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Abstract Background. The aim of this study is to critically evaluate the bond strength (BS) of Glass-Ionomer Cements (GIC) to dentine with microtensile (μTBS) and microshear (μSBS) BS tests by assessing their rankings and failure patterns. Methods. Samples were made on flat dentine surfaces and submitted to μTBS and μSBS. The materials used were: high viscosity GIC (Ketac(?) Molar Aplicap-KM), resin-modified GIC (Fuji II-FII), nano-filled resin-modified GIC (Ketac(?) N100-N100) and an etch-and-rinse adhesive system with a composite resin (Adper(?) Single Bond 2 and Z100(?)-Z100). All tests were performed with a Universal Testing Machine (24 h water storage, crosshead speed of 1 mm/min). Debonded surfaces were examined with a stereomicroscope (×40) to identify the failure mode. The data was analyzed with two-way ANOVA (p < 0.05) and LSD test. Results. Means were statistically different regarding the tests and materials, indicating that values for BS obtained for each material depend on the test performed. Failure analysis revealed that failures produced by μTBS were mainly cohesive for KM and FII. μSBS failures were mainly adhesive or mixed for all materials. For the μTBS, the rank was Z100 > FII > KM = N100, whereas for the μSBS it was Z100 = FII = KM > N100. Conclusion: It may be concluded that distinct micro-mechanical tests present different failure patterns and rankings depending on the material to be considered.  相似文献   
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Recently antibodies against neuronal receptors have been identified as cause of a new type of encephalitis. The anti-N-methyl-d-aspartate receptor (anti-NMDA-R) encephalitis is the prototype of these disorders. Patients have a high incidence of teratomata. Removal of teratoma is considered the essential treatment of anti-NMDA-R encephalitis. Here, we aimed to investigate whether neurologically asymptomatic individuals suffering from ovarian teratomata may have positive anti-NMDA-R antibodies to be detected by an established assay. Over a time period of 15 months, all patients suffering from ovarian teratomata without neurological symptoms were included in this prospective study. Twenty consecutive patients were pair matched to patients with other benign ovarian disease and healthy controls. Preoperatively, patients had a gynaecological examination, transvaginal ultrasound, neurological examination and determination of anti-NMDA-R antibodies. None of the patients or controls presented with neurological symptoms. All tumours could be removed completely by laparoscopy. Anti-NMDA-R antibodies were absent in the group of patients with teratomata as well as in patients with benign ovarian tumours and healthy controls. Testing for anti-NMDA-R antibodies revealed negative findings in well-characterised patients with ovarian teratomata lacking neurological symptoms. Our data support the current clinical practice that a systematic screening for anti-NMDA-R antibodies in teratoma patients is not indicated.  相似文献   
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Introduction: Nanomedicine has emerged as a major field of academic research with direct impact on human health. While a first generation of products has been successfully commercialized and has significantly contributed to enhance patient’s life, recent advances in material design and the emergence of new therapeutics are contributing to the development of more sophisticated systems. As the field matures, it is important to comprehend the challenges related to nanoparticle commercial development for a more efficient and predictable path to the clinic.

Areas covered: The review provides an overview of nanoparticle-based delivery systems currently on the market and in clinical trials, and discuss the principal challenges for their commercial development, both from a manufacturing and regulatory perspective, to help gain understanding of the translational path for these systems.

Expert opinion: Clinical translation of nanoparticle-based delivery systems remains challenging on account of their 3D nanostructure and requires robust nano-manufacturing process along with adequate analytical tools and methodologies. By identifying early enough in the development the product critical attributes and understanding their impact on the therapeutic performance, the developers of nanopharmaceuticals will be better equipped to develop efficient product pipelines. Second-generation products are expected to broaden nanopharmaceutical global market in the upcoming years.  相似文献   

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Fatigue is a frequent problem after surgical treatment of solid tumours. Aerobic exercise and psychosocial interventions have been shown to reduce the severity of this symptom in cancer patients. Therefore, we compared the effect of the two therapies on fatigue in a randomised controlled study. Seventy-two patients who underwent surgery for lung (n=27) or gastrointestinal tumours (n=42) were assigned to an aerobic exercise group (stationary biking 30 min five times weekly) or a progressive relaxation training group (45 min three times per week). Both interventions were carried out for 3 weeks. At the beginning and the end of the study, we evaluated physical, cognitive and emotional status and somatic complaints with the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core Module (EORTC-QLQ-30) questionnaire, and maximal physical performance with an ergometric stress test. Physical performance of the training group improved significantly during the programme (9.4±20 watts, p=0.01) but remained unchanged in the relaxation group (1.5±14.8 watts, p=0.37). Fatigue and global health scores improved in both groups during the intervention (fatigue: training group 21%, relaxation group 19%; global health of both groups 19%, p for all 0.01); however, there was no significant difference between changes in the scores of both groups (p=0.67). We conclude that a structured aerobic training programme improves the physical performance of patients recovering from surgery for solid tumours. However, exercise is not better than progressive relaxation training for the treatment of fatigue in this setting.  相似文献   
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