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991.
In this paper, the best laser powder bed fusion (L-PBF) printing conditions for FeSi steels with two different Si content (3.0% and 6.5%) are defined. Results show very strict processing window parameters, following a lack of fusion porosity at low specific energy values and keyhole porosity in correspondence with high specific energy values. The obtained microstructure consists of grains with epitaxial growth starting from the grains already solidified in the underling layer. This allows the continuous growth of the columnar grains, directed parallel to the built direction of the component. The magnetic behaviour of FeSi6.5 samples, although the performances found do not still fully reach those of the best commercial electrical steels (used to manufacture magnetic cores of electrical machines and other similar magnetic components), appears to be quite promising. An improvement of the printing process to obtain thin sheets with increased Si content, less than 0.5 mm thick, with accurate geometry and robust structures, can result to an interesting technology for specific application where complex geometries and sophisticated shapes are required, avoiding mechanical machining processes for electrical steel with high silicon content.  相似文献   
992.
993.
Background: Cryoablation of accessory pathways (APs) is effective and very safe in children, as previously reported by our group. The aim of this retrospective study was to evaluate the current efficacy of 3D non-fluoroscopic cryoablation of right sided APs in children, comparing results obtained with the Ensite VelocityTM and the more recent Ensite PrecisionTM 3D mapping systems. Methods and Results: From January 2016 to December 2019, 102 pediatric patients [mean age 12.5 ± 2.8, 62 males (61% of total cohort)] with right APs underwent 3D non-fluoroscopic transcatheter cryoablation at our Institution. Fifteen (14.7%) patients had previously undergone catheter ablation. Acute procedural success rate was 95.1% (n = 97). No significant differences were detected in acute success rates achieved with Ensite VelocityTM or Ensite PrecisionTM systems nor between manifest (94%) and concealed APs (100%). No permanent complications occurred. During follow-up (428 ± 286 days, median 396 days [interquartile range 179-713]), 19 patients (19.6%) had recurrences. Recurrences were more frequent for parahissian/anterior APs compared to midseptal/posterior and lateral APs (p = 0.043). Recurrences were not related to the Ensite system used. A redo ablation procedure was attempted in 13 cases, 11 cryoablation and 2 radiofrequency ablations: the former was successful in 10 cases out of 11 (90.9%). Conclusion: 3D cryoablation of right-sided APs is associated with a very high acute success rate with limited use of fluoroscopy, resulting in great benefit to the children. Recurrence rates are not high and patients can be retreated with cryo-energy with higher success rates.  相似文献   
994.
995.
In phase III ImPassion130 trial, the addition of immunotherapy to chemotherapy improved overall survival in metastatic triple-negative breast cancer patients. This benefit was significant only in patients harboring PD-L1-positive tumors, suggesting that stratification according to response biomarkers is needed to achieve consistent responses. Besides PD-L1 expression, a variety of potential biomarkers are under investigation for predicting immunotherapy efficacy in breast cancer, such as tumor-infiltrating lymphocytes, gene signatures, tumor mutational burden, microsatellite instability, and gut microbiome. Enriching future trials through these biomarkers could help identifying the population of responders, realizing what has been called precision immunotherapy.  相似文献   
996.
Prandoni P 《Blood》2005,106(13):4027-4033
Venous thromboembolism (VTE) is a frequent complication in cancer patients and represents an important cause of morbidity and mortality. Especially in patients who have a poor life expectancy, preventing death from pulmonary embolism is the mainstay of treatment. Critically ill patients should promptly be administered thrombolytic drugs. Except for selected patients requiring aggressive therapy, the initial VTE treatment should be conducted with either adjusted-dose unfractionated heparin or fixed-dose low-molecular-weight heparin (LMWH). LMWHs have the potential to greatly simplify the initial treatment of VTE, making the treatment of suitable patients feasible in an outpatient setting. During anticoagulant therapy, cancer patients have a 2- to 4-fold higher risk of recurrent VTE and major bleeding complications when compared with noncancer patients. The long-term administration of LMWH should be considered as an alternative to anti-vitamin K drugs in patients with advanced disease and in those with conditions limiting the use of oral anticoagulants. Prolongation of anticoagulation should be considered for as long as the malignant disorder is active. The evidence of lowered cancer mortality in patients on LMWH has stimulated renewed interest in these agents as antineoplastic drugs and raises the distinct possibility that cancer and thrombosis share common mechanisms.  相似文献   
997.
998.
Thrombotic thrombocytopenic purpura (TTP) is a rare disorder of small vessels that is associated with deficiency of the von Willebrand factor-cleaving protease, ADAMTS13. The presence of anti-ADAMTS13 autoantibodies is considered a factor predisposing to relapses. Despite close monitoring and intensive plasma treatment, in these patients acute episodes are still associated with substantial morbidity and mortality rates, and the optimal therapeutic option should be prevention of relapses. This study was conducted in a patient with recurrent TTP due to high titers of ADAMTS13 inhibitors, who used to have 2 relapses of TTP a year. The study compared the standard treatment plasma exchange with rituximab. Results documented that plasma exchange had only a small transient effect on ADAMTS13 activity and inhibitors; on the contrary, prophylaxis with rituximab was associated with disappearance of anti-ADAMTS13 antibodies, a progressive recovery of protease activity, and it allowed the patient to maintain a disease-free state during a more than 2-year follow-up.  相似文献   
999.
Previous studies have shown that the allergic late airway response (LR) is dependent on the leukotriene (LT) pathway in Brown Norway (BN) rats. In this same model, interleukin-2 (IL-2) has been shown to increase allergic airway responses without increasing LT production. This study examined the relationship between the upregulation of cellular immunity with IL-2 and the LT pathway in ovalbumin-sensitized BN rats. Airway responsiveness to LTD(4) was significantly increased in BN rats pretreated with IL-2 (20,000 U twice a day for 4.5 days). Treatment with montelukast, a cysteinyl LT(1) receptor antagonist, blocked IL-2's induced increase of the LR to ovalbumin challenge. When cytokine expression was assessed either by semiquantitative polymerase chain reaction or in situ hybridization, we found that montelukast decreased the amount of IL-4 mRNA expression in the lungs while increasing the amount of interferon-gamma mRNA expression 8 hours after challenge. These results indicate that upregulation of cellular immunity with IL-2 can increase the sensitivity of the airways to LTD(4) and that inhibition of the LT pathway will block the LR and modulate cytokine expression after antigen challenge.  相似文献   
1000.
Quality of life in dependent older adults living at home   总被引:10,自引:0,他引:10  
The purpose of medical interventions today is to favor the duration of life and to assure its quality. For a proper evaluation of the quality of life (QoL) of the elderly, it is important to assess not only the health status, but also psychological, functional and existential domains. Up to now, QoL of the dependent older living at home does not seem to have received sufficient attention. This study is a population based, cross-sectional health survey, and tries to give a picture of the QoL conditions of a group of dependent elderly living at home, using a specifically designed structured interview. In addition to this interview the Activities of Daily Living (ADL) Index and the Zung rating scale for Anxiety and Depression (AD) were administered to a total of 167 elderly (60 males and 107 females). The most interesting results of the study are the following: (1) the definition of dependence is often worsen by cultural prejudices; (2) psychopathological factors show a deep negative effect on 'attitudes towards life' of the dependent elderly; (3) QoL of the dependent elderly people in this sample is mainly negatively influenced by the degree of depression. We believe that the 'QoL-oriented' therapeutic strategy should consider more articulated and multidisciplinary geriatric and psychosocial interventions in this population.  相似文献   
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