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Objective

To determine whether stratification of complexity models in congenital heart surgery (RACHS-1, Aristotle basic score and STS-EACTS mortality score) fit to our center and determine the best method of discriminating hospital mortality.

Methods

Surgical procedures in congenital heart diseases in patients under 18 years of age were allocated to the categories proposed by the stratification of complexity methods currently available. The outcome hospital mortality was calculated for each category from the three models. Statistical analysis was performed to verify whether the categories presented different mortalities. The discriminatory ability of the models was determined by calculating the area under the ROC curve and a comparison between the curves of the three models was performed.

Results

360 patients were allocated according to the three methods. There was a statistically significant difference between the mortality categories: RACHS-1 (1) - 1.3%, (2) - 11.4%, (3)-27.3%, (4) - 50 %, (P<0.001); Aristotle basic score (1) - 1.1%, (2) - 12.2%, (3) - 34%, (4) - 64.7%, (P<0.001); and STS-EACTS mortality score (1) - 5.5 %, (2) - 13.6%, (3) - 18.7%, (4) - 35.8%, (P<0.001). The three models had similar accuracy by calculating the area under the ROC curve: RACHS-1- 0.738; STS-EACTS-0.739; Aristotle- 0.766.

Conclusion

The three models of stratification of complexity currently available in the literature are useful with different mortalities between the proposed categories with similar discriminatory capacity for hospital mortality.  相似文献   
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Gastric cancer is an aggressive disease often diagnosed at an advanced stage. Despite improvements in surgical and adjuvant treatment approaches, gastric cancer remains a global public health problem with a 5-year overall survival of less than 25 %. This is a heterogeneous disease, both in terms of biology and genetics, and many prognostic biomarkers have been pointed out in the literature; nevertheless, their application remains debatable. In this review, we opted to give relevance to those biomarkers that have been the subject of studies with significant statistical power, which have been replicated and have been/are in targeted therapy clinical trials and, which as a consequence, have their prognostic and/or predictive value established. Some gastric cancer biomarkers that may help in defining the course of treatment are also discussed. Accepted practical guidelines, wet-lab protocols for the detection of these biomarkers, as well as ongoing and completed clinical trials have been compiled. In summary, clinical approaches based on the combination of correct staging with targeted and conventional systemic therapies may improve gastric cancer patients’ outcome, but are only in their infancy. Some major challenges in identifying reliable prognostic/predictive biomarkers are individual genetic variation and tumour heterogeneity that often influence response to therapy and drug resistance. Prognostic and predictive biomarkers may nevertheless be extremely valuable to correctly stratify gastric cancer patients for treatment and, ultimately, improve survival.  相似文献   
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Purpose: This study aimed to evaluate stress distribution on peri‐implant bone simulating the influence of platform switching in external and internal hexagon implants using three‐dimensional finite element analysis. Materials and Methods: Four mathematical models of a central incisor supported by an implant were created: External Regular model (ER) with 5.0 mm × 11.5 mm external hexagon implant and 5.0 mm abutment (0% abutment shifting), Internal Regular model (IR) with 4.5 mm × 11.5 mm internal hexagon implant and 4.5 mm abutment (0% abutment shifting), External Switching model (ES) with 5.0 mm × 11.5 mm external hexagon implant and 4.1 mm abutment (18% abutment shifting), and Internal Switching model (IS) with 4.5 mm × 11.5 mm internal hexagon implant and 3.8 mm abutment (15% abutment shifting). The models were created by SolidWorks software. The numerical analysis was performed using ANSYS Workbench. Oblique forces (100 N) were applied to the palatal surface of the central incisor. The maximum (σmax) and minimum (σmin) principal stress, equivalent von Mises stress (σvM), and maximum principal elastic strain (εmax) values were evaluated for the cortical and trabecular bone. Results: For cortical bone, the highest stress values (σmax and σvm) (MPa) were observed in IR (87.4 and 82.3), followed by IS (83.3 and 72.4), ER (82 and 65.1), and ES (56.7 and 51.6). For εmax, IR showed the highest stress (5.46e‐003), followed by IS (5.23e‐003), ER (5.22e‐003), and ES (3.67e‐003). For the trabecular bone, the highest stress values (σmax) (MPa) were observed in ER (12.5), followed by IS (12), ES (11.9), and IR (4.95). For σvM, the highest stress values (MPa) were observed in IS (9.65), followed by ER (9.3), ES (8.61), and IR (5.62). For εmax, ER showed the highest stress (5.5e‐003), followed by ES (5.43e‐003), IS (3.75e‐003), and IR (3.15e‐003). Conclusion: The influence of platform switching was more evident for cortical bone than for trabecular bone, mainly for the external hexagon implants. In addition, the external hexagon implants showed less stress concentration in the regular and switching platforms in comparison to the internal hexagon implants.  相似文献   
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This study evaluated the effects of different parameters of dentin irradiation with erbium-doped yttrium aluminum garnet (Er:YAG) laser on bond strength to dentin and analyzed the ultramorphological characteristics of resin–laser-irradiated dentin interfaces using a transmission electron microscope (TEM). Dentin surfaces were abraded with SiC paper (600 grit) or Er:YAG laser-irradiated (120/4, 140/6, 180/4, or 200/6 mJ/Hz). Three adhesive systems were tested: Single Bond Plus (3M ESPE), Clearfil Protect Bond (Kuraray Med.), and Clearfil Tri-S Bond (Kuraray Med.). Treatments were performed over flat dentin surfaces of human third molars. Specimens were stored in distilled water for 1 week or 6 months and prepared for a microtensile bond strength test and interfacial ultrastructure for analysis. Microtensile bond strength data (n?=?5) were analyzed with three-way analysis of variance. Irradiation with Er:YAG laser did not reduce the bond strength values for self-etching adhesives even after 6 months of water storage. The hybrid layer formation was observed only when the adhesives were applied to non-irradiated dentin (control group). Nanoleakage occurred in all resin–dentin interfaces using Single Bond Plus for both periods. Nanoleakage pattern and bond strength of self-etching adhesives to dentin were less affected by Er:YAG laser irradiation and by the 6-month storage in water than was those of the etch-and-rinse adhesive. TEM analysis revealed no hybridization when dentin was laser-irradiated. Clinical significance: Minimally invasive caries removal has been proposed. Nevertheless, bonding mechanisms to lased dentin are not entirely described. Knowing the interaction between the treated dentin and bonding agents and its behavior over time is of utmost importance for new technologies. Regarding that, two-bottle self-etching adhesive system provided a more consistent evidence of its better behavior when bonding to lased substrate.  相似文献   
18.
Testicular vasculitis is a very rare extra-articular manifestation of rheumatoid arthritis (RA). We describe the case of a 53-year-old man diagnosed with RA for eight years, who was poorly controlled and developed rheumatoid vasculitis, which manifested as leg ulcers and peripheral polyneuropathy. The patient also had acute neutrophilic meningitis and was treated with antibiotics and intravenous pulse therapy with methylprednisolone (500 mg daily) for three days, followed by oral cyclophosphamide (2 mg/kg daily) and prednisone. Overall improvement was observed, and the patient was discharged. But 15 days later, the meningitis recurred, and the patient was readmitted and treated again with antibiotics. Three days later, he developed pain and enlargement of his left testicle with gangrene. Unilateral orchiectomy was performed, revealing lymphocytic vasculitis. The patient died two days later due to aspiration pneumonia. This case illustrates a rare and severe manifestation of rheumatoid vasculitis.  相似文献   
19.
Our aim was to evaluate cephalometrically the preoperative inclination of the incisors in a group of 50 patients with Class III dentofacial deformities whose immediate preoperative lateral cephalometric radiographs were analysed after they had been treated by maxillary advancement. The radiographs were hand-traced by the same operator who made the cephalometric analysis. Mean values for each measurement were compared with the normal values using Student's t-test (p<0.05). Results showed significantly increased inclination of the upper incisors, with a mean U1-NA angle of 27.58° and a mean U1-PP angle of 116°. The lower incisors were also inclined lingually, with a mean L1-NB angle of 22.53° and a mean IMPA of 83.13°. Thirty-five of the patients had labial inclination of the upper, and 28 lingual inclination of the lower, incisors. Mean inclinations of upper and lower incisors differed from the normal values, and the inclination of the lower incisors was more likely to be decompensated than that of the upper incisors.  相似文献   
20.
Lasers in Medical Science - Photobiomodulation with low-level laser therapy (PBM-LLLT) has been introduced as a new tool to relieve nipple pain and repair nipple damage in breastfeeding women;...  相似文献   
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