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31.
Watanabe Y.; Yuzawa Y.; Mizumoto D.; Tamai H.; Itoh Y.; Kumon S.; Yamazaki C. 《Nephrology, dialysis, transplantation》1993,8(8):725-734
We studied the long-term outcome of 268 patients suffering fromdiabetic end-stage renal disease (DM-ESRD) treated with long-termhaemodialysis between 1978 and 1991, with special emphasis onvisual acuity as well as the heterogeneity of DM-ESRD The 50%patient survival on haemodialysis was 60 months. Visual disturbanceswere found in 73.1% (392/536) of eyes at the start of haemodialysis.Chronological assess ment of visual acuity demonstrated thestabilization of visual acuity and 87.1% (364/418) of eyes werestable, 4.8% (20/418) were improved, and 8.1% (34/418) wereaggravated in the long term respectively. The change of visualacuity was frequently seen in the short term, and rapid shiftsof body fluid to correct overhydration induced abrupt changesof glycaemic control as well as retraction of macular oedema.Hence it might be one of the factors affecting rapid changeof visual acuity in the short term. Meanwhile, long-term deterioration of visual acuity resulted from either hyperten sionunresponsive to medical treatment or poor glycaemic control.Some DM-ESRD patients had only background retinopathy at thestart of haemodialysis and these were likely to have the nephroscleroticglomerular lesion. They were old, not nephrotic and had a milddegree of diabetes during the predialysis stage. Thus, DM-ESRDpatients seem to have some heterogeneity in their clinical characteristics,and old DM-ESRD patients with only background retinopathy havethe appearance of diabetic macroangiopathy rather than microangiopathy. 相似文献
32.
背景 近年来,人工智能(AI)在医学领域发展迅速,在糖尿病视网膜病变(DR)中的应用范围不断扩展。目的 通过文献计量分析总结AI在DR领域的应用情况,阐明AI在DR领域相关研究的现状、热点和新兴趋势,以期为未来的研究提供思路。方法 以Web of Science数据库为来源,检索建库至2022-11-04的AI应用于DR领域的相关文献,运用CiteSpace软件对纳入文献进行发文量、国家、机构、作者、共被引和关键词的文献计量学分析。结果共获得1 770篇文献,2011年1月至2022年11月发文量总体呈上升趋势,2021年发文量达峰值(402篇)。中国是发文量(440篇)位居第1的国家,英国为中心性(0.26)最高的国家。机构合作网络图谱共纳入436家机构,以中山大学和首都医科大学为代表。作者合作网络图谱共纳入601位作者,以JIA Y L和HWANG T为代表。GULSHAN V、ABRàMOFF M D与TING D W 3位高被引作者对该领域做出了重要贡献。Ophthalmology、Invest Ophth Vis Sci和Ieee T Med Imaging是AI应用于DR领... 相似文献
33.
Pierre Lachapelle Julie Benoit John M. Little Jocelyn Faubert 《Documenta ophthalmologica. Advances in ophthalmology》1989,73(4):327-336
Of all the electroretinogram (ERG) components (a-wave, b-wave, and oscillatory potentials) only one oscillatory potential, OP2, was found to be significantly correlated with the absolute intensity of the flash stimulus (i.e., the intensity of the stimulus irrespective of the state of retinal adaptation). Our finding was further confirmed in single cell recordings of lateral geniculate unit activity in rabbits in which peak time of OP2 was found to correlate better with the geniculate activity. For these reasons we have identified OP2 as the intensity coding oscillatory potential of the ERG. In order to investigate if this new feature could have some clinical significance, we examined photopic ERGs recorded from patients affected with various retinopathies. In most instances the peak time of OP2 paralleled that of the b-wave, that is, in the ERG with delayed b-wave the peak time of OP2 was also delayed, while in ERGs with normal b-wave peak time the peak time of OP2 was also normal. However, in some conditions (especially in cone-rod diseases) a delayed OP2 was found in ERGs with normal b-wave peak times. 相似文献
34.
I. Gottlob F. H. Prskavec N. Stelzer I. Hienert H. Weghaupt T. M. Radda 《Documenta ophthalmologica. Advances in ophthalmology》1989,72(2):105-113
Visual acuity, color vision, pattern-visual-evoked-potentials (P-VEPs) and pattern-electroretinograms (P-ERGs) were measured in 13 diabetic subjects before, and 24 hours and 5 weeks after blue-green argon laser treatment. As control, the same examinations were performed in 7 normal subjects and 7 diabetic patients before and after slit lamp examination with the Goldman three mirror contact lens.Visual acuity and P-ERG amplitudes were significantly reduced one day after the laser treatment, while 5 weeks after the laser coagulation, visual acuity and P-ERG amplitudes recovered to pretreatment values. The control group showed no significant changes after slit lamp examination. Since fluorescein angiography revealed no macular changes after laser treatment, the possibility of a reversible functional light damage after blue-green argon laser coagulation (ALC) is discussed.This study was supported by the Medizinisch - Wissenschaftlicher Fonds des Bürgermeisters der Bundeshauptstadt Wien. 相似文献
35.
Motomaro Nakajima Hiroyuki Narnbu Nobuaki Shikata Hideto Senzaki Hirohiko Miki Airo Tsubura 《Pathology international》1996,46(11):874-882
Pigmentary degeneration of the retina was induced by a single intraperitoneal Injection of 75mgkg of N-methyl-N-nitrosourea (MNU) In female Brown-Norway colored rats at 50 days of age, which were then observed at 24, 48 and 72 h and 7, 21,35 and 150 days after the treatment. MNU-treated rats showed selective destruction of the photoreceptor cells by an apoptotic mechanlsm 24 h after the treatment, and the destruction was completed by day 7. During the photoreceptor cell degeneration, proliferation of Miller cells and infiltratlon of macrophages was prominent 72h and 21 days aRttr the treatment, respectively. Müller cell proliferation and macrophage infiltratbn corresponded to degenerative photo-receptor cell phagocytosis, and prollferating Müller cell processes responded to stabilize the damaged retina. Pigment epithelial cell detachment from the Bruch's membrane was seen 72 h after the treatment, and migration within all layers of the retina was seen at day 7 when photoreceptor Cells were lost. At 21, 35 and 150 days after the treatment, lack of photoreceptor cells and deposition of pigment epithelial cells within the retina but not in contact to vascular endothe-lial cells were characteristic. MNU-induced photoreceptor apoptosis followed by Miiller cell and macrophage reaction then pigment epithellal cells deposition withln the retina partially resembles retinitis pigmentosa in humans. 相似文献
36.
糖尿病大鼠视网膜基因表达谱差异的初步分析 总被引:5,自引:1,他引:5
目的 建立大鼠正常视网膜和糖尿病8周视网膜基因表达谱,比较两者差异,初步分析糖尿病视网膜病变的相关基因。方法 通过限制片段差异显示 PCR( restriction fragments differential display-PCR,RFDD-PCR)获得正常大鼠视网膜及8周糖尿病大鼠视网膜组织转录组片段。应用Fraent Analysis等软件,对差异片段进行生物信息学分析,初步确定糖尿病视网膜病变相关基因/表达序列标签( expression sequence tag, Ksr)。结果 获得有意义的片段共3639个,有差异的片段840个,占表达数的23.08%。其中包括5个视觉传导相关基因,13个兴奋性神经递质受体基因和3个抑制性神经递质受体基因。糖尿病8周大鼠视网膜Rhodopsin kinase,β-arrestin,Phosducin, rod photoreceptor cGMP-gated channel 和 Rpe65的表达下调,离子型谷氨酸受体iGluR1-4下调,代谢性谷氨酸受体及γ-氨基丁酸受体各亚型则普遍上调,而甘氨酸受体表达无变化。结论 糖尿病8周大鼠神经视网膜已受到累及,其基因表达模式的改变,可能与糖尿病早期视功能损害有关。 相似文献
37.
Elena R. Schiff Malena Daich Varela Anthony G. Robson Karen Pierpoint Rola Ba‐Abbad Savita Nutan Wadih M. Zein Ehsan Ullah Laryssa A. Huryn Sari Tuupanen Omar A. Mahroo Michel Michaelides Derek Burke Katie Harvey Gavin Arno Robert B. Hufnagel Andrew R. Webster 《American journal of medical genetics. Part C, Seminars in medical genetics》2020,184(3):631-643
Pathogenic variants in the gene HGSNAT (heparan‐α‐glucosaminide N‐acetyltransferase) have been reported to underlie two distinct recessive conditions, depending on the specific genotype, mucopolysaccharidosis type IIIC (MPSIIIC)—a severe childhood‐onset lysosomal storage disorder, and adult‐onset nonsyndromic retinitis pigmentosa (RP). Here we describe the largest cohort to‐date of HGSNAT‐associated nonsyndromic RP patients, and describe their retinal phenotype, leukocyte enzymatic activity, and likely pathogenic genotypes. We identified biallelic HGSNAT variants in 17 individuals (15 families) as the likely cause of their RP. None showed any other symptoms of MPSIIIC. All had a mild but significant reduction of HGSNAT enzyme activity in leukocytes. The retinal condition was generally of late‐onset, showing progressive degeneration of a concentric area of paramacular retina, with preservation but reduced electroretinogram responses. Symptoms, electrophysiology, and imaging suggest the rod photoreceptor to be the cell initially compromised. HGSNAT enzymatic testing was useful in resolving diagnostic dilemmas in compatible patients. We identified seven novel sequence variants [p.(Arg239Cys); p.(Ser296Leu); p.(Phe428Cys); p.(Gly248Ala); p.(Gly418Arg), c.1543‐2A>C; c.1708delA], three of which were considered to be retina‐disease‐specific alleles. The most prevalent retina‐disease‐specific allele p.(Ala615Thr) was observed heterozygously or homozygously in 8 and 5 individuals respectively (7 and 4 families). Two siblings in one family, while identical for the HGSNAT locus, but discordant for retinal disease, suggest the influence of trans‐acting genetic or environmental modifying factors. 相似文献
38.
糖尿病及其并发症病是全世界关注的重大公共卫生问题。糖尿病微血管病变是糖尿病虚损夹血瘀形成的血管并发症,以微循环障碍并伴有透明样物质沉积为基本病理改变特征,糖尿病肾病、糖尿病视网膜病变和糖尿病神经病变最为常见。糖尿病微血管病变可追溯到糖尿病前期,随着糖尿病发生发展动态演进不断加重,需及早干预。临床在降糖、降脂、降压的基础治疗上,多选择抗氧化应激、抗炎、改善微循环和抗血管新生的药物治疗糖尿病微血管并发症。糖尿病微血管病变属于中医“络病”的概念,中药治疗糖尿病微血管病变的核心是在降糖的基础上保护“孙络-微血管”,组方多为补气滋阴、清热活血药味配伍而成。该文基于糖尿病微血管病变的中西医认识及治疗原则,简要概述针对不同证型治疗糖尿病微血管病变的常用方剂,如白虎加人参汤、玉液汤、四妙勇安汤、葛根芩连汤、六味地黄丸及一些现代制剂,同时概述方剂常用药味,如人参、黄芪、地黄、枸杞子、三七、丹参、金银花、葛根的研究进展,以期为中药治疗糖尿病微血管病变提供临床依据和理论指导。 相似文献
39.
目的:研究玻璃体视网膜手术的主要致病。方法:对449例玻璃体视网膜手术做回顾性分析,男243例,女206例,术前视力光感-0.2;平均病史11.6月,手术采用三切口闭合式玻璃体切割术,结果:449例诊断明确,与术前诊断符合率为80.6%,病因中视网膜血管性疾病114例,占25.39%,眼外伤85例,占18.93%,糖尿病视网膜病变82例,占18.26%,黄斑部病变41例,占9.13%,孔源性视网膜脱离39例,占8.69%,眼内炎25例,占5.57%,结论:玻璃体视网膜手术正走向成熟,其适应证逐渐扩展,已成为治疗眼后段疾病的重要手段。 相似文献
40.
高血压性视网膜病变的视觉电生理改变探讨 总被引:3,自引:0,他引:3
目的:探讨高血压性视网膜病变的闪光视网膜电网(FERG),振荡电位(OPs)改变,方法:比较正常对照组15例30只眼和不同眼底分毋组的原发性高血压病患者,共49例98只眼的FERG,OPs的变化。结果:1.FERG:a波潜伏期:对照组与I级组相比差异无显著性,与Ⅱ,Ⅲ级组相比差异均有显著性;I级组与Ⅱ级组间差异无显著性,但I级与Ⅲ级,Ⅱ级与Ⅲ级组间差异均有显著性;a波振幅:对照组与I级组间差异无显著性,与其他各组间差异均有显著性;各级患者组间差异均有显著性;b波潜伏期,除I级与II级组间差异无显著性外,其余各组间差异均显著;b波振幅;除对照组与I级组间差异无显著性外,其余各组间差异均有显著性,2.OPs潜伏期:对照组各子波与I级组以及OP1,OP4及Ⅱ级组间差异无显著性,与其他各组间差异均有显著性,I级各子波与II级组间差异无显著性,与Ⅲ级组间差异显著,Ⅱ级与Ⅲ级组间差异显著。OPs振幅:对照组OP3与I级组间差异无显著性,其余比较差异均有显著性,除I级与Ⅱ级组间的OP4振幅差异无显著性外,各级患者组间的各子波振幅以及总振幅差异均有显著性。结论:FERG,OPs可作为高血压性视网膜病变及其严重程度的客观定量指标。 相似文献