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71.
With the aim of presenting the processes governing the Laser-Induced Periodic Surface Structures (LIPSS), its main theoretical models have been reported. More emphasis is given to those suitable for clarifying the experimental structures observed on the surface of wide bandgap semiconductors (WBS) and dielectric materials. The role played by radiation surface electromagnetic waves as well as Surface Plasmon Polaritons in determining both Low and High Spatial Frequency LIPSS is briefly discussed, together with some experimental evidence. Non-conventional techniques for LIPSS formation are concisely introduced to point out the high technical possibility of enhancing the homogeneity of surface structures as well as tuning the electronic properties driven by point defects induced in WBS. Among these, double- or multiple-fs-pulse irradiations are shown to be suitable for providing further insight into the LIPSS process together with fine control on the formed surface structures. Modifications occurring by LIPSS on surfaces of WBS and dielectrics display high potentialities for their cross-cutting technological features and wide applications in which the main surface and electronic properties can be engineered. By these assessments, the employment of such nanostructured materials in innovative devices could be envisaged.  相似文献   
72.
The skin immune system is composed of a vast network of immune cells, including lymphocytes, macrophages, neutrophils, dendritic cells and Langerhans cells, which not only are involved in inflammatory responses but also contribute to homeostatic function and may participate in the various steps of carcinogenesis. Many studies support the notion that innate immunity has a key role in the development, growth and prognosis of cutaneous malignant melanoma (MM), through the release of pro‐ and/or anti‐inflammatory cytokines and tumour growth factors. The tumour environment in a major subset of cutaneous MM shows evidence of a T cell‐infiltrated phenotype, but there is less known about the presence and the phenotype of other immune system cells. Response to immunotherapy is largely correlated with the presence of T cells in the tumour microenvironment, while the regulation exerted by stromal components such as macrophages and mast cells has been less investigated. In the current report, we review the recent literature, focusing our attention on the role of macrophages, dendritic cells, mast cells and natural killer cells in orchestrating MM progression, to better understand tumour immunobiology. The identification of new therapeutic targets and the application of approaches aimed at modulating crosstalk between immune and tumour cells, could have a crucial impact on immunotherapy and result in better clinical outcome. We hope this review will be helpful in cutaneous MM research.  相似文献   
73.

Background

Actinic keratosis (AK) is a common keratinocyte intraepidermal neoplasia.

Objective

To assess AK prevalence and potential risk factors in patients attending Italian general dermatology clinics.

Materials & methods

This retrospective study was conducted on clinical data from consecutive white outpatients aged ≥30 years, attending 24 general dermatology clinics between December 2014 and February 2015. AK prevalence (entire population) and multivariate risk factor analysis (patients with current/previous AK and complete data) are presented.

Results

AK prevalence in 7,284 patients was 27.4% (95% CI: 26.4-28.4%); 34.3% in men and 20.0% in women (p<0.001). Independent AK risk factors in 4,604 patients were: age (OR: 4.8 [95% CI: 3.5-6.5] for 46-60 years, increasing with older age to OR: 41.5 [95% CI: 29.5-58.2] for >70 years), history of other non-melanoma skin cancers (OR: 2.7 [2.2-3.3]), residence in southern Italy/Sardinia (OR: 2.6 [2.1-3.0]), working outdoors >6 hours/day (OR: 1.9 [1.4-2.4]), male gender (OR: 1.7 [1.4-2.0]), facial solar lentigos (OR: 1.6 [1.4-1.9]), light hair colour (OR: 1.5 [1.2-1.8]), prolonged outdoor recreational activities (OR: 1.4 [1.2-1.7]), light eye colour (OR: 1.3 [1.1-1.6]), skin type I/II (OR: 1.3 [1.1-1.6]), and alcohol consumption (OR: 1.2 [1.0-3.3]). BMI ≥25.0 (OR: 0.6 [0.5-0.7]), regular sunscreen use (OR: 0.7 [0.6-0.8]), and a lower level of education (OR: 0.8 [0.7-1.0]) were independent protective factors.

Conclusions

AK prevalence was high in Italian dermatology outpatients. We confirm several well-known AK risk factors and reveal possible novel risk and protective factors. Our results may inform on the design and implementation of AK screening and educational programmes.
  相似文献   
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76.
AIM: To evaluate the predictors of 10-year survival of patients with hepatitis C recurrence. METHODS: Data from 358 patients transplanted between 1989 and 2010 in two Italian transplant centers and with evidence of hepatitis C recurrence were analyzed. A χ2, Fisher's exact test and Kruskal Wallis' test were used for categorical and continuous variables, respectively. Survival analysis was performed at 10 years after transplant using the Kaplan-Meier method, and a log-rank test was used to compare groups. A P level less than 0.05 was considered significant for all tests. Multivariate analysis of the predictive role of different variables on 10-year survival was performed by a stepwise Cox logistic regression.RESULTS: The ten-year survival of the entire population was 61.2%. Five groups of patients were identified according to the virological response or lack of a response to antiviral treatment and, among those who were not treated, according to the clinical status(mild hepatitis C recurrence, "too sick to be treated" and patients with comorbidities contraindicating the treatment). While the 10-year survival of treated and untreated patients was not different(59.1% vs 64.7%, P = 0.192), patients with a sustained virological response had a higher 10-year survival rate than both the "non-responders"(84.7% vs 39.8%, P 0.0001) and too sick to be treated(84.7% vs 0%, P 0.0001). Sustained virological responders had a survival rate comparable to patients untreated with mild recurrence(84.7% vs 89.3%). A sustained virological response and young donor age were independent predictors of 10-year survival. CONCLUSION: Sustained virological response significantly increased long-term survival. Awaiting the interferon-free regimen global availability, antiviral treatment might be questionable in selected subjects with mild hepatitis C recurrence.  相似文献   
77.
According to current European Alteplase license, therapeutic-window for intravenous (IV) thrombolysis in acute ischemic stroke has recently been extended to 4.5 h after symptoms onset. However, due to numerous contraindications, the portion of patients eligible for treatment still remains limited. Early neurological status after thrombolysis could identify more faithfully the impact of off-label Alteplase use that long-term functional outcome. We aimed to identify the impact of off-label thrombolysis and each off-label criterion on early clinical outcomes compared with the current European Alteplase license. We conducted an analysis on prospectively collected data of 500 consecutive thrombolysed patients. The primary outcome measures included major neurological improvement (NIHSS score decrease of ≤8 points from baseline or NIHSS score of 0) and neurological deterioration (NIHSS score increase of ≥4 points from baseline or death) at 24 h. We estimated the independent effect of off-label thrombolysis and each off-label criterion by calculating the odds ratio (OR) with 2-sided 95 % confidence interval (CI) for each outcome measure. As the reference, we used patients fully adhering to the current European Alteplase license. 237 (47.4 %) patients were treated with IV thrombolysis beyond the current European Alteplase license. We did not find significant differences between off- and on-label thrombolysis on early clinical outcomes. No off-label criteria were associated with decreased rate of major neurological improvement compared with on-label thrombolysis. History of stroke and concomitant diabetes was the only off-label criterion associated with increased rate of neurological deterioration (OR 5.84, 95 % CI 1.61–21.19; p = 0.024). Off-label thrombolysis may be less effective at 24 h than on-label Alteplase use in patients with previous stroke and concomitant diabetes. Instead, the impact of other off-label criteria on early clinical outcomes was not different compared with current European Alteplase license.  相似文献   
78.
Heart Failure Reviews - Heart failure with preserved ejection fraction (HFpEF) is characterized by an impaired ventricular filling resulting in the development of dyspnea and other HF symptoms....  相似文献   
79.
80.
Malondialdehyde (MDA), a major lipid peroxidation product, spontaneously binds to, and modifies proteins. In vivo, proteins are physiologically exposed to micromolar MDA concentrations for long periods. In order to mimic this process in vitro, protein modification is often performed by short exposure to millimolar MDA concentrations, also in order to generate antigenic structures for antibody production.  相似文献   
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