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Serum level changes of inflammatory cytokines in patients with moderate to severe acne vulgaris treated with dual-wavelength laser 被引量:1
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作者 Yang Liu Qilin Sun +2 位作者 Hui Xu gang ma Pinru Wu 《Chinese Journal of Plastic and Reconstructive Surgery》 2023年第2期47-52,共6页
Background:Acne vulgaris(AV)is a common inflammatory skin disease.Although various mechanisms have been indicated in the etiopathogenesis of AV,the exact pathophysiology remains unknown.Various lasers have been used t... Background:Acne vulgaris(AV)is a common inflammatory skin disease.Although various mechanisms have been indicated in the etiopathogenesis of AV,the exact pathophysiology remains unknown.Various lasers have been used to treat AV;however,the serum level changes of inflammatory cytokines after laser therapy have not been elucidated.We aimed to investigate the relationship between inflammatory changes and remission on the opposite side in patients with moderate to severe AV after treating half of the face with 595-and 1064-nm dualwavelength laser.Methods:In total,18 patients(9 male and 9 female)between 16 and 35 years of age with moderate to severe AV were evaluated in the study.Disease severity was classified according to the Pillsbury grading system of acne.Patients were randomized to receive a series of two treatment sessions at intervals of 2 weeks and followed up at 2 weeks after the final treatment.A 3 mL blood sample was drawn from every subject each time,and serum levels of inflammatory cytokines such as interleukin(IL)-6,IL-8,and IL-22 were determined using enzyme-linked immunosorbent assay at baseline and 2 weeks after each treatment.Improvement was determined by a blinded assessment of photographs taken before and after the final evaluation.Results:Inflammation was significantly reduced on both the treated and untreated sides,and symptoms of AV lesions were alleviated.All patients showed a significant increase in serum IL-22 levels after the first laser therapy,with no significant difference in serum IL-6 and IL-8 levels.After the second laser therapy,serum IL-6,IL-8,and IL-22 levels were significantly decreased.No significant side effects such as bruising,edema,hyperpigmentation,hypopigmentation,or scarring were reported.Conclusion:Half-face treatment with 595-and 1064-nm dual-wavelength laser for moderate and severe AV showed a significant effect of full-face remission,which was associated with a gradual decrease in IL-6,IL-8,and IL-22 levels after half-face topical treatment.This suggests that reducing inflammatory cytokine levels in the serum can relieve inflammation in non-therapeutic sites.This laser treatment is effective,economical,and painless. 展开更多
关键词 Acne vulgaris Dual-wavelength laser Inflammatory cytokines SERUM
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Long-term deformation analysis of Shuibuya concrete face rockfill dam based on response surface method and improved genetic algorithm 被引量:12
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作者 Fu-hai Yao Shao-heng Guan +4 位作者 He Yang Yuan Chen Huan-feng Qiu gang ma Qi-wen Liu 《Water Science and Engineering》 EI CAS CSCD 2019年第3期196-204,共9页
Due to the size effects of rockfill materials, the settlement difference between numerical simulation and in situ monitoring of rockfill dams is a topic of general concern.The constitutive model parameters obtained fr... Due to the size effects of rockfill materials, the settlement difference between numerical simulation and in situ monitoring of rockfill dams is a topic of general concern.The constitutive model parameters obtained from laboratory triaxial tests often underestimate the deformation of high rockfill dams.Therefore, constitutive model parameters obtained by back analysis were used to calculate and predict the long-term deformation of rockfill dams.Instead of using artificial neural networks (ANNs), the response surface method (RSM) was employed to replace the finite element simulation used in the optimization iteration.Only 27 training samples were required for RSM, improving computational efficiency compared with ANN, which required 300 training samples.RSM can be used to describe the relationship between the constitutive model parameters and dam settlements.The inversion results of the Shuibuya concrete face rockfill dam (CFRD) show that the calculated settlements agree with the measured data, indicating the accuracy and efficiency of RSM. 展开更多
关键词 SHUIBUYA ROCKFILL DAM Parameter BACK analysis Response surface method Duncan EB model TIME-DEPENDENT deformation
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常规超声联合超声造影鉴别诊断脉络膜转移癌和脉络膜血管瘤 被引量:1
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作者 马刚 洪林巍 +1 位作者 郭佩琦 崔煜艳 《国际眼科杂志》 CAS 北大核心 2023年第1期117-120,共4页
目的:分析脉络膜转移癌和脉络膜血管瘤的常规超声和超声造影(CEUS)特点,探讨常规超声联合CEUS在脉络膜转移癌和脉络膜血管瘤鉴别诊断中的临床应用价值。方法:回顾性分析2010-05/2016-01于沈阳市第四人民医院诊治的脉络膜转移癌患者17例1... 目的:分析脉络膜转移癌和脉络膜血管瘤的常规超声和超声造影(CEUS)特点,探讨常规超声联合CEUS在脉络膜转移癌和脉络膜血管瘤鉴别诊断中的临床应用价值。方法:回顾性分析2010-05/2016-01于沈阳市第四人民医院诊治的脉络膜转移癌患者17例17眼和脉络膜血管瘤患者35例35眼的常规超声和CEUS资料,常规超声观察肿瘤的二维和彩色多普勒特点,CEUS观察肿瘤的造影剂灌注强度和变化情况,并分析CEUS动态资料获得TI曲线和CEUS参数。结果:常规超声检查显示,脉络膜转移癌较脉络膜血管瘤回声偏低、欠均匀,隆起度较均匀一致,表面呈波浪状,其诊断脉络膜转移癌、脉络膜血管瘤的正确率分别为59%(10/17)、68%(24/35)。CEUS检查显示,脉络膜转移癌TI曲线类型多呈快进快出模式(14/17),脉络膜血管瘤TI曲线类型多呈快进慢出模式(31/35);脉络膜转移癌峰值强度(IMAX)、上升时间(RT)均低于脉络膜血管瘤(P<0.05)。常规超声联合CEUS诊断脉络膜转移癌、脉络膜血管瘤的正确率分别为82%(14/17)、88%(31/35)。结论:常规超声联合CEUS可为脉络膜转移癌和脉络膜血管瘤的鉴别诊断提供较为可靠的影像学依据,有助于两种肿瘤的早期定性诊断。 展开更多
关键词 超声 超声造影 脉络膜 脉络膜转移癌 脉络膜血管瘤
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Huge primary dedifferentiated pancreatic liposarcoma mimicking carcinosarcoma in a young female: A case report 被引量:1
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作者 Zhe Liu Wu-Feng Fan +3 位作者 Gui-Chen Li Jin Long Yuan-Hong Xu gang ma 《World Journal of Clinical Cases》 SCIE 2019年第11期1344-1350,共7页
BACKGROUND Pancreatic liposarcoma is a rare tumor. According to a literature review, the patient described in this study is the seventh case of pancreatic liposarcoma reported in the English literature and the third c... BACKGROUND Pancreatic liposarcoma is a rare tumor. According to a literature review, the patient described in this study is the seventh case of pancreatic liposarcoma reported in the English literature and the third case of dedifferentiated liposarcoma. Furthermore, this case had the largest primary tumor volume, and a primary pancreatic liposarcoma was diagnosed based on sufficient evidence. CASE SUMMARY We here report a rare case of a 28-year-old female with a huge dedifferentiated liposarcoma in the pancreatic tail. In June 2015, the patient underwent distal pancreatectomy with splenectomy. During the operation, a huge liposarcoma of approximately 28.0 cm × 19.0 cm × 8.0 cm was found, which had a yellow and white fish-like incisal surface. Based on both pathology and MDM2 gene amplification, the tumor was diagnosed as a dedifferentiated liposarcoma. The patient was treated with surgery but declined postoperative chemotherapy. She was well at the 26-mo follow-up, and no relapse was observed. CONCLUSION Pancreatic liposarcoma has a low incidence. Chemotherapy should be included in the treatment regimens. Complete resection is the only effective treatment. 展开更多
关键词 PANCREATIC LIPOSARCOMA Huge tumor DISTAL PANCREATECTOMY and SPLENECTOMY Chemotherapy Case report
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Differentiation and Pro-Angiogenic Potential of Infantile Hemangioma Stem Cells 被引量:2
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作者 Hanru YING Qianyi CHEN +7 位作者 Xuanfeng CHEN Zhang YU MD Shih-Jen CHANG Lei CHANG gang ma Yajing QIU Hui CHEN Xiaoxi LIN 《Chinese Journal of Plastic and Reconstructive Surgery》 2020年第1期25-34,共10页
Objectives Infantile hemangioma(IH)is defined as a benign vascular tumor composed of immature vascular endothelial cells,with the unique characteristics of rich vascularization and self-regression into fibro-fatty tis... Objectives Infantile hemangioma(IH)is defined as a benign vascular tumor composed of immature vascular endothelial cells,with the unique characteristics of rich vascularization and self-regression into fibro-fatty tissue.CD133-positive hemangioma stem cells(HemSCs),present in the proliferating IH tissue,can be used to establish the IH animal model,which has highlighted the pathogenesis of IH in recent years.This study focused on the biological characteristics and differentiation capacity of HemSCs and aimed to provide a theoretical possibility for its application in tissue engineering.Methods To further confirm our hypothesis,we used fluorescence-activated cell sorting(FACS),in vitro multipotent induced differentiation,angiogenesis assay,and antibody array to identify the surface markers,multipotent differential potential,angiogenesis potential,and secreted factors of HemSCs,respectively,utilizing human adipose stem cells(hADSCs)as the control.Results We successfully isolated and cultured HemSCs.FACS indicated that,on average,more than 80%of HemSCs matched the criteria of mesenchymal stem cell(MSC)surface markers.Our results confirmed that HemSCs could differentiate into adipocytes,osteocytes,and chondrocytes.Additionally,compared with fibroblasts or hADSCs,HemSCs could promote angiogenesis through para-secretion.Conclusions HemSCs may originate from normal MSCs,and owing to their powerful proliferative and angiogenic abilities,they could be considered an IH pathogenic factor.These characteristics demonstratet heir potential as a candidate seed cell in tissue engineering. 展开更多
关键词 INFANTILE HEMANGIOMA HEMANGIOMA STEM CELL ANGIOGENESIS MESENCHYMAL STEM CELL
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The Equitable Total Chromatic Number of Some Join graphs
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作者 gang ma Ming ma 《Open Journal of Applied Sciences》 2012年第4期96-99,共4页
A proper total-coloring of graph G is said to be?equitable if the number of elements (vertices and edges) in any?two color classes differ by at most one, which the required?minimum number of colors is called the equit... A proper total-coloring of graph G is said to be?equitable if the number of elements (vertices and edges) in any?two color classes differ by at most one, which the required?minimum number of colors is called the equitable total chromatic?number. In this paper, we prove some theorems on equitable?total coloring and derive the equitable total chromatic numbers?of Pm V?Sn, Pm V?Fn and Pm V Wn. 展开更多
关键词 JOIN GRAPH equitable TOTAL COLORING equitable TOTAL CHROMATIC NUMBERS
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Systemic Hemodynamic Changes in Low-Dose Ethanol Embolotherapy for Soft-Tissue Arteriovenous Malformations
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作者 Xi YANG Chen HUA +8 位作者 Hui CHEN Lan LUO gang ma Xiaojie HU YaJing QIU Wenxin YU Lei CHANG Yunbo JIN Xiaoxi LIN 《Chinese Journal of Plastic and Reconstructive Surgery》 2021年第1期32-40,共9页
Background Ethanol embolotherapy is considered an optimal choice for the treatment of arteriovenous malformations(AVMs);however,there are some complications associated with this treatment.This study aimed to prospecti... Background Ethanol embolotherapy is considered an optimal choice for the treatment of arteriovenous malformations(AVMs);however,there are some complications associated with this treatment.This study aimed to prospectively investigate systemic hemodynamic changes in high-flow AVMs using ethanol embolotherapy.Methods From September 2012 to September 2014,34 male patients and 26 female patients with AVMs who underwent embolotherapy(100 sessions in total)with absolute ethanol were included in this study.Invasive systolic blood pressure(SBP)and heart rate(HR)were recorded before and after each injection and throughout the procedure.Differences between the initial and highest SBP(ΔmaxSP)and HR values(ΔmaxHR),as well as the initial and final SBP(ΔSP)and HR(ΔHR)values,were analyzed.We aimed to explore the potential association between these values and the amount of ethanol that was used.Results The total ethanol used was variable(0.01–0.40 mL/kg;mean,0.20 mL/kg).SBP and HR increased after ethanol injection in most sessions(91 in 100 sessions).SBP decreased in 9 sessions(9 in 100 sessions),while HR,oxygen saturation,and end-tidal CO2 decreased in one of the 9 sessions.ΔmaxSP andΔmaxHR averaged 38.4 mmHg and 27.8 bpm,respectively(both P<0.05),whileΔSP andΔHR averaged 3.4 mmHg and 4.0 bpm,respectively(both P<0.05).ΔmaxSP andΔmaxHR were positively correlated with the total dose of ethanol injected.Conclusions Elevations in SBP and HR during ethanol embolotherapy are common,temporary,and most likely pain-mediated;these increases tend to be positively correlated with ethanol dose.Hypotension may be regarded as an acute complication of ethanol embolotherapy.Hypotension combined with bradycardia,oxygen desaturation,and decreased end-tidal CO2 may be a potential predictor of cardiovascular collapse. 展开更多
关键词 Systemic hemodynamic change Ethanol embolotherapy Arteriovenous malformations HYPOTENSION Blood pressure Heart rate
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幽门螺杆菌与胃癌相关的研究进展 被引量:17
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作者 马刚 张汝鹏 梁寒 《中国肿瘤临床》 CAS CSCD 北大核心 2023年第1期44-48,共5页
幽门螺杆菌是一种革兰氏阴性螺旋菌,能够在人胃黏膜定植并持续生存。幽门螺杆菌持续感染被确认是胃癌发生的高危因素之一,与约80%的胃癌病例密切相关。值得注意的是,全球仅1%~2%幽门螺杆菌感染者最终罹患胃癌,这提示幽门螺杆菌致病性、... 幽门螺杆菌是一种革兰氏阴性螺旋菌,能够在人胃黏膜定植并持续生存。幽门螺杆菌持续感染被确认是胃癌发生的高危因素之一,与约80%的胃癌病例密切相关。值得注意的是,全球仅1%~2%幽门螺杆菌感染者最终罹患胃癌,这提示幽门螺杆菌致病性、感染者自身遗传背景和环境因素三者交互作用,促进胃癌发生,但目前尚未完全阐释其中的分子机制。同时,幽门螺杆菌重塑胃免疫微环境,可能降低感染者免疫治疗效果。临床根治幽门螺杆菌感染仍面临一些问题。本文拟对幽门螺杆菌在胃癌发生发展、胃癌免疫中的作用机制和临床治疗的最新研究进展进行综述。 展开更多
关键词 幽门螺杆菌 胃癌 肿瘤发生 肿瘤免疫 根除
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Assimilation of FY-3D MWTS-Ⅱ Radiance with 3D Precipitation Detection and the Impacts on Typhoon Forecasts 被引量:1
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作者 Luyao QIN Yaodeng CHEN +3 位作者 gang ma Fuzhong WENG Deming MENG Peng ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第5期900-919,共20页
Precipitation detection is an essential step in radiance assimilation because the uncertainties in precipitation would affect the radiative transfer calculation and observation errors.The traditional precipitation det... Precipitation detection is an essential step in radiance assimilation because the uncertainties in precipitation would affect the radiative transfer calculation and observation errors.The traditional precipitation detection method for microwave only detects clouds and precipitation horizontally,without considering the three-dimensional distribution of clouds.Extending precipitation detection from 2D to 3D is expected to bring more useful information to the data assimilation without using the all-sky approach.In this study,the 3D precipitation detection method is adopted to assimilate Microwave Temperature Sounder-2(MWTS-Ⅱ)onboard the Fengyun-3D,which can dynamically detect the channels above precipitating clouds by considering the near-real-time cloud parameters.Cycling data assimilation and forecasting experiments for Typhoons Lekima(2019)and Mitag(2019)are carried out.Compared with the control experiment,the quantity of assimilated data with the 3D precipitation detection increases by approximately 23%.The quality of the additional MWTS-Ⅱradiance data is close to the clear-sky data.The case studies show that the average root-mean-square errors(RMSE)of prognostic variables are reduced by 1.7%in the upper troposphere,leading to an average reduction of4.53%in typhoon track forecasts.The detailed diagnoses of Typhoon Lekima(2019)further show that the additional MWTS-Ⅱradiances brought by the 3D precipitation detection facilitate portraying a more reasonable circulation situation,thus providing more precise structures.This paper preliminarily proves that 3D precipitation detection has potential added value for increasing satellite data utilization and improving typhoon forecasts. 展开更多
关键词 numerical weather prediction radiance assimilation microwave temperature sounding FY-3D MWTS-II precipitation detection
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Advances in photodynamic therapy for port-wine stain and our experience
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作者 Lixin Zhang Hanru Ying +1 位作者 gang ma Xiaoxi Lin 《Chinese Journal of Plastic and Reconstructive Surgery》 2023年第2期96-99,共4页
Port-wine stain(PWS)is a congenital capillary malformation that occurs in 0.3%–0.5%of newborns.The pulsed dye laser is the current gold standard treatment for PWS;however,its efficacy is poor.Photosensitizer photodyn... Port-wine stain(PWS)is a congenital capillary malformation that occurs in 0.3%–0.5%of newborns.The pulsed dye laser is the current gold standard treatment for PWS;however,its efficacy is poor.Photosensitizer photodynamic therapy(PDT)is considered a promising treatment for PWS.Here we provide a comprehensive overview of PDT. 展开更多
关键词 Port-wine stain Photodynamic therapy PHOTOSENSITIZER
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超声造影在眼眶球后肿瘤诊断中的应用价值 被引量:1
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作者 何平 马刚 +1 位作者 郝晓卓 李沅武 《国际眼科杂志》 CAS 北大核心 2021年第12期2199-2201,共3页
目的:分析眼眶球后肿瘤的超声造影特点,探讨超声造影在眼眶球后肿瘤诊断中的应用价值。方法:回顾性分析沈阳市第四人民医院2012-03/2015-05诊治的52例52眼眼眶球后肿瘤患者的超声造影资料,以病理结果分为良性肿瘤组41眼,恶性肿瘤组11眼... 目的:分析眼眶球后肿瘤的超声造影特点,探讨超声造影在眼眶球后肿瘤诊断中的应用价值。方法:回顾性分析沈阳市第四人民医院2012-03/2015-05诊治的52例52眼眼眶球后肿瘤患者的超声造影资料,以病理结果分为良性肿瘤组41眼,恶性肿瘤组11眼。应用SonoLiver软件分析造影资料,获得时间-强度(TI)曲线和定量数据。结果:良性肿瘤组TI曲线多呈快进慢出模式,恶性肿瘤组TI曲线多呈快进快出模式。定量数据:恶性肿瘤组上升时间(RT)、平均渡越时间(mTT)低于良性肿瘤组(P<0.05);两组间峰值强度(IMAX)无差异(P>0.05)。结论:超声造影可为眼眶球后肿瘤的鉴别诊断提供影像学依据,有助于术前的定性诊断。 展开更多
关键词 超声造影 眼眶肿瘤 海绵状血管瘤
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Latest Progress of the Chinese Meteorological Satellite Program and Core Data Processing Technologies 被引量:42
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作者 Peng ZHANG Qifeng LU +9 位作者 Xiuqing HU Songyan GU Lei YANG Min MIN Lin CHEN Na XU Ling Sun Wenguang BAI gang ma Di XIAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第9期1027-1045,共19页
In this paper,the latest progress,major achievements and future plans of Chinese meteorological satellites and the core data processing techniques are discussed.First,the latest three FengYun(FY)meteorological satelli... In this paper,the latest progress,major achievements and future plans of Chinese meteorological satellites and the core data processing techniques are discussed.First,the latest three FengYun(FY)meteorological satellites(FY-2H,FY-3D,and FY-4A)and their primary objectives are introduced Second,the core image navigation techniques and accuracies of the FY meteorological satellites are elaborated,including the latest geostationary(FY-2/4)and polar-orbit(FY-3)satellites.Third,the radiometric calibration techniques and accuracies of reflective solar bands,thermal infrared bands,and passive microwave bands for FY meteorological satellites are discussed.It also illustrates the latest progress of real-time calibration with the onboard calibration system and validation with different methods,including the vicarious China radiance calibration site calibration,pseudo invariant calibration site calibration,deep convective clouds calibration,and lunar calibration.Fourth,recent progress of meteorological satellite data assimilation applications and quantitative science produce are summarized at length.The main progress is in meteorological satellite data assimilation by using microwave and hyper-spectral infrared sensors in global and regional numerical weather prediction models.Lastly,the latest progress in radiative transfer,absorption and scattering calculations for satellite remote sensing is summarized,and some important research using a new radiative transfer model are illustrated. 展开更多
关键词 METEOROLOGICAL SATELLITE GEOLOCATION calibration and validation SATELLITE data ASSIMILATION RADIATIVE TRANSFER model
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高度近视并发白内障患者行飞秒激光辅助超声乳化术的视功能变化 被引量:7
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作者 马刚 黄旭东 +3 位作者 姜雅琴 徐鑫彦 盛帅 任建涛 《国际眼科杂志》 CAS 北大核心 2020年第6期1064-1067,共4页
目的:研究高度近视并发白内障患者行飞秒激光辅助超声乳化术的视功能变化。方法:高度近视并发白内障患者97例97眼皆给予实施飞秒激光辅助白内障超声乳化联合人工晶状体植入术,于术前1d,术后1d,1wk,1、3、6、12mo检查最佳矫正视力、调节... 目的:研究高度近视并发白内障患者行飞秒激光辅助超声乳化术的视功能变化。方法:高度近视并发白内障患者97例97眼皆给予实施飞秒激光辅助白内障超声乳化联合人工晶状体植入术,于术前1d,术后1d,1wk,1、3、6、12mo检查最佳矫正视力、调节功能(负/正调节力、调节灵活度)、集合功能(集合近点、融合范围)、调节性集合与调节比率(AC/A值)、远距立体视锐度,进行统计学分析。结果:术后各时间点最佳矫正视力均较术前提高(P<0.05),术后各时间点间均无差异(P>0.05)。调节功能:术前及术后各时间负相对调节、调节灵敏度均无差异(P>0.05);术后1d,1wk,1mo正相对调节与术前均无差异(P>0.05),术后3、6、12mo与术前均有差异(P<0.05)。集合功能:术后1d,1wk集合近点均较术前有差异(P<0.05),术后6mo与术后12mo无差异(P>0.05),余各时间点间均有差异(P<0.05);术后1d,1wk,1mo融合范围与术前均无差异(P>0.05),术后3、6、12mo与术前均有差异(P<0.05)。术后1d,1wk AC/A值较术前均有差异(P<0.05),术后6mo与术后12mo无差异(P>0.05),余各时间点间均有差异(P<0.05)。术后1d,1wk,1mo远距立体视锐度与术前均无差异(P>0.05),术后3、6、12mo与术前均有差异(P<0.05)。结论:高度近视并发白内障患者行飞秒激光辅助超声乳化联合人工晶状体植入术,术后早期最佳矫正视力较术前明显提高,而视功能恢复相对缓慢。 展开更多
关键词 白内障 晶状体 视功能 飞秒激光 高度近视 超声乳化
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Recent progress in the study of Hedgehog signaling 被引量:9
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作者 gang ma Yue Xiao Lin He 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第3期129-137,共9页
The Hedgehog (Hh) family of secreted signaling proteins plays a critical role in regulating the development of several tissues and organ systems. The ability of Hh proteins to exert their biological effects is regul... The Hedgehog (Hh) family of secreted signaling proteins plays a critical role in regulating the development of several tissues and organ systems. The ability of Hh proteins to exert their biological effects is regulated by a series of post-translational processes. These processes include an intramolecular cleavage, covalent addition of cholesterol and/or palmitate, and conversion into a multimeric freely diffusible form. The processing of Hh proteins affects their trafficking, potency, and ability to signal over several cell diameters. Here we review the current understanding of the Hh signaling mechanisms that govern the establishment of the Hh gradient and the transduction of the Hh signal in the light of recent data. 展开更多
关键词 HEDGEHOG PROCESSING signal transduction
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Experimental and numerical investigation of Weibullian behavior of grain crushing strength 被引量:4
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作者 Quanshui Huang Wei Zhou +2 位作者 gang ma Tang-Tat Ng Kun Xu 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第2期401-411,共11页
The Weibullian behavior of single grain crushing strength was investigated experimentally and numerically with the aim of enhancing the understanding of rock grain breakage.The morphologies of pebble grains were obtai... The Weibullian behavior of single grain crushing strength was investigated experimentally and numerically with the aim of enhancing the understanding of rock grain breakage.The morphologies of pebble grains were obtained using white light 3D laser scanning and image processing.A grain shape library was constructed for grain shape analysis with different shape descriptors.The use of the shape library and grain stability analysis is discussed for a suggested procedure to rotate a grain to its most stable configuration.Single grain crushing tests were performed for 30 pebbles to obtain force-displacement curves and fracture patterns.Each grain was compressed diametrically between flat platens.As expected,the values of the stress at bulk fracture follow a Weibull distribution.A procedure for generating crushable agglomerates with realistic particle shapes was demonstrated,which was accomplished in the discrete element modeling(DEM)of the single grain crushing test.The work presented here is novel in that both the heterogeneous micro-structures and randomly distributed flaws are considered.The DEM results demonstrate that the proposed modeling approach and calibrated parameters are reliable and can reflect the crushing behavior of rock pebbles.Finally,three parametric studies were presented evaluating the effects of micro-crack density,micro-crack disorder,and grain morphology on the Weibullian behavior of the crushing strength,none of which has previously been thoroughly considered.These three studies provide a deeper insight into the origin of the Weibullian behavior of single grain crushing strength. 展开更多
关键词 Rock grain Grain crushing test Discrete element modeling 3D scanning technique Grain stability Weibullian behavior
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Ileocecal intussusception caused by two different tumors - which is the culprit lesion? A case report 被引量:2
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作者 Wu-Feng Fan gang ma +4 位作者 Gui-Chen Li Jin Long Yuan-Hong Xu Ke-Jian Guo Zhe Liu 《World Journal of Clinical Cases》 SCIE 2020年第10期2044-2049,共6页
BACKGROUND Ileocecal intussusception caused by two different tumors is rare,according to a literature review.We describe a case of a male patient with a cauliflower-like mass in the middle of the transverse colon obse... BACKGROUND Ileocecal intussusception caused by two different tumors is rare,according to a literature review.We describe a case of a male patient with a cauliflower-like mass in the middle of the transverse colon observed by colonoscopy before surgery.It was considered to be intussusception caused by colon cancer.However,a substantial lipomatous mass was seen in the distal end of the intussusception by computed tomography before surgery,which posed a challenge in the preoperative diagnosis.CASE SUMMARY We report a 72-year-old male patient with intussusception.The patient underwent right hemicolectomy and cholecystectomy in our hospital on April 29,2019.During operation,the ileum was inserted into the ascending colon by about 15 cm,and a tumor with a diameter of approximately 3.0 cm was observed in the distal part of the intestine.An atypical liposarcoma/highly differentiated liposarcoma in the adipose tissue was suspected in the postoperative pathology,and a lipoma was diagnosed after MDM2 gene testing.A 4.0 cm×5.0 cm polypoid mass was seen immediately adjacent to the mass,and the postoperative pathology report suggested a high-level tubular adenoma.The patient was eventually cured and discharged with an uneventful follow-up.CONCLUSION Intussusception caused by two different types of masses is extremely rare.At present,surgery is the best treatment once intussusception is diagnosed. 展开更多
关键词 Adult intussusception Two different tumors Right hemicolectomy and cholecystectomy Atypical liposarcoma High-level tubular adenoma Case report
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Microstructure and mechanical properties of Cu/Al joints brazed using(Cu,Ni,Zr,Er)-modified Al−Si filler alloys 被引量:1
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作者 Hua-xin LI Ying-dian FENG +7 位作者 Wei-jian SHEN Chuan-yang LÜ Wen-jian ZHENG Ying-he ma gang ma Zhong-ping JIN Yan-ming HE Jian-guo YANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第11期3623-3634,共12页
To design a promising Al−Si filler alloy with a relatively low melting-point,good strength and plasticity for the Cu/Al joint,the Cu,Ni,Zr and Er elements were innovatively added to modify the traditional Al−Si eutect... To design a promising Al−Si filler alloy with a relatively low melting-point,good strength and plasticity for the Cu/Al joint,the Cu,Ni,Zr and Er elements were innovatively added to modify the traditional Al−Si eutectic filler.The microstructure and mechanical properties of filler alloys and Cu/Al joints were investigated.The result indicated that the Al−Si−Ni−Cu filler alloys mainly consisted of Al(s,s),Al_(2)(Cu,Ni)and Si(s,s).The Al−10Si−2Ni−6Cu filler alloy exhibited relatively low solidus(521℃)and liquidus(577℃)temperature,good tensile strength(305.8 MPa)and fracture elongation(8.5%).The corresponding Cu/Al joint brazed using Al−10Si−2Ni−6Cu filler was mainly composed of Al_(8)(Mn,Fe)_(2)Si,Al_(2)(Cu,Ni)3,Al(Cu,Ni),Al_(2)(Cu,Ni)and Al(s,s),yielding a shear strength of(90.3±10.7)MPa.The joint strength was further improved to(94.6±2.5)MPa when the joint was brazed using the Al−10Si−2Ni−6Cu−0.2Er−0.2Zr filler alloy.Consequently,the(Cu,Ni,Zr,Er)-modified Al−Si filler alloy was suitable for obtaining high-quality Cu/Al brazed joints. 展开更多
关键词 Cu/Al joint BRAZING Al−Si filler alloy interface structure joint strength
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向变极端相干阵风下浮式风机系泊线断裂风险因素分析 被引量:2
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作者 马刚 何栗兴 +2 位作者 张旭 董晔弘 白勇 《风机技术》 2022年第3期57-62,共6页
系泊系统是保障浮式风机系统稳定安全运行的关键。掌握极端环境下引发浮式风机系泊破断失效风险的原因,对于优化系统设计及风险应急决策具有重要意义。目前极端阵风条件对浮式风机系泊安全造成何种影响仍不清晰。本文对某半潜式浮式风... 系泊系统是保障浮式风机系统稳定安全运行的关键。掌握极端环境下引发浮式风机系泊破断失效风险的原因,对于优化系统设计及风险应急决策具有重要意义。目前极端阵风条件对浮式风机系泊安全造成何种影响仍不清晰。本文对某半潜式浮式风机开展气动-水动-伺服-弹性耦合数值模拟,预报不同向变极端相干阵风(ECD)工况与浪流耦合环境下系统的气动和水动响应,分析了阵风持续时间、风向变化角等关键参数对系泊张力响应的影响。结果表明系泊张力随持续时间的增大而先增大后减小,当持续9s左右时,所研究浮式风机的系泊张力最大,可能造成系泊线的断裂,这是影响系泊安全的关键参数。 展开更多
关键词 浮式风机 向变极端相干阵风 系泊线 动态响应 持续时间
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Biological properties of neonatal mouse olfactory ensheathing cells purified by differential attachment,cytosine arabinoside,and mitogen stimulation
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作者 Nan Zhao Jun Liu +4 位作者 Hong Gao gang ma Jiangxia Pang Zhongtang Feng Tinghua Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第8期629-634,共6页
BACKGROUND: Differential attachment, chemicals, and immunoaffinity absorption are frequently used to purify olfactory ensheathing cells (OECs). Although purity is high (〉 90%), the complex process, high cost, de... BACKGROUND: Differential attachment, chemicals, and immunoaffinity absorption are frequently used to purify olfactory ensheathing cells (OECs). Although purity is high (〉 90%), the complex process, high cost, decreased cell activity, and cell loss limit their application. OBJECTIVE: To purify OECs using differential attachment, cytosine arabinoside (Ara-C), and mitogen stimulation, and to analyze the biological characteristics of OECs. DESIGN, TIME AND SETTING: Molecular biology experiment of cell morphology and immunocytochemistry. The study was performed at the Institute of Neuroscience, Kunming Medical College between January 2005 and January 2007. MATERIALS: N2 was purchased from Gibico, USA; basic fibroblast growth factor (bFGF) from Invitrogen, USA; PCR master mix kit from Fermentas, USA; nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) from Santa Cruz Biotechnology, USA; OEC specific immunological marker NGF receptor (p75NGFR) from ABCAM, UK; immunological markers of oligodendrocyte and Schwann cells, cyclic nucleotide 3' phosphohydrolase (CNPase), from NeoMarkers, USA; inverted fluorescence microscope from Leica, Germany. METHODS: OECs were isolated from olfactory bulbs of mice provided by Institute of Cancer Research (ICR mice) at postnatal 1 2 days, and purified by differential attachment, Ara-C inhibition (5 mg/L), and 10 μg/L mitogen bFGF and 0.5% N2 stimulation. MAIN OUTCOME MEASURES: OEC growth was observed under inverted microscope; cell purity, as well as expression of NGF and BDNF, was determined by means of immunocytochemistry; expression of β-NGF, BDNF, NT-3, platelet-derived growth factor-B (PDGF-B), bFGF, epidermal growth factor (EGF), NGF receptor TrkA, BDNF receptor TrkB, and NT-4 mRNA were detected by RT-PCR. RESULTS: The majority of in vitro cultured OECs was bipolar or tripolar, and purity was estimated to be 〉 92.4%. Immunocytochemistry demonstrated expression of p75NGFR, NGF, BDNF and CNPase. The RT-PCR results suggested that OECs expressed β-NGF, BDNF, NT-3, PDGF-B, bFGF, EGF, TrkA, and TrkB mRNA. CONCLUSION: Results demonstrated that purity of OECs was high, and that OECs expressed CNPase proteins and produced neurotrophic factors. 展开更多
关键词 olfactory ensheathing cells cell culture IMMUNOCYTOCHEMISTRY RT-PCR
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Efficient allocation of coal de-capacity quota among Chinese provinces:a zero-sum gains data envelopment model
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作者 gang ma Xu Li Jianping Zheng 《Chinese Journal of Population,Resources and Environment》 2019年第3期229-240,共12页
An efficient coal de-capacity quota allocation scheme is key for accelerating China's coal supplyside structure reform.This paper allocates the coal de-capacity quota from the perspective of efficiency to seek the... An efficient coal de-capacity quota allocation scheme is key for accelerating China's coal supplyside structure reform.This paper allocates the coal de-capacity quota from the perspective of efficiency to seek the optimal capacity allocation in each Chinese province.First,we estimate the coal capacity of 24 coal-producing provinces based on boundary production function model.According to the actual coal overcapacity in each province,we initially allocate the coal decapacity quota of reducing 0.8 billion tons among them.Then,we optimize the initial allocation plan by using the zero-sum gains data envelopment model(ZSG-DEA)considering backward coal capacity,coal economic output,and coal resource endowment of each province.The results indicate that:First,there is coal overcapacity all over China,and there are obvious differences among the provinces.Second,the optimal allocation results show that the large coal producing provinces,including Shanxi,Inter Mongolia,Shaanxi,etc.,need to undertake most of the coal decapacity tasks,while the old coal producing provinces in northeast and west China should undertake a heavier burden of coal de-capacity.Third,the“one-size fits-all”approach burdens the small coal producing provinces with reducing coal capacity,leading to a general low enthusiasm for coal de-capacity in these regions. 展开更多
关键词 Coal de-capacity ZSG-DEA model Chinese provinces quota allocation
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