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141.
The electrochemical behavior of some polybenzofulvene derivatives bearing bithiophene (BT) or terthiophene (TT) side chains was investigated by cyclic voltammetry. Very interestingly, the presence of unsubstituted terminal thiophene moieties allowed poly-6-BT-BF3k and poly-6-TT-BF3k to be cross-linked by electrochemical procedures. Conductive films were obtained by electrodeposition from solutions of these polymers onto electrode surfaces through the formation of covalent cross-linking due to dimerization (i.e. electrochemical oxidation) of the BT or TT side chains. The films showed electrochromic features and switched from yellow-orange (neutral) to green (positively charged) by switching the potential, and were stable to tenths of cycles, without degradation in the wet state in the electrolyte solution. Finally, the thin film obtained by electrodeposition of poly-6-TT-BF3k on a indium tin oxide (ITO) glass substrate showed in the neutral state a significantly red-shifted photoluminescence (PL) emission (∼40 nm red-shifted with respect to that of the corresponding film obtained by casting procedures), which was consistent with the presence of more conjugated moieties produced by the oxidative dimerization of the TT side chains. The innovative architecture and the easy preparation could lead to a broad range of applications in optoelectronics and bioelectronics for these cross-linked hybrid materials based on π-stacked polybenzofulvene backbones bearing oligothiophene side chains.

The electrochemical behavior of some polybenzofulvene derivatives bearing bithiophene (BT) or terthiophene (TT) side chains was investigated by cyclic voltammetry and cross-linked materials were obtained by dimerization of the BT or TT side chains.  相似文献   
142.

Purpose:

To report our clinical experience and 4-year follow-up results of Descemet stripping automated endothelial keratoplasty (DSAEK) with the suture pull-through insertion technique.

Methods:

This is a retrospective study of 195 eyes in which a posterior lamellar keratoplasty was performed between 2007 and 2011. The insertion of a folded donor lenticule was performed with a double-armed 10-0 suture using a straight transchamber needle and half-circle needle. Endothelial cell density was measured annually up to 4 years after the surgery, and cell loss was calculated based on the median preoperative donor endothelial cell density. Postoperative complications, primary graft failure, pupillary block, and dislocation of the donor tissue were assessed.

Results:

All patients underwent uncomplicated DSAEK. Data were available for 195 eyes (100%) at 1 year, 186 eyes (95.3%) at 2 years, 176 eyes (90.2%) at 3 years, and 160 eyes (82%) at 4 years. Median preop-erative donor endothelial cell density was 2688 cells/mm2 [interquartile range (IQR) 207.5 cells/mm2], which decreased by 27% at 1 year (1956 cells/mm2, IQR 264.8 cells/mm2), 31% at 2 years (1855 cells/mm2, IQR 320.5 cells/mm2), 35% at 3 years (1756.5 cells/mm2, IQR 306.5 cells/mm2), and 36% at 4 years (1709.5 cells/mm2, IQR 288,0 cells/mm2). Nine patients (4.6%) had a dislocation of donor tissue; all were successfully reattached with a second air injection. Only three eyes (1.5%) developed graft failure. Pupillary block was present in 15 eyes (7.7%).

Conclusion:

DSAEK with suture pull-through insertion of donor graft represents a simplified and safe technique that has endothelial cell loss comparable with other techniques and low rates of intraoperative and postoperative complications.  相似文献   
143.
144.
Journal of Thrombosis and Thrombolysis - To compare age at 1st ischaemic stroke (IS) in a cohort of juvenile (<?46 years of age) IS patients evaluated for the rs1801133...  相似文献   
145.
Cardiovascular Drugs and Therapy - The purpose of the present study was to compare the long-term effectiveness and safety of newly initiated anticoagulation with edoxaban (EDO) versus uninterrupted...  相似文献   
146.
Journal of Thrombosis and Thrombolysis - The actual Coronavirus Disease (COVID 19) pandemic is due to Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a member of the coronavirus...  相似文献   
147.
The long-term changes of liver stiffness (LS) in patients who achieve viral clearance after direct-acting anti-HCV therapy remain undefined. We conducted a multicentre prospective study to investigate this aspect. Patients with HCV infection treated with DAAs were enrolled from six Italian centres; they underwent clinical, biochemical, ultrasound and transient elastography evaluations before treatment (T0), 12 weeks (SVR12) and 24 months (T24) after the end of therapy. Among the 516 consecutive patients enrolled, 301 had cirrhosis. LS significantly decreased from T0 to SVR (14.3 vs 11.1 kPa, p = .002), with a progressive reduction until T24 (8.7 kPa, p < .001). However, only patients with steatosis and those who developed HCC did not experience a late improvement in LS. Multivariate analysis of baseline and follow-up variables identified steatosis as the only independent predictor of failure of LS improvement (OR 1.802, p = .013). ROC curve analysis of the association of LS with the risk of developing HCC showed that SVR12 ≥14.0 kPa had the highest accuracy (sensitivity 82%, specificity 99%; AUC: 0.774). Multivariate analysis revealed that LS was the only variable independently associated with an increased risk of developing HCC (OR 6.470, p = .035). Achieving an SVR was associated with a progressive, long-term decline of LS, suggesting a late improvement in liver fibrosis, besides the resolution of inflammation. Fatty liver and the development of HCC interfered with late reduction of LS. Patients with an LS ≥14 kPa at 12 weeks after the end of treatment were at higher risk for developing HCC.  相似文献   
148.
149.
Purpose

To compare the accuracy of Contrast-Enhanced Spectral Mammography (CESM), MG, US, and breast MRI in estimating the size of breast lesions requiring surgery. The postoperative histology size of the lesion was used as the gold standard.

Material and methods

Two hundred thirty-three non-benign lesions in 189 patients were included in the analyses. All the selected patients underwent CESM and at least one other conventional diagnostic exam (US, MG, or MRI). Subsequently, all the patients underwent surgery preceded by cytological/histological examination. The largest diameter of the lesion at imaging was measured by a radiologist with more than 10 years’ experience and then compared with the size of the lesion in the histological sample at the surgery (gold standard).

Results

Among the 233 breast lesions, 196 were evaluated with US, 206 with MG and 160 with MRI. We found no statistically significant differences between size measurements using CESM and MRI compared with the measurements at the surgery (p value 0.63 and 0.51), whereas a significant difference was found for MG and US (p?<?0.001).

Conclusion

CESM is a reliable method for estimating the size of breast lesions: its performance seems superior to US and MG and comparable to MRI.

  相似文献   
150.
BACKGROUND: The aim of the study is to analyze pancreatic metastases and their clinical, radiological, therapeutic and prognostic features. METHODS: Three cases of pancreatic metastases observed and a world literature review of 333 cases were recorded. RESULTS: Pancreatic metastases are due more frequently to renal cell carcinoma; they are usually metachronous and characterized by a long period of time between the resection of the primary tumor and their detection. The differential diagnosis with other pancreatic masses is difficult, but an accurate anamnesis, some peculiar findings of imaging techniques and percutaneous fine needle aspiration could allow preoperative diagnosis. Pancreatic resections are the treatment of choice allowing the better palliation and improving survival. 150/234 pancreatic metastases underwent pancreatic resections (resectability index = 64.1%); 88/132 patients are alive with a mean follow-up of 27.1 months; of the 44 dead patients the mean survival time was 21.3 months. Among pancreatic metastases the primary tumor with better prognosis is renal cell carcinoma. CONCLUSION: Pancreatic metastases are rare; their preoperative diagnosis is difficult but useful and possible. Surgical resection is suggested because the patient still may have a prolonged survival.  相似文献   
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