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61.
Journal of Neuro-Oncology - Practice patterns vary for adjuvant treatment of 1p/19q-codeleted oligodendroglioma patients. This study evaluates the outcomes of adjuvant (aRT) versus salvage...  相似文献   
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Heterotopic ossification (HO) is the formation of pathological bone in ectopic sites and it can have serious consequences for functional outcomes. For many years, its main clinical relevance was as a rare complication of elective joint arthroplasty or CNS injury and a number of prophylaxes were developed to mitigate against it in these settings. As a consequence of changes in patterns of wounding and survival in conflicts since the turn of the century, post‐traumatic HO has become much more common and case severity has increased. It represents one of the main barriers to rehabilitation in a large cohort of combat‐injured patients. However, extant prophylaxes have not been shown to be effective or appropriate in this patient cohort. In addition, the lack of reliable early detection or means of predicting which patients will develop HO is another barrier to effective prevention. This review examines the current state of understanding of post‐traumatic HO including the historical context, epidemiology, pathophysiology, clinical issues, currently prophylaxis and detection, management, and potential future approaches. Our aims are to highlight the current lack of effective means of early detection and prevention of HO after major trauma and to stimulate research into novel solutions to this challenging problem. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1061–1068, 2018.  相似文献   
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Swelling, erosion, deformation, and consolidation properties can affect the performance of cellulose ethers, the most commonly used matrix former in hydrophilic sustained tablet formulations. The present study was designed to comparatively evaluate the swelling, erosion, compression, compaction, and relaxation properties of the cellulose ethers in a comprehensive study using standardised conditions. The interrelationship between various compressional models and the inherent deformation and consolidation properties of the polymers on the derived swelling and erosion parameters are consolidated. The impact of swelling (Kw) on erosion rates (KE) and the inter-relationship between Heckel and Kawakita plasticity constants was also investigated. It is evident from the findings that the increases in both substitution and polymer chain length led to higher Kw, but a lower KE; this was also true for all particle size fractions regardless of polymer grade. Smaller particle size and high substitution levels tend to increase the relative density of the matrix but reduce porosity, yield pressure (Py), Kawakita plasticity parameter (b?1) and elastic relaxation. Both KW versus KE (R2?=?0.949–0.980) and Py versus. b?1 correlations (R2?=?0.820–0.934) were reasonably linear with regards to increasing hydroxypropyl substitution and molecular size. Hence, it can be concluded that the combined knowledge of swelling and erosion kinetics in tandem with the in- and out-of-die compression findings can be used to select a specific polymer grade and further to develop and optimize formulations for oral controlled drug delivery applications.  相似文献   
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AIM: To examine an increased risk of esophageal adenocarcinoma is restricted to patients who develop Barrett's esophagus or whether esophagitis per is a risk factor for adenocarcinoma. METHODS: A population-based cohort of patients with histological evidence of esophagitis without Barrett's esophagus was constructed using electronic pathology reports relating to all esophageal biopsies in Northern Ireland between 1993 and 1996. Person-years of follow-up and incident cases of esophageal cancer were calculated by linking the cohort to death files and the Northern Ireland Cancer Registry records. Standardized incidence ratios (SIR) were calculated for esophageal cancers (adenocarcinoma, squamous cell carcinoma (SCC), and historically unspecified cancers). RESULTS: A total of 2 013 patients in the cohort provided 13 559 patient-years of follow-up (mean follow-up 6.7 years). None of the patients developed adenocarcinoma. Three patients developed SCC, and six developed histologically unspecified cancers. The SIR for all esophageal cancers and for SCC were 2.73 (95%CI 1.25-5.19) and 2.93 (95%CI 0.61-8.59), respectively. In a sensitivity analysis in which all unspecified esophageal cancers were treated as adenocarcinomas, the SIR for adenocarcinoma was 2.64 (0.97-5.75). CONCLUSION: The risk of adenocarcinoma is not elevated in patients with histological evidence of esophagitis without Barrett's esophagus; however, these patients may have a moderately increased risk of SCC. Further studies are required to confirm these findings, which suggest that Barrett's esophagus, not esophagitis, is the key precursor lesion in the development of adenocarcinoma.  相似文献   
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Alginate hydrogels have been used widely in tissue engineering for cell encapsulation for several reasons: low toxicity, the ability to gel under gentle condition and compatibility with cells. In this study, we determined the effect of different concentrations of alginate on encapsulation of 3T3 fibroblast cells at two different cell seeding densities. Live/dead staining and MTT assay were performed at regular intervals up to 4 weeks. A Hoechst 33258 assay was done to validate the MTT results. There were more dead cells on day 1 for the higher concentrations of alginate while at, the lower concentration of alginate, cell proliferation and spheroid formation occurred more quickly. Furthermore, at low cell seeding density, cell proliferation was prolonged compared to the intermediate seeding density. In conclusion, by altering both alginate concentration and cell seeding density, proliferation and spheroid formation can be controlled.  相似文献   
68.
Atopic dermatitis imposes a significant burden on patients, families and healthcare systems. Management is difficult, due to disease heterogeneity, co-morbidities, complexity in care pathways and differences between national or regional healthcare systems. Better understanding of the mechanisms has enabled a stratified approach to the management of atopic dermatitis, supporting the use of targeted treatments with biologicals. However, there are still many issues that require further clarification. These include the definition of response, strategies to enhance the responder rate, the duration of treatment and its regimen (in the clinic or home-based), its cost-effectiveness and long-term safety. The EAACI Guidelines on the use of dupilumab in atopic dermatitis follow the GRADE approach in formulating recommendations for each outcome and age group. In addition, future approaches and research priorities are discussed.  相似文献   
69.
For the diagnosis of ocular myasthenia gravis (ocular MG), testing of the muscles close to the affected ones may be important. The relative importance of several methods: stimulated single fiber EMG (stimulated SFEMG), repetitive nerve stimulation test (RNS) of orbicularis oculi muscle, and infrared reflection oculography (IROG) was investigated. Thirty-two patients in whom a diagnosis of ocular MG was considered on clinical grounds were admitted to the study. Based on the results of the three neurophysiological tests, the patients could be divided in three groups: a first group with an abnormal stimulated SFEMG, and an abnormal RNS and/or abnormal IROG; a second group with only a slightly abnormal stimulated SFEMG; and a third group with normal tests in all three tests. The clinical diagnosis of ocular MG was made in all 11 patients of the first group; in 86% (6 of 7) of the patients of the second group; and in 7% (1 of 14) of the patients of the third groups. This study demonstrates that the orbicularis oculi muscle is a suitable muscle for stimulated SFEMG in patients with ocular MG, and that the results obtained with this technique showed a better relation with the clinical diagnosis than those of the two other techniques. We also demonstrate that there is no additional value in studying the jitter with different stimulation rates in patients with suspected ocular MG. © 1993 John Wiley & Sons, Inc.  相似文献   
70.
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