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Predicting Hepatocellular Carcinoma Using Brightness Change Curves Derived From Contrast-enhanced Ultrasound Images
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作者 CHEN Ying-Ying JIANG Shang-Lin +3 位作者 HUANG Liang-Hui ZENG Ya-Guang WANG Xue-Hua ZHENG Wei 《生物化学与生物物理进展》 北大核心 2025年第8期2163-2172,共10页
Objective Primary liver cancer,predominantly hepatocellular carcinoma(HCC),is a significant global health issue,ranking as the sixth most diagnosed cancer and the third leading cause of cancer-related mortality.Accura... Objective Primary liver cancer,predominantly hepatocellular carcinoma(HCC),is a significant global health issue,ranking as the sixth most diagnosed cancer and the third leading cause of cancer-related mortality.Accurate and early diagnosis of HCC is crucial for effective treatment,as HCC and non-HCC malignancies like intrahepatic cholangiocarcinoma(ICC)exhibit different prognoses and treatment responses.Traditional diagnostic methods,including liver biopsy and contrast-enhanced ultrasound(CEUS),face limitations in applicability and objectivity.The primary objective of this study was to develop an advanced,lightweighted classification network capable of distinguishing HCC from other non-HCC malignancies by leveraging the automatic analysis of brightness changes in CEUS images.The ultimate goal was to create a user-friendly and cost-efficient computer-aided diagnostic tool that could assist radiologists in making more accurate and efficient clinical decisions.Methods This retrospective study encompassed a total of 161 patients,comprising 131 diagnosed with HCC and 30 with non-HCC malignancies.To achieve accurate tumor detection,the YOLOX network was employed to identify the region of interest(ROI)on both B-mode ultrasound and CEUS images.A custom-developed algorithm was then utilized to extract brightness change curves from the tumor and adjacent liver parenchyma regions within the CEUS images.These curves provided critical data for the subsequent analysis and classification process.To analyze the extracted brightness change curves and classify the malignancies,we developed and compared several models.These included one-dimensional convolutional neural networks(1D-ResNet,1D-ConvNeXt,and 1D-CNN),as well as traditional machine-learning methods such as support vector machine(SVM),ensemble learning(EL),k-nearest neighbor(KNN),and decision tree(DT).The diagnostic performance of each method in distinguishing HCC from non-HCC malignancies was rigorously evaluated using four key metrics:area under the receiver operating characteristic(AUC),accuracy(ACC),sensitivity(SE),and specificity(SP).Results The evaluation of the machine-learning methods revealed AUC values of 0.70 for SVM,0.56 for ensemble learning,0.63 for KNN,and 0.72 for the decision tree.These results indicated moderate to fair performance in classifying the malignancies based on the brightness change curves.In contrast,the deep learning models demonstrated significantly higher AUCs,with 1D-ResNet achieving an AUC of 0.72,1D-ConvNeXt reaching 0.82,and 1D-CNN obtaining the highest AUC of 0.84.Moreover,under the five-fold cross-validation scheme,the 1D-CNN model outperformed other models in both accuracy and specificity.Specifically,it achieved accuracy improvements of 3.8%to 10.0%and specificity enhancements of 6.6%to 43.3%over competing approaches.The superior performance of the 1D-CNN model highlighted its potential as a powerful tool for accurate classification.Conclusion The 1D-CNN model proved to be the most effective in differentiating HCC from non-HCC malignancies,surpassing both traditional machine-learning methods and other deep learning models.This study successfully developed a user-friendly and cost-efficient computer-aided diagnostic solution that would significantly enhances radiologists’diagnostic capabilities.By improving the accuracy and efficiency of clinical decision-making,this tool has the potential to positively impact patient care and outcomes.Future work may focus on further refining the model and exploring its integration with multimodal ultrasound data to maximize its accuracy and applicability. 展开更多
关键词 computer-aided diagnostic deep learning hepatocellular carcinoma contrast-enhanced ultrasound brightness change curve
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Positive mindset,bright future
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作者 李玉莲 《疯狂英语(新读写)》 2025年第8期71-72,80,共3页
In life,we are bound to encounter various difficulties and setbacks.However,it is of great significance to maintain a positive attitude when were facing these challenges.For me,this lesson was deeply impressed upon me... In life,we are bound to encounter various difficulties and setbacks.However,it is of great significance to maintain a positive attitude when were facing these challenges.For me,this lesson was deeply impressed upon me during a particularly tough period. 展开更多
关键词 bright future maintaining positivity DIFFICULTIES challenging period setbacks positive mindset
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The strategy to improve the brightness of organic small-molecule fluorescent dyes for imaging
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作者 Junliang Zhou Tian-Bing Ren Lin Yuan 《Chinese Chemical Letters》 2025年第8期179-189,共11页
Organic small molecule fluorophores have been widely used in biology and biochemistry to study cellular structures and processes at high spatial and temporal resolution.Small-molecule dyes offer various benefits,such ... Organic small molecule fluorophores have been widely used in biology and biochemistry to study cellular structures and processes at high spatial and temporal resolution.Small-molecule dyes offer various benefits,such as high photostability,low molecular weight,and great biocompatibility.However,the poor brightness of most of conventional dyes in biological environments limits their use in high-quality superresolution fluorescence imaging.Chemists have conceived and developed many methods to enhance the brightness of fluorophores,including structural alterations that raise extinction coefficients and quantum yields.This review outlines current attempts and substantial advances achieved by chemists to improve the brightness of organic small-molecule fluorescent dyes,such as scaffold rigidification and twisted intramolecular charge transfer(TICT)inhibition.We think that this review will help researchers understand the chemical mechanisms involved in increasing the brightness of fluorophores for biological applications. 展开更多
关键词 Small-molecule fluorescent dyes brightNESS Fluorescence quantum yield TICT Structure modification
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Efficacy of bright light therapy for perinatal depression:A metaanalysis of a randomized controlled trial
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作者 Xue Yang Yuan-Yuan Gao +8 位作者 Shu-Qi Xu Jin-Cheng Wang Yu-Jie Ma Li-Huan Jiao Lan Wang Xue-Yi Wang Shahid Bashir Cui-Xia An Ran Wang 《World Journal of Meta-Analysis》 2025年第1期29-37,共9页
BACKGROUND Pharmacological treatments are commonly used in individuals experiencing perinatal depression(PPD);however,a debate regarding the reproductive safety of antidepressants is ongoing.Many pregnant women opt to... BACKGROUND Pharmacological treatments are commonly used in individuals experiencing perinatal depression(PPD);however,a debate regarding the reproductive safety of antidepressants is ongoing.Many pregnant women opt to discontinue antidepressant out of concern about potential negative effects on the developing fetus,while slow and ineffective antidepressant medications hinder improved outcomes in women with PPD.In recent years,bright light therapy(BLT)has gained traction as a treatment option for PPD;however,clinical trials findings examining the efficacy of BLT in this population have been inconclusive.AIM To validate the feasibility and safety of BLT for the treatment of PPD.METHODS We performed a meta-analysis of randomized controlled trials of patients with PPD treated with BLT vs placebo following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis.We searched PubMed,Embase,the Cochrane Library,and Web of Science for randomized controlled studies published up to December 2023.The results were evaluated using the standardized mean difference of improvement for depression scores and odds ratios(ORs)for remission rate,response rate,incidence of adverse events,and dropout rate.RESULTS The BLT group had higher PPD response rate[50.68%vs 33.08%;OR=2.05;95% confidence interval(CI):1.25-3.35;P=0.004;I^(2)=35%]and remission rate(54.10%vs 18.52%;OR=5.00;95%CI:2.09-11.99;P=0.0003;I^(2)=0%)than the placebo group.Improvements in depression scores were higher in the BLT group than the placebo group for the overall efficacy(standardized mean difference=-0.47;95%CI:-0.80 to-0.13;P=0.007).No significant differences between the two groups in drop-outs(21.84%vs 29.63%;OR=0.63;95%CI:0.31-1.29;P=0.21;I^(2)=0%)or adverse events(17.89%vs 9.68%;OR=2.01;95%CI:0.95-4.25;P=0.07;I^(2)=0%)were observed.CONCLUSION BLT can potentially treat PPD,showing better results than the control group in this study.BLT is effective and safe and could increase the available therapeutic options for PPD. 展开更多
关键词 bright light therapy Randomized controlled trial Perinatal depression PREGNANCY META-ANALYSIS
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Brightness temperature simulation of subarctic lake-ice evolution by HIGHTSI and SMRT model 被引量:1
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作者 ZHANG Yixiao QIU Yubao +3 位作者 PENG Chongtai Bin CHENG SHI Lijuan Matti LEPPARANTA 《Advances in Polar Science》 CSCD 2024年第3期303-323,共21页
Microwave brightness temperature(TB)can be used to retrieve lake ice thickness in the Arctic and subarctic regions.However,the accuracy of the retrieval is affected by the physical properties of lake ice.To improve th... Microwave brightness temperature(TB)can be used to retrieve lake ice thickness in the Arctic and subarctic regions.However,the accuracy of the retrieval is affected by the physical properties of lake ice.To improve the understanding of how lake ice affects TB,numerical modeling was applied.This study combined a physical thermodynamic ice model HIGHTSI with a microwave radiation transfer model SMRT to simulate the TB and lake ice evolution in 2002-2011 in Hulun Lake,China.The reanalyzed meteorological data were used as atmospheric forcing.The ice season was divided into the growth period,the slow growth period,and the ablation period.The simulations revealed that TB was highly sensitive to ice thickness during the ice season,especially vertical polarization measurement at 18.7 GHz.The quadratic polynomial fit for ice thickness to TB outperformed the linear fit,regardless of whether lake ice contained bubbles or not.A comparison of the simulated TB with space-borne TB showed that the simulated TB had the best accuracy during the slow growth period,with a minimum RMSE of 4.6 K.The results were influenced by the bubble radius and salinity.These findings enhance comprehension of the interaction between lake ice properties(including ice thickness,bubbles,and salinity)and TB during ice seasons,offering insights to sea ice in the Arctic and subarctic freshwater observations. 展开更多
关键词 lake ice evolution HIGHTSI SMRT ice thickness passive microwave brightness temperature
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Asymptotic analysis on bright solitons and breather solutions of a generalized higher-order nonlinear Schrödinger equation in an optical fiber or a planar waveguide
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作者 Xin Zhao Zhong Du +2 位作者 Li-Jian Zhou Rong-Xiang Liu Xu-Hu Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期154-160,共7页
We study a generalized higher-order nonlinear Schr¨odinger equation in an optical fiber or a planar waveguide.We obtain the Lax pair and N-fold Darboux transformation(DT)with N being a positive integer.Based on L... We study a generalized higher-order nonlinear Schr¨odinger equation in an optical fiber or a planar waveguide.We obtain the Lax pair and N-fold Darboux transformation(DT)with N being a positive integer.Based on Lax pair obtained by us,we derive the infinitely-many conservation laws.We give the bright one-,two-,and N-soliton solutions,and the first-,second-,and Nth-order breather solutions based on the N-fold DT.We conclude that the velocities of the bright solitons are influenced by the distributed gain function,g(z),and variable coefficients in equation,h_(1)(z),p_(1)(z),r_(1)(z),and s_(1)(z)via the asymptotic analysis,where z represents the propagation variable or spatial coordinate.We also graphically observe that:the velocities of the first-and second-order breathers will be affected by h_(1)(z),p_(1)(z),r_(1)(z),and s_(1)(z),and the background wave depends on g(z). 展开更多
关键词 optical fiber planar waveguide Darboux transformation bright soliton BREATHER
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Evaluating the Effects of Graviton Redshift upon Spiral Galaxy Rotation Curves, Surface Brightness Magnitudes and Gravitational Lensing
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作者 Firmin J. Oliveira 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期967-985,共19页
The effects of the gravitational redshift of gravitons upon spiral galaxy rotation energy are compared to the standard mass to light analyses in obtaining rotation curves. The derivation of the total baryonic matter c... The effects of the gravitational redshift of gravitons upon spiral galaxy rotation energy are compared to the standard mass to light analyses in obtaining rotation curves. The derivation of the total baryonic matter compares well with the standard theory and the rotation velocity is matched to a high precision. The stellar mass distributions obtained from the fit with graviton energy loss are used to derive the surface brightness magnitudes for the galaxies, which agree well with the observed measurements. In a new field of investigation, the graviton theory is applied to the observations of gravitational lenses. The results of these applications of the theory suggest that it can augment the standard methods and may eliminate the need for dark matter. 展开更多
关键词 GRAVITONS Gravitational Redshift Surface brightness Gravitational Lens Lens Mass
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Comprehensive Quality Control of Brightness Temperature Data Detected by a Microwave Radiometer
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作者 Qiang MA 《Meteorological and Environmental Research》 2024年第6期7-9,16,共4页
There are abnormal data of brightness temperature detected by a microwave radiometer in daily use.In this paper,based on the statistical analysis of the observation data of MP3000 microwave radiometer in the southern ... There are abnormal data of brightness temperature detected by a microwave radiometer in daily use.In this paper,based on the statistical analysis of the observation data of MP3000 microwave radiometer in the southern suburb of Beijing,check of extreme values,time consistency inspection,precipitation inspection,consistency discrimination,power spectrum estimation,and other quality control methods were used to evaluate the data of brightness temperature obtained by the microwave radiometer.It was compared with the observation data of a meteorological tower in Xianghe Station.It is found that the profiles of temperature detected by the microwave radiometer after quality control were very close to the observation results of the tower,indicating that the quality control scheme of the microwave radiometer is feasible and effective. 展开更多
关键词 Microwave radiometer Quality control Estimation of brightness temperature Temperature profile
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A rapid assessment of MWRI-RM/FY3G brightness temperature 被引量:1
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作者 Wenying He Xinran Xia +5 位作者 Shengli Wu Peng Zhang Hongbin Chen Xiang'ao Xia Yuquan Zhou Miao Cai 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第3期42-46,共5页
2023年4月发射的FY-3G上搭载17个频率的测雨微波成像仪(MWRI-RM),其业务定标的微波亮温(Tb)数据于2023年10月23日公开发布.本文比对了发布10天的MWRI-RM与全球降水测量(GPM)卫星上的微波成像仪(GMI)相匹配的Tb数据,并借助辐射传输模式... 2023年4月发射的FY-3G上搭载17个频率的测雨微波成像仪(MWRI-RM),其业务定标的微波亮温(Tb)数据于2023年10月23日公开发布.本文比对了发布10天的MWRI-RM与全球降水测量(GPM)卫星上的微波成像仪(GMI)相匹配的Tb数据,并借助辐射传输模式进行双差分(DD)交叉定标分析,旨在快速评估新一代MWRI-RM观测数据质量.观测比较表明,MWR1-RM与GMI测量的Tb一致性很好,大多通道的平均偏差(MBE)和均方根误差(RMSE)均小于1K.两种传感器由于观测角度略有不同在水面产生约0.5 K差异.DD分析也展示出MWRI-RM的大多数通道性能与GMI相当接近,尤其是首次启用的高频166 GHz和183 GHz. 展开更多
关键词 FY3G MWRI-RM GMI 亮度温度 双差分方法
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Electrodeposition behavior of bright nickel in air and water-stable betaine·HCl-ethylene glycol ionic liquid 被引量:5
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作者 龚凯 华一新 +4 位作者 徐存英 张启波 李艳 汝娟坚 介亚菲 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第7期2458-2465,共8页
The electrodeposition behaviors of nickel on glassy carbon(GC) and carbon steel(CS) electrodes were investigated in the14.3%-85.7%(mole fraction) betaine.HCl ethylene glycol(EG) ionic liquid using cyclic volta... The electrodeposition behaviors of nickel on glassy carbon(GC) and carbon steel(CS) electrodes were investigated in the14.3%-85.7%(mole fraction) betaine.HCl ethylene glycol(EG) ionic liquid using cyclic voltammetry and chronoamperometry.The results indicated that the reduction of Ni(Ⅱ) on CS electrode via a diffusion-controlled quasi-reversible process was much more facile and easier than that occurred on GC electrode,which followed a diffusion-controlled three-dimensional instantaneous nucleation and growth.Scanning electron microscopy was used to observe that the deposit was dense and contained fine crystallites with average size of(80±4) nm.Energy dispersive spectrometer analysis showed that the obtained deposit was metallic nickel.X-ray diffraction spectroscopy indicated that(111) plane was the most preferred crystal orientation.The nickel deposit was luminous and bright,and had good adhesion with the CS substrate. 展开更多
关键词 ELECTRODEPOSITION bright nickel nucleation mechanism betaine·HCl ethylene glycol
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Bright Yellow 2烤烟热激蛋白90生物信息学分析 被引量:17
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作者 陈二龙 苏家恩 +4 位作者 范志勇 朱凯 王德勋 孙军伟 宋朝鹏 《南方农业学报》 CAS CSCD 北大核心 2017年第10期1734-1740,共7页
【目的】分析Bright Yellow 2烤烟热激蛋白90(HSP90)的生物学信息,为揭示烘烤过程中烟叶的烘烤特性提供理论依据。【方法】从NCBI中获取Bright Yellow 2烤烟HSP90蛋白序列Nt HSP-1、Nt HSP-2和Nt HSP-3(Gen Bank登录号分别为BAL42333、B... 【目的】分析Bright Yellow 2烤烟热激蛋白90(HSP90)的生物学信息,为揭示烘烤过程中烟叶的烘烤特性提供理论依据。【方法】从NCBI中获取Bright Yellow 2烤烟HSP90蛋白序列Nt HSP-1、Nt HSP-2和Nt HSP-3(Gen Bank登录号分别为BAL42333、BAL42332和BAM24708),利用生物信息学软件对各序列进行理化特性、跨膜区、信号肽、亚细胞定位、二级结构和三级结构预测分析。【结果】Bright Yellow 2烤烟Nt HSP-1、Nt HSP-2和Nt HSP-3的氨基酸数量分别为812、811和699个,均以酸性氨基酸含量较多,其中谷氨酸(Glu)含量最高,理论等电点均小于5.00,二级结构均以α-螺旋(H)和无规则卷曲(C)为主。Nt HSP-1和Nt HSP-2的亲水性较高,具有较高的稳定性,属于分泌蛋白,具有锚定结构,定位于内质网,其三级结构呈现"r"形,N端内部具有Mg2+结合位点、HATPase_c(ATP酶)和top6b(DNA拓扑异构酶VI)功能域;Nt HSP-3为非分泌型蛋白,定位于叶绿体,三级结构呈现"i"形,N端含有Mg2+结合位点和HATPase_c功能域。【结论】Nt HSP-1和Nt HSP-2可能与烟叶耐烤性有关,而Nt HSP-3可能与烟叶易烤性有关。 展开更多
关键词 烤烟 brightYellow2 热激蛋白90(HSP90) 生物信息学 烘烤
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NK细胞亚群CD56^(bright)在帕金森患者外周血中的表达及临床意义 被引量:2
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作者 李湘青 殷欣 +1 位作者 赵雪莲 赵培庆 《山东大学学报(医学版)》 CAS 北大核心 2021年第2期34-40,共7页
目的探讨帕金森病(PD)患者外周血中NK细胞亚群CD56^(bright)的表达及其临床意义。方法选择2017年10月至2019年12月淄博市中心医院神经内科门诊就诊与住院治疗的PD患者56例(PD组),以及年龄、性别、生活环境相匹配的健康对照者50例(对照... 目的探讨帕金森病(PD)患者外周血中NK细胞亚群CD56^(bright)的表达及其临床意义。方法选择2017年10月至2019年12月淄博市中心医院神经内科门诊就诊与住院治疗的PD患者56例(PD组),以及年龄、性别、生活环境相匹配的健康对照者50例(对照组),均为同期健康查体的健康中老年人。采用ELISA法检测PD组患者外周血细胞因子水平;流式细胞术分析NK细胞及其亚群百分比;Hoehn-Yahr分期量值表和帕金森病评定量表评分(UPDRS)对PD组患者进行分层,分析CD56^(bright)NK细胞比值与PD患者疾病进程的相关性;最后,培养分选的CD56^(bright)NK细胞亚群,进一步明确其分泌的细胞因子在两组中的差别。结果PD组血清中细胞因子水平明显高于对照组[IL-1β(t=2.46,P=0.0154)、IL-6(t=3.19,P=0.0019)、TNF-α(t=3.37,P=0.0011)、IFN-γ(t=6.36,P<0.001)];更重要的是,PD组NK细胞(t=3.13,P=0.0078)及CD56^(bright)细胞亚群(t=4.23,P<0.001)比值增高,且CD56^(bright)细胞亚群比值与PD疾病进程呈正相关[Hoehn-Yahr分期(t=3.79,P=0.0052)、UPDRS评分(t=3.08,P=0.041)];分选CD56^(bright)细胞亚群进行培养,利用LPS刺激后发现PD组可分泌更多的细胞因子[IL-1β(t=2.89,P=0.0446)、IL-6(t=3.15,P=0.0347)、TNF-α(t=4.59,P=0.0101)、IFN-γ(t=4.79,P=0.0087)]。结论NK细胞及其CD56^(bright)亚群在PD患者中高表达,CD56^(bright)通过分泌细胞因子促进PD的疾病进程,可成为该类疾病新型诊断生物标记物与预后预测新靶点。 展开更多
关键词 帕金森病 NK细胞 CD56^(bright)亚群 疾病预后 细胞因子
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脐血中CD56^(bright)CD16^(dim)/^-NK细胞亚群的检测 被引量:3
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作者 孙健 陈军浩 张葵 《中国实验诊断学》 2012年第11期2060-2062,共3页
目的了解新生儿脐血NK细胞和CD56bright CD16dim/-NK细胞亚群的比率,探讨CD56bright CD16dim/-NK细胞在脐血低免疫应答中的作用。方法使用血细胞分析仪计数淋巴细胞;采用流式细胞术检测脐血、母亲及对照组中NK细胞和CD56bright CD16dim/... 目的了解新生儿脐血NK细胞和CD56bright CD16dim/-NK细胞亚群的比率,探讨CD56bright CD16dim/-NK细胞在脐血低免疫应答中的作用。方法使用血细胞分析仪计数淋巴细胞;采用流式细胞术检测脐血、母亲及对照组中NK细胞和CD56bright CD16dim/-NK细胞亚群的比率。结果脐血中淋巴细胞计数显著高于母亲及对照组;NK细胞比率无显著性差异;CD56bright CD16dim/-NK细胞高于母亲及对照组;母亲组CD56bright CD16dim/-NK细胞高于对照组。结论脐血中丰富的CD56bright CD16dim/-NK细胞是脐血低免疫应答的原因之一。 展开更多
关键词 脐血 NK细胞 CD56bright CD16dim -NK细胞
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High Brightness,High Power Density Fiber Coupling of High Power Laser Diode
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作者 王晓薇 肖建伟 +5 位作者 王仲明 马骁宇 刘宗顺 方高瞻 张敬明 冯小明 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第9期1112-1115,共4页
The output radiation from the 100μm×1μm aperture of a high power Laser Diode (LD) is efficiently coupled into a 50μm multimode optical fiber.The fiber output of the high power LD with high brightness and high ... The output radiation from the 100μm×1μm aperture of a high power Laser Diode (LD) is efficiently coupled into a 50μm multimode optical fiber.The fiber output of the high power LD with high brightness and high power density is achieved.The power density is up to 3 6×104W/cm2 and the coupling efficiency is 70%.The extreme divergence and the astigmatism of high power LDs require the optics with complex lens structures and high performance.A double-curved lens with two crossed cylindrical lenses structured on both sides of the glass substrate is used in the coupling system. 展开更多
关键词 high power LD double-curved lens fiber coupling high brightness high power density
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Synthesis of a Fluorophore with Improved Optical Brightness
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作者 Macduff Okuom Mark Wilson +9 位作者 Jordan Groathouse Junsik Lee Dave Symonsbergen Casey Gustafson Mitch Trauernicht Homar Barcena Cassie Reicks Sharmin Sikich Raychelle Burks Andrea Holmes 《International Journal of Organic Chemistry》 2013年第4期256-261,共6页
The synthesis and characterization of a novel fluorophore(1), with potential application as an optical brightener are reported. This compound was prepared by reacting 4,4-diaminostilbene-2,2-disulfonic acid with cyanu... The synthesis and characterization of a novel fluorophore(1), with potential application as an optical brightener are reported. This compound was prepared by reacting 4,4-diaminostilbene-2,2-disulfonic acid with cyanuric chloride in the presence of Na2CO3 followed by the addition of trityl aniline. Solution and solid state fluorescence demonstrated a strong blue/purple emission centered at 450 nm. 1H-NMR spectroscopy, mass spectrometry analysis, elemental analysis, and DOSY-NMR were used for the characterization of the fluorophore. 展开更多
关键词 OPTICAL brightENER FLUOROPHORE Diaminostilbene Cyanuric CHLORIDE OPTICAL brightNESS
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RS-based Analysis of the Correlation between Brightness Temperature and Vegetation Cover—A Case Study of Neijiang City,Sichuan Province of China
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作者 薛万蓉 许辉熙 +2 位作者 但尚铭 何政伟 仇文侠 《Journal of Landscape Research》 2012年第2期35-37,共3页
Landsat TM data(June 23,1988,May 6,2007) and Landsat ETM+data(May 10,2000) of Neijiang City,Sichuan Province was taken as the data source,brightness temperature of the study area was obtained by using TM/ETM+thermal i... Landsat TM data(June 23,1988,May 6,2007) and Landsat ETM+data(May 10,2000) of Neijiang City,Sichuan Province was taken as the data source,brightness temperature of the study area was obtained by using TM/ETM+thermal infrared wave,and also normalized difference vegetation index(NDVI) was calculated.NDVI of the study area on June 23,1988,May 6,2007,and May 10,2000 was respectively obtained by using Band Math,the least square fitting was adopted to simulate the correlation between surface temperature and vegetation cover.Moreover,linear regression analysis of the correlation between vegetation cover and NDVI was carried out in Excel.The results showed that(a) most of the constructed area has a low NDVI value because there are large areas of hard surface such as buildings and roads,but less vegetation cover;(b) the quarters with better vegetation cover have higher NDVI values;the Tuojiang River has a negative NDVI value;rural areas have better vegetation cover and higher NDVI values.Brightness temperature and vegetation cover has distinct negative correlation,specifically,the higher the vegetation cover is,the lower the surface temperature is,and vice versa. 展开更多
关键词 Urban heat ISLAND effects Remote sensing(RS) brightNESS temperature Normalized difference VEGETATION index(NDVI) CORRELATION ANALYSIS
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肝细胞癌患者外周血CD3bright T细胞CD27与PD1表达的应用研究 被引量:1
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作者 金方方 刘宁 +3 位作者 严艳 金子铮 文凤 娄金丽 《北京医学》 CAS 2019年第6期460-463,共4页
通过对肝细胞癌(hepatocellular carcinoma, HCC )>者外周血CD3高表达T细胞(CD3brightT细胞)表型特点与治疗前后细胞CD27.PD1表达变化的分析,探讨CD3brightT细胞在肝癌进展中的临床意义。方法选取2018年9月至2019年2月首都医科大学... 通过对肝细胞癌(hepatocellular carcinoma, HCC )>者外周血CD3高表达T细胞(CD3brightT细胞)表型特点与治疗前后细胞CD27.PD1表达变化的分析,探讨CD3brightT细胞在肝癌进展中的临床意义。方法选取2018年9月至2019年2月首都医科大学附属北京佑安医院CD3bnght T细胞阳性的原发性HCC患者23例为HCC组,收集患者术前与术后1个月时临床当天检测剩余的全血标本,同时收集健康人30例为对照组,在流式细胞平台上进行CD3brightT细胞的T细胞受体类型、CD27分子与PD1表达水平的检测,同时收集患者临床资料用于统计学分析。结果CD3bright T细胞主要为述T细胞.HCC组及对照组中T细胞受体(T cell receptor, TCR)表型一致,与丫应细胞呈显著正相关(r= 0.938,P< 0.01 );HCC组外周血CD3bright T细胞主要为CD27阴性,CD3bright CD27*T细胞比例显著低于CD27阳性的CD3*T细胞和CD4-T细胞,差异有统计学意义(P< 0.05);HCC组CD3bright CD27,T细胞比例显著低于对照组(P<0.05),CD3bright PD1-T细胞显著髙于对照组,差异有统计学意义(P< 0.05);HCC组治疗前后,常规T细胞CD27与PD1的表达水平无明显变化,CD3bright CD27-T细胞和CD3bright PDPT细胞在术后水平均显著升高,差异有统计学意义(P<0.05)o结论CD3bright T细胞主要为yST细胞,与-y6T细胞呈显著正相关,可在一定程度上反映外周血y$T细胞的水平。HCC患者外周血中,常规T细胞主要为CD27*T细胞,CD3brightT细胞主要表现为CD27阴性。CD3bright CD27,T细胞和CD3bright PD1-T细胞水平在肝癌术后显著上升,细胞活性及功能发生变化,影响HCC的进展与预后。 展开更多
关键词 肝细胞癌 CD3bright T细胞 CD27 PD 1
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Comparison of the Bright Band Characteristics Measured by Micro Rain Radar (MRR) at a Mountain and a Coastal Site in South Korea 被引量:8
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作者 Joo-Wan CHA Ki-Ho CHANG +1 位作者 Seong Soo YUM Young-Jean CHOI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第2期211-221,共11页
Data from a long term measurement of Micro Rain Radar (MRR) at a mountain site (Daegwallyeong, DG, one year period of 2005) and a coastal site (Haenam, HN, three years 2004-2006) in South Korea were analyzed to ... Data from a long term measurement of Micro Rain Radar (MRR) at a mountain site (Daegwallyeong, DG, one year period of 2005) and a coastal site (Haenam, HN, three years 2004-2006) in South Korea were analyzed to compare the MRR measured bright band characteristics of stratiform precipitation at the two sites. On average, the bright band was somewhat thicker and the sharpness (average gradient of reflectivity above and below the reflectivity peak) was slightly weaker at DG, compared to those values at HN. The peak reflectivity itself was twice as strong and the relative location of the peak reflectivity within the bright band was higher at HN than at DG. Importantly, the variability of these values was much larger at HN than at DG. The key parameter to cause these differences is suggested to be the difference of the snow particle densities at the two sites, which is related to the degree of riming. Therefore, it is speculated that the cloud microphysical processes at HN may have varied significantly from un-rimed snow growth, producing low density snow particles, to the riming of higher density particles, while snow particle growth at DG was more consistently affected by the riming process, and therefore high density snow particles. Forced uplifting of cloudy air over the mountain area around DG might have resulted in an orographic supercooling effect that led to the enhanced riming of supercooled cloud drops. 展开更多
关键词 Micro Rain Radar bright band thickness and sharpness cloud microphysical processes local characteristics
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Color-stable,reduced efficiency roll-off hybrid white organic light emitting diodes with ultra high brightness 被引量:4
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作者 刘佰全 陶洪 +4 位作者 苏跃举 高栋雨 兰林锋 邹建华 彭俊彪 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第7期450-453,共4页
High-brightness and color-stable two-wavelength hybrid white organic light emitting diodes (HWOLEDs) with the configuration of indium tin oxide (ITO)/ N, N, N, N-tetrakis(4-methoxyphenyl)-benzidine (MeO-TPD):... High-brightness and color-stable two-wavelength hybrid white organic light emitting diodes (HWOLEDs) with the configuration of indium tin oxide (ITO)/ N, N, N, N-tetrakis(4-methoxyphenyl)-benzidine (MeO-TPD): tetrafluoro-tetracyanoqino dimethane (F4-TCNQ)/N,N-di(naphthalene-1-yl)-N,N-diphenyl-benzidine (NPB)/ 4,4-N,N-dicarbazolebiphenyl (CBP): iridium (III) diazine complexes (MPPZ) 2 Ir(acac)/NPB/2-methyl-9,10-di(2-naphthyl)anthracene (MADN): p-bis(p-N,N-di-phenyl-aminostyryl)benzene (DSA-ph)/bis(10-hydroxybenzo[h] quino-linato)beryllium complex (Bebq2)/LiF/Al have been fabricated and characterized. The optimal brightness of the device is 69932 cd/m2 at a voltage of 13 V, and the Commission Internationale de l’Eclairage (CIE) chromaticity coordinates are almost constant during a large voltage change of 6–12 V. Furthermore, a current efficiency of 15.3 cd/A at an illumination-relevant brightness of 1000 cd/m2 is obtained, which rolls off slightly to 13.0 cd/A at an ultra high brightness of 50000 cd/m2. We attribute this great performance to wisely selecting an appropriate spacer together with effectively utilizing the combinations of exciton-harvested orange-phosphorescence/blue-fluorescence in the device. Undoubtedly, this is one of the most exciting results in two-wavelength HWOLEDs up to now. 展开更多
关键词 white light color stability efficiency roll-off high brightness
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Comparative Analysis of Microwave Brightness Temperature Data in Northeast China Using AMSR-E and MWRI Products 被引量:7
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作者 GU Lingjia ZHAO Kai +1 位作者 ZHANG Shuwen ZHANG Shuang 《Chinese Geographical Science》 SCIE CSCD 2011年第1期84-93,共10页
With such significant advantages as all-day observation, penetrability and all-weather coverage, passive mi-crowave remote sensing technique has been widely applied in the research of global environmental change. As t... With such significant advantages as all-day observation, penetrability and all-weather coverage, passive mi-crowave remote sensing technique has been widely applied in the research of global environmental change. As the sat-ellite-based passive microwave remote sensor, the Advanced Microwave Scanning Radiometer-Earth Observing Sys-tem (AMSR-E) loaded on NASA's (National Aeronautics and Space Administration of USA) Aqua satellite has been popularly used in the field of microwave observation. The Microwave Radiation Imager (MWRI) loaded on the Chi-nese FengYun-3A (FY-3A) satellite is an AMSR-E-like conical scanning microwave sensor, but there are few reports about MWRI data. This paper firstly proposed an optimal spatial position matching algorithm from rough to exact for the position matching between AMSR-E and MWRI data, then taking Northeast China as an example, comparatively analyzed the microwave brightness temperature data derived from AMSR-E and MWRI. The results show that when the antenna footprints of the two sensors are filled with either full water, or full land, or mixed land and water with ap-proximate proportion, the errors of brightness temperature between AMSR-E and MWRI are usually in the range from -10 K to +10 K. In general, the residual values of brightness temperature between the two microwave sensors with the same spatial resolution are in the range of ±3 K. Because the spatial resolution of AMSR-E is three times as high as that of MWRI, the results indicate that the quality of MWRI data is better. The research can provide useful information for the MWRI data application and microwave unmixing method in the future. 展开更多
关键词 AMSR-E MWRI FY-3A satellite brightness temperature spatial resolution spatial position matching Northeast China
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