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Inhibitory Effects of Ginsenoside Rb1 on Apoptosis Caused by HSV-1 in Human Glioma Cells 被引量:5
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作者 Yuan-Yuan Liang Bin Wang +4 位作者 Dong-Meng Qian Ling Li Zhi-Hao Wang ming hu Xu-Xia Song 《Virologica Sinica》 CAS CSCD 2012年第1期19-25,共7页
To investigate the inhibitory effects of Ginsenoside Rb1 (GRb1) on apoptosis caused by Herpes Simplex Virus-1(HSV-1) in Human Glioma Cells (U251), U251 cells were infected by HSV-1 at a multiplicity of infection of 5 ... To investigate the inhibitory effects of Ginsenoside Rb1 (GRb1) on apoptosis caused by Herpes Simplex Virus-1(HSV-1) in Human Glioma Cells (U251), U251 cells were infected by HSV-1 at a multiplicity of infection of 5 and GRb1, GRb1+HSV-1, HSV-1 and control groups. MTT and cell apoptosis assays were used to detect the inhibitory effects of GRb1 on the apoptosis of U251 cells that caused by HSV-1 infection for various concentrations of drug and virus treatments by MTT assay. We found that in the 400 μg/mL GRb1 and 400 μg/mL GRb1+HSV-1 groups, MTT values were higher than control group at all times (P<0. 05). Moreover, the apoptosis rate in the 400 μg/mL GRb1+HSV-1 group was lower than the HSV-1 group (P<0. 05). These results confirmed that, at appropriate concentrations, GRb1 could inhibit nerve cell apoptosis in HSV-1 infections. 展开更多
关键词 神经细胞凋亡 人参皂甙RBL HSV-1 抑制作用 脑胶质瘤 U251细胞 多重感染 MTT法
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An Interval-parameter Fuzzy Robust Nonlinear Programming Model for Water Quality Management
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作者 Min Liu Guoxin Nie +2 位作者 ming hu Renfei Liao Yangshuo Shen 《Journal of Water Resource and Protection》 2013年第1期12-16,共5页
Planning for water quality management is important for facilitating sustainable socio-economic development;however, the planning is also complicated by a variety of uncertainties and nonlinearities. In this study, an ... Planning for water quality management is important for facilitating sustainable socio-economic development;however, the planning is also complicated by a variety of uncertainties and nonlinearities. In this study, an interval-parameter fuzzy robust nonlinear programming (IFRNP) model was developed for water quality management to deal with such difficulties. The developed model incorporated interval nonlinear programming (INP) and fuzzy robust programming (FRP) methods within a general optimization framework. The developed IFRNP model not only could explicitly deal with uncertainties represented as discrete interval numbers and fuzzy membership functions, but also was able to deal with nonlinearities in the objective function. 展开更多
关键词 Water Quality Management INTERVAL PROGRAMMING FUZZY ROBUST PROGRAMMING Nonlinear PROGRAMMING UNCERTAINTY
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Liver Tumor Segmentation Based on Multi-Scale and Self-Attention Mechanism
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作者 Fufang Li Manlin Luo +2 位作者 ming hu Guobin Wang Yan Chen 《Computer Systems Science & Engineering》 SCIE EI 2023年第12期2835-2850,共16页
Liver cancer has the second highest incidence rate among all types of malignant tumors,and currently,its diagnosis heavily depends on doctors’manual labeling of CT scan images,a process that is time-consuming and sus... Liver cancer has the second highest incidence rate among all types of malignant tumors,and currently,its diagnosis heavily depends on doctors’manual labeling of CT scan images,a process that is time-consuming and susceptible to subjective errors.To address the aforementioned issues,we propose an automatic segmentation model for liver and tumors called Res2Swin Unet,which is based on the Unet architecture.The model combines Attention-Res2 and Swin Transformer modules for liver and tumor segmentation,respectively.Attention-Res2 merges multiple feature map parts with an Attention gate via skip connections,while Swin Transformer captures long-range dependencies and models the input globally.And the model uses deep supervision and a hybrid loss function for faster convergence.On the LiTS2017 dataset,it achieves better segmentation performance than other models,with an average Dice coefficient of 97.0%for liver segmentation and 81.2%for tumor segmentation. 展开更多
关键词 Liver and tumor segmentation unet attention gate swin transformer deep supervision hybrid loss function
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淫羊藿黄酮类化合物的大鼠在体肠吸收研究 被引量:39
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作者 赵艳红 贾晓斌 +2 位作者 陈彦 范晨怡 ming hu 《中国药学杂志》 CAS CSCD 北大核心 2008年第3期188-191,共4页
目的研究淫羊藿中黄酮类化合物在大鼠各肠段的吸收动力学特征。方法采用大鼠在体肠灌流模型对淫羊藿苷和淫羊藿总黄酮在大鼠各肠段的吸收特性进行研究。结果淫羊藿苷在大鼠各肠段的渗透系数按空肠、十二指肠、回肠、结肠顺序依次分别为(... 目的研究淫羊藿中黄酮类化合物在大鼠各肠段的吸收动力学特征。方法采用大鼠在体肠灌流模型对淫羊藿苷和淫羊藿总黄酮在大鼠各肠段的吸收特性进行研究。结果淫羊藿苷在大鼠各肠段的渗透系数按空肠、十二指肠、回肠、结肠顺序依次分别为(5.25±0.17),(4.27±0.28),(1.99±0.09),(0.80±0.03);淫羊藿总黄酮中淫羊藿苷在大鼠各肠段的渗透系数按空肠、十二指肠、回肠、结肠顺序依次分别为(3.65±0.18),(4.68±0.17),(1.64±0.08),(0.58±0.26)。结论淫羊藿总黄酮中有多种成分在大鼠肠段会发生代谢转化,其中淫羊藿苷经过大鼠肠段后代谢最为明显。 展开更多
关键词 淫羊藿苷 淫羊藿总黄酮 吸收动力学 在体肠灌流模型
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在体肠灌流模型及其在中药研究中的应用 被引量:36
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作者 谭晓斌 贾晓斌 +1 位作者 陈彦 ming hu 《中成药》 CAS CSCD 北大核心 2007年第11期1665-1668,共4页
关键词 吸收 在体肠单向灌流模型 中药 复方配伍
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Caco-2细胞模型及其对黄酮类成分作用机制研究进展 被引量:12
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作者 赵艳红 贾晓斌 +1 位作者 陈彦 ming hu 《中草药》 CAS CSCD 北大核心 2007年第6期938-941,共4页
Caco-2细胞模型作为ADME/Tox研究平台中肠吸收模型之一,已广泛用于药物动力学研究,可通过体外试验预测药物在体内的吸收和代谢,阐明药物在体内的吸收机制、毒性、药物吸收过程中的相互作用、药物的化学结构和体内转运关系以及药物代谢... Caco-2细胞模型作为ADME/Tox研究平台中肠吸收模型之一,已广泛用于药物动力学研究,可通过体外试验预测药物在体内的吸收和代谢,阐明药物在体内的吸收机制、毒性、药物吸收过程中的相互作用、药物的化学结构和体内转运关系以及药物代谢稳定性等。以黄酮类成分为代表,介绍Caco-2细胞模型在中药有效成分吸收代谢机制研究方面的应用进展。 展开更多
关键词 CACO-2细胞模型 ADME/Tox 黄酮类化合物 吸收 代谢
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淫羊藿苷大鼠在体肠吸收动力学的研究 被引量:16
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作者 赵艳红 贾晓斌 +1 位作者 陈彦 ming hu 《中华中医药杂志》 CAS CSCD 北大核心 2007年第10期681-684,共4页
目的:研究淫羊藿苷在大鼠各肠段的吸收动力学特征。方法:采用大鼠在体肠灌流模型对淫羊藿苷在大鼠各肠段的吸收特性进行研究。结果:淫羊藿苷在大鼠各肠段的渗透系数按空肠、十二指肠、回肠、结肠顺序依次分别为(5.25±0.17)、(4.27&... 目的:研究淫羊藿苷在大鼠各肠段的吸收动力学特征。方法:采用大鼠在体肠灌流模型对淫羊藿苷在大鼠各肠段的吸收特性进行研究。结果:淫羊藿苷在大鼠各肠段的渗透系数按空肠、十二指肠、回肠、结肠顺序依次分别为(5.25±0.17)、(4.27±0.28)、(1.99±0.09)、(0.80±0.03),各肠段均能检测到淫羊藿次苷。结论:淫羊藿苷在大鼠肠段代谢成淫羊藿次苷后被吸收。 展开更多
关键词 淫羊藿苷 吸收动力学 在体肠灌流模型 实验研究
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程序化达芬奇机器人“3+2”模式“七步法”远端胃癌根治术 被引量:6
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作者 黄显斌 狐鸣 +3 位作者 蔡辉 詹渭鹏 杨婧 马云涛 《中国肿瘤临床》 CAS CSCD 北大核心 2022年第3期124-128,共5页
目的:介绍程序化达芬奇机器人“3+2”模式远端胃癌根治手术清扫“七步法”。方法:回顾性分析2017年6月至2020年6月于甘肃省人民医院完成全腔镜下达芬奇机器人远端胃癌根治术的患者100例。手术分七步:1)建立戳孔,腹腔探查,悬调肝脏,摆体... 目的:介绍程序化达芬奇机器人“3+2”模式远端胃癌根治手术清扫“七步法”。方法:回顾性分析2017年6月至2020年6月于甘肃省人民医院完成全腔镜下达芬奇机器人远端胃癌根治术的患者100例。手术分七步:1)建立戳孔,腹腔探查,悬调肝脏,摆体位,连接机器;2)右侧大弯侧区域及幽门下区域(4d,6);3)幽门上区域,离断十二指肠,清扫肝十二指肠韧带(5,12a);4)胰腺前方区域(7,8a,8p,9,11p);5)小弯侧区域(1,3);6)左侧胃大弯区域(4sb);7)离断胃标本,近端胃和空肠吻合。结果:全部患者无中转开腹,术中无输血。手术时间(175.0±16)min,出血量(99±36.4)mL,淋巴结清扫数目(30.3±2.5)枚,机器人相关费用(22794±3660)元。并发症发生5例,其中肠梗阻2例,腹腔内出血1例、伤口感染1例以及胃排空延迟1例,均采用保守方法治愈。未出现吻合口狭窄及吻合口瘘。结论:本程序化方法安全可行,重复性好,手术时间相对较短,费用相对较低。该程序化方法有利于新开展机器人手术的机构培养手术团队、缩短学习曲线、降低手术难度,从而更好地服务于临床教学工作。 展开更多
关键词 达芬奇手术机器人 远端胃癌根治术 程序化方法
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基于Grimm180粒子仪对塔克拉玛干沙漠沙尘暴的定量观测 被引量:2
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作者 明虎 王敏仲 +1 位作者 刘新春 杨慧娟 《沙漠与绿洲气象》 2021年第2期26-33,共8页
为了得到沙尘粒子和沙尘质量浓度的实时定量特征,利用Grimm180粒子仪在塔克拉玛干沙漠对沙尘暴进行了实时观测。通过分析Grimm180粒子仪在2018年5月20日和24日两次沙尘暴过程观测的数据得到:在浮尘、扬沙和沙尘暴期间,PM_(2.5)的质量浓... 为了得到沙尘粒子和沙尘质量浓度的实时定量特征,利用Grimm180粒子仪在塔克拉玛干沙漠对沙尘暴进行了实时观测。通过分析Grimm180粒子仪在2018年5月20日和24日两次沙尘暴过程观测的数据得到:在浮尘、扬沙和沙尘暴期间,PM_(2.5)的质量浓度值随时间变化不大,一般PM_(2.5)浓度值<1500μg·m^(-3),而PM_(10)在不同阶段的变化比较明显,数值在2000~6000μg·m^(-3)。沙尘粒子谱和沙尘质量浓度谱的分布形状在浮尘、扬沙和沙尘暴基本相同,当粒子直径>0.35μm时,粒子数浓度随直径的增大近似符合M-P分布。从浮尘到扬沙再到沙尘暴,小粒子区(D≤1μm)的占比越来越小,而中粒子区(1μm10μm)的粒子数越来越多并且占比越来越大。当粒子直径为0.35μm左右时,粒子数浓度达到最大值;当粒子直径在25~32μm时,沙尘质量浓度的值最大。在浮尘和扬沙阶段,PM_(2.5)/PM_(10)>25%;每分钟1 L体积内的沙尘粒子总数大约是4×10^(5),最大沙尘质量浓度<20μg·L^(-1)。在沙尘暴阶段,PM_(2.5)/PM_(10)<15%;每分钟1 L体积内的沙尘粒子总数>5×10^(5),最大沙尘质量浓度>25μg·L^(-1)。这些结论为准确地分析沙尘暴的定量特征提供了科学依据。 展开更多
关键词 沙尘粒子谱 沙尘质量浓度 Grimm180粒子仪 塔克拉玛干沙漠
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Comparative study of visual acuity and aberrations after intralase femtosecond LASIK:small corneal flap versus big corneal flap 被引量:4
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作者 Ya-Li Zhang Lei Liu +5 位作者 Chang-Xia Cui ming hu Zhao-Na Li Li-Jun Cao Xiu-hua Jing Guo-Ying Mu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2013年第5期641-645,共5页
AIM:To study the effects of different flap sizes on visual acuity,refractive outcomes,and aberrations after femtosecond laser for laser in situ keratomileusis(LASIK).METHODS:In each of the forty patients enrolled,1 ey... AIM:To study the effects of different flap sizes on visual acuity,refractive outcomes,and aberrations after femtosecond laser for laser in situ keratomileusis(LASIK).METHODS:In each of the forty patients enrolled,1 eye was randomly assigned to receive treatment with a 8.1mm diameter corneal flap,defined as the small flap,while the other eye was treated with a 8.6mm diameter corneal flap,defined as the big flap.Refractive errors,visual acuity,and higher-order aberrations were compared between the two groups at week 1,month 1 and 3 postoperatively. RESULTS:The postoperative refractive errors and visual acuity all conformed to the intended goal.Postoperative higher-order aberrations were increased,especially in spherical aberration(Z12) and vertical coma(Z7).There were no statistically significant differences between the two groups in terms of postoperative refractive errors,visual acuity,root mean square of total HOAs(HO-RMS),trefoil 30°(Z6),vertical coma(Z7),horizontal coma(Z8),trefoil 0°(Z9),and spherical aberration(Z12) at any point during the postoperative follow-up.CONCLUSION:Both the small and big flaps are safe and effective procedures to correct myopia,provided the exposure stroma meets the excimer laser ablations.The personalized size corneal flap is feasible,as we can design the size of corneal flap based on the principle that the corneal flap diameter should be equal to or greater than the sum of the maximum ablation diameter and apparatus error. 展开更多
关键词 femtosecond laser laser in situ keratomileusis refractive surgery FLAP visual acuity ABERRATION
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Extracorporeal Membrane Oxygenation Therapy for Critically Ill Coronavirus Disease 2019 Patients in Wuhan,China:A Retrospective Multicenter Cohort Study 被引量:2
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作者 Jing FANG Rui LI +18 位作者 Yue CHEN Juan-juan QIN ming hu Chao-lin huANG Lin CHENG Yi HE Yi LI Qiang ZHOU Dai-xing ZHOU Fei huANG Fang LEI Bo YANG Jun CHEN Hong-ping DENG Yu-feng YUAN Jia-hong XIA Song WAN Hong-liang LI Xiang WEI 《Current Medical Science》 SCIE CAS 2021年第1期1-13,共13页
Currently,little in-depth evidence is known about the application of extracorporeal membrane oxygenation(ECMO)therapy in coronavirus disease 2019(COVID-19)patients.This retrospective multicenter cohort study included ... Currently,little in-depth evidence is known about the application of extracorporeal membrane oxygenation(ECMO)therapy in coronavirus disease 2019(COVID-19)patients.This retrospective multicenter cohort study included patients with COVID-19 at 7 designated hospitals in Wuhan,China.The patients were followed up until June 30,2020.Univariate and multivariate logistic regression analyses were performed to identify the risk factors associated with unsuccessful ECMO weaning.Propensity score matching was used to match patients who received veno-venous ECMO with those who received invasive mechanical ventilation(IMV)-only therapy.Of 88 patients receiving ECMO therapy,27 and 61 patients were and were not successfully weaned from ECMO,respectively.Additionally,15,15,and 65 patients were further weaned from IMV,discharged from hospital,or died during hospitalization,respectively.In the multivariate logistic regression analysis,a lymphocyte count≤0.5×10^(9)/L and D-dimer concentration>4×the upper limit of normal level at ICU admission,a peak PaCO_(2)>60 mmHg at 24 h before ECMO initiation,and no tracheotomy performed during the ICU stay were independently associated with lower odds of ECMO weaning.In the propensity scorematched analysis,a mixed-effect Cox model detected a lower hazard ratio for 120-day all-cause mortality after ICU admission during hospitalization in the ECMO group.The presence of lymphocytopenia,higher D-dimer concentrations at ICU admission and hypercapnia before ECMO initiation could help to identify patients with a poor prognosis.Tracheotomy could facilitate weaning from ECMO.ECMO relative to IMV-only therapy was associated with improved outcomes in critically ill COVID-19 patients. 展开更多
关键词 coronavirus disease 2019 extracorporeal membrane oxygenation mechanical ventilation acute respiratory distress syndrome viral pneumonia
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Temporal and spatial distribution of metabotropic glutamate receptor 5 during development in the rat cortex and hippocampus 被引量:1
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作者 Xinli Xiao ming hu +3 位作者 Pengbo Yang Lin Zhang Xinlin Chen Yong Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第17期1296-1300,共5页
Metabotropic glutamate receptor 5 (mGluR5) is expressed by neurons in zones of active neurogenesis and is involved in the development of neural stem cells in vivo and in vitro. We examined the expression of mGluR5 i... Metabotropic glutamate receptor 5 (mGluR5) is expressed by neurons in zones of active neurogenesis and is involved in the development of neural stem cells in vivo and in vitro. We examined the expression of mGluR5 in the cortex and hippocampus of rats during various prenatal and postnatal periods using immunohistochemistry. During prenatal development, mGluR5 was pdmadly localized to neuronal somas in the forebrain. During early postnatal periods, the receptor was mainly present on somas in the cortex, mGluR5 immunostaining was visible in apical dendrites and in the neuropil of neurons and persisted throughout postnatal development. During this period, pyramidal neurons were strongly labeled for the receptor. In the hippocampal CA1 region, mGluR5 immunoreactivity was more intense in the stratum oriens, stratum radiatum, and lacunosum moleculare at P0, P5 and P10 relative to P60. mGluR5 expression increased significantly in the molecular layer and decreased significantly in the granule cell layer of the dentate gyrus at P5, P10 and P60 in comparison with P0. Furthermore, some mGluR5-positive cells were also bromodeoxyuridine- or NeuroD-positive in the dentate gyrus at P14. These results demonstrate that mGluR5 has a differential expression pattern in the cortex and hippocampus during early growth, suggesting a role for this receptor in the control of domain specific brain developmental events. 展开更多
关键词 metabotropic glutamate receptor 5 CORTEX HIPPOCAMPUS brain development RAT neural regeneration
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The Impact of Satellite Radiance Data Assimilation within a Frequently Updated Regional Forecast System Using a GSI-based Ensemble Kalman Filter 被引量:1
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作者 Kefeng Zhu ming XUE +4 位作者 Yujie PAN ming hu Stanley G. BENJAMIN Stephen S. WEYGANDT Haidao LIN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第12期1308-1326,共19页
A regional ensemble Kalman filter (EnKF) data assimilation (DA) and forecast system was recently established based on the Gridpoint Statistical Interpolation (GSI) analysis system. The EnKF DA system was tested with c... A regional ensemble Kalman filter (EnKF) data assimilation (DA) and forecast system was recently established based on the Gridpoint Statistical Interpolation (GSI) analysis system. The EnKF DA system was tested with continuous threehourly updated cycles followed by 18-h deterministic forecasts from every three-hourly ensemble mean analysis. Initial tests showed negative to neutral impacts of assimilating satellite radiance data due to the improper bias correction procedure. In this study, two bias correction schemes within the established EnKF DA system are investigated and the impact of assimilating additional polar-orbiting satellite radiance is also investigated. Two group experiments are conducted. The purpose of the first group is to evaluate the bias correction procedure. Two online bias correction methods based on GSI 3DVar and EnKF algorithms are used to assimilate AMSU-A radiance data. Results show that both variational and EnKF-based bias correction procedures effectively reduce the observation and background radiance differences, achieving positive impacts on forecasts. With proper bias correction, we assimilate full radiance observations including AMSU-A, AMSU-B, AIRS, HIRS3/4, and MHS in the second group. The relative percentage improvements (RPIs) for all forecast variables compared to those without radiance data assimilation are mostly positive, with the RPI of upper-air relative humidity being the largest. Additionally, precipitation forecasts on a downscaled 13-km grid from 40-km EnKF analyses are also improved by radiance assimilation for almost all forecast hours. 展开更多
关键词 SATELLITE RADIANCE ASSIMILATION ENKF BIAS correction
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Bilateral maxillary fused second and third molars:a rare occurrence 被引量:1
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作者 Rui-Zhen Liang Jin-Tao Wu +4 位作者 You-Nong Wu Roger J Smales ming hu Jin-hua Yu Guang-Dong Zhang 《International Journal of Oral Science》 SCIE CAS CSCD 2012年第4期231-234,共4页
This case report describes the diagnosis and endodontic therapy of maxillary fused second and third molars, using cone-beam computed tomography (CBCT). A 31-year-old Chinese male, with no contributory medical or fam... This case report describes the diagnosis and endodontic therapy of maxillary fused second and third molars, using cone-beam computed tomography (CBCT). A 31-year-old Chinese male, with no contributory medical or family/social history, presented with throbbing pain in the maxillary right molar area following an unsuccessful attempted tooth extraction. Clinical examination revealed what appeared initially to be a damaged large extra cusp on the buccal aspect of the distobuccal cusp of the second molar. However, CBCT revealed that a third molar was fused to the second molar. Unexpectedly, the maxillary left third molar also was fused to the second molar, and the crown of an unerupted supernumerary fourth molar was possibly also fused to the apical root region of the second molar. Operative procedures should not be attempted without adequate radiographic investigation. CBCT allowed the precise location of the root canals of the right maxillary fused molar teeth to permit successful endodontic therapy, confirmed after 6 months. 展开更多
关键词 cone-beam computed tomography scans endodontic therapy fusion of teeth maxillary molar
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Effect of cenospheres addition on microstructure and properties of AZ91D alloy 被引量:1
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作者 Zhi-qiu huang Si-rong Yu +3 位作者 ming hu Ying-chun Shi Liu-yan Li Guo-yan Bo 《China Foundry》 SCIE 2015年第6期406-411,共6页
The cenospheres/AZ91D composites were fabricated by melt stir method. The phases, microstructure and tensile fracture morphology of the composites were analyzed using XRD, Olympus metallurgical microscopy and SEM meth... The cenospheres/AZ91D composites were fabricated by melt stir method. The phases, microstructure and tensile fracture morphology of the composites were analyzed using XRD, Olympus metallurgical microscopy and SEM methods. The thermal expansion coefficient(CTE) and tensile properties were measured. The results showed that the cenospheres distribute uniformly in the Mg alloy matrix and refine the matrix microstructure. Mg2 Si and MgO were found in addition to α-Mg and β-Mg17Al12 phases using XRD. The CTE of the composites reduced after the cenospheres are added. The yield strength of the composites increases significantly with an increase in the mass fraction and a decrease in the size of the cenospheres. The tensile strength of the composites achieves maximum when the mass fraction of cenospheres is 9wt.% and the size of cenospheres is 80 μm. The fracture mechanism of the composites is cleavage fracture. 展开更多
关键词 cenospheres/AZ91D MICROSTRUCTURE thermal expansion coefficient tensile strength
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Detecting sand-dust storms using a wind-profiling radar 被引量:2
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作者 WANG Minzhong ming hu +3 位作者 huO Wen XU Hongxiong LI Jiangang LI Xingcai 《Journal of Arid Land》 SCIE CSCD 2017年第5期753-762,共10页
Sand-dust storm is a type of disastrous weather, typically occurring in arid and semi-arid climates. This study selected a region in the hinterlands of the Taklimakan Desert, called the Tazhong region, as the experime... Sand-dust storm is a type of disastrous weather, typically occurring in arid and semi-arid climates. This study selected a region in the hinterlands of the Taklimakan Desert, called the Tazhong region, as the experimental area to quantitatively estimate the particle concentrations of sand-dust storms using the boundary layer wind-profiling radar. We thoroughly studied the radar echo signals and reflectivity factor features during the sand-dust storms. The results indicate that(1) under sand-dust storm conditions, boundary layer wind-profiling radar cannot capture the complete information regarding horizontal wind velocity and direction, but it can obtain the backscattering intensity of sand-dust storms; and(2) during sand-dust storms particle size distributions in the surface layer closely resemble log-normal distributions, with sand-dust particles sizes of 90–100 μm accounting for the maximum particle probability. Retrieved particle size distributions at heights of 600, 800, and 1000 m follow log-normal distributions, and the expected value of particle diameter decreases gradually with increasing height. From the perspective of orders of magnitude, the retrieved results for particle number concentrations and mass concentrations are consistent with previous aircraft-detected results, indicating that it is basically feasible to use boundary layer wind-profiling radar to quantitatively detect the particle concentrations of dust storms. 展开更多
关键词 echo signal mass concentration retrieval method sand-dust storm wind-profiling radar Taklimakan Desert
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Calculation and Inspection of Alloy Design of Cr-W- Mo-V High Alloy Steel Addition Niobium for Machinery Knives 被引量:1
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作者 Yongqing Ma ming hu 《材料科学研究(中英文版)》 2015年第1期8-14,共7页
关键词 设计计算 高合金钢 合金设计 机械刀具 钒合金 微量铌 钨钼 MC碳化物
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Inhibitory effect of polysulfated heparin endostatin on alkali burn induced corneal neovascularization in rabbits
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作者 Zhao-Na Li Zhong-Fang Yuan +5 位作者 Guo-Ying Mu ming hu Li-Jun Cao Ya-Li Zhang Lei Liu ming-Xu Ge 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第2期234-238,共5页
AIM: To investigate anti-angiogenic effects of polysulfated heparin endostatin(PSH-ES) on alkali burn induced corneal neovascularization(NV) in rabbits.METHODS: An alkali burn was made on rabbit corneas to induce corn... AIM: To investigate anti-angiogenic effects of polysulfated heparin endostatin(PSH-ES) on alkali burn induced corneal neovascularization(NV) in rabbits.METHODS: An alkali burn was made on rabbit corneas to induce corneal NV in the right eye of 24 rabbits. One day after burn creation, a 0.2 m L subconjunctival injection of 50 μg/m L PSH-ES, 50 μg/m L recombinant endostatin(ES), or normal saline was administered every other day for a total of 14d(7 injections). Histology and immunohistochemisty were used to examine corneas.Corneal NV growth was evaluated as microvessel quantity and corneal vascular endothelial growth factor(VEGF)expression was measured by immunohistochemical assay.RESULTS: Subconjunctival injection of ES and PSHES resulted in significant corneal NV suppression, but PSH-ES had a more powerful anti-angiogenic effect than ES. Mean VEGF concentration in PSH-ES treated corneas was significantly lower than in ES treated and saline treated corneas. Histological examination showed that corneas treated with either PSH-ES or ES had significantly fewer microvessels than eyes treated with saline. Additionally corneas treated with PSH-ES had significantly fewer microvessels than corneas treated with ES.CONCLUSION: Both PSH-ES and recombinant ES effectively inhibit corneal NV induced by alkali burn.However, PSH-ES is a more powerful anti-angiogenic agent than ES. This research has the potential to provide a new treatment option for preventing and treating corneal NV. 展开更多
关键词 polysulfated heparin endostatin corneal neovascularization chemical burns RABBITS
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Modelling and analysis of circular bimorph piezoelectric actuator for deformable mirror
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作者 Hairen WANG ming hu Zhenqin LI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第5期639-646,共8页
A theoretical model of a circular flexure-mode piezoelectric bimorph ac- tuator is established. The circular bimorph structure, consisting of two flexible layers of piezoelectric material and a layer of metallic mater... A theoretical model of a circular flexure-mode piezoelectric bimorph ac- tuator is established. The circular bimorph structure, consisting of two flexible layers of piezoelectric material and a layer of metallic material in the middle, is powered to the flexural deformation. The analytical solutions including the statics solution and the dynamics solution are derived from the 3D equations of the linear theory of piezoelectric- ity. Numerical results are included to show the circular bimorph piezoelectric actuator (CBPA) performance, depending on the physical parameters. 展开更多
关键词 piezoelectric actuator circular bimorph structure flexure-mode
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Comparative study of visual acuity and aberrations after intralase femtosecond LASIK: small corneal flap versus big corneal flap 被引量:1
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作者 Ya-Li Zhang Lei Liu +5 位作者 Chang-Xia Cui ming hu Zhao-Na Li Li-Jun Cao Xiu-hua Jing Guo-Ying Mu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2014年第5期1-1,共5页
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