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Malignant glioma is the most common intracranial tumor with a dismal prognosis. The radiosensitizing effect of silver nanoparticles (AgNPs) on glioma both in vitro and in vivo had been demonstrated in the previous studies of our group. However, the underlying mechanism is still unclear. Consistent with previous studies, a size and dose dependent antitumor effect and significant radiosensitivity enhancing effect of AgNPs were observed in our experiment system. We also found that cell protective autophagy could be induced by AgNPs and/or radiation, which was verified by the use of 3-MA. The mechanism through which had autophagy and the enhancement of radiosensitivity taken place was further investigated with inhibitors of ERK and JNK pathways. We demonstrated that ERK and JNK played pivotal roles in the radiosensitivity enhancement. Inhibiting ERK and JNK with U0126 and SP600125 respectively, we found that the autophagy level of the cells treated with AgNPs and radiation were attenuated. Moreover, SP600125 down-regulated the apoptosis rate of the co-treated cells significantly. Taken together, the present study would have important impact on biomedical applications of AgNPs and clinical treatment for glioma.  相似文献   
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Calcium, cell signalling and cataract   总被引:5,自引:0,他引:5  
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OBJECTIVE: To conduct a systematic review to gather the available evidence on the optimum timing of the radiotherapy in relation to autologous breast reconstruction. MATERIAL AND METHODS: The data was extracted from scientific databases, and a manual follow-up of references. The studies were selected which included at least 20 patients with any method of autologous breast reconstruction who were treated with adjuvant radiotherapy either before or after their reconstruction, and had addressed the effects of radiotherapy on the cosmetic outcome in their results. The principal outcome was cosmetic appearance. Secondary outcomes were immediate and delayed complications. RESULTS: We could not find any randomised controlled trial on this topic. Ten studies were included, most were retrospective, heterogeneous in terms of control groups, radiation doses, follow-up duration, and outcome measurements. Two studies included no control groups, and four studies compared the outcomes of patients with radiotherapy either before (n=3) or after (n=1) autologous breast reconstruction. The overall incidence of complications was increased in patients with radiotherapy in three out of these four studies. Only four studies directly compared the outcomes of patients who received radiotherapy before with patients who received radiotherapy after autologous breast reconstruction and two out of these reported worse outcomes associated with post-reconstruction radiotherapy. CONCLUSIONS: Despite the paucity of the published data, the current evidence suggests that the radiation has a deleterious effect on autologous flap reconstruction. Until better methods of radiation delivery can be devised to minimise the long term radiation sequelae in the irradiated tissue, delayed reconstruction seems to be a safe option in most of the cases. However, the findings from these studies should be interpreted with great caution before generalising from their results.  相似文献   
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Summary The whole cell lipid and sterol content of the drug resistant strains cyh1, cyh3 and cyh4 was compared with that of wild type by thin layer and gas liquid chromatography and by UV spectrophotometric analysis. The cyh3 and cyh4 strains had a decreased content of the unsaturated 18:1 fatty acid oleic acid, a decreased content of ergosterol and an increased content of 24,28 dehydroergosterol with respect to wild type. The cyh1 strain, however, only showed a decreased content of ergosterol and an increased content of 24,28 dehydro-ergosterol when compared to wild type.  相似文献   
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Twelve microsatellite markers were developed for the scallop Pecten maximus. The markers were tested in three geographically diverse populations and all markers were polymorphic in all three populations. The mean number of alleles per locus ranged from 2 to 10.67 and the observed and expected heterozygosity ranged from 0.05 to 0.67 and 0.05 to 0.81 respectively. Some loci showed evidence of null alleles and an excess of homozygotes in some populations but 9 loci conformed to Hardy–Weinberg expectations. These new loci can be combined with previously published microsatellites to create a powerful suite of markers for genetic analyses.  相似文献   
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Aimthe concept of ‘advanced midwifery practice’ is explored to a limited extent in the international literature. However, a clear conception of advanced midwifery practice is vital to advance the discipline and to achieve both internal and external legitimacy. This concept analysis aims to clarify advanced midwifery practice and identify its components.Methodsa review of the literature was executed using Rodgers’ evolutionary method of concept analysis to analyze the attributes, references, related terms, antecedents and consequences of advanced midwifery practice.Resultsan international consensus definition of advanced midwifery practice is currently lacking. Four major attributes of advanced midwife practitioners (AMPs) are identified: autonomy in practice, leadership, expertise, and research skills. A consensus was found on the need of preparation at master’s level for AMPs. Such midwives have a broad and internationally varied scope of practice, fulfilling different roles such as clinicians, clinical and professional leaders, educators, consultants, managers, change agents, researchers, and auditors. Evidence illustrating the important part AMPs play on a clinical and strategic level is mounting.Key conclusionsthe findings of this concept analysis support a wide variety in the emergence, titles, roles, and scope of practice of AMPs. Research on clinical and strategic outcomes of care provided by AMPs supports further implementation of these roles. As the indistinctness of AMPs’ titles and roles is one of the barriers for implementation, a clear conceptualization of advanced midwifery practice seems essential for successful implementation.Implications for practicean international debate and consensus on the defining elements of advanced midwifery practice could enhance the further development of midwifery as a profession and is a prerequisite for its successful implementation. Due to rising numbers of AMPs, extension of practice and elevated quality requirements in healthcare, more outcomes research exclusively evaluating the contribution of AMPs to healthcare becomes possible and desirable.  相似文献   
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Contributors     
《Cardiology Clinics》2020,38(1):iii-v
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