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Using choroidal thickness to detect myopic macular degeneration 被引量:2
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作者 Ran Liu Meng Xuan +10 位作者 De-Cai Wang Ou Xiao Xin-Xing Guo Jian Zhang Wei Wang Monica Jong Padmaja Sankaridurg Kyoko Ohno-Matsui Qiu-Xia Yin Ming-Guang He Zhi-Xi Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期317-323,共7页
AIM:To explore the usage of choroidal thickness measured by swept-source optical coherence tomography(SS-OCT)to detect myopic macular degeneration(MMD)in high myopic participants.METHODS:Participants with bilateral hi... AIM:To explore the usage of choroidal thickness measured by swept-source optical coherence tomography(SS-OCT)to detect myopic macular degeneration(MMD)in high myopic participants.METHODS:Participants with bilateral high myopia(≤−6 diopters)were recruited from a subset of the Guangzhou Zhongshan Ophthalmic Center-Brien Holden Vision Institute High Myopia Cohort Study.SS-OCT was performed to determine the choroidal thickness,and myopic maculopathy was graded by the International Meta-Analysis for Pathologic Myopia(META-PM)Classification.Presence of MMD was defined as META-PM category 2 or above.RESULTS:A total of 568 right eyes were included for analysis.Eyes with MMD(n=106,18.7%)were found to have older age,longer axial lengths(AL),higher myopic spherical equivalents(SE),and reduced choroidal thickness in each Early Treatment Diabetic Retinopathy Study(ETDRS)grid sector(P<0.001).The area under the receiver operating characteristic(ROC)curves(AUC)for subfoveal choroidal thickness(0.907)was greater than that of the model,including age,AL,and SE at 0.6249,0.8208,and 0.8205,respectively.The choroidal thickness of the inner and outer nasal sectors was the most accurate indicator of MMD(AUC of 0.928 and 0.923,respectively).An outer nasal sector choroidal thickness of less than 74μm demonstrated the highest odds of predicting MMD(OR=33.8).CONCLUSION:Choroidal thickness detects the presence of MMD with high agreement,particularly of the inner and outer nasal sectors of the posterior pole,which appears to be a biometric parameter more precise than age,AL,or SE. 展开更多
关键词 high myopia choroidal thickness myopic macular degeneration swept-source optical coherence tomography
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Design and application of thickness measurement calibration system based on laser displacement sensor
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作者 SUN Jin YU Zijin 《Baosteel Technical Research》 CAS 2024年第2期39-46,共8页
This study aims to improve the accuracy and safety of steel plate thickness calibration.A differential noncontact thickness measurement calibration system based on laser displacement sensors was designed to address th... This study aims to improve the accuracy and safety of steel plate thickness calibration.A differential noncontact thickness measurement calibration system based on laser displacement sensors was designed to address the problems of low precision of traditional contact thickness gauges and radiation risks of radiation-based thickness gauges.First,the measurement method and measurement structure of the thickness calibration system were introduced.Then,the hardware circuit of the thickness system was established based on the STM32 core chip.Finally,the system software was designed to implement system control to filter algorithms and human-computer interaction.Experiments have proven the excellent performance of the differential noncontact thickness measurement calibration system based on laser displacement sensors,which not only considerably improves measurement accuracy but also effectively reduces safety risks during the measurement process.The system offers guiding significance and application value in the field of steel plate production and processing. 展开更多
关键词 steel plate thickness high precision measurement noncontact thickness measurement laser displace-ment sensor
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Value of optical coherence tomography measurement of macular thickness and optic disc parameters for glaucoma screening in patients with high myopia
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作者 Hua Mu Rui-Shu Li +1 位作者 Zhen Yin Zhuo-Lei Feng 《World Journal of Clinical Cases》 SCIE 2023年第14期3187-3194,共8页
BACKGROUND The basic method of glaucoma diagnosis is visual field examination,however,in patients with high myopia,the diagnosis of glaucoma is difficult.AIM To explore the value of optical coherence tomography(OCT)fo... BACKGROUND The basic method of glaucoma diagnosis is visual field examination,however,in patients with high myopia,the diagnosis of glaucoma is difficult.AIM To explore the value of optical coherence tomography(OCT)for measuring optic disc parameters and macular thickness as a screening tool for glaucoma in patients with high myopia.METHODS Visual values(contrast sensitivity,color vision,and best-corrected visual acuity)in three groups,patients with high myopia in Group A,patients with high myopia and glaucoma in Group B,and patients with high myopia suspicious for glaucoma in Group C,were compared.Optic disc parameters,retinal nerve fiber layer(RNFL)thickness,and ganglion cell layer(GCC)thickness were measured using OCT technology and used to compare the peri-optic disc vascular density of the patients and generate receiver operator characteristic(ROC)test performance curves of the RNFL and GCC for high myopia and glaucoma.RESULTS Of a total of 98 patients admitted to our hospital from May 2018 to March 2022,totaling 196 eyes in the study,30 patients with 60 eyes were included in Group A,33 patients with 66 eyes were included in Group B,and 35 patients with 70 eyes were included in Group C.Data were processed for Groups A and B to analyze the efficacy of RNFL and GCC measures in distinguishing high myopia from high myopia with glaucoma.The area under the ROC curve was greater than 0.7,indicating an acceptable diagnostic value.CONCLUSION The value of OCT measurement of RNFL and GCC thickness in diagnosing glaucoma in patients with high myopia and suspected glaucoma is worthy of development for clinical use. 展开更多
关键词 high myopia suspected glaucoma Optical coherence tomography Retinal nerve fiber layer thickness Ganglion cell layer thickness Diagnostic efficacy
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Analysis of the Risk of Water Breakout in the Bottom Plate of High-Intensity Mining of Extra-Thick Coal Seams
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作者 Shuo Wang Hongdong Kang Xinchen Wang 《Journal of Geoscience and Environment Protection》 2024年第5期81-91,共11页
In order to clarify the danger of water breakout in the bottom plate of extra-thick coal seam mining, 2202 working face of a mine in the west is taken as the research object, and it is proposed to use the on-site moni... In order to clarify the danger of water breakout in the bottom plate of extra-thick coal seam mining, 2202 working face of a mine in the west is taken as the research object, and it is proposed to use the on-site monitoring means combining borehole peeping and microseismic monitoring, combined with the theoretical analysis to analyze the danger of water breakout in the bottom plate. The results show that: 1) the theoretically calculated maximum damage depth of the bottom plate is 27.5 m, and its layer is located above the Austrian ash aquifer, which has the danger of water breakout;2) the drill hole peeping at the bottom plate of the working face shows that the depth of the bottom plate fissure development reaches 26 m, and the integrity of the water barrier layer has been damaged, so there is the risk of water breakout;3) for the microseismic monitoring of the anomalous area, the bottom plate of the return air downstream channel occurs in the field with a one-week lag, which shows that microseismic monitoring events may reflect the water breakout of the underground. This shows that the microseismic monitoring events can reflect the changes of the underground flow field, which can provide a reference basis for the early warning of water breakout. The research results can provide reference for the prediction of sudden water hazard. 展开更多
关键词 Extra-thick Coal Seam high-Intensity Mining Microseismic Monitoring Water-Surge Hazard Borehole Peeping
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Measurement of retinal thickness in macular region of high myopic eyes using spectral domain OCT 被引量:10
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作者 Ai-Ping Song Xin-Yi Wu +3 位作者 Jian-Rong Wang Wei Liu Yan Sun Tao Yu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2014年第1期122-127,共6页
AIM: To investigate the changes of retinal thickness in macula of high myopic eyes using spectral domain optical coherence tomography(OCT). ·METHODS: Middle-aged and young myopic patients were divided into three ... AIM: To investigate the changes of retinal thickness in macula of high myopic eyes using spectral domain optical coherence tomography(OCT). ·METHODS: Middle-aged and young myopic patients were divided into three groups according to their refractive error/axial length: low and medium myopia group(LMMG),high myopia group(HMG) and super high myopia group(SHMG). Cirrus HD-OCT was used to evaluate total average macular thickness,central subfield thickness,inner/outer macular thickness and macular volume. The differences among experimental groups were analyzed by one-factor analysis of variance. Associations between macular thickness and refractive error/axial length were analyzed by Pearson correlation analysis. ·RESULTS: There was no significant difference in age among the three groups(P =0.2789). The mean refraction error in the LMMG,HMG,and SHMG groups was-2.49 ± 1.38D,-8.53 ±1.95D and-13.88 ±1.76D,respectively(P 【 0.001). The central subfield thickness of three groups was 244.56 ±12.19μm,254.33 ±11.61μm and 261.75 ± 11.83μm,respectively,and there were statistically significance between random two groups. The total average macular thickness,inner/outer macular thickness,and macular volume decreased with increased myopia/axial length. Average foveal thickness had negative correlations with refractive error(P 【0.001),and positive correlations with axial length. The inferior and temporal inner macular thickness,all the quadrants of outer ring,total average macular thickness and macular volume featured positive correlations with refractive error,and negative correlations with axial length. Average foveal thickness,superior and temporal innermacular thicknesses,and temporal outer macular thickness was lower in females compared to males. ·CONCLUSION: With an increase in myopia degree/axial length,the average foveal thickness increased and the inner/outer macular thickness decreased. Females featured thicker average foveal thickness,and thinner macular thickness compared to males. 展开更多
关键词 optical coherence tomography retinal thickness high myopic eyes
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Comparison of choroidal thickness in high myopic eyes after FS-LASIK versus implantable collamer lens implantation with swept-source optical coherence tomography 被引量:3
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作者 Jing Zhang Fang-Lin He +1 位作者 Yan Liu Xian-Qun Fan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第5期773-781,共9页
AIM:To investigate the changes in choroidal thickness(CT)in high myopic eyes after femtosecond laser-assisted in situ keratomileusis(FS-LASIK)surgery or central hole implantable collamer lens(ICL V4c)implantation usin... AIM:To investigate the changes in choroidal thickness(CT)in high myopic eyes after femtosecond laser-assisted in situ keratomileusis(FS-LASIK)surgery or central hole implantable collamer lens(ICL V4c)implantation using swept-source optical coherence tomography(SS-OCT).METHODS:We examined the right eyes of 116 patients with high myopia who were candidates for FS-LASIK surgery and ICL implantation.Sixty eyes underwent ICL V4c implantation and 56 eyes were subjected to FS-LASIK surgery.The CT was measured with SS-OCT.All data were recorded preoperatively and 2 h,1 wk,1 and 3 mo postoperatively.Other demographic information was collected,including age,sex,uncorrected visual acuity(UCVA),best corrected visual acuity(BCVA),spherical equivalent(SE),intraocular pressure(IOP)and axial length(AL).RESULTS:The UCVA improved in both groups and showed no significant differences between groups.There also were no significant differences between the two groups in postoperative BCVA and SE(P=0.581 and 0.203,respectively).The foveal CTs,inner nasal and outer nasal CTs were significantly thicker at 2 h postoperatively in both groups(P<0.05)but returned to baseline levels in 1 wk;after 1 mo,no significant differences were found relative to the preoperative values.At 3 mo in each group,nine regions showed variations in the CT as compared with preoperative thickening,but only the foveal and nasal area CTs preoperative differences were statistically significant(P<0.05).In addition,there was no significant difference in 9 regions of CT between the two groups at all follow-up times(P>0.05).CONCLUSION:The CTs after ICL implantation and FSLASIK surgery are significantly thicker than those before operation,especially in the foveal and nasal areas,but there is no significant difference between the two methods. 展开更多
关键词 choroidal thickness high myopia laser in situ keratomileusis implantable collamer lens implantation swept-source optical coherence tomography
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Impact of Thickness of Polymer Electrolyte Membrane on Temperature Distributions in Single Cell of Polymer Electrolyte Fuel Cell Operated at High Temperature 被引量:4
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作者 Akira Nishimura Yusuke Sato +2 位作者 Masato Yoshimura Satoru Kamiya Masafumi Hirota 《Journal of Energy and Power Engineering》 2018年第2期80-92,共13页
This study is to understand the impact of operating condition, especially initial operation temperature (Tini) which is set in high temperature range, on the temperature profile of the interface between PEM (polyme... This study is to understand the impact of operating condition, especially initial operation temperature (Tini) which is set in high temperature range, on the temperature profile of the interface between PEM (polymer electrolyte membrane) and catalyst layer at the cathode (i.e., the reaction surface) in a single PEFC (polymer electrolyte fuel cell). A 1D multi-plate heat transfer model based on the temperature data of separator measured using thermograph in a power generation experiment was developed to evaluate the reaction surface temperature (Treact). This study investigated the effects of Tini, flow rate and relative humidity of supply gas as well as thickness of PEM on the temperature distribution on reaction surface. As a result, the impact of flow rate of supply gas on the temperature distribution is not significant irrespective of relative humidity conditions as well as PEM type. When operated at high temperature, the temperature distribution is relatively flat in the case of thicker PEM (Nafion 115), while Treact rises from the inlet to the outlet large and the temperature distribution is wide in the case of thin PEM (Nafion 211) irrespective of relative humidity condition. Since the water transfer through PEM in the case of Nafion 211 is better than Nafion 115 due to thin PEM, the power generation is promoted along the gas flow with the aid of humidification by water produced from electrochemical reaction. 展开更多
关键词 PEFC heat transfer model temperature distribution high temperature operation thickness of PEM.
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Investigation of Surface-inset Machines with Mixed Grade Magnets Considering Magnet Thickness
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作者 Youyuan Ni Liang Zhang Zhiwei Qiu 《CES Transactions on Electrical Machines and Systems》 CSCD 2022年第3期252-260,共9页
This paper presents a mixed grade magnet model for surface-inset machines considering the magnet thickness. In the polar coordinates, on the basis of the Laplace/quasi-Poisson equations and boundary conditions, the co... This paper presents a mixed grade magnet model for surface-inset machines considering the magnet thickness. In the polar coordinates, on the basis of the Laplace/quasi-Poisson equations and boundary conditions, the constructed matrix equations are solved and the air gap magnetic field in the machine is derived. Taking an 8-pole/12-slot surface-inset motor as an example, through the presented optimization process, the air gap field is optimized considering the magnet thickness, remanence and magnetization angle. In addition, the back-EMF and electromagnetic torque are analytically obtained. The optimized results show that the proposed mixed grade magnet model has larger electromagnetic torque and smaller torque ripple than the conventional one. Finally, the analytical predictions are evaluated by finite element analysis(FEA). 展开更多
关键词 Mixed grade magnet Surface-inset machines Magnet thickness Remanence Torque ripple
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Selection of Thickness of High Density Polyethylene Film for Mulching in Paddy Rice
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作者 Xiangchen Liu Li Qiao +4 位作者 Zhaocheng Lu Daqing Feng Ping Li Xuejun Fan Kun Xu 《American Journal of Plant Sciences》 2013年第7期1359-1365,共7页
In water deficit area, judicious use of water is essential for increasing area under crop production with limited water supply. Film Mulching has been advocated as an effective means for conserving soil moisture in ri... In water deficit area, judicious use of water is essential for increasing area under crop production with limited water supply. Film Mulching has been advocated as an effective means for conserving soil moisture in rice production. The effects of high density polyethylene (HDPE) film on increasing rice production, controlling weeds and residue amount of plastic were studied under five treatments, including 5, 10, 15 and 20 μm thickness as well as bare cultivation (CK). The results indicated that the HDPE film mulching mode had significant effects on weed control, soil temperature, soil moisture, photosynthetic rate, seedling biomass, yield and residues of plastic film. Combined with economic effect, it showed that the HDPE film of 10 μm is the best option for rice production. 展开更多
关键词 PADDY RICE WEED Soil high-DENSITY POLYETHYLENE Film thickness
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Relationship of plasma homocysteine, soluble intercellular adhesion molecule-1, high mobility group box 1 protein with carotid intima-media thickness in elderly patients with type 2 diabetes mellitus
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作者 Zhijie Cai Jun Xue +4 位作者 Xiaohui Ma Peifeng Chen Biao Ge Yuying Zhang Zhihui Dong 《Discussion of Clinical Cases》 2022年第1期9-12,共4页
Objective:To explore the relationship of plasma homocysteine(Hcy),soluble intercellular adhesion molecule-1(sICAM-1)and high mobility group box 1 protein(HMGB1)with carotid intima-media thickness(c-IMT)in elderly pati... Objective:To explore the relationship of plasma homocysteine(Hcy),soluble intercellular adhesion molecule-1(sICAM-1)and high mobility group box 1 protein(HMGB1)with carotid intima-media thickness(c-IMT)in elderly patients with type 2 diabetes mellitus.Methods:A total of 100 elderly patients who were diagnosed as type 2 diabetes mellitus in Baogang Hospital of Inner Mongolia from June 2017 to May 2020 were chosen as research objects.According to c-IMT,they were divided into the normal group(n=35),the mild to moderate group(n=41)and the severe group(n=24).The expression levels of plasma Hcy,sICAM-1 and HMGB1 were compared between groups respectively.Pearson’s correlation coefficient was used to analyze the relationship of plasma Hcy,sICAM-1,HMGB1 with c-IMT.Results:The comparison in plasma Hcy,sICAM-1,HMGB1 and c-IMT among the three groups of patients was of statistical significance(p<.05).The results of correlation analysis showed that the expression levels of plasma Hcy,sICAM-1 and HMGB1 were positively correlated with c-IMT in elderly patients with type 2 diabetes mellitus(r=.627,.598,.614;p<.05).Conclusions:The expression levels of plasma Hcy,sICAM-1 and HMGB1 are abnormally increased in elderly patients with type 2 diabetes mellitus,and related to c-IMT,which can provide a strong evidence for clinical diagnosis and treatment by detecting their levels in clinical practice. 展开更多
关键词 Type 2 diabetes mellitus Carotid intima-media thickness HOMOCYSTEINE Soluble intercellular adhesion molecule-1 high mobility group box 1 protein
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Magnetic levitation performance of high-temperature superconductor over three magnetic hills of permanent magnet guideway with iron shims of different thicknesses
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作者 Yuming Gong Gang Liang +3 位作者 Lifeng Zhao Yong Zhang Yong Zhao Xuyong Chen 《Journal of Modern Transportation》 2014年第3期187-193,共7页
Superconducting magnetic levitation performance, including levitation force and guidance force, is important for the application of high-temperature super- conducting maglev. Both of them are not only affected by diff... Superconducting magnetic levitation performance, including levitation force and guidance force, is important for the application of high-temperature super- conducting maglev. Both of them are not only affected by different arrays of superconductors and magnets, but also by the thickness of the iron shim between permanent magnets. In order to obtain the best levitation performance, the magnetic field distribution, levitation force, and guidance force of a new type of three magnetic hills of permanent magnet guideway with iron shim of different thicknesses (4, 6, and 8 mm) are discussed in this paper. Simulation analysis and experiment results show that the guideway with iron shim of 8 mm thickness possesses the strongest magnetic field and levitation performance when the suspension gap is larger than 10 mm. However, with the decreasing of suspension gap, the guideway with iron shim of 4 mm thickness possesses the best levitation performance. The phenomena can be attributed to the density distribution of flux and magnetization of iron shim. 展开更多
关键词 high-temperature superconductor Three magnetic hills of permanent magnet guideway thickness of iron shim Levitation force Guidance force
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Study on Plants Selection and Disposition in High-grade Residences 被引量:1
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作者 张若冰 包志毅 《Journal of Landscape Research》 2011年第5期49-51,共3页
With rapid development of economy and emergence of more and more high-grade residences,it had highlighted that high-grade residence was the inevitable tendency of economic development and urban construction.Based on t... With rapid development of economy and emergence of more and more high-grade residences,it had highlighted that high-grade residence was the inevitable tendency of economic development and urban construction.Based on the fact that high-grade residences paid more attention to harmony of human and architecture with nature and required higher for landscaping,the paper emphasized that landscape quality of high-grade residences was the key factor deciding quality of the residence.In view of insufficiencies of plant landscaping planning in high-grade residences at home and abroad,by taking high-grade residences in Hangzhou City for example,analysis had been conducted by selecting typical cases.It pointed out that plants disposition in high-grade residences was unreasonable,architectures and landscapes were isolated,and greening ratio was stressed while design was neglected.And then,corresponding solutions had been proposed.In terms of plants selection,it should reasonably utilize native tree species,and properly select new and high-quality plant species.In terms of harmonious unity between plant landscape and architecture,it should lay stress on unity between sensory design and comfort design.In terms of plant design and disposition,it should stick to the theme of "residential environment",so as to rationalize plant design and disposition,and create more comfortable residential environment. 展开更多
关键词 high-grade RESIDENCES PLANTS LANDSCAPE Plant DISPOSITION RESIDENTIAL environment
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Graded Heterojunction Improves Wide-Bandgap Perovskite for Highly Efficient 4-Terminal Perovskite/Silicon Tandem Solar Cells
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作者 Wenming Chai Lindong Li +6 位作者 Weidong Zhu Dazheng Chen Long Zhou He Xi Jincheng Zhang Chunfu Zhang Yue Hao 《Research》 SCIE EI CSCD 2024年第2期181-190,共10页
Wide-bandgap(WBG)perovskite solar cells(PSCs)are essential for highly efficient and stable silicon/perovskite tandem solar cells.In this study,we adopted a synthetic strategy with lead thiocyanate(Pb(SCN)_(2))additive... Wide-bandgap(WBG)perovskite solar cells(PSCs)are essential for highly efficient and stable silicon/perovskite tandem solar cells.In this study,we adopted a synthetic strategy with lead thiocyanate(Pb(SCN)_(2))additive and methylammonium chloride(MACl)posttreatment to enhance the crystallinity and improve the interface of WBG perovskite films with a bandgap of 1.68 eV.The excessive PbI_(2)was formed at grain boundaries and converted into MAPbI_(3-x)Cl_(x)perovskites,which are utilized to form the graded heterojunction(GHJ)and compressive strain.This is beneficial for passivating nonradiative recombination defects,suppressing halide phase segregation,and facilitating carrier extraction.Subsequently,the device with GHJ delivered a champion efficiency of 20.30%and superior stability in ambient air and under 85℃.Finally,we achieved a recorded efficiency of 30.91%for 4-terminal WBG perovskite/TOPCon tandem silicon solar cells.Our findings demonstrate a promising approach for fabricating efficient and stable WBG PSCs through the formation of GHJ. 展开更多
关键词 PEROVSKITE gradeD highly
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360° fusion for realignment of high grade cervical kyphosis by one step surgery: Case report 被引量:5
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作者 Alessandro Landi Nicola Marotta +3 位作者 Cristina Mancarella Demo Eugenio Dugoni Roberto Tarantino Roberto Delfini 《World Journal of Clinical Cases》 SCIE 2014年第7期289-292,共4页
Surgical treatment for cervical kyphotic deformity is still controversial. Circumferential approach has been well described in the literature but long terms outcomes are not well reported. Important to decide the corr... Surgical treatment for cervical kyphotic deformity is still controversial. Circumferential approach has been well described in the literature but long terms outcomes are not well reported. Important to decide the correct treatment option is the preoperative radiological exams to value the type of deformity(flexible or fixed). We report the case of a 67-year-old woman affected by a severe cervical kyphotic deformity who underwent combined anterior/posterior surgical approach, getting a good reduction of the deformity and an optimal stability in a long term follow up. 展开更多
关键词 CERVICAL DEFORMITY high grade KYPHOSIS Circumferential FUSION Surgical technique DEGENERATIVE CERVICAL spine
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Influence of transient intraocular pressure elevation during laser in situ keratomileusis on rabbit retina thickness 被引量:5
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作者 Hai-Xia Zhao Hui Liu +1 位作者 Chun-Mei Niu Wen-Ying Guan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第6期1089-1093,共5页
AIMTo utilize tissue micro measurement to study the effect of transient high intraocular pressure (IOP) induced by different durations of suction during laser in situ keratomileusis (LASIK) on rabbit retina thickness.... AIMTo utilize tissue micro measurement to study the effect of transient high intraocular pressure (IOP) induced by different durations of suction during laser in situ keratomileusis (LASIK) on rabbit retina thickness.METHODSSixty healthy New Zealand white rabbits were randomly divided into a control group, and 3 negative-pressure suction groups (20s group, 45s group, and 3min group) and each group was comprised of 15 rabbits (30 eyes); the latter 3 groups were the transient high IOP models. The retinal tissue around the papilledema was separated. Hematoxylin and eosin (HE) staining was carried out to generate slices for light microscopy. The changes in the retina thickness values of each layer were measured for all animals in each group at different postoperative recovery periods and compared with the values recorded for the animals in the control group. The thickness of the retinal tissue showed a normal distribution. The ANOVA was performed by using SPSS13.0 statistic software.RESULTSIn the comparison between the 20s and 45s negative-pressure suction groups and the control group, no significant differences were observed, except at 14d. Significant difference was observed between the 3min negative-pressure suction group and the control group, and the retina thickness value of each layer reached a peak at 14d after repair.CONCLUSIONConventional negative suction during LASIK may not lead to significant changes in retinal tissue thickness; however, if the suction duration is increased to 3min, it will cause significant changes in retinal tissue thickness. 展开更多
关键词 laser in situ keratomileusis transient high intraocular pressure retina thickness
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Unique case of oligoastrocytoma with recurrence and grade progression:Exhibiting differential expression of high mobility group-A1 and human telomerase reverse transcriptase 被引量:3
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作者 Puneet Gandhi Richa Khare +3 位作者 Kavita Niraj Nitin Garg Sandeep K Sorte Hanni Gulwani 《World Journal of Clinical Cases》 SCIE 2016年第9期296-301,共6页
Mixed gliomas, primarily oligoastrocytomas, account for about 5%-10% of all gliomas. Distinguishing oligoastrocytoma based on histological features alone has limitations in predicting the exact biological behavior, ne... Mixed gliomas, primarily oligoastrocytomas, account for about 5%-10% of all gliomas. Distinguishing oligoastrocytoma based on histological features alone has limitations in predicting the exact biological behavior, necessitating ancillary markers for greater specificity. In this case report, human telomerase reverse transcriptase(hT ERT) and high mobility group-A1(HMGA1); markers of proliferation and stemness, have been quantitatively analyzed in formalin-fixed paraffin-embedded tissue samples of a 34 years old patient with oligoastrocytoma. Customized florescence-based immunohistochemistry protocol with enhanced sensitivity and specificity is used in the study. The patient presented with a history of generalized seizures and his magnetic resonance imaging scans revealed infiltrative ill-defined mass lesion with calcified foci within the left frontal white matter, suggestive of glioma. He was surgically treated at our center for four consecutive clinical events. Histopathologically, the tumor was identified as oligoastrocytoma-grade Ⅱ followed by two recurrence events and final progression to grade Ⅲ. Overall survival of the patient without adjuvant therapy was more than 9 years. Glial fibrillary acidic protein, p53, Ki-67, nuclear atypia index, pre-operative neutrophillymphocyte ratio, are the other parameters assessed. Findings suggest that hT ERT and HMGA1 are linked to tumor recurrence and progression. Established markers can assist in defining precise histopathological grade in conjuction with conventional markers in clinical setup. 展开更多
关键词 Human TELOMERASE reverse transcriptase high mobility group-A1 Oligoastrocytoma RECURRENCE Tumor grade
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Barrett's esophagus with high grade dysplasia is associated with non-esophageal cancer 被引量:2
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作者 Nir Bar Naama Schwartz +3 位作者 Michal Nissim Naomi Fliss-Isacov Shira Zelber-Sagi Revital Kariv 《World Journal of Gastroenterology》 SCIE CAS 2018年第39期4472-4481,共10页
AIM To study factors associated with esophageal and nonesophageal cancer morbidity among Barrett's esophagus(BE) patients. METHODS A cohort study within a single tertiary center included 386 consecutive patients w... AIM To study factors associated with esophageal and nonesophageal cancer morbidity among Barrett's esophagus(BE) patients. METHODS A cohort study within a single tertiary center included 386 consecutive patients with biopsy proven BE, who were recruited between 2004-2014. Endoscopic and histologic data were prospectively recorded. Cancer morbidity was obtained from the national cancer registry. Main outcomes were BE related(defined as esophagus and cardia) and non-BE related cancers(all other cancers). Cancer incidence and all-causemortality were compared between patients with highgrade dysplasia(HGD) and with low-grade or no dysplasia(non-HGD) using Kaplan-Meier curves and cox regression models.RESULTS Of the 386 patients, 12 had HGD, 7 had a BE related cancer. There were 75(19.4%) patients with 86 cases of lifetime cancers, 76 of these cases were non-BE cancers. Seven(1.8%) and 18(4.7%) patients had BE and non-BE incident cancers, respectively. Twelve(3.1%) patients had HGD as worst histologic result. Two(16.7%) and 16(4.4%) incident non-BE cancers occurred in the HGD and non-HGD group, respectively. Ten-year any cancer and non-BE cancer free survival was 63% and 82% in the HGD group compared to 93% and 95% at the non-HGD group, respectively. Log-rank test for patients with more than one endoscopy, assuring longer follow up, showed a significant difference(P < 0.001 and P = 0.017 respectively). All-cause mortality was not significantly associated with BE HGD.CONCLUSION Patients with BE and HGD, may have a higher risk for all-cause cancer morbidity. The implications on cancer prevention recommendations should be further studied. 展开更多
关键词 Barrett’s ESOPHAGUS high grade DYSPLASIA Esophageal CANCER Upper endoscopy CANCER MORBIDITY
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Synthesis of high grade octahedron diamond through epitaxial growth 被引量:1
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作者 Yi Jianhong(易建宏) National Key Laboratory for Powder Metallurgy, Central South University of Technology, Changsha 410083, P.R. China 《中国有色金属学会会刊:英文版》 EI CSCD 1999年第3期477-480,共4页
The work was based on the relationship between the crystal structure and parameters of diamonds in the synthetic process, in which Ni Mn C powder catalyst was used. At first, the diamond crystals nucleated in a cubic ... The work was based on the relationship between the crystal structure and parameters of diamonds in the synthetic process, in which Ni Mn C powder catalyst was used. At first, the diamond crystals nucleated in a cubic octahedron morphology through controlling such synthetic parameters as temperature and pressure in a parameter region where cubic octahedron ctystals can be obtained. Then the diamond nuclei grew epitaxially into crystals with a perfect octahedron morphology through increasing the synthesis temperature and decreasing the synthesis pressure in a parameter region where octahedron crystals can be obtained. 展开更多
关键词 high grade DIAMOND eqitaxial GROWTH
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Geochemical Characteristics of Archean High-Grade Terrain of Kongling Complex and Early Crustal Evolution of Yangtze Craton 被引量:1
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作者 Ling Wenli Gao Shan Cheng Jianping Zhang Benren Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074 Zheng Haifei Department of Geology, Peking University, Beijing 100871 《Journal of Earth Science》 SCIE CAS CSCD 1998年第2期8-16,共9页
This paper reports the systematic studies of geochemistry on the meta sedimentary rocks, felsic gneisses and amphibolites of the Kongling complex from the Archean high grade terrain of the Yangtze craton. It shows t... This paper reports the systematic studies of geochemistry on the meta sedimentary rocks, felsic gneisses and amphibolites of the Kongling complex from the Archean high grade terrain of the Yangtze craton. It shows that the amphibolites originated from a weakly depleted mantle resource. Nb negative anomaly, negative ε (Nd, t ) and the t DM ages which older than their isochron ages of the TTG gneisses imply the possible existence of the crust older than round about 2.7 Ga in the region. Three types of meta sedimentary rocks are identified from the Kongling complex. The first type originated from the juvenile crust with the features of the first cycle sedimentary rocks. Cratonic sedimentary rocks characterize the second type. Mobilization of REE and other elements resulted from partial melting during the migmatization is found in the third type of meta sedimentary rocks. Apart from the early TTG gneisses, some of the mafic rocks are also expected to be the source rocks of the first type of para rocks. The deposition times of the first and second type paragneisses are closed in the Neoarchean of about 2.7 Ga and the early period of Proterozoic respectively, and the period when cratonization of the Yangtze continental block completed is referred to be earlier than the Mesoproterozoic. Nd isotopic tracing on the magma sources of the Jinning granitic rocks in the region reveals that the major part of the Kongling basement is Neoarchean. 展开更多
关键词 Archean high grade terrain Kongling complex geochemical characteristics tectonic setting cratonization.
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Radiotherapy of high-grade gliomas: current standards and new concepts, innovations in imaging and radiotherapy, and new therapeutic approaches 被引量:19
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作者 Frederic Dhermain 《Chinese Journal of Cancer》 SCIE CAS CSCD 2014年第1期16-24,共9页
The current standards in radiotherapy of high-grade gliomas(HGG) are based on anatomic imaging techniques, usually computed tomography(CT) scanning and magnetic resonance imaging(MRI). The guidelines vary depending on... The current standards in radiotherapy of high-grade gliomas(HGG) are based on anatomic imaging techniques, usually computed tomography(CT) scanning and magnetic resonance imaging(MRI). The guidelines vary depending on whether the HGG is a histological grade 3 anaplastic glioma(AG) or a grade 4 glioblastoma multiforme(GBM). For AG, T2-weighted MRI sequences plus the region of contrast enhancement in T1 are considered for the delineation of the gross tumor volume(GTV), and an isotropic expansion of 15 to 20 mm is recommended for the clinical target volume(CTV). For GBM, the Radiation Therapy Oncology Group favors a two-step technique, with an initial phase(CTV1) including any T2 hyperintensity area(edema) plus a 20 mm margin treated with up to 46 Gy in 23 fractions, followed by a reduction in CTV2 to the contrast enhancement region in T1 with an additional 25 mm margin. The European Organisation of Research and Treatment of Cancer recommends a single-phase technique with a unique GTV, which comprises the T1 contrast enhancement region plus a margin of 20 to 30 mm. A total dose of 60 Gy in 30 fractions is usually delivered for GBM, and a dose of 59.4 Gy in 33 fractions is typically given for AG. As more than 85% of HGGs recur in field, dose-escalation studies have shown that 70 to 75 Gy can be delivered in 6 weeks with relevant toxicities developing in < 10% of the patients. However, the only randomized dose-escalation trial, in which the boost dose was guided by conventional MRI, did not show any survival advantage of this treatment over the reference arm. HGGs are amongst the most infiltrative and heterogeneous tumors, and it was hypothesized that the most highly aggressive areas were missed; thus, better visualization of these high-risk regions for radiation boost could decrease the recurrence rate. Innovations in imaging and linear accelerators(LINAC) could help deliver the right doses of radiation to the right subvolumes according to the dose-painting concept. Advanced imaging techniques provide functional information on cellular density(diffusion MRI), angiogenesis(perfusion MRI), metabolic activity and cellular proliferation [positron emission tomography(PET) and magnetic resonance spectroscopy(MRS)]. All of these non-invasive techniques demonstrated good association between the images and histology, with up to 40% of HGGs functionally presenting a high activity within the non- contrast-enhanced areas in T1. New LINAC technologies, such as intensity-modulated and stereotactic radiotherapy, help to deliver a simultaneous integrated boost(SIB) > 60 Gy. Trials delivering a SIB into a biological GTV showed the feasibility of this treatment, but the final results, in terms of clinical benefits for HGG patients, are still pending. Many issues have been identified: the variety of MRI and PET machines(and amino-acid tracers), the heterogeneity of the protocols used for image acquisition and post-treatment, the geometric distortion and the unreliable algorithms for co-registration of brain anatomy with functional maps, and the semi-quiescent but highly invasive HGG cells. These issues could be solved by the homogenization of the protocols and software applications, the simultaneous acquisition of anatomic and functional images(PET-MRI machines), the combination of complementary imaging tools(perfusion and diffusion MRI), and the concomitant addition of some ad hoc targeted drugs against angiogenesis and invasiveness to chemoradiotherapy. The integration of these hybrid data will construct new synthetic metrics for fully individualized treatments. 展开更多
关键词 成像技术 放射治疗 胶质瘤 标准 创新 放疗 计算机断层扫描 电子直线加速器
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