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Christopher S. Sheppard Matteo Giletta Mitchell J. Prinstein 《Journal of clinical child and adolescent psychology》2019,48(2):218-227
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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Paola Saccomandi Emiliano Schena Francesco Giurazza Riccardo Del Vescovo Michele A. Caponero Luca Mortato Francesco Panzera Roberto L. Cazzato Francesco R. Grasso Francesco M. Di Matteo Sergio Silvestri Bruno B. Zobel 《Lasers in medical science》2014,29(2):607-614
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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Donato Mele Vittorio Smarrazzo Gianni Pedrizzetti Matteo Bertini Roberto Ferrari 《Echocardiography (Mount Kisco, N.Y.)》2019,36(10):1919-1929
In the past years, assessment of cardiac function has become possible through the analysis of intracardiac flow dynamics, performed noninvasively using phase‐contrast cardiac magnetic resonance and contrast and noncontrast ultrasound techniques. From 2013 to 2019, 9 echocardiographic investigations have considered 215 patients with cardiac resynchronization therapy (CRT) as a model for assessing flow dynamics within the left ventricle. Preliminary results have been reported about the acute hemodynamic effects of CRT and programming of the CRT device, showing the potential of an approach based on analysis of intracardiac flows. At present, there are only scarce data on the capability of intracardiac flow dynamics to predict LV remodeling after CRT and no information on clinical outcome prediction. Future investigations should be aimed at clarifying the mechanisms and impact of maladaptive intracardiac vortex dynamics on progressive LV remodeling as well as the prognostic meaning of implanted CRT device based on cardiac flow analysis. 相似文献
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Stefano Calzetti Monica Angelini Anna Negrotti Elena Marchesi Matteo Goldoni 《Journal of neural transmission (Vienna, Austria : 1996)》2014,121(5):499-506
It is currently controversial if and in which terms Parkinson’s disease (PD) and restless legs syndrome (RLS) are linked in co-morbid association. In a cohort of 106 de novo PD patients (67 male and 39 female, aged 42–83 years), 15 of them developed RLS, which was prospectively assessed at 6-month intervals from the starting of dopamine(DA)ergic therapy. The incidence rate of total RLS was 47 per 1,000 case/person per year and 37 per 1,000 case/person per year after the exclusion of possible “secondary” forms of the disorder (n = 3). These figures are higher than those reported in an incidence study conducted in German general population (Study of Health in Pomerania), in which the method of ascertainment of RLS similar to ours has been used. An incidence rate of total RLS significantly higher than that reported in the above-mentioned study was found in the age ranges 55–64 years and in the age range 45–74 years standardized to European general population 2013 (70 and 53 per 1,000 case/person per year, respectively, p < 0.01). Ten out of 12 patients (83.3 %) developed RLS within 24 months from the starting of DAergic medication (median latency 7.5 months). These findings support the view that sustained DAergic therapy could represent the critical factor inducing an increased incidence of RLS in patients with PD and that the latter disease should be regarded as the condition predisposing to the occurrence of the former and not viceversa as previously hypothesized. The mechanism underlying the increased incidence of RLS remains unclear and deserves further investigation. 相似文献
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Mario Migliario Pamela Pittarella Matteo Fanuli Manuela Rizzi Filippo Renò 《Lasers in medical science》2014,29(4):1463-1467
Low-level laser therapy (LLLT) is widely used in regenerative medicine and in dental therapy by virtue of its beneficial effects in a plethora of pathological conditions. In this study, the effect of a 980 nm diode laser on pre-osteoblasts proliferation has been evaluated, along with reactive oxygen species (ROS) production. We hypothesized that ROS were a key factor in LLLT-induced pre-osteoblasts proliferation, as it is known that ROS can induce the activation of many biological pathways, leading to cell proliferation, differentiation or apoptosis. Murine pre-osteoblasts MC3T3 cells were irradiated with different energy outputs (1–50 J) in the absence or presence of the antioxidant N-Acetyl-L-cysteine (NAC). Laser treatment, in the absence of NAC, was able to induce a fluence-dependent statistically significant increase in ROS generation, while the presence of NAC strongly inhibited it. Cell proliferation, measured after laser stimulation, was significantly increased both at low and higher energy, with a peak at 10 J in the absence of the antioxidant. On the contrary, in the presence of NAC, laser irradiation was not able to induce any cell proliferation, suggesting a crucial role of ROS in this laser-induced cell effect. These results suggest that LLLT may be a useful tool for bone regeneration therapy and an effective range of fluences to be used is indicated. 相似文献
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