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Predictive factors for photic phenomena after refractive,rotationally asymmetric,multifocal intraocular lens implantation 被引量:16
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作者 Hungwon Tchah Kiyeun Nam Aeri Yoo 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第2期241-245,共5页
AIM: To investigate the independent factors associated with photic phenomena in patients implanted with refractive,rotationally asymmetric,multifocal intraocular lenses(MIOLs).METHODS: Thirty-four eyes of 34 patie... AIM: To investigate the independent factors associated with photic phenomena in patients implanted with refractive,rotationally asymmetric,multifocal intraocular lenses(MIOLs).METHODS: Thirty-four eyes of 34 patients who underwent unilateral cataract surgery,followed by implantation of rotationally asymmetric MIOLs were included.Distance and near visual acuity outcomes,intraocular aberrations,preferred reading distances,preoperative and postoperative refractive errors,mesopic and photopic pupil diameters,and the mesopic and photopic kappa angles were assessed.Patients were also administered a satisfaction survey.Photic phenomena were graded by questionnaire.Independent-related factors were identified by correlation and bivariate logistic regression analyses.RESULTS: The distance from the photopic to the mesopic pupil center(pupil center shift) was significantly associated with glare/halo symptoms [odds ratio(OR)=2.065,95% confidence interval(CI)=0.916-4.679,P=0.006] and night vision problems(OR=1.832,95% CI=0.721-2.158,P=0.007).The preoperative photopic angle kappa was significantly associated with glare/halo symptoms(OR=2.155,95% CI=1.065-4.362,P=0.041).The photopic angle kappa was also significantly associated with glare/halo symptoms(OR=2.155,95% CI=1.065-4.362,P=0.041) and with night vision problems(OR=1.832,95% CI=0.721-2.158,P=0.007) in patients implanted with rotationally asymmetric MIOLs.CONCLUSION: A large pupil center shift and misalignment between the visual and pupillary axis(angle kappa)may play a role in the occurrence of photic phenomena after implantation of rotationally asymmetric MIOLs. 展开更多
关键词 rotationally asymmetric multifocal intraocular lens pupil center photic phenomena dysphotopsia kappa angle pupil center shift
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A Preliminary Study of the Noninvasive Remote Control System for Rat Bio-Robot 被引量:6
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作者 Xitian Pi~(1,2),Shuangshuang Li~1,Lin Xu~1,Hongying Liu~1,Shenshan Zhou~1,Kang Wei~1,Zhenyu Wang~1,Ziru Jia,Xiaolin Zheng~(1,2),Zhiyu Wen~2 1.Bioengineering College,Chongqing University,Chongqing 400030,P.R.China 2.Key Laboratories for National Defense Science and Technology of Innovative Micro-Nano Devices and System Technology,Chongqing University,Chongqing 400030,P.R.China 《Journal of Bionic Engineering》 SCIE EI CSCD 2010年第4期375-381,共7页
A system is described here that can noninvasively control the navigation of freely behaving rat via ultrasonic,epidermaland LED photic stimulators on the back.The system receives commands from a remote host computer t... A system is described here that can noninvasively control the navigation of freely behaving rat via ultrasonic,epidermaland LED photic stimulators on the back.The system receives commands from a remote host computer to deliver specifiedelectrical stimulations to the hearing,pain and visual senses of the rat respectively.The results demonstrate that the three stimuliwork in groups for the rat navigation.We can control the rat to proceed and make right and left turns with great efficiency.Thisexperiment verified that the rat was able to reach a setting destination in the way of cable with the help of a person through theappropriate coordination of the three stimulators.The telemetry video camera mounted on the head of the rat also achieveddistant image acquisition and helped to adjust its navigation path over a distance of 300 m.In a word,the non-invasive motioncontrol navigation system is a good,stable and reliable bio-robot. 展开更多
关键词 rat navigation BIO-ROBOT ultrasonic stimulator epidermal stimulator LED photic stimulator
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频域光学相干断层扫描黄斑光损伤表现的特点 被引量:7
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作者 王明扬 李筱荣 王光璐 《中华眼外伤职业眼病杂志》 2014年第5期340-343,共4页
目的 探讨频域光学相干断层扫描(fourier-domain optical coherence tomography,FD-OCT)应用于光损伤黄斑病变所表现出的特点及重要性.方法 回顾性研究.对光损伤黄斑病变7例(11只眼)进行FD-OCT检查.包括阳光导致视网膜病变2只眼,电... 目的 探讨频域光学相干断层扫描(fourier-domain optical coherence tomography,FD-OCT)应用于光损伤黄斑病变所表现出的特点及重要性.方法 回顾性研究.对光损伤黄斑病变7例(11只眼)进行FD-OCT检查.包括阳光导致视网膜病变2只眼,电弧光导致视网膜病变6只眼,激光损伤导致视网膜病变3只眼.所有患者均行散瞳眼底检查照相,部分患者行多焦视网膜电图检查.结果 所有患眼均有黄斑区病理改变.视力0.04 ~1.0.FD-OCT显示在视锥细胞内外节层局限性缺失7只眼,视网膜层间低反射暗腔3只眼,黄斑孔1只眼.揭示了光损伤黄斑病变缺损区域不仅存在于视细胞层,还存在于视细胞外节与色素上皮绒毛的连接处.激光损伤的黄斑病变可以表现为多种形态.结论 FD-OCT能够在不同类型光损伤黄斑病变患眼中显示出显著的形态学改变,FD-OCT更能发现视细胞外节与色素上皮绒毛连接处的特征性改变,提高了诊治效率. 展开更多
关键词 黄斑病变 光损伤 断层扫描 光学相干 频域
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Visual distraction alone for the improvement of colonoscopy-related pain and satisfaction 被引量:3
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作者 Shotaro Umezawa Takuma Higurashi +5 位作者 Shiori Uchiyama Eiji Sakai Hidenori Ohkubo Hiroki Endo Takashi Nonaka Atsushi Nakajima 《World Journal of Gastroenterology》 SCIE CAS 2015年第15期4707-4714,共8页
AIM: To evaluate the effect of a relaxing visual distraction alone on patient pain, anxiety, and satisfaction during colonoscopy.METHODS: This study was designed as an endoscopistblinded randomized controlled trial wi... AIM: To evaluate the effect of a relaxing visual distraction alone on patient pain, anxiety, and satisfaction during colonoscopy.METHODS: This study was designed as an endoscopistblinded randomized controlled trial with 60 consecutively enrolled patients who underwent elective colonoscopy at Yokohama City University Hospital, Japan. Patients were randomly assigned to two groups: group 1 watched a silent movie using a head-mounted display, while group 2 only wore the display. All of the colonoscopies were performed without sedation. We examined pain, anxiety, and the satisfaction of patients before and after the procedure using questionnaires that included the Visual Analog Scale. Patients were also asked whether they would be willing to use the same method for a repeat procedure.RESULTS: A total of 60 patients were allocated to two groups. Two patients assigned to group 1 and one patient assigned to group 2 were excluded after the randomization. Twenty-eight patients in group 1 and 29 patients in group 2 were entered into the final analysis. The groups were similar in terms of gender, age, history of prior colonoscopy, and pre-procedural anxiety score. The two groups were comparable in terms of the cecal insertion rate, the time to reach the cecum, the time needed for the total procedure, and vital signs. The median anxiety score during the colonoscopy didnot differ significantly between the two groups(median scores, 20 vs 24). The median pain score during the procedure was lower in group 1, but the difference was not significant(median scores, 24.5 vs 42). The patients in group 1 reported significantly higher median post-procedural satisfaction levels, compared with the patients in group 2(median scores, 89 vs 72, P = 0.04). Nearly three-quarters of the patients in group 1 wished to use the same method for repeat procedures, and the difference in rates between the two groups was statistically significant(75.0% vs 48.3%, P = 0.04). Patients with greater levels of anxiety before the procedure tended to feel a pain 展开更多
关键词 COLONOSCOPY photic stimulation Patientsatisfaction COLORECTAL cancer screening ANESTHESIA
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招飞体检中闪光刺激诱发脑电图1628例分析 被引量:1
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作者 聂林川 郝英 +1 位作者 毛炳应 冯志存 《中华航空航天医学杂志》 CSCD 2003年第4期246-247,共2页
关键词 体格检查 Physical EXAMINATION 闪光诱发试验 photic stimulative ACTIVATION 节律同化 photic driving 脑电描记术 ELECTROENCEPHALOGRAPHY
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Abnormal cortical functional connections in Alzheimer’s disease: analysis of inter-and intra-hemispheric EEG coherence 被引量:4
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作者 蒋正言 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第4期259-264,共6页
To investigate inter- and intra-hemispheric electroencephalography (EEG) coherence at rest and during photic stimulation of patients with Alzheimer's disease (AD). Thirty-five patients (12 males, 23 females; 52~6... To investigate inter- and intra-hemispheric electroencephalography (EEG) coherence at rest and during photic stimulation of patients with Alzheimer's disease (AD). Thirty-five patients (12 males, 23 females; 52~64 y) and 33 sex- and age-matched controls (12 males, 21 females; 56~65 y) were recruited in the present study. EEG signals from C3-C4, P3-P4, T5-T6and O1-O2 electrode pairs resulted from the inter-hemispheric action, and EEG signals from C3-P3, C4-P4, P3-O1, P4-O2, C3-O1,C4-O2, T5-O 1 and T6-O2 electrode pairs resulted from the intra-hemispheric action. The influence of inter- and intra-hemispheric coherence on EEG activity with eyes closed was examined, using fast Fourier transformation from the 16 sampled channels. The frequencies of photic stimulation were fixed at 5, 10 and 15 Hz, respectively. The general decrease of AD patients in inter- and intra-hemispheric EEG coherence was more significant than that of the normal controls at the resting EEG, with most striking decrease observed in the alpha-1 (8.0-9.0 Hz) and alpha-2 (9.5-12.5 Hz) bands. During photic stimulation, inter- and intra-hemispheric EEG coherences of the AD patients having lower values in the alpha (9.5-10.5 Hz) band than those of the control group. It suggests that under stimulated and non-stimulated conditions, AD patients had impaired inter- and intra-hemispheric functional connections, indicating failure of brain activation in alpha-related frequency. 展开更多
关键词 Alzheimer’s disease (AD) Electroencephalography (EEG) Coherence photic stimulation Cortical connectivity
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A Novel Polymethyl Methacrylate (PMMA)-TiO_2 Nanocomposite and Its Thermal and Photic Stability
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作者 ZAN Ling LIU Zhongshi FA Wenjun PENG TianYou 《Wuhan University Journal of Natural Sciences》 CAS 2006年第2期415-418,共4页
A new kind of polymethyl methacrylate (PMMA)-TiO2 nanocomposite was synthesized through polymerization. The thermal and photic stability of this PMMA TiO2 nanocomposites were investigated. The as prepared samples we... A new kind of polymethyl methacrylate (PMMA)-TiO2 nanocomposite was synthesized through polymerization. The thermal and photic stability of this PMMA TiO2 nanocomposites were investigated. The as prepared samples were characterized by scanning electron microscopy (SEM), UV-Vis spectroscopy, differential thermal analysis (DTA) and the photo-induced weight loss, The results show that the photostability of the PMMA-TiO2 nanocomposite is higher than that of the pure PMMA under UV-light irradiation, The weight loss of the pure PMMA reaches 30 % after 300 h UVirradiation, while the composite only 0.3% under the identical experimental condition. The glass transition temperature (TR) of pure PMMA is only 80℃, while the Tg of the composite reaches 258℃. Compared with pure PMMA, the thermal stability of the composite is greatly enhanced. 展开更多
关键词 polymethyl methacrylate PMMA )-TiO2 nanoeomposite POLYMERIZATION thermal and photic stability
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Potential of video games for the promotion of neuroadaptation to multifocal intraocular lenses: a narrative review 被引量:3
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作者 Maria Begona Coco-Martin Pedro LValenzuela +3 位作者 Miguel JMaldonado-López Alejandro Santos-Lozano Ainhoa Molina-Martin David P Pinero 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第11期1782-1787,共6页
Multifocal intraocular lenses(IOLs) are currently usually implanted for the treatment of cataracts because they have been proved to be superior to monofocal IOLs with respect to spectacle independence. In turn, they a... Multifocal intraocular lenses(IOLs) are currently usually implanted for the treatment of cataracts because they have been proved to be superior to monofocal IOLs with respect to spectacle independence. In turn, they are associated with a higher prevalence of dysphotopsia symptoms that is one of the most common causes of patient dissatisfaction. Neuroadaptation seems to play a major role in the optimal adaptation to multifocal IOLs. In this context, the development of strategies that facilitate the neuroadaptation process to multifocality might be an effective strategy to reduce patients' dissatisfaction. Video games have been proved to be effective for the improvement of visual acuity and for the promotion of neuroplasticity in elderly subjects and other populations with cortical-related visual impairment. This narrative review highlights the physiological potential of video games as a perceptual strategy to improve visual acuity and promote neuroplasticity in patients using multifocalIOLs, although research is still needed to confirm these benefits in this specific population, with only one comparative study to this date providing evidence of them. 展开更多
关键词 multifocal intraocular lens dysphotopsia photic phenomena HALOS video games NEUROADAPTATION NEUROPLASTICITY
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频域OCT在激光笔致黄斑病变诊断中的应用 被引量:2
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作者 毕晓达 樊旭 +2 位作者 关娟 赵娜 周历 《中华眼外伤职业眼病杂志》 2016年第5期344-347,共4页
目的探讨频域光学相干断层扫描(FD-OCT)在激光笔致黄斑病变诊断及随访中的应用。方法2013年4月至2015年4月我院眼科门诊就诊的激光笔致黄斑区损伤8例(8眼)。所有患者均进行眼科常规检查及FD—OCT检查。结果伤眼视力下降至0.4—0.8... 目的探讨频域光学相干断层扫描(FD-OCT)在激光笔致黄斑病变诊断及随访中的应用。方法2013年4月至2015年4月我院眼科门诊就诊的激光笔致黄斑区损伤8例(8眼)。所有患者均进行眼科常规检查及FD—OCT检查。结果伤眼视力下降至0.4—0.8。FD—OCT扫描特征主要是视网膜内层损伤、神经上皮层脱离、及视锥细胞内节和外节(IS/OS)层局限性缺失。在治疗1个月后复诊,6例(75.00%)视网膜解剖结构及功能均得到改善(失访1例,电话随访1例),其中2例(2眼、25.00%)视力恢复至1.0。结论FD—OCT检查可以直观地观察视网膜各层微细结构改变,能更清楚地了解激光笔致黄斑区光损伤的动态变化。 展开更多
关键词 黄斑病变 光损伤 激光笔 光学相干断层扫描 频域
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Clinical outcomes with a new design in multifocal intraocular lens:a pilot study
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作者 Jorge L.Alió Pilar Yébana +4 位作者 Mario Cantó Ana B.Plaza Alfredo Vega Jorge L.Aliódel Barrio Francisco Lugo 《Eye and Vision》 SCIE CSCD 2020年第1期366-374,共9页
Purpose:To evaluate the clinical and visual outcomes,quality of near vision and the influence of photic phenomena in patients bilaterally implanted with a new Precizon Presbyopic multifocal intraocular lens(IOL).Metho... Purpose:To evaluate the clinical and visual outcomes,quality of near vision and the influence of photic phenomena in patients bilaterally implanted with a new Precizon Presbyopic multifocal intraocular lens(IOL).Methods:In this prospective consecutive case series,20 eyes of 10 patients were included(mean age 63.80±12.55 years).Uncorrected and corrected visual acuity(far,intermediate and near),subjective refraction,binocular defocus curve,contrast sensitivity(CSV-1000)and quality of vision and satisfaction questionnaires were measured.The follow-up was 12 months after surgery.Results:At 12 months after surgery,uncorrected distance visual acuity(UDVA)improved with surgery(p=0.001)with a value of 0.08±0.08 logMAR.Uncorrected near visual acuity(UNVA)was 0.22±0.12 logMAR and distance corrected near visual acuity(DCNVA)was 0.16±0.13 logMAR.Intermediate distance visual acuity(UIVA)was 0.22±0.10 logMAR.Contrast sensitivity outcomes were similar to normal population in photopic conditions and slightly reduced in mesopic conditions of lighting.Defocus curve showed that this multifocal IOL was able to provide a visual acuity(VA)equal or better to 0.16 logMAR between defocus levels of+1.00 to−2.50 D.Good patient satisfaction was obtained in quality of vision and satisfaction questionnaires outcomes.Conclusions:The Precizon Presbyopic NVA IOL(OPHTEC BV)provides good visual outcomes.This multifocal IOL provides a high percentage of spectacle independence due to good VA at far,intermediate and near distances and satisfactory contrast sensitivity.High patient satisfaction was observed in quality of vision and satisfaction questionnaires with a low percentage of patients manifesting photic phenomena. 展开更多
关键词 Multifocal intraocular lens Near vision photic phenomena Continuous transitional focus optic
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Multimodal imaging in photic retinopathy
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作者 Seyed Ali Tabatabaei Mohammad Soleimani +3 位作者 Bahram Bohrani Ali Banafsheafshan Shahin Faghihi Houshang Faghihi 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第3期523-525,共3页
Dear Editor,We would like to present the importance of multimodal imaginginphoticretinopathyinacaseofphotic retinopathy.A young man presented with a one-day history of left central scotoma and metamorphopsia after exp... Dear Editor,We would like to present the importance of multimodal imaginginphoticretinopathyinacaseofphotic retinopathy.A young man presented with a one-day history of left central scotoma and metamorphopsia after exposure toahandheldlaserpointerbeamduringanightparty.The laser pointer was a class IIIB green laser with a wavelength of532±10nmandmaximalpower<1000mW.However. 展开更多
关键词 MULTIMODAL IMAGING in photic RETINOPATHY FIGURE
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Clinical outcomes with a newvdesign in multifocal intraocular lens:a pilot study
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作者 Jorge L.Alio Pilar Yébana +4 位作者 Mario Canto Ana B.Plaza Alfredo Vega Jorge L.Alio del Barrio Francisco Lugo 《Eye and Vision》 SCIE CSCD 2022年第5期13-21,共9页
Purpose:To evaluate the clinical and visual outcomes,quality of near vision and the influence of photic phenomena in patients bilaterally implanted with a new Precizon Presbyopic multifocal intraocular lens(IOL).Metho... Purpose:To evaluate the clinical and visual outcomes,quality of near vision and the influence of photic phenomena in patients bilaterally implanted with a new Precizon Presbyopic multifocal intraocular lens(IOL).Methods:In this prospective consecutive case series,20 eyes of 10 patients were included(mean age 63.80±12.55 years).Uncorrected and corrected visual acuity(far,intermediate and near),subjective refraction,binocular defocus curve,contrast sensitivity(CSV-1000)and quality of vision and satisfaction questionnaires were measured.The follow-up was 12 months after surgery.Results:At 12 months after surgery,uncorrected distance visual acuity(UDVA)improved with surgery(P=0.001)with a value of 0.08±0.08 logMAR.Uncorrected near visual acuity(UNVA)was 0.22±0.12 logMAR and distance corrected near visual acuity(DCNVA)was 0.16±0.13 logMAR.Intermediate distance visual acuity(UIVA)was 0.22±0.10 logMAR.Contrast sensitivity outcomes were similar to normal population in photopic conditions and slightly reduced in mesopic conditions of lighting.Defocus curve showed that this multifocal iOL was able to provide a visual acuity(VA)equal to or better than 0.16 logMAR between defocus levels of+1.00 to-2.50 D.Good patient satisfaction was obtained in quality of vision and satisfaction questionnaires outcomes.Conclusions:The Precizon Presbyopic NVA IOL(OPHTEC BV)provides good visual outcomes.This multifocal IOL provides a high percentage of spectacle independence due to good VA at far,intermediate and near distances and satisfactory contrast sensitivity.High patient satisfaction was observed in quality of vision and satisfaction questionnaires with a low percentage of patients manifesting photic phenomena. 展开更多
关键词 Multifocal intraocular lens Near vision photic phenomena Continuous transitional focus
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礼貌的关联论初探 被引量:59
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作者 冉永平 《现代外语》 CSSCI 北大核心 2002年第4期387-395,共9页
礼貌是一个语用学及社会语言学共同探讨的传统课题,这方面的研究成果可谓汗牛充栋,其中大多数探讨与社会文化因素密不可分,很少或者缺乏等它和认知因素结合起来进行深入系统的探究,它究竟是一个社交问题还是认知问题?还是社交-认知交互... 礼貌是一个语用学及社会语言学共同探讨的传统课题,这方面的研究成果可谓汗牛充栋,其中大多数探讨与社会文化因素密不可分,很少或者缺乏等它和认知因素结合起来进行深入系统的探究,它究竟是一个社交问题还是认知问题?还是社交-认知交互作用的现象?还缺乏定论。从这些问题出发,本文首先回顾了Lakoff的礼貌观和礼貌规则,并提出不同礼貌规则之间是否存在优选问题;然后讨论了有关礼貌的多种论述,以旨重新审视什么是礼貌以及传统礼貌观可能面临的挑战;接着借助关联理论对礼貌展开了部分讨论,以旨说明礼貌是一种关联性期待,是理解的结果;最后以日常言语交际中寒暄语之类的应酬语为例,以旨指出寒暄语的目的就是通过建立、维护交际双方的认知环境,从而实现一定的社交目的。是否可以以及如何将礼貌的社交文化语用分析和认知分析结合起来,是本研究的一个基本出发点,认知效果和礼貌取得的社交语用效果之间是否存在排列顺序或优先问题?它们是否在本质上存在一致性?如何将这两种效果统一起来,建立一个既可以反映具有普遍意义的社交文化特征,又能够说明人类认知特点的、综合性的理论模式?这是本文最后提出的问题,以期与读者共同探讨,将礼貌的有关研究再推向深入。 展开更多
关键词 礼貌 关联论 认知环境 寒暄语 社交语用 文化语用 应酬语 社会语言学 关联理论 语用学
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人脑视皮质功能MRI的初步研究及临床应用 被引量:40
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作者 张淑倩 刘连祥 +4 位作者 吴杰 吴晶 赵华东 钱佐林 吴育锦 《中华放射学杂志》 CAS CSCD 北大核心 2001年第7期524-527,共4页
目的 本实验应用功能磁共振成像 (fMRI)的回波平面 (EPI)技术 ,着重研究了人脑视皮质的血氧水平依赖 (BOLD)的功能磁共振成像。方法 本实验包括对 36名正常健康志愿者及 17例具有枕区病变患者的fMRI研究。在刺激和静止 2种对比条件下... 目的 本实验应用功能磁共振成像 (fMRI)的回波平面 (EPI)技术 ,着重研究了人脑视皮质的血氧水平依赖 (BOLD)的功能磁共振成像。方法 本实验包括对 36名正常健康志愿者及 17例具有枕区病变患者的fMRI研究。在刺激和静止 2种对比条件下采集枕区的回波平面图像。结果 主要视皮质位于双侧距状裂两侧 ,属于布劳德曼 (Brodmann) 17区。 3例具有距状裂附近病变的患者的视皮质由于病变的占位效应而发生移位。结论 fMRI可用于在活体人脑上研究各功能区活动。视觉刺激下的fMRI可对人脑视皮质初步定位。由于病变占位效应的影响 ,病变周围的功能活动区常发生变形或移位。 展开更多
关键词 磁共振成像 视皮质 光刺激 回波平面成像 临床应用
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蓝光诱导体外培养的人视网膜色素上皮细胞凋亡 被引量:28
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作者 蔡善君 严密 张军军 《中华眼底病杂志》 CAS CSCD 北大核心 2005年第6期384-387,共4页
目的观察蓝光光照对体外培养的人视网膜色素上皮(RPE)细胞凋亡的影响。方法用蓝光照射体外培养的人RPE细胞,分为3组,A组不同光照强度;B组同一光照强度,不同光照时间;C组同一光照强度和光照时间,不同细胞培养终止时间。利用末端脱氧核酸... 目的观察蓝光光照对体外培养的人视网膜色素上皮(RPE)细胞凋亡的影响。方法用蓝光照射体外培养的人RPE细胞,分为3组,A组不同光照强度;B组同一光照强度,不同光照时间;C组同一光照强度和光照时间,不同细胞培养终止时间。利用末端脱氧核酸转移酶介导的原位缺口末端标记(TUNEL)、荧光素标记的连接素V/碘化吡啶(Annexin V-FITC/PI)双染流式细胞检测、透射电子显微镜等手段观察细胞凋亡。结果TUNEL染色阳性细胞的体积缩小变圆,细胞核浓缩,边聚成新月形或帽状,细胞核碎裂成数个,细胞膜出胞。透射电子显微镜观察发现细胞内线粒体肿胀,线粒体内膜嵴消失;粗面内质网扩张;溶酶体增加,内含代谢产物。A组低于一定阈值[(500±100)lx]的蓝光光照对RPE细胞损伤较轻,细胞凋亡及坏死随光照强度的增强而增加;B组随着光照时间延长,RPE细胞凋亡数量没有增加,而细胞坏死逐渐增加;C组光照后6、12h,损伤以细胞凋亡为主,但随着光照时间延长,凋亡继发坏死细胞和坏死细胞明显增加。结论蓝光照射可引起体外培养的人RPE细胞损伤,损伤形式有凋亡、凋亡继发坏死及坏死;损伤程度呈光照强度和光照时间依赖性。 展开更多
关键词 眼损伤 色素上皮 细胞死亡 光刺激 临床实验室技术
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三峡水库香溪河库湾蓝藻水华暴发特性及成因探析 被引量:29
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作者 杨敏 张晟 胡征宇 《湖泊科学》 EI CAS CSCD 北大核心 2014年第3期371-378,共8页
2008年夏季,香溪河库湾自三峡水库建库以来第1次暴发蓝藻水华,水华波及整个库湾,持续时间达1个月之余.为了解这次水华暴发特性及发生原因,本文对蓝藻水华的发生发展过程进行了跟踪调查,6 7月水华发生期间每周采样1次.调查表明本次蓝藻... 2008年夏季,香溪河库湾自三峡水库建库以来第1次暴发蓝藻水华,水华波及整个库湾,持续时间达1个月之余.为了解这次水华暴发特性及发生原因,本文对蓝藻水华的发生发展过程进行了跟踪调查,6 7月水华发生期间每周采样1次.调查表明本次蓝藻水华的优势种为鱼腥藻(Anabaena sp.)、铜绿微囊藻(Microcystis aeruginosa)、惠氏微囊藻(Microcystis wesenbergii)等,细胞密度高达3.82×108cells/L,蓝藻相对密度达到90%以上.本文将2008年5 7月与2007年同期理化指标比较发现,2007年5月的N∶P为18.6,而2008年5月的N∶P较低,为6.2,据文献报道N∶P<8有利于微囊藻的复苏,因此2008年水华前期的低N∶P利于微囊藻的复苏,为微囊藻在适宜条件下的大量增殖提供了种源基础.方差分析表明,2008年5 7月各采样点真光层深度显著高于2007年同期,使得底泥中的微囊藻获得一定强度的光照而复苏,这可能是2008年蓝藻水华在香溪河库湾暴发的原因之一.综上所述,在具备充足的营养盐基础、较强的水体稳定性以及较高水温的前提下,香溪河库湾水华发生前期较低的N∶P以及较高强度的光照可能是微囊藻复苏的诱导因子,为蓝藻水华暴发提供了种源基础. 展开更多
关键词 香溪河库湾 三峡水库 蓝藻水华 N P 真光层深度
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大鼠光损伤性内层视网膜变性的超微病理学研究 被引量:20
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作者 张纯 王薇 《中华眼底病杂志》 CAS CSCD 2003年第4期222-225,共4页
目的 研究光损伤后大鼠眼内层视网膜的神经原变性。 方法 用波长为 4 80~ 5 2 0 nm,强度为 90 0~ 10 0 0 lx的绿光光照 L ewis大白鼠 2 4 h,然后使其在黑暗中恢复 ,于光照后 1、3、7、14 d处死动物并获得视网膜。以免疫组织化学方... 目的 研究光损伤后大鼠眼内层视网膜的神经原变性。 方法 用波长为 4 80~ 5 2 0 nm,强度为 90 0~ 10 0 0 lx的绿光光照 L ewis大白鼠 2 4 h,然后使其在黑暗中恢复 ,于光照后 1、3、7、14 d处死动物并获得视网膜。以免疫组织化学方法分别标记视网膜内层细胞 ,用光镜和电镜观察。 结果 光损伤后可见大量光感受器细胞死亡。杆双极细胞在光照后第 3天开始变性并逐渐减少数目 ;水平细胞在第 1天即水肿变性但以后逐渐恢复 ;无长突细胞在第 1天显示数目减少 ;神经节细胞在光照后始终呈水肿变性 ;Müller细胞于光照后在视网膜下增殖。超微结构研究显示视网膜内层神经元有固缩和水肿两种变性。 结论 视网膜内层神经元和 Müller细胞参与了光损伤性视网膜变性。不同的神经元表现不同类型的变性。 展开更多
关键词 大鼠 光损伤性 内层视网膜变性 超微病理学 疾病模型 病因学
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闪烁光对豚鼠眼球发育及近视形成的影响 被引量:19
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作者 程振英 李镜海 +1 位作者 李荣 谢英勃 《中华眼科杂志》 CAS CSCD 北大核心 2004年第9期601-604,共4页
目的 探讨闪烁光对豚鼠眼球发育及近视形成的影响。方法 将 30只 4周龄豚鼠随机分为 3组 ,Ⅰ组在闪烁光照明环境中饲养 ,闪烁方式为亮 2s,暗 2s;Ⅱ、Ⅲ组在日常照明环境中饲养 ,作为对照 ,Ⅱ组照明时间为每天 12h ,Ⅲ组照明时间为每天... 目的 探讨闪烁光对豚鼠眼球发育及近视形成的影响。方法 将 30只 4周龄豚鼠随机分为 3组 ,Ⅰ组在闪烁光照明环境中饲养 ,闪烁方式为亮 2s,暗 2s;Ⅱ、Ⅲ组在日常照明环境中饲养 ,作为对照 ,Ⅱ组照明时间为每天 12h ,Ⅲ组照明时间为每天 2 4h。 3组中光照度均为 2 0 0流明。实验 6周后分别用检影法测量眼屈光度 ,A超测量眼轴长度 ;摘除眼球 ,用电子天平测量眼球重量 ,在光学显微镜和透射电镜下观察眼球后极部巩膜、脉络膜和视网膜的组织学改变。结果 与对照组相比 ,在闪烁光照明环境中饲养的动物发生 - 7 0 0D的近视 ,眼轴增长 0 5 6mm ,眼球加重 6 8mg ,后极部巩膜细胞数量增多、活性增强、胶原纤维间隙扩大 ,脉络膜层变窄 ,视网膜感光细胞外节盘变短、排列不规则。结论 闪烁光能促进豚鼠眼球增长、诱导近视的形成。 展开更多
关键词 眼球发育 豚鼠 近视 巩膜 脉络膜 视网膜 对照组 结论 排列 照明环境
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可见光照对培养的人视网膜色素上皮细胞凋亡的影响 被引量:14
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作者 周咏东 严密 张军军 《中华眼底病杂志》 CAS CSCD 2002年第3期227-230,共4页
目的 研究可见光照对培养的人视网膜色素上皮 (retinal pigment epithelium,RPE)细胞凋亡的影响。 方法 以白色荧光灯为光源 ,用 5 0 0 lx、(2 0 0 0± 5 0 0 ) lx及 (340 0± 2 0 0 ) lx不同光照强度 ,按不同的光照时间 (... 目的 研究可见光照对培养的人视网膜色素上皮 (retinal pigment epithelium,RPE)细胞凋亡的影响。 方法 以白色荧光灯为光源 ,用 5 0 0 lx、(2 0 0 0± 5 0 0 ) lx及 (340 0± 2 0 0 ) lx不同光照强度 ,按不同的光照时间 (无光照、6、12、2 4 h)照射培养的人 RPE细胞。利用终末脱氧核糖核苷酸转移酶介导的原位缺口末端标记 (terminal deoxynucleotidyl transferase mediated d UTP nick end labelling,TUNEL)、荧光素标记的连接素 V/碘化丙锭 (Annexin V- fluorescein isothiocyanate/ Propidium iodium,AnnexinV- FITC/ PI)双染色流式细胞测定、相差倒置显微镜等手段观察 RPE细胞凋亡 (分为光照后 6、12、2 4、36 h组 )。 结果 可观察到 RPE细胞出现两种死亡形式 ,凋亡与坏死。 (1)低于一定阈值 (5 0 0 lx)的光照对细胞损伤较轻 ,细胞凋亡及坏死随光照强度的增加而增加。 (2 )在较短的光照时间 (6 h和 12 h)内 ,细胞死亡的增加以凋亡为主 ;随着光照时间的延长 ,细胞坏死逐渐明显。 (3)随着光照后培养时间的延长 ,细胞凋亡明显增加 (P<0 .0 5 )。光照后 6、12、2 4 h的损伤改变以凋亡为主 ,但随时间的延长 ,凋亡继发性坏死的增加显著。光照后 36 h,细胞的坏死数显著增高 (P<0 .0 1)。 结论 可见? 展开更多
关键词 可见光照 培养 人视网膜色素上皮 细胞凋亡
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表面裂纹长度的测量方法 被引量:17
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作者 张利娟 张亚军 高灵清 《材料开发与应用》 CAS 2009年第5期75-79,共5页
表面裂纹长度的精确测量是准确获得表面裂纹扩展速率进而对材料或构件进行剩余寿命评估的基础和关键技术问题。本文将表面裂纹长度的测量方法归类为直读法、柔度法、电位法、探伤法和光学法,并对每种方法进行了介绍,比较其优缺点及适用... 表面裂纹长度的精确测量是准确获得表面裂纹扩展速率进而对材料或构件进行剩余寿命评估的基础和关键技术问题。本文将表面裂纹长度的测量方法归类为直读法、柔度法、电位法、探伤法和光学法,并对每种方法进行了介绍,比较其优缺点及适用范围,以便在实际工作中选择应用。 展开更多
关键词 表面裂纹长度 测量方法 直读法 柔度法 电位法 探伤法 光学法
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