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101.
102.
Magnetite nanoparticles were prepared by a non‐hydrolytic sol–gel (NHSG) process in the presence of benzyl alcohol. The obtained magnetite suspensions were mixed with an aliphatic epoxy resin and the formulations were photo‐polymerized to achieve composite materials with magnetic properties. The prepared magnetite nanoparticles and epoxy composites were fully characterized in terms of their magnetic properties.  相似文献   
103.
Within this work, we demonstrate that an easy soldering process in combination with wet chemical coating is suitable to realize a strong and reliable solder interconnection of Al substrates, even at short soldering times <5 s in ambient air. The microstructure of solder joints on wet chemically treated aluminum foils is investigated. A single and double zincate pre-treatment are compared to activate the Al surface, followed by electroless Ni plating. The quality of the solderable Ni surface is characterized by contact angle measurements, yielding good wettability (<60°), which is also achieved after isothermally heating (250 °C) the Ni-coated Al foils for 100 min. The microstructure of the Sn62Pb36Ag2 solder joints is investigated by SEM and EDX of cross sections, directly after soldering as well as after isothermal aging at 85 °C. Under the used soldering conditions, with a soldering temperature at about 280 °C, diffusion zones <500 nm were identified. Nonetheless, high peel forces after soldering >5 N mm−1 show stable values under aging conditions of 85 °C for 1000 hours. This could be correlated to a mixed fracture pattern, promoting the high adhesion due to the absence of a dominant failure mechanism.

High mechanical reliability of tin-based solder joints processed by joining copper and nickel-coated aluminium with short soldering times in ambient air.  相似文献   
104.
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106.
Basaloid squamous cell carcinoma is a biologically aggressive neoplasm mainly found in the head and neck region. Recently, four cases of basaloid squamous cell carcinoma of the bladder have been reported, and three of them occurred in patients with neurogenic bladder, repeated catheterizations and human papillomavirus infection of the urinary tract. To the best of our knowledge, none of the patients affected by basaloid squamous cell carcinoma of the bladder described in the literature had documented genital involvement by human papillomavirus. Herein, we describe the case of a woman with neurogenic bladder affected by basaloid squamous cell carcinoma of the bladder and by a concomitant genital tract human papillomavirus infection.  相似文献   
107.
108.
<正>The efficacy of platelet-rich plasma(PRP)to promote tissue regeneration has been largely confirmed in several clinical settings,such as in human maxillo-facial(Froum et al.,2002),heart(Vu et al.,2015)and orthopaedic surgery(Zhang and Wang,2010).Up to date,few studies are available regarding the topical use of platelet-rich plasma in models of  相似文献   
109.

Background

Pancreatic ductal adenocarcinoma (PDAC) is associated with poor prognosis. Gemcitabine is the standard chemotherapy for patients with metastatic pancreatic adenocarcinoma (MPA). Randomized clinical trials evaluating intensified chemotherapies including FOLFIRINOX and nab-paclitaxel plus gemcitabine (NAB+GEM) have shown improvement in survival. Here, we have evaluated the efficacy of intensified chemotherapy versus gemcitabine monotherapy in real-life settings across Europe.

Methods

A retrospective multi-center study including 1056 MPA patients, between 2012 and 2015, from nine centers in UK, Germany, Italy, Hungary and the Swedish registry was performed. Follow-up was at least 12 months. Cox proportional Harzards regression was used for uni- and multivariable evaluation of prognostic factors.

Results

Of 1056 MPA patients, 1030 (98.7%) were assessable for survival analysis. Gemcitabine monotherapy was the most commonly used regimen (41.3%), compared to FOLFIRINOX (n = 204, 19.3%), NAB+GEM (n = 81, 7.7%) and other gemcitabine- or 5-FU-based regimens (n = 335, 31.7%). The median overall survival (OS) was: FOLFIRINOX 9.9 months (95%CI 8.4–12.6), NAB+GEM 7.9 months (95%CI 6.2–10.0), other combinations 8.5 months (95%CI 7.7–9.3) and gemcitabine monotherapy 4.9 months (95%CI 4.4–5.6). Compared to gemcitabine monotherapy, any combination of chemotherapeutics improved the survival with no significant difference between the intensified regimens. Multivariable analysis showed an association between treatment center, male gender, inoperability at diagnosis and performance status (ECOG 1–3) with poor prognosis.

Conclusion

Gemcitabine monotherapy was predominantly used in 2012–2015. Intensified chemotherapy improved OS in comparison to gemcitabine monotherapy. In real-life settings, the OS rates of different treatment approaches are lower than shown in randomized phase III trials.  相似文献   
110.

Background

Immunoglobulin light chains are classified as middle molecule uremic toxins able to interact with B lymphocyte membranes leading to the activation of transmembrane signaling. The ensuing impairment of neutrophil function can contribute to the chronic inflammation state of uremic patients, and the increased risk of bacterial infections or vascular calcifications. The aim of this crossover observational study was to assess the difference in free light chain removal by three different hemodialysis filters in patients not affected by multiple myeloma.

Methods

Free light chain removal was compared in the polymethylmethacrylate (PMMA) membrane Filtryzer BK-F, the polyphenylene HFR17 filter and the conventional polysulfone filter F7HPS. Twenty chronic hemodialysis patients were enrolled: mean age was 67.7?±?17.0 years, M/F?=?14/6, dialysis vintage (months) 25.5?±?32.0. The patients were randomized into two groups of treatment lasting 6 weeks each. The dialysis sessions checked were the midweek sessions and the blood was drawn at times 0, 120’ and 240’. Kappa (k) and lambda (λ) light chain levels, β2microglobulin (β2M), C reactive protein (CRP) and albumin were checked.

Results

K light chain levels were 345.0?±?100.0 mg/L, λ light chains were 121.4?±?27.0 mg/L. The values of k light chains at times 120’ and 240’ were significantly lower with PMMA and HFR17 than those obtained with F7. The reduction ratio per session (RRs) for k light chains was 44.1?±?4.3% with HFR17, 55.3?±?3.4% with PMMA, 25.7?±?8.3% with F7 (p?=?0.018). The RRs for λ light chains was 30.3?±?2.9% with HFR17, 37.8?±?17.3% with PMMA, 14.0?±?3.9% with F7 (p?=?0.032). As to β2M, RRs was 42.4?±?3.2% with HFR17 vs. 33.9?±?2.8% with PMMA vs. 6.3?±?1.9% with F7 (p?=?0.022). The three filters tested showed no differences in CRP or albumin levels.

Conclusion

In terms of light chain and β2M removal, the PMMA and on-line HFR filters are similar and both are significantly more effective than the F7 filter in chronic dialysis patients.

Trial registration

The present trial was registered retrospectively (NCT02950389, 31/10/2016).
  相似文献   
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