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1.
Xiumei Jiang Xiaowei Zhang Patrick Gray Jiwen Zheng Timothy R. Croley Peter P. Fu 《journal of environmental science and health part c-environmental carcinogenesis & ecotoxicology reviews》2019,37(2):116-131
Gold nanoparticles (Au NPs) hold great promise in food, industrial and biomedical applications due to their unique physicochemical properties. However, influences of the gastrointestinal tract (GIT), a likely route for Au NPs administration, on the physicochemical properties of Au NPs has been rarely evaluated. Here, we investigated the influence of GIT fluids on the physicochemical properties of Au NPs (5, 50, and 100?nm) and their implications on intestinal epithelial permeability in vitro. Au NPs aggregated in fasted gastric fluids and generated hydroxyl radicals in the presence of H2O2. Cell studies showed that GIT fluids incubation of Au NPs affected the cellular uptake of Au NPs but did not induce cytotoxicity or disturb the intestinal epithelial permeability. 相似文献
2.
Wang-Shu Zhu Si-Ya Shi Ze-Hong Yang Chao Song Jun Shen 《World journal of gastroenterology : WJG》2020,26(11):1208-1220
BACKGROUND Postoperative liver failure is the most severe complication in cirrhotic patients with hepatocellular carcinoma(HCC) after major hepatectomy. Current available clinical indexes predicting postoperative residual liver function are not sufficiently accurate.AIM To determine a radiomics model based on preoperative gadoxetic acid-enhanced magnetic resonance imaging for predicting liver failure in cirrhotic patients with HCC after major hepatectomy.METHODS For this retrospective study, a radiomics-based model was developed based on preoperative hepatobiliary phase gadoxetic acid-enhanced magnetic resonance images in 101 patients with HCC between June 2012 and June 2018. Sixty-one radiomic features were extracted from hepatobiliary phase images and selected by the least absolute shrinkage and selection operator method to construct a radiomics signature. A clinical prediction model, and radiomics-based model incorporating significant clinical indexes and radiomics signature were built using multivariable logistic regression analysis. The integrated radiomics-based model was presented as a radiomics nomogram. The performances of clinical prediction model, radiomics signature, and radiomics-based model for predicting post-operative liver failure were determined using receiver operating characteristics curve, calibration curve, and decision curve analyses.RESULTS Five radiomics features from hepatobiliary phase images were selected to construct the radiomics signature. The clinical prediction model, radiomics signature, and radiomics-based model incorporating indocyanine green clearance rate at 15 min and radiomics signature showed favorable performance for predicting postoperative liver failure(area under the curve: 0.809-0.894). The radiomics-based model achieved the highest performance for predicting liver failure(area under the curve: 0.894; 95%CI: 0.823-0.964). The integrated discrimination improvement analysis showed a significant improvement in the accuracy of liver failure prediction when radiomics signature was added to the clinical prediction model(integrated discrimination improvement = 0.117, P =0.002). The calibration curve and an insignificant Hosmer-Lemeshow test statistic(P = 0.841) demonstrated good calibration of the radiomics-based model. The decision curve analysis showed that patients would benefit more from a radiomics-based prediction model than from a clinical prediction model and radiomics signature alone.CONCLUSION A radiomics-based model of preoperative gadoxetic acid–enhanced MRI can be used to predict liver failure in cirrhotic patients with HCC after major hepatectomy. 相似文献
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目的:探讨电视胸腔镜(VATS)解剖性肺段切除术与肺叶切除术治疗Ia 期非小细胞肺癌(NSCLC)患者的手术情况及对患者肺功能的影响。方法:选取我院手术治疗的Ⅰa期NSCLC患者,收集时间2014年1月至2016年12月,根据术式不同分为两组,均采用VATS手术治疗,A组(54例)患者采用解剖性肺段切除术、B组(60例)采用肺叶切除术治疗,对比两组患者的手术效果及术后肺功能变化。结果:A组患者的手术时间、清扫淋巴结数目与B组比较差异无统计学意义(P>0.05);A组患者的手术出血量、术后胸腔引流量、术后拔管时间、术后住院时间均显著的低于B组患者(P<0.05);术前,A组和B组患者的FEV1%、FVC%、MVV%测定值差异无统计学意义(P>0.05),术后3个月复查,A组患者的FEV1%、FVC%、MVV%测定值均显著高于B组患者(P<0.05);手术后,A组患者的并发症发生率(7.41%)低于B组患者(13.33%),但是差异无统计学意义(P>0.05)。结论:VATS解剖性肺段切除术治疗Ⅰa期NSCLC患者具有手术创伤小、术后恢复快、对患者肺功能影响更小的优势。 相似文献
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目的探讨舒芬太尼在肾母细胞瘤患儿术后镇痛中的应用效果及对患儿免疫功能的影响。方法采用随机数字表法将42例肾母细胞瘤患儿分为低剂量、中剂量和高剂量组,每组14例,低剂量组、中剂量组、高剂量组患儿术后舒芬太尼镇痛剂量分别为1.0、2.5、4.0μg/kg。术后6、24、48 h,采用中文版儿童疼痛行为量表(FLACC)评估三组患儿的镇痛效果,以及不良反应发生情况;麻醉前和术后1、24、72 h,检测三组患儿免疫功能指标,包括免疫球蛋白(Ig)G、IgA、IgM。结果术后6、24、48 h,中剂量组、高剂量组患儿FLACC评分均低于低剂量组患儿,差异均有统计学意义(P﹤0.05)。术后1、24、72 h,低剂量组患儿IgG、IgA、IgM水平均低于本组麻醉前,差异均有统计学意义(P﹤0.05);术后1、24 h,中剂量组和高剂量组患儿IgG、IgA、IgM水平均低于本组麻醉前,差异均有统计学意义(P﹤0.05),但术后72 h,中剂量组和高剂量组患儿IgG、IgA、IgM水平与麻醉前比较,差异均无统计学意义(P﹥0.05)。低剂量组患儿未发生不良反应,中剂量组患儿发生恶心1例,高剂量组患儿发生恶心5例、呕吐3例。结论2.5μg/kg的舒芬太尼在肾母细胞瘤患儿术后镇痛中效果明显,且对患儿的免疫系统发挥一定的保护作用,可以减轻患儿术后免疫功能抑制。 相似文献
7.
Zheng Xingming Ding Yanling Zhao Xiaowei Bai Yu Li Xiaofeng Zhao Kai 《Remote sensing letters.》2019,10(6):563-572
Vegetation water content (VWC) is the key input parameter for a soil moisture retrieval algorithm based on microwave remote sensing, and VWC uncertainty can limit the estimated accuracy of soil moisture. There has been little research on VWC algorithm development and validation in China, and the uncertainty of the VWC estimation method has not been well evaluated. Therefore, the aim of this study is to evaluate the uncertainty of the VWC estimation method used in the SMAP (Soil Moisture Active Passive) algorithm on three spatial scales (the point-scale, 30 m scale, and 1 km scale) for maize in northeast China. Results from three ground experimental datasets showed that the SMAP VWC estimation method was strongly biased with an average overestimation of 1.16 kg m?2,1.04 kg m?2, and 1.13 kg m?2 for the point-scale, 30 m scale, and 1 km scale respectively, and maximum bias occurred in the mid-stage of maize. Also, a new power relationship between NDVI (Normalized Difference Vegetation Index) and VWC was proposed for the 30 m scale based on Sentinel 2 NDVI and field VWC values from 2017 experiment, with respective R2 (coefficient of determination) and Root Mean Squared Error (RMSE) values of 0.80 and 0.67 kg m?2. The results confirmed that this power relationship was still suitable for VWC estimation at the 1 km scale, and it has smaller bias than the original SMAP VWC method. Future work will be carried out to evaluate the applicability of this VWC estimation method over a lager region. It is expected that it can improve the accuracy of soil moisture by providing high precision VWC input parameters. 相似文献
8.
Xin Yi Wong Andrew Qi Jun Lim Qianyu Shen John Whay Kuang Chia Min Hoe Chew Wah Siew Tan 《Current medical research and opinion》2020,36(10):1677-1686
Abstract
Objective
Ras wild-type metastatic colorectal cancers (mCRC) may be treated with anti-vascular endothelial growth factor (VEGF) or anti-epidermal growth factor receptor (EGFR) agents. We aim to estimate patients’ preferences for mCRC treatment and relative importance of cost, efficacy improvement, avoidance of side effects and therapy convenience, and relative uptake between profiles that resemble Bevacizumab (anti-VEGF) and Cetuximab (anti-EGFR), two commonly prescribed mCRC targeted therapies. 相似文献9.
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目的 检测分析被诊断为X连锁视网膜色素变性(XLRP)的三个中国家系内的基因突变。设计 基因研究。研究对象 三个中国XLRP家系共27位受试者(其中18人为男性)。方法 由同一医生收集家系成员的详细临床资料并进行眼部检查,采集三个家系的先证者及有条件采血者的外周静脉血,提取基因组DNA。应用PCR技术扩增RPGR和RP2基因的全部外显子和内含子交界区序列,包括RPGR基因15号外显子开放阅读框,产物直接测序进行突变分析。主要指标 临床特征及基因测序结果。结果 基因筛查证实了两个RPGR基因的新型无义突变(c.1541C>G;p.S514X 和 c.2833G>T;p.E945X) 及一个错义突变(c.607G>C;p.A203P)。基因型-表型的相关性分析表明家系3患者在接近ORF15下游位置存在突变,这种突变导致视锥细胞功能的早期丧失。ORF15无义突变的女性携带者临床表型重,呈现出部分显性遗传的特点。结论 本研究证实了三种RPGR基因的新型突变,这一结果扩展了RPGR的突变谱及表型谱。 相似文献