients treated with induction chemotherapy followed by CRT. Eligible patients had stage III–IV HNSCC. HRQOL questionnaires were administered at baseline, the end of induction (EOI), the end of CRT (EOCRT) and after CRT. Functional Assessment of Cancer Therapy (FACT version 4) assessed HRQOL. We carried out a comparison of changes in HRQOL from baseline to EOI and from EOI to EOCRT. This trial is registered with ClinicalTrials.gov (NCT01566435).ResultsThirty patients were enrolled in the study. Most HRQOL questionnaires were completed (88%). The mean total FACT scores did not differ from baseline to EOI (general: 83.8 versus 79.1, P = 0.08; head and neck: 109.7 versus 105.8, P = 0.33; Total Outcome Index: 69.7 versus 62.3, P = 0.03; respectively, using P ≤ 0.01 to adjust for multiple simultaneous tests of differences). However, total FACT scores significantly worsened from EOI to EOCRT (79.1 versus 62.3, P = 0.01; 105.8 versus 74.2, P < 0.01; 62.3 versus 34.2, P = 0.01; respectively). Within domains, the head and neck cancer subscale score did not differ from baseline to EOI (median 28.5 versus 27.0, P = 0.69), but significantly worsened from EOI to EOCRT (27.0 versus 9.5, P < 0.01). Swallowing, oral pain and voice quality improved from baseline to EOI, but worsened from EOI to EOCRT. Physical and functional scores worsened from baseline to EOI and from EOI to EOCRT. The emotional well-being score improved from baseline to EOI but worsened from EOI to EOCRT.ConclusionsOverall, HRQOL did not significantly change from baseline to EOI but dramatically worsened from EOI to EOCRT. 相似文献
19.
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