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31.
目的:评价INTRABEAM术中放射治疗系统临床应用的安全性和优势.方法:INTRABEAM对20例保乳手术患者实施术中瘤床放疗,均为单次照射每次20Gy,施用器规格为4.5cm(范围1.5-5.0cm),治疗持续时间35.5-51分钟.结果:术中照射治疗后有3例发生治疗区局部积液,经抽吸并加压包扎后愈合,乳房水肿1例.结论:INTRABEAM术中放射治疗系统近期无明显毒副作用,INTRABEAM术中放射治疗系统是一项安全良好耐受性技术,病人乐于接受.  相似文献   
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Cisplatin-related ototoxicity is a critical side effect of chemotherapy and can lead to irreversible hearing loss. This study aimed to assess the potential effect of the DNA methyltransferase (DNMT) inhibitor RG108 on cisplatin-induced ototoxicity. Immunohistochemistry, apoptosis assay, and auditory brainstem response (ABR) were employed to determine the impacts of RG108 on cisplatin-induced injury in murine hair cells (HCs) and spiral ganglion neurons (SGNs). Rhodamine 123 and TMRM were utilized for mitochondrial membrane potential (MMP) assessment. Reactive oxygen species (ROS) amounts were evaluated by Cellrox green and Mitosox-red probes. Mitochondrial respiratory function evaluation was performed by determining oxygen consumption rates (OCRs). The results showed that RG108 can markedly reduce cisplatin induced damage in HCs and SGNs, and alleviate apoptotic rate by protecting mitochondrial function through preventing ROS accumulation. Furthermore, RG108 upregulated BCL-2 and downregulated APAF1, BAX, and BAD in HEI-OC1 cells, and triggered the PI3K/AKT pathway. Decreased expression of low-density lipoprotein receptor-related protein 1 (LRP1) and high methylation of the LRP1 promoter were observed after cisplatin treatment. RG108 treatment can increase LRP1 expression and decrease LRP1 promoter methylation. In conclusion, RG108 might represent a new potential agent for preventing hearing loss induced by cisplatin via activating the LRP1-PI3K/AKT pathway.KEY WORDS: Cisplatin, DNMT, Apoptosis, Hair cell, Spiral ganglion neurons, RG108, Mitochondrial dysfunction, ROS  相似文献   
33.
网络课程作为终身教育学习资源的一种,越来越受到人们的重视.在网络课程中,是否具备良好的监控能力,是影响学习者学习效果的关键因素.而目前的网络监控普遍存在智能程度不高问题,无法满足网络监控的需要.该文将智能代理技术与电子学档结合起来对网络课程进行监控,以期对今后网络课程监控方面的研究提供一些帮助.  相似文献   
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本文对矿山粉尘和铸造粉尘的游离二氧化硅含量进行了红外分光光度法和焦磷酸重量法的对比测定。结果表明,红外法与重量法的结果之间有很好的相关性,其测定值在统计学上无显著性差异。两法测定值的相关回归方程:(?)=1.0001×-2.0610,r=0.947997。红外法的测定不受灰化的影响,对滤膜采集的粉尘中游离二氧化硅的含量测定是一简便、快速的方法,可较好地排除粉尘中难溶或不溶物质和无定形二氧化硅等因素的干扰,克服了重量法的不足。  相似文献   
36.
BackgroundThe effect of empagliflozin on the cardiovascular outcome is consistent in heart failure with reduced ejection fraction (HFrEF) patients regardless of the presence or absence of diabetes. More evidence is needed regarding the cost-effectiveness of empagliflozin in HFrEF patients. This study sought to evaluate the economic outcomes of adding empagliflozin to the standard treatment for HFrEF patients from the perspective of the Chinese healthcare system, and thus to provide information for decision makers.MethodsBased on the EMPEROR-Reduced clinical trial and other published literature data, the direct medical costs and quality-adjusted life years (QALYs) of patients with HFrEF over a 15-year study period were simulated by a Markov model, and the incremental cost-effectiveness ratio (ICER) was calculated. The price of empagliflozin referred to the data released by Menet, the hospitalization expenses and utility values were derived from published studies in China. A one-way sensitivity analysis and probabilistic sensitivity analysis were conducted to evaluate the robustness of the model.ResultsThe results of the cost-effectiveness analysis showed that the cost of the combination arm was $5,220.98, with a utility of 4.86 QALYs, and the cost of the standard arm was $4,873.96, with a utility of 4.68 QALYs, which equated to an ICER of $1,893.59 per QALY gained. The subgroup analysis showed that patients with HFrEF and diabetes in empagliflozin group had a higher QALY (4.62 vs. 4.35) and a lower cost ($5,213.28 vs. $5,958.60) than standard group. The corresponding ICER for non-diabetic patients was $2,568.15 per QALY. Deterministic sensitivity analysis showed robust results. At the willingness-to-pay threshold of 3 times gross domestic product (GDP) per capita ($31,510.57), almost all of the scattered points in three scenarios were below the threshold line.ConclusionsAt a willingness-to-pay threshold of $31,510.57, adding empagliflozin to standard treatment is a very cost-effective option for HFrEF patients with or without diabetes in China.  相似文献   
37.
More and more reports have pointed out that rotenone, as an insecticide, has high neurotoxicity and reproductive toxicity to livestock and mammals. As a highly physiological correlation system of internal organs, quasi-organs have great potential in the fields of drug toxicity and efficacy test, toxicology research, developmental biology and so on. In this study, brain organs (mBOs) derived from mouse neural stem cells were used to investigate the effects of rotenone on the physiological activity and epigenetic modification of mBOs. At the same time, Rotenone could significantly stimulate the increase of the concentration of LPO, lactic acid and hydroxyl radical in mBOs, and inhibit the expression of neuronal marker Tuj1, CHAT, PAX6 and so on. Further analysis showed that Rotenonem could induce mitochondrial damage in mBOs. The results of qPCR and Western blot showed that Rotenone could up-regulate the expressions of ferroptosis promoting protein p53, Cox2 and so on, while inhibit the expressions of negative regulatory protein of ferroptosis GPX4, FTH1, SLC7A11. In addition, the results of RRBS-Seq sequencing showed that the methylation modification at DMR level in Rotenone-treated mBOs group was significantly higher than that in Ctrl group. The results of KEGG analysis showed that compared with Ctrl, the genes with hypermethylation of promoter and Genebody in Rotenone-treated mBOs were mainly located in the Neuro active ligand-receptor interaction signal transduction pathway. In summary, rotenone can significantly lead to abnormal methylation of mouse brain organs, and lead to the loss of normal physiological function of neurons by inducing ferroptosis.  相似文献   
38.
Little is known about esophageal high-grade intraepithelial neoplasia dominated by cytological atypia (HGINc). We aimed to elucidate the endoscopic features of HGINc compared with esophageal high-grade intraepithelial neoplasia dominated by architectural atypia (HGINa). All patients pathologically diagnosed as esophageal high-grade intraepithelial neoplasia after endoscopic submucosal dissection at our center between January 2018 and December 2019 were included in this study. According to the pathological diagnosis, the patients were divided into two groups: HGINa group and HGINc group. Basic characteristics and endoscopic information were collected in detail. Data were analyzed statistically. Binary logistic regression was performed and a predictive model for HGINc was established. Then we evaluated its predictive value and built a nomogram for clinical application. A total of 175 patients were included in this study (126 with HGINa and 49 with HGINc). Among 228 lesions found in all patients, there were 148 HGINa and 80 HGINc. The independent relevant factors for HGINc were tobacco and alcohol usage, color, and gross type. To predict risk of HGINc, a three-factor model (TFM) was established with a highest area under curve (AUC) as 0.869 (95% CI, 0.852, 0.939). When the cut-off value was set as 0.3569184, the diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for HGINc was 81.14%, 88.75%, 77.03%, 67.62%, and 92.68%, respectively. HGINc differs greatly in endoscopic features from HGINa in our study. It’s important to reduce misdiagnosis that our model was established with good predictive value for clinical application.  相似文献   
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DBC1的研究进展   总被引:1,自引:0,他引:1  
DBC1是近年来新发现的一种蛋白,属于小GTP酶类Rho家族的非典型成员。最初因为在乳腺癌组织中杂合性缺失被鉴定出来的。目前关于DBC1在乳腺癌上的研究报道尚少。本文对国内外关于该基因的有关研究进行综述,了解其分子机制,基因表达情况。  相似文献   
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