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Reduction of photodynamic damage of blood vessels in the protected region by(–)-epigallocatechin gallate
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作者 Tianlong chen Yi Shen +4 位作者 Li Lin Huiyun Lin Xuejiao Song defu chen Buhong Li 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第3期93-104,共12页
Photodynamic therapy(PDT)has been increasingly used in the clinical treatment of neoplastic,inflammatory and infectious skin diseases.However,the generation of reactive oxygen species(ROS)may induce undesired side eff... Photodynamic therapy(PDT)has been increasingly used in the clinical treatment of neoplastic,inflammatory and infectious skin diseases.However,the generation of reactive oxygen species(ROS)may induce undesired side effects in normal tissue surrounding the treatment lesion,which is a big challenge for the clinical application of PDT.To date,(–)-Epigallocatechin gallate(EGCG)has been widely proposed as an antiangiogenic and antitumor agent for the protection of normal tissue from ROS-mediated oxidative damage.This study evaluates the regulation ability of EGCG for photodynamic damage of blood vessels during hematoporphyrin monomethyl ether(Hemoporfin)-mediated PDT.The quenching rate constants of EGCG for the triplet-state Hemoporfin and photosensitized 1O2 generation are determined to be 6.8×10^(8)M^(−1)S^(−1),respectively.The vasoconstriction of blood vessels in the protected region treated with EGCG hydrogel after PDT is lower than that of the control region treated with pure hydrogel,suggesting an efficiently reduced photodamage of Hemoporfin for blood vessels treated with EGCG.This study indicates that EGCG is an efficient quencher for triplet-state Hemoporfin and 1O2,and EGCG could be potentially used to reduce the undesired photodamage of normal tissue in clinical PDT. 展开更多
关键词 (–)-Epigallocatechin gallate(EGCG) photodynamic therapy hemopor¯n singlet oxygen blood vessel vasoconstriction.
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Tissue optical clearing enhances efficacy of vascular targeted photodynamic therapy of mouse dorsal skin
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作者 Ying Liu Qiushi Wang +5 位作者 Yidi Liu Ying Wang Haixia Qiu Dan Zhu Ying Gu defu chen 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第2期67-78,共12页
Vascular-targeted photodynamic therapy(V-PDT)is an effective treatment for port wine stains(PWS).However,repeated treatment is usually needed to achieve optimal treatment outcomes,possibly due to the limited treatment... Vascular-targeted photodynamic therapy(V-PDT)is an effective treatment for port wine stains(PWS).However,repeated treatment is usually needed to achieve optimal treatment outcomes,possibly due to the limited treatment light penetration depth in the PWS lesion.The optical clearing technique can increase light penetration in depth by reducing light scattering.This study aimed to investigate the V-PDT in combination with an optical clearing agent(OCA)for the therapeutic enhancement of V-PDT in the rodent skinfold window chamber model.Vascular responses were closely monitored with laser speckle contrast imaging(LSCI),optical coherence tomography angiography,and stereo microscope before,during,and after the treatment.We further quantitatively demonstrated the effects of V-PDT in combination with OCA on the blood flow and blood vessel size of skin microvasculature.The combination of OCA and V-PDT resulted in significant vascular damage,including vasoconstriction and the reduction of blood flow.Our results indicate the promising potential of OCA for enhancing V-PDT for treating vascular-related diseases,including PWS. 展开更多
关键词 Vascular-targeted photodynamic therapy(V-PDT) optical clearing agent(OCA) treatment efficacy enhancement skin-fold window chamber port wine stains
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Anti-PD1 antibody and not anti-LAG-3 antibody improves the antitumor effect of photodynamic therapy for treating metastatic breast cancer
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作者 Shan Long Yibing Zhao +9 位作者 Yuanyuan Xu Bo Wang Haixia Qiu Hongyou Zhao Jing Zeng defu chen Hui Li Jiakang Shao Xiaosong Li Ying Gu 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第1期87-103,共17页
Photodynamic therapy(PDT)has limited effects in treating metastatic breast cancer.Immune checkpoints can deplete the function of immune cells;however,the expression of immune checkpoints after PDT is unclear.This stud... Photodynamic therapy(PDT)has limited effects in treating metastatic breast cancer.Immune checkpoints can deplete the function of immune cells;however,the expression of immune checkpoints after PDT is unclear.This study investigates whether the limited e±cacy of PDT is due to upregulated immune checkpoints and tries to combine the PDT and immune checkpoint inhibitor to observe the e±cacy.A metastatic breast cancer model was treated by PDT mediated by hematoporphyrin derivatives(HpD-PDT).The anti-tumor effect of HpD-PDT was observed,as well as CD4þT,CD8þT and calreticulin(CRT)by immunohistochemistry and immunofluorescence.Immune checkpoints on T cells were analyzed byflow cytometry after HpD-PDT.When combining PDT with immune checkpoint inhibitors,the antitumor effect and immune effect were assessed.For HpD-PDT at 100 mW/cm2 and 40,60 and 80 J/cm2,primary tumors were suppressed and CD4þT,CD8þT and CRT were elevated;however,distant tumors couldn't be inhibited and survival could not be prolonged.Immune checkpoints on T cells,especially PD1 and LAG-3 after HpD-PDT,were upregulated,which may explain the reason for the limited HpD-PDT effect.After PDT combined with anti-PD1 antibody,but not with anti-LAG-3 antibody,both the primary and distant tumors were signi-cantly inhibited and the survival time was prolonged,additionally,CD4þT,CD8þT,IFN-þCD4þT and TNF-þCD4þT cells were signi-cantly increased compared with HpD-PDT.HpD-PDT could not combat metastatic breast cancer.PD1 and LAG-3 were upregulated after HpD-PDT.Anti-PD1 antibody,but not anti-LAG-3 antibody,could augment the antitumor effect of HpD-PDT for treating metastatic breast cancer. 展开更多
关键词 Photodynamic therapy anti-PD1 antibody anti-LAG-3 antibody anti-tumor im-mune effects metastatic breast cancer
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Two-Layer Attention Feature Pyramid Network for Small Object Detection
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作者 Sheng Xiang Junhao Ma +2 位作者 Qunli Shang Xianbao Wang defu chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期713-731,共19页
Effective small object detection is crucial in various applications including urban intelligent transportation and pedestrian detection.However,small objects are difficult to detect accurately because they contain les... Effective small object detection is crucial in various applications including urban intelligent transportation and pedestrian detection.However,small objects are difficult to detect accurately because they contain less information.Many current methods,particularly those based on Feature Pyramid Network(FPN),address this challenge by leveraging multi-scale feature fusion.However,existing FPN-based methods often suffer from inadequate feature fusion due to varying resolutions across different layers,leading to suboptimal small object detection.To address this problem,we propose the Two-layerAttention Feature Pyramid Network(TA-FPN),featuring two key modules:the Two-layer Attention Module(TAM)and the Small Object Detail Enhancement Module(SODEM).TAM uses the attention module to make the network more focused on the semantic information of the object and fuse it to the lower layer,so that each layer contains similar semantic information,to alleviate the problem of small object information being submerged due to semantic gaps between different layers.At the same time,SODEM is introduced to strengthen the local features of the object,suppress background noise,enhance the information details of the small object,and fuse the enhanced features to other feature layers to ensure that each layer is rich in small object information,to improve small object detection accuracy.Our extensive experiments on challenging datasets such as Microsoft Common Objects inContext(MSCOCO)and Pattern Analysis Statistical Modelling and Computational Learning,Visual Object Classes(PASCAL VOC)demonstrate the validity of the proposedmethod.Experimental results show a significant improvement in small object detection accuracy compared to state-of-theart detectors. 展开更多
关键词 Small object detection two-layer attention module small object detail enhancement module feature pyramid network
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中国遗传学教学40年发展及展望 被引量:23
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作者 陈德富 卢大儒 +1 位作者 张飞雄 张根发 《遗传》 CAS CSCD 北大核心 2018年第10期916-932,共17页
1978年以来,在中国遗传学会的指导和帮助下,中国遗传学教育工作者在遗传学教学体系、教材建设、教学内容、教学研讨、实验教学、新技术应用等方面进行了全面而系统的探索与改革,成效显著,促进了我国遗传学教育教学事业的大发展,为我国... 1978年以来,在中国遗传学会的指导和帮助下,中国遗传学教育工作者在遗传学教学体系、教材建设、教学内容、教学研讨、实验教学、新技术应用等方面进行了全面而系统的探索与改革,成效显著,促进了我国遗传学教育教学事业的大发展,为我国经济和社会发展培养了大批优秀的遗传学人才。本文总结了近40年来中国遗传学教学的改革成就,并对其未来的发展提出了建议,期待中国遗传学教学质量在新时代再上新台阶。 展开更多
关键词 遗传学 教学 发展 展望 中国遗传学会
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Genome-Wide Analysis of HAESA/HAESA-Like Kinase Family in Rice
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作者 chengliang Wang Dong Li +2 位作者 Pei Wang defu chen Xiwen chen 《American Journal of Plant Sciences》 2020年第8期1254-1269,共16页
In leucine-rich repeat (LRR) receptor-like kinase XI subfamily, </span><i><span style="font-family:Verdana;">Arabidopsis</span></i> <span style="font-family:Verdana;&quo... In leucine-rich repeat (LRR) receptor-like kinase XI subfamily, </span><i><span style="font-family:Verdana;">Arabidopsis</span></i> <span style="font-family:Verdana;">HAESA (AtHAE) and two closely related HAESA-LIKE (AtHSL1 and</span><span style="font-family:Verdana;"> AtHSL2) constitute a small branch. Several reports have described the function and the involved signaling pathway that AtHAE and AtHSLs are involved in. However, the family members and functions of HAE and HSL in rice have not been reported. Here, we performed a genome-wide analysis of the HAE/HSL kinase family in rice. A total of 17 OsHSLs were identified in the genome. Of these, only </span><i><span style="font-family:Verdana;">Os</span></i><span style="font-family:Verdana;">11</span><i><span style="font-family:Verdana;">g</span></i><span style="font-family:Verdana;">11890 was annotated as HSL2;all the other members were annotated as HSL1. Phylogenetic analysis revealed that OsHSLs diverged into three groups, with three </span><i><span style="font-family:Verdana;">Arabidopsis</span></i><span style="font-family:Verdana;"> members constituting a subgroup of group I. Domain analysis revealed that all the homologues had 9-19 LRR repeats and a typical kinase domain at the C-terminus, except that four members lost or evolved their kinase domains. Expression analysis revealed that OsHSLs were co-expressed with genes involved in biotic and abiotic stresses. Microarray data revealed that most OsHSLs were highly expressed in the vegetative tissues and only two members were highly expressed in the reproductive tissues. Most OsHSLs changed their expression profiles when subjected to drought, and salt stress treatments. Our results provide an overview of OsHSL gene family in rice, and suggest that OsHSLs possibly function under biotic and abiotic stresses, thus would help for elucidating the function of OsHSLs gene family </span><i><span style="font-family:Verdana;">in vivo</span></i><span style="font-family:Verdana;">. 展开更多
关键词 HAESA and HAESA-Like Gene Family Rice (Oryza sativa L.) Ara-bidopsis thaliana Receptor-Like Kinase
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Immune response induced by hematoporphyrin derivatives mediated photodynamic therapy:Immunogenic cell death and elevated costimulatory molecules 被引量:3
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作者 Shan Long Yibing Zhao +7 位作者 Yuanyuan Xu Hui Li Hongyou Zhao defu chen Jing Zeng Haixia Qiu Xiaosong Li Ying Gu 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2022年第4期49-60,共12页
Photodynamic therapy(PDT)not only destroys tumor cells directly but also induced anti-tumor immune response through damage-associated molecular patterns(DAMPs).It is reported that anti-tumor response was associated wi... Photodynamic therapy(PDT)not only destroys tumor cells directly but also induced anti-tumor immune response through damage-associated molecular patterns(DAMPs).It is reported that anti-tumor response was associated with light dose and photosensitizer used in PDT.In this study,4T1 tumor cells were implanted on both the right and left flanks of mice.Only the right tumor was treated by HpD-PDT,while the left tumor was not irradiated.The anti-tumor immune response induced by HpD-PDT was investigated.The expression of DAMPs and costimulatory molecules induced by HpD-PDT were tested by immuno fluorescence and flow cytometry in vivo.Different light doses of PDT were designed to treat 4T1 cells.The killing effect was assessed by CCK-8 kit and apoptosis kit.The expression of DAMPs on 4T1 cells after HpDPDT were evaluated by flow cytometry,western blot and ATP kit.This study showed that CD4^(+)T,CD8^(+)T and the production of IFN-γwere increased significantly on day 10 in righttumor after PDT treatment compared with control group.HpD-PDT enhanced the expression of calreticulin(CRT)on tumor tissue.Importantly,co-stimulatory molecular OX-40 and 4-1BB were elevated on CD8^(+)T cells.In vitro,immunogenic death of 4T1 cells was induced after PDT.Besides,the expression of DAMPs increased with the increasing of energy density.This study indicates that anti-tumor immune effect was induced by HpD-PDT.The knowledge of the involvement of CRT,ATP and co-stimulatory molecules uncovers important mechanistic insight into the anti-tumor immunogenicity.It was the first time that co-stimulatory molecules were investigated and found to elevate after PDT. 展开更多
关键词 Photodynamic therapy hematoporphyrin derivatives anti-tumor immune effect immunogenic cell death costimulatory molecule
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Comparative study on Photobiomodulation between 630 nm and 810 nm LED in diabetic wound healing both in vitro and in vivo 被引量:2
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作者 Hongyou Zhao Tengda Ji +8 位作者 Tianzhen Sun Haolin Liu Yidi Liu defu chen Ying Wang Yizhou Tan Jing Zeng Haixia Qiu Ying Gu 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2022年第2期58-67,共10页
Photobiomodulation(PBM)promoting wound healing has been demonstrated by many studies.Currently,630 nm and 810 nm light-emitting diodes(LEDs),as light sources,are frequently used in the treatment of diabetic foot ulcer... Photobiomodulation(PBM)promoting wound healing has been demonstrated by many studies.Currently,630 nm and 810 nm light-emitting diodes(LEDs),as light sources,are frequently used in the treatment of diabetic foot ulcers(DFUs)in clinics.However,the dose-effect relationship of LED-mediated PBM is not fully understood.Furthermore,among the 630 nm and 810 nm LEDs,which one gets a better effect on accelerating the wound healing of diabetic ulcers is not clear.The aim of this study is to evaluate and compare the effects of 630 nm and 810 nm LED-mediated PBM in wound healing both in vitro and in vivo.Our results showed that both 630 nm and 810 nm LED irradiation significantly promoted the proliferation of mouse fibroblast cells(L929)at different light irradiances(1,5,and 10 mW/cm^(2)).The cell proliferation rate increased with the extension of irradiation time(100,200,and 500 s),but it decreased when the irradiation time was over 500 s.Both 630 nm and 810nm LED irradiation(5 mW/cm^(2))significantly improved the migration capability of L929 cells.No difference between 630 nm and 810 nm LED-mediated PBM in promoting cell proliferation and migration was detected.In vivo results presented that both 630 nm and 810 nm LED irradiation promoted the wound healing and the expression of the vascular endothelial growth factor(VEGF)and transforming growth factor(TGF)in the wounded skin of type 2 diabetic mice.Overall,these results suggested that LED-mediated PBM promotes wound healing of diabetic mice through promoting fibroblast cell proliferation,migration,and the expression of growth factors in the wounded skin.LEDs(630 nm and 810 nm)have a similar outcome in promoting wound healing of type 2 diabetic mice. 展开更多
关键词 Photobiomodulation(PBM) light-emitting diode(LED) wound healing diabetic ulcers
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SINGLET OXYGEN DETECTION DURING PHOTOSENSITIZATION 被引量:1
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作者 BUHONG LI HUIYUN LIN +2 位作者 defu chen BRIAN C.WILSON YING GU 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2013年第1期29-37,共9页
Singlet oxygen(^(1)O_(2))is a highly reactive oxygen species involved in numerous chemical and photochemical reactions in diferent biological systems and in particular,in photodynamic therapy(PDT).However,the quantifc... Singlet oxygen(^(1)O_(2))is a highly reactive oxygen species involved in numerous chemical and photochemical reactions in diferent biological systems and in particular,in photodynamic therapy(PDT).However,the quantifcation of^(1)O_(2) generation during in vitro and in vivo pho-tosensitization is still technically challenging.To address this problem,indirect and direct methods for^(1)O_(2)detection have been intensively studied.This review presents the available methods currently in use or under development for detecting and quantifying^(1)O_(2) generation during photosensitization.The advantages and limitations of each method will be presented.Moreover,the future trends in developing PDT-^(1)O_(2) dosimetry will be briefly discussed. 展开更多
关键词 Photodynamic therapy PHOTOSENSITIZATION singlet axygen DETECTION PROBE LUMINESCENCE
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GLOBAL WELL-POSEDNESS FOR THE DENSITY-DEPENDENT INCOMPRESSIBLE MAGNETOHYDRODYNAMIC FLOWS IN BOUNDED DOMAINS 被引量:1
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作者 defu chen Xia YE. 《Acta Mathematica Scientia》 SCIE CSCD 2018年第6期1833-1845,共13页
In this paper, we study the three-dimensional incompressible magnetohydrody-namic equations in a smooth bounded domains, in which the viscosity of the fluid and themagnetic diffusivity are concerned with density. The ... In this paper, we study the three-dimensional incompressible magnetohydrody-namic equations in a smooth bounded domains, in which the viscosity of the fluid and themagnetic diffusivity are concerned with density. The existence of global strong solutions isestablished in vacuum cases, provided the assumption that (| |μ(ρ0)||Lp+|| v(P0)||Lq+||b0||L^3 +||ρO||L^∞) (p,q〉3) is small enough, there is not any smallness condition on thevelocity. 展开更多
关键词 incompressible MHD global solution small initial data
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Effects of pulse width and repetition rate of pulsed laser on kinetics and production of singlet oxygen luminescence
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作者 defu chen Ying Wang +3 位作者 Buhong Li Huiyun Lin Xuechun Lin Ying Gu 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2016年第6期26-34,共9页
Pulsed and continuous-wave(CW)lasers have been widely used as the light sources for photodynamic therapy(PDT)treatment.Singlet oxygen(^(1)O_(2))is known to be a major cytotoxic agent in type-II PDT and can be directly... Pulsed and continuous-wave(CW)lasers have been widely used as the light sources for photodynamic therapy(PDT)treatment.Singlet oxygen(^(1)O_(2))is known to be a major cytotoxic agent in type-II PDT and can be directly detected by its near-infrared luminescence at 1270 nm.As compared to CW laser excitation,the effiects of pulse width and repetition rate of pulsed laser on the kinetics and production of^(1)O_(2)luminescence were quantitatively studied during photosensitization of Rose Bengal.Significant di®erence in kinetics of^(1)O_(2)luminescence was found under the excitation with various pulse widths of nanosecond,microsecond and CW irradiation with power of 20mW.The peak intensity and duration of^(1)O_(2)production varied with the pulse widths for pulsed laser excitation,while the^(1)O_(2)was generated continuously and its production reached a steady state with CW excitation.However,no significant di®erence(P>0:05)in integral^(1)O_(2)production was observed.The results suggest that the PDT efficacy using pulsed laser may be identical to the CW laser with the same wavelength and the same average°uence rate below a threshold in solution. 展开更多
关键词 Photodynamic therapy pulsed laser continuous-wave laser singlet oxygen luminescence
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原发性开角型青光眼患者视觉相关生活质量状况及影响因素
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作者 储锡中 胡成钜 +4 位作者 陈德福 尚晓 王晓燕 黄强杰 梁远波 《中华眼视光学与视觉科学杂志》 CAS CSCD 2023年第10期748-756,共9页
目的:探讨原发性开角型青光眼(POAG)患者视觉相关生活质量(VR-Qol)及影响因素,同时比较患者较好眼视野和双眼整合视野(IVF)与VR-Qol的相关性。方法:横断面研究。连续性纳入2021年6月至2022年9月期间在温州青光眼进展研究(WGPS)中随访的P... 目的:探讨原发性开角型青光眼(POAG)患者视觉相关生活质量(VR-Qol)及影响因素,同时比较患者较好眼视野和双眼整合视野(IVF)与VR-Qol的相关性。方法:横断面研究。连续性纳入2021年6月至2022年9月期间在温州青光眼进展研究(WGPS)中随访的POAG患者。采用双目总和法根据患者右眼和左眼的视野结果计算得到IVF。采用国家眼科研究所视觉功能问卷25(NEI VFQ-25)评估POAG患者VR-Qol,根据NEI VFQ-25中是否有任何1个分量表(排除一般健康及眼部疼痛分量表)得分低于50分将患者分为VR-Qol正常组与异常组。分析年龄、性别、学历、是否已婚、单眼或双眼确诊青光眼、视野进展与否、随访频率、患病时间、降眼压药物数量、视力、视网膜神经纤维层(RNFL)厚度与神经节细胞内丛状层(GCIPL)厚度、视野平均缺损(MD)、视野指数(VFI)丢失率以及有无青光眼家族史、高血压病史、糖尿病病史与VR-Qol的关系。采用独立样本t检验、Mann-Whitney U检验卡方检验进行组间比较。采用单因素和多因素Logistic回归分析VR-Qol的影响因素。结果:共纳入POAG患者116例,男70例,女46例,患者年龄为(61.3±14.6)岁。NEI VFQ-25总分为(88.86±9.44)分。27例(23.3%)患者VR-Qol异常,89例(76.7%)患者VR-Qol正常。与VR-Qol异常组相比,VR-Qol正常组使用降眼压药物数量更少(Z=-2.02,P=0.044)、视力更好(Z=-2.28,P=0.023)、RNFL厚度(Z=-2.64,P=0.008)及GCIPL厚度更厚(Z=-2.29,P=0.022)、视野MD较轻(Z=-4.03,P<0.001)、VFI丢失率较慢(Z=-2.92,P=0.004)。年龄、性别、学历、是否已婚、单眼或双眼确诊青光眼、视野进展与否、随访频率、病程、有无青光眼家族史、高血压病史和糖尿病病史在2组间差异均无统计学意义(均P>0.05)。在VR-Qol异常组,一般视力、角色困难、驾驶这3个分量表的得分较低。POAG患者VR-Qol与双眼MD(r=0.36,P<0.001)、较好眼MD(r=0.30,P<0.001)、较差眼MD(r=0.31,P<0.001)呈正相关。POAG患者VR-Qol的独立危险因素是双眼MD(OR=1.16,95%置信区间:1.02~1.32,P=0.029),而非较好眼MD(OR=1.11,95%置信区间:1.00~1.23,P=0.063)。结论:VR-Qol异常的POAG患者多在一般视力、角色困难、驾驶这3个方面出现困难。视野MD是POAG患者异常VR-Qol的独立危险因素,相比较好眼MD,双眼MD更能帮助识别需要干预的患者。 展开更多
关键词 青光眼 生活质量 国家眼科研究所视学功能问卷25 影响因素 视野
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Directed Evolution of Insoluble Arabidopsis thaliana Zeta Class Glutathione S-Transferase Mutants for Higher Solubility in Escherichia coli
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作者 Yicun Wang Feng Zhang +2 位作者 Haiwei chen Xiwen chen defu chen 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2013年第6期319-322,共4页
Expression of recombinant protein in Escherichia coli (E.coli) is generally considered as one of the ideal systems to produce proteins for industrial production.However,the majority of proteins usually fail to fold ... Expression of recombinant protein in Escherichia coli (E.coli) is generally considered as one of the ideal systems to produce proteins for industrial production.However,the majority of proteins usually fail to fold into their native state and accumulate as insoluble inclusion bodies with no biological activity in E.coli(Yang et al.,2003). 展开更多
关键词 Directed Evolution of Insoluble Arabidopsis thaliana Zeta Class Glutathione S-Transferase Mutants for Higher Solubility in Escherichia coli coli
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