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超微超顺磁性氧化铁(USPIO)作为磁共振对比剂,可用来评价恶性肿瘤的淋巴结转移。与常规MRI对比,USPIO增强MRI能提高转移淋巴结检测的敏感性、特异性及准确性,并且能更好地鉴别转移及非转移淋巴结。本文就近年来USPIO增强MRI在头颈鳞癌(HNSCC)淋巴结转移中的相关研究及文献进行综述,评估USPIO增强MRI对检测HNSCC转移淋巴结的临床应用潜力及发展前景。  相似文献   
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Beta-thalassaemia causes defective haemoglobin synthesis leading to ineffective erythropoiesis, chronic haemolytic anaemia, and subsequent clinical complications. Blood transfusion and iron chelation allow long-term disease control, and haematopoietic stem cell transplantation offers a potential cure for some patients. Nonetheless, there are still many challenges in the management of beta-thalassaemia. The main treatment option for most patients is supportive care; furthermore, the long-term efficacy and safety of current therapeutic strategies are limited and adherence is suboptimal. An increasing understanding of the underlying molecular and cellular disease mechanisms plus an awareness of limitations of current management strategies are driving research into novel therapeutic options. Here we provide an overview of the current pathophysiology, clinical manifestations, and global burden of beta-thalassaemia. We reflect on what has been achieved to date, describe the challenges associated with currently available therapy, and discuss how these issues might be addressed by novel therapeutic approaches in development.  相似文献   
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The purpose of this study was to use agar as a multifunctional encapsulating material to allow drug and ferromagnetism to be jointly delivered in one nanoparticle. We successfully encapsulated both Fe3O4 and doxorubicin (DOX) with agar as the drug carrier to obtain DOX-Fe3O4@agar. The iron oxide nanoparticles encapsulated in the carrier maintained good saturation of magnetization (41.9 emu/g) and had superparamagnetism. The heating capacity test showed that the specific absorption rate (SAR) value was 18.9 ± 0.5 W/g, indicating that the ferromagnetic nanoparticles encapsulated in the gel still maintained good heating capacity. Moreover, the magnetocaloric temperature could reach 43 °C in a short period of five minutes. In addition, DOX-Fe3O4@agar reached a maximum release rate of 85% ± 3% in 56 min under a neutral pH 7.0 to simulate the intestinal environment. We found using fluorescent microscopy that DOX entered HT-29 human colon cancer cells and reduced cell viability by 66%. When hyperthermia was induced with an auxiliary external magnetic field, cancer cells could be further killed, with a viability of only 15.4%. These results show that agar is an efficient multiple-drug carrier, and allows controlled drug release. Thus, this synergic treatment has potential application value for biopharmaceutical carrier materials.  相似文献   
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Rare earth atoms exhibit several interesting properties, for example, large magnetic moments and luminescence. Introducing these atoms into a different matrix can lead to a material that shows multiple interesting effects. Holmium atoms were incorporated into an iron oxide nanoparticle and the concentration of the dopant atom was changed in order to determine its influence on the host crystal. Its magnetic and magneto-optical properties were investigated by vibrating sample magnetometry and Faraday rotation measurements. The luminescent characteristics of the material, in solution and incorporated in a polymer thin film, were probed by fluorescence experiments.  相似文献   
149.
Iron overload (IO) is poorly investigated in the congenital haemolytic anaemias (CHAs), a heterogeneous group of rare inherited diseases encompassing abnormalities of the erythrocyte membrane and metabolism, and defects of the erythropoiesis. In this study we systematically evaluated routine iron parameters and cardiac and hepatic magnetic resonance imaging, together with erythropoietin, hepcidin, non-transferrin bound iron (NTBI), and cytokine serum levels in patients with different CHAs. We found that 40% of patients had a liver iron concentration (LIC) >4 mg Fe/g dry weight. Hepatic IO was associated with ferritin levels (P = 0·0025), transferrin saturation (TfSat, P = 0·002) and NTBI (P = 0·003). Moreover, ferritin >500 μg/l plus TfSat >60% was demonstrated as the best combination able to identify increased LIC, and TfSat alteration as more important in cases with discordant values. Possible confounding factors, such as transfusions, hepatic disease, metabolic syndrome and hereditary haemochromatosis-associated mutations, had negligible effects on IO. Erythropoietin and hepcidin levels were increased in CHAs compared with controls, correlating with LIC and ferritin, respectively. Regarding cytokines, γ-interferon (IFN-γ) was increased, and both interleukin 6 and IFN-γ levels positively correlated with ferritin and hepcidin levels. Overall, these findings suggest the existence of a vicious cycle between chronic haemolysis, inflammatory response and IO in CHAs.  相似文献   
150.
We retrospectively assessed the characteristics of 165 MDS patients from our institution having received at least 20 RBC units. In the vast majority of them various comorbidities (range: 1–6 per patient) were registered including mainly cardiovascular disorders. Serum ferritin was over 1000 μg/L in about half of tested individuals. A chelator agent was initiated in 43.6% of patients (mainly low-risk MDS). Transformation in AML occurred in 46 cases (27.8%). Overall, 112 patients died during follow up. The cause of death was documented in 65 cases and included mainly MDS or AML resistance to therapy. There was a context of bacterial or fungal-related sepsis in 35.3% of cases. We noticed a correlation between survival and number of RBC transfusions. Median OS from the 20th RBC unit was significantly prolonged among the chelated subgroup. Consequences of transfusional iron overload and chelation need to be clarified in MDS patients.  相似文献   
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