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1.
视网膜光化学损伤动物模型是研究视网膜变性类疾病的良好模型,研究发现凋亡是视网膜感光细胞光化学损伤以及其它视网膜变性疾病感光细胞丢失的主要机制。本文阐述了核转录因子κB(NFκB)体系,arrestin蛋白家族,AP-1和神经营养因子受体P75NTR等调控感光细胞凋亡的分子机制。 (中华眼底病杂志,2004,20:396-398)  相似文献   

2.
挫伤性视网膜病变感光细胞凋亡的实验观察   总被引:4,自引:0,他引:4  
目的 观察挫伤性视网膜病变感光细胞凋亡情况。方法 以3J的能量自由落体的方式造成兔眼挫伤性视网膜病变模型,通过光、电镜及末端脱氧核苷酸转移酶介导的生物素化dUTP(脱氧三磷酸尿苷)缺口末端标记(teminal deoxynucleotidyl transferase-mediated dUTP nick endlabeling,TUNEL)染色观察视网膜病变及感光细胞凋亡情况。结果 以3J的能量挫伤后的视网膜病变中存在着感光细胞凋亡现象。结论 细胞凋亡是挫伤性视网膜病变的一个重要机制。  相似文献   

3.
目的研究小胶质细胞活化与rd小鼠遗传性视网膜变性的关系。方法对出生后8、10、12、14、16及18d的rd小鼠及对照小鼠视网膜进行感光细胞凋亡TUNEL法检测及形态计量学分析。CD11b免疫组织化学染色标记视网膜小胶质细胞。结果rd小鼠出生后10d视网膜感光细胞层开始出现TUNEL染色阳性细胞,第16d达到高峰。视网膜小胶质细胞在rd小鼠出生后10d开始活化,第14d达到高峰。小胶质细胞向感光细胞层的迁移与感光细胞凋亡之间存在紧密的时间和空间关系。结论rd小鼠视网膜变性以感光细胞凋亡为主。小胶质细胞活化可能在视网膜变性过程中发挥重要作用。  相似文献   

4.
视网膜感光细胞的药物干预研究   总被引:1,自引:0,他引:1  
视网膜变性疾病累及感光细胞,以感光细胞的渐进性凋亡以及死亡为结局。对感光细胞进行药物干预是治疗这类疾病的一种方法和途径。多种神经营养因子有保护感光细胞,延缓其凋亡的作用;牛磺酸是一种条件必需氨基酸,在视网膜感光细胞的发育和分化过程中起重要作用;DHA是唯一能减少感光细胞凋亡数目的多不饱和脂肪酸;多种维生素以及一些蛋白质也对感光细胞有保护作用。本就这些物质单独和/或联合干预感光细胞作用研究现状及进展作一介绍。  相似文献   

5.
中药复方制剂对rds小鼠感光细胞凋亡的干预作用研究   总被引:4,自引:0,他引:4  
目的观察中药复方制剂对先天性视网膜变性小鼠视网膜感光细胞凋亡的影响。方法以黄芪等药组成复方制剂1。对先天性视网膜变性动物模型rds小鼠,采用原位末端转移酶标记(TUNEL)方法及组织病理学技术,观察复方制剂1作用后,小鼠视网膜感光细胞数量及感光细胞凋亡的变化。结果仔鼠2周时,中药组小鼠视网膜感光细胞核数与对照组相比无明显差别,两组感光细胞凋亡率分别为1.6%及6.5%,组间差异有显著性(P<0.01);4周时中药组感光细胞核数目较对照组多,差异有显著统计学意义(P<0.01),两组感光细胞凋亡率分别为3.3%及8.5%,组间差异有显著统计学意义(P<0.01)。结论中药复方制剂1可以延缓rds小鼠视网膜色素变性过程中感光细胞凋亡的发展。  相似文献   

6.
刘波 《眼科学报》2020,(2):106-112
视网膜变性是导致眼睛永久失明的主要原因之一,其特征是视网膜感光细胞的丧失,而感光细胞的丧失主要通过凋亡途径。近年来,虽然感光细胞的凋亡机制研究已经引起了重视,但目前仍缺乏有效的方式来抑制感光细胞凋亡。因此,本文将从凋亡的进程、凋亡发生过程中的关键分子、凋亡通路以及凋亡和自噬的联系等方面对其进行综述,旨在进一步阐明感光细胞凋亡的分子机制。  相似文献   

7.
视网膜感光细胞的凋亡与保护   总被引:3,自引:0,他引:3  
许多视网膜变性疾病,尽管其发病机制和临床特点不同,但最终均以感光细胞的凋亡而引起不可逆的视力丧失。本文阐述了细胞凋亡的共同通路:Caspase激活的酶促反应;同时分析了感光细胞凋亡与AP-1因子的关系,并进一步对感光细胞变性特点及bFGF、DHA的保护作用一综述。  相似文献   

8.
视网膜感光细胞的凋亡与保护   总被引:1,自引:0,他引:1  
许多视网膜变性疾病,尽管其发病机制和临床特点不同,但最终均以感光细胞的凋亡而引起不可逆的视力丧失。近年来,人们对细胞凋亡的发生机制有了进一步的认识,本文阐述了细胞凋亡的共同通路:Caspase 激活的酶促反应;同时分析了感光细胞凋亡与AP1 因子的关系,并进一步对感光细胞变性特点及bFGF、DHA 的保护作用作一综述。  相似文献   

9.
李根林  孙异临  王津津  曲宝清  王景昭 《眼科》2003,12(3):167-170,T012
目的:了解新生期小牛视网膜感光细胞联系和细胞连接特征。方法:以新生期小牛视网膜感光细胞为研究对象,扫描电镜和透射电镜为研究手段,实验共用眼球6个,取视网膜24片。结果:新生期小牛视网膜感光细胞胞体平均直径3-5μm。近外核层外侧端,感光细胞间有束状纤维联系;近外核层内侧端,多个感光细胞通过网状纤维形成多种联系,纤维平均直径:0.3—0.6μm。部分感光细胞通过束状纤维呈“会聚式”联系,束状纤维主干平均直径:0.65~0.75μm,分支平均直径:0.25-0.5μm。感光细胞与中间传导细胞建立缝隙连接,部分具备典型结构,缝隙间隙宽度:3-5nm,但大部分感光细胞与中间传导细胞的细胞连接结构尚不成熟。结论:新生期视网膜感光细胞已具有分化和参与功能构建能力,适宜作为视网膜移植供体选材。  相似文献   

10.
目的探讨视网膜光损伤后感光细胞病理学改变的特征及其发生机制。方法以白色强光持续照射的方法制成大鼠视网膜光损伤模型并采用常规HE染色与TUNEL技术对光损伤后视网膜感光细胞的病理学改变进行动态观察研究。结果白色强光照射后视网膜感光细胞发生进行性的变性,TUNEL标记结果显示光损伤后视网膜外核层出现大量阳性着色细胞。结论持续高强度白光照射可选择性地导致视网膜感光细胞发生进行性的变性而凋亡是感光细胞退行性变性的重要发生机制。  相似文献   

11.
Individual properties of a viscoelastic substance for ophthalmologic applications are intimately tied to its chemical and rheologic characteristics. Independent comparative data for vicoelastic substances are not readily available or interpretable. Material and methods: Twenty-six different commercially available viscoelastic substances were investigated using the Advanced Rheometric Expansion System and the Rheometric Scientific 800 device to analyze elastic and viscous modulus, complex viscosity (dynamic frequency dependance) and viscosity at the zero shear rate by extrapolation using the Ellis fit. Results: Viscosity (cps) at zero shear rate (s–1, mean of six different samples): Sodium hyaluronate products: Amivisc Plus: 128; AMO Vitrax: 41; Biolon: 243; Dispasan: 130; Dispasan Plus: 782; Healon: 243; Healon GV: 2451; Healon 5: 5525; Microvisc (Morcher Oil): 1162; Microvisc Plus: 3663; Morcher Oil: 1253; Provisc: 207; Rayvisc: 78; Viscoat: 58; Viscorneal (Allervisc): 733; Viscorneal Plus (Allervisc Plus): 1176; Visko: 206; Visko Plus: 1683. Hydroxypropylmethylcellulose (HPMC) products: Acrivisc: 7; Adatocel: 8; Coatel: 6; HPMC Ophthal H: 94; HPMC Ophthal L: 7; Ocucoat: 6; PeHa-Visko: 5; Visco Shield: 60. Conclusion: Sodium hyaluronate as well as HPMC viscoelastic substances demonstrated remarkable differences in rheological properties from each other. In some cases, the results of this independent investigation differed from the values provided by the companies. A new division of commercially available viscoelastic substances into subgroups is presented, which provides a scientific base for various practical viscosurgical aspects. These real rheologic properties of each substance allow the ophthalmic surgeon to choose the viscoelastic substance that is most suitable for the surgical situation.  相似文献   

12.
Individual properties of a viscoelastic substance for ophthalmologic applications are intimately tied to its chemical and rheologic characteristics. Independent comparative data for vicoelastic substances are not readily available or interpretable. MATERIAL AND METHODS: Twenty-six different commercially available viscoelastic substances were investigated using the Advanced Rheometric Expansion System and the Rheometric Scientific 800 device to analyze elastic and viscous modulus, complex viscosity (dynamic frequency dependance) and viscosity at the zero shear rate by extrapolation using the Ellis fit. RESULTS: Viscosity (cps) at zero shear rate (s-1, mean of six different samples): Sodium hyaluronate products: Amivisc Plus: 128; AMO Vitrax: 41; Biolon: 243; Dispasan: 130; Dispasan Plus: 782; Healon: 243; Healon GV: 2451; Healon 5: 5525; Microvisc (Morcher Oil): 1162; Microvisc Plus: 3663; Morcher Oil: 1253; Provisc: 207; Rayvisc: 78; Viscoat: 58; Viscorneal (Allervisc): 733; Viscorneal Plus (Allervisc Plus): 1176; Visko: 206; Visko Plus: 1683. Hydroxypropylmethylcellulose (HPMC) products: Acrivisc: 7; Adatocel: 8; Coatel: 6; HPMC Ophthal H: 94; HPMC Ophthal L: 7; Ocucoat: 6; PeHa-Visko: 5; Visco Shield: 60. CONCLUSION: Sodium hyaluronate as well as HPMC viscoelastic substances demonstrated remarkable differences in rheological properties from each other. In some cases, the results of this independent investigation differed from the values provided by the companies. A new division of commercially available viscoelastic substances into subgroups is presented, which provides a scientific base for various practical viscosurgical aspects. These real rheologic properties of each substance allow the ophthalmic surgeon to choose the viscoelastic substance that is most suitable for the surgical situation.  相似文献   

13.
陈建华  徐亮 《国际眼科杂志》2010,10(6):1073-1078
目的:评价GDx检测RNFL厚度各参数的敏感性,特异性,准确性,阳性预测值,阴性预测值,阳性似然比,阴性似然比;比较正常人和青光眼患者GDx各参数的不同;确定GDx参数对青光眼早期诊断最有价值的指标和GDx早期诊断青光眼的能力。方法:用GDx对94例188眼正常人和88例173眼青光眼患者RNFL进行检测。将青光眼患者按视野的平均缺损程度分为早、中晚期青光眼两组。用t-test和方差分析,比较正常人RNFL参数与早、中晚期青光眼的不同;绘制GDx参数ROC曲线,比较GDx参数中ROC曲线下面积的大小;用逐步判别分析确定GDx参数中对早期青光眼诊断最有意义的指标。结果:正常人94例,平均年龄为:41.7±8.5岁;青光眼(早、中晚期)患者平均年龄:52.8±14.6岁。早期青光眼122眼,中晚期青光眼51眼,视野平均缺损(meandefect,MD;Octopus1-2-3自动视野计测量)为-1.6~23.2dB。正常人RNFL各参数与各期青光眼患者比较差异有非常显著意义(P<0.01)。GDx的TSNIT参数的敏感性和特异性为:74.0%和74.0%,准确性:86.8%,阳性预测值:73.0%,阴性预测值:76.0%,阳性似然比:2.96,阴性似然比:0.33。SA参数的敏感性和特异性为:71.1%和84.6%,准确性为77.5%,阳性预测值:80.9%,阴性预测值:76.1%,阳性似然比:4.62,阴性似然比:0.34。IA参数的敏感性和特异性为:76.3%和82.4%,准确性:78.8%,阳性预测值:80.0%,阴性预测值:79.1%,阳性似然比:4.34,阴性似然比:0.35。NFI参数的敏感性和特异性为:80.3%和67.0%,准确性:73.4%,阳性预测值:69.2%,阴性预测值:78.8%,阳性似然比:2.43,阴性似然比:0.29。GDx的TSNIT和NFI两个参数综合评价的敏感性和特异性为:76.3%和74.0%,准确性:93.3%,阳性预测值:87.7%,阴性预测值:63.2%,阳性似然比:3.05,阴性似然比:0.32。GDx两个参数综合评价时,NFI+IA结合评价的敏感性最高(88.4%),特异性最高的是SA+IA(84.6%)。如果NFI+TSNIT+SA+IA综合评价其敏感性和特异性达最高,分别是86.7%和85.6%。在特异性相同的情况下,GDx诊断早期青光眼的敏感性为66.4%,准确性:58.5%,阳性预测值:92.0%,阴性预测值:77.5%,阳性似然比:2.56,阴性似然比:0.45。中晚期青光眼诊断的敏感性为:86.3%,准确性:77.4%,阳性预测值:48.4%,阴性预测值:95.3%,阳性似然比:3.45,阴性似然比:0.18。GDx的NFI≥20时,敏感性和特异性分别为78.3%和78.7%,准确性为78.7%,阳性预测值为77.3%,阴性预测值为80.0%,阳性似然比为3.68,阴性似然比为0.28。GDx的NFI≥23时,敏感性和特异性为75.1%和84.0%,准确性为79.8%,阳性预测值为81.3%,阴性预测值为74.9%,阳性似然比为4.69,阴性似然比为0.30。GDx的NFI≥27时,敏感性和特异性分别为64.7%和91.0%,准确性为35.7%,阳性预测值为86.8%,阴性预测值为73.7%,阳性似然比为7.19,阴性似然比为0.39。GDx各参数ROC曲线下面积分别为NFI:0.84,IA:0.79,TSNIT:0.78,SA:0.77,IES:0.76。通过逐步判别分析,筛选出NFI和IA对区分早期青光眼贡献最大(F检验:P<0.01),用IA和NFI进行分析,诊断早期青光眼的敏感性和特异性分别为:88.4%和74.6%。结论:GDx为临床上提供定量检测视网膜神经纤维层厚度参数;NFI和IA是区分正常人和早期青光眼最有效指标。GDx可有助于临床上青光眼的早期诊断。  相似文献   

14.
Phospholipid molecular species of frog rod outer segment membranes   总被引:6,自引:0,他引:6  
Phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were isolated from frog retinal rod outer segment (ROS) membranes and their major molecular species determined. Saturated fatty acids are predominantly located on position-1 and polyunsaturates on position-2, although this assignment is not absolute. One-fifth of the species of PC are of the saturated and monoenoic type, compared to only trace amounts of these species in PE. On the other hand, PE contains at least 50% dipolyunsaturated species, while PC has 6%. The predominant molecular species of frog PC are: 18:0-22:6 omega 3 (39%), 16:0-22:6 omega 3 (17%), 16:0-16:1 (6%), 16:0-18:1 (5%) and 16:0-16:0 (4%). The major molecular species of frog PE are: 22:6 omega 3-22:6 omega 3 (21%), 18:0-22:6 omega 3 (18%), 18:1-22:6 omega 3 (14%), 22:4 omega 6-22:6 omega 3 (10%), 22:5 omega (3 + 6)-22:6 omega 3 (10%), 16:0-22:6 omega 3 (7%) and 20:4 omega 6-22:6 omega 3 (5%). The specific molecular species are discussed in relation to their effect on fluidity and asymmetry of ROS disc membranes.  相似文献   

15.
Objective: To report the clinical and pathologic features of an elderly patient with a unilateral orbital swelling and proptosis caused by Juvenile Xanthogranuloma diagnosed and confirmed by orbital biopsy.

Design: Interventional case report.

Participants: One patient.

Intervention: Steroids (Medrol dose pack) and radiation.

Main Outcome Measures: Unusual clinical presentation and pathological features of Juvenile Xanthogranuloma in the orbit.

Conclusions: Juvenile Xanthogranuloma affecting one orbit is very rare with unilateral involvement in an elderly patient. Steroids and radiation therapy were very effective in treatment and provided impressive results.  相似文献   


16.
Purpose: To evaluate the results from the correction of ectropion of the punctum lacrimale in lower eyelids with a new surgical clamp.

Design: Prospective study.

Methods: Eighty eight eyelids in 55 patients with mild and moderate ectropion were included in the study. An excision of a diamond of tarso-conjunctiva with retractor reattachment and concomitant correction of horizontal lid laxity, if present, was performed.

Results: Resolution of tearing was obtained in 77 eyes. In 11 eyes, persistent tearing was reported.

Conclusion: Conclusion:Conclusion: Repair of early to intermediate ectropion of the lacrimal punctum using the Raus–Garito clamp is associated with a good functional and cosmetic outcome.  相似文献   


17.
Abstract

Purpose: To investigate the intraocular pressure (IOP) and ocular perfusion pressure (OPP) in night shift workers. Methods: Seventy-one healthy individuals who work the night shift were evaluated. IOP and OPP were measured in the sitting position in each participant. Measurements were obtained at rest time (09:00, 12:00, 16:00) and night-shift time (20:00, 24:00, 04:00, 08:00). Results: The mean age of the 33 females and 38 males was 35.6?±?7.5 years (range 20-53 years). Mean IOP values were different between the measurements at 9:00 and 12:00 (p?=?0.00), at 9:00 and 16:00 (p?=?0.00), at 12:00 and 16:00 (p?=?0.00), at 16:00 and 24:00 (p?=?0.02), at 24:00 and 04:00 (p?=?0.02), and at 24:00 and 08:00 (p?=?0.00). Mean OPP values were significantly different only between the measurements at 9:00 and 20:00 (p?=?0.01). Conclusion: This study revealed that IOP and OPP in night shift workers show 24-hour variations.  相似文献   

18.
Purpose: To report the use of flow cytometry on aqueous fluid to diagnose sarcoidosis in a patient with recurrent granulomatous anterior uveitis.

Methods: Case report.

Results: Flow cytometry on aqueous fluid demonstrated a CD4/CD8 ratio >9.5, consistent with a diagnosis of sarcoidosis.

Conclusions: Flow cytometry on aqueous fluid may offer an additional pathway for diagnosing sarcoid anterior uveitis.  相似文献   


19.
Purpose: To elucidate the usefulness of abnormal liver function tests in the diagnosis of sarcoidosis in patients presenting with ocular inflammation.

Methods: Retrospective comparison of sample populations of 100 patients each with sarcoidosis-associated uveitis (SAU) and non-sarcoid uveitis controls.

Results: Number of abnormal results between SAU and control groups were: (1) raised alkaline phosphatase 6:2; (2) raised alanine aminotransferase 21:19; (3) raised total protein 14:5; (4) hypoalbuminemia 0:7; (5) raised bilirubin 1:2. The only parameters reaching statistical significance were in (3), using any elevated result; and (4), the greater risk being in controls.

Conclusions: There is no evidence that abnormal liver function tests are an indicator of sarcoidosis in new patients presenting with uveitis.  相似文献   


20.
PurposeThe molecular basis of the tear film and lipid layer alterations in meibomian gland dysfunction (MGD) is unknown. This study aimed to identify and compare (O-acyl)-omega-hydroxy fatty acids (OAHFAs) derived from human meibum and tears in MGD.MethodsOf 195 eligible subjects (18–84 years, 62.6% female), 183 and 174 provided samples for tears and meibum, respectively. Subjects were classified into four groups: Normal, Asymptomatic MGD, MGD, and Mixed. Samples from the right eye of each subject were infused into the SCIEX 5600 TripleTOF mass spectrometer in negative ion mode. Lipid intensities identified with Analyst1.7 TF and SCIEX LipidView1.3 were normalized by an internal standard and total ion current, then statistically compared in MetaboAnalyst 4.0.ResultsIn meibum and tears, 76 and 78 unique OAHFAs were identified, respectively. The five most frequent and abundant OAHFAs were 18:2/16:2, 18:1/32:1, 18:1/30:1, 18:2/32:1, and 18:1/34:1. Two OAHFAs, 18:2/20:2 and 18:2/20:1, were identified only in tears. Initial univariate analysis revealed three differently regulated OAHFAs in meibum and eight in tears. Partial Least Square Discriminant Analysis showed 18:1/32:1, 18:2/16:2, 18:1/34:1 and 18:0/32:1 in tears, and 18:2/16:2, 18:1/32:1 and 18:2/32:2 in meibum, had variable importance in projection scores >1.5 and contributed the most to the separation of groups. In both meibum and tears, all OAHFAS except 18:2/16:2 were reduced in MGD compared to the normal group.ConclusionMGD is accompanied by differential expression of specific OAHFAs in meibum and tears. These results suggest OAHFAs play a role in the altered biochemical profile of the tear film lipid layer in humans with MGD.  相似文献   

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