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91.
An inevitable loss of soft and hard tissue after tooth extraction often results in a compromised site for anterior implant esthetics in both vertical and horizontal dimensions. Immediate implant placement and provisionalization has been a viable option for replacing failing maxillary anterior teeth as it preserves the vertical existing osseous and gingival architecture. With the simultaneous addition of soft‐ and hard‐tissue grafts, the peri‐implant horizontal tissue topography can also be maintained. The esthetic success of immediate implant placement and provisionalization procedures is influenced by a number of factors that can be identified as patient‐dependent or clinician‐dependent. This article describes in detail the process of patient selection, indications, contraindications, diagnosis, treatment planning and treatment execution required to achieve functional and esthetic success with immediate implant placement and provisionalization.  相似文献   
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Background Glutamine (Gln) is an abundant nutrient used by cancer cells. Breast cancers cells and particularly triple-receptor negative breast cancer (TNBC) are reported to be dependent on Gln to produce the energy required for survival and proliferation. Despite intense research on the role of the intracellular Gln pathway, few reports have focussed on Gln transporters in breast cancer and TNBC.Methods The role and localisation of the Gln transporter SLC38A2/SNAT2 in response to Gln deprivation or pharmacological stresses was examined in a panel of breast cancer cell lines. Subsequently, the effect of SLC38A2 knockdown in Gln-sensitive cell lines was analysed. The prognostic value of SLC38A2 in a cohort of breast cancer was determined by immunohistochemistry.Results SLC38A2 was identified as a strongly expressed amino acid transporter in six breast cancer cell lines. We confirmed an autophagic route of degradation for SLC38A2. SLC38A2 knockdown decreased Gln consumption, inhibited cell growth, induced autophagy and led to ROS production in a subgroup of Gln-sensitive cell lines. High expression of SLC38A2 protein was associated with poor breast cancer specific survival in a large cohort of patients (p = 0.004), particularly in TNBC (p = 0.02).Conclusions These results position SLC38A2 as a selective target for inhibiting growth of Gln-dependent breast cancer cell lines.Subject terms: Breast cancer, Cancer metabolism  相似文献   
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The current study demonstrated that chronic peer victimization, as compared to time-limited victimization, is particularly associated with peer status and peer-reported adjustment at the adolescent transition. Using a cohort sequential design, a sample of 653 adolescents (48% female, 87% Caucasian) in Grades 6–8 were assessed at 3 annual time points; data captured indices of peer victimization, likeability, popularity, and several peer-reported indices of internalizing (e.g., sadness, worry) and externalizing (e.g., anger, fighting) symptoms across Grades 6–10. Four trajectories of victimization experiences were identified—chronic, high decreasing, low increasing, and low stable—suggesting instability in victimization experiences over time. Adolescents who experienced chronic victimization, as compared to those with low-stable, decreasing, or increasing levels of victimization, were rated by peers more often on indices of maladjustment and less often on measures of popularity and likeability. Findings highlight negative associations with chronic victimization and underscore the need for targeted interventions to prevent chronic victimization. Overall, findings further emphasize the role of chronicity in victimization and highlight the importance of identifying chronic victims for intervention and prevention efforts.  相似文献   
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Tissue temperature distribution plays a crucial role in the outcome of laser-induced thermotherapy (LITT), a technique employed for neoplasias removal. Since recent studies proposed LITT for pancreatic tumors treatment, assessment of temperature and of its effects around the laser applicator could be useful to define optimal laser settings. The aims of this work are temperature monitoring and measurement of ablated tissue volume in an ex vivo porcine pancreas undergoing double-applicator LITT. A three-dimensional numerical model is implemented to predict temperature rise and volumes of ablated tissue in treated pancreas. Experiments are performed to validate the model, with two modalities: (1) 12-fiber Bragg grating sensors are adopted to monitor the heating and cooling during LITT at several distances from the applicators tip, and (2) 1.5-T MR imaging is used to estimate the ablated volume. Experimental data agree with theoretical ones: at 2 mm from both applicators tips, the maximum temperature increase is approximately 60 °C downward from the tips, while it increases of about 40 °C and 30 °C, respectively, at the level and upward from the tips. This behavior occurs also at other distances, proving that the tissue downward from the tip is mostly heated. Furthermore, the estimated volume with MRI agrees with theoretical one (i.d., 0.91?±?0.09 vs. 0.95 cm3). The encouraging results indicate that the model could be a suitable tool to choose the optimal laser settings, in order to control the volume of ablated tissue.  相似文献   
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