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81.
为探讨、分析氩激光治疗视网膜阻塞新生血管的疗效。氩激光治疗视网膜静脉塞新生血管55例,中央静脉塞行全视网膜光凝。分支静脉阻塞区域播散性光凝,光斑200-500μm,时间0.1-0.2s,能量0.12-0.4w,Ⅱ级光斑,蓝绿色光波,黄斑格栅光凝光斑100μm,时间0.1s,能量视病情而定,以Ⅰ级反应为度,绿色光波。结果:55例中44例有效,新生儿血管消嫁总有效率80%,无效11例(其中视盘有新生血  相似文献   
82.
目的:研究视网膜光化学损伤状况下视紫红质基因mRNA表达水平的变化规律及其与形态学改变的关系。 方法:应用原位杂交和电镜技术对光化学损伤大鼠视网膜视紫红质基因mRNA表达情况及视网膜形态学损伤性改变进行动态观察。 结果:视紫红质mRNA原位杂交信号主要分布于视网膜光感受细胞层,尤其是其内段和外段;随连续光照时间的延续,其表达迅速下降,且先于视网膜形态学的损伤性改变;同一视网膜中,上方及后极部杂交信号的减弱较下方和周边部更为明显。 结论:视紫红质基因mRNA表达水平降低可能为光化学性视网膜损伤的早期信号。 (中华眼底病杂志,1997,13:228-230)  相似文献   
83.
84.
Autotransplantation presently constitutes the best option for the surgical treatment of non-palpable retained intra-abdominal testes. Silber first proposed this technique in 1978; it is not suitable in children under 3 years of age because of the small caliber of the testicular artery. In 1986 Dòmini, mindful of the problem of arterial vascularisation, carried out refluent testicular autotransplantation (RTAT), where a natural anastomosis between the testicular and deferential arteries is used. Venous drainage is guaranteed by performing a microsurgical anastomosis between the internal spermatic and inferior epigastric veins.At our institution this technique has been employed since 1990, replacing staged orchidopexy. We report a 2-year experience (1990–1992) in seven children who underwent RTAT and discuss the results obtained and the technique used.  相似文献   
85.
The direct-current electroretinogram of seven pigmented and seven albino rabbits was recorded from both eyes for almost 4 h in response to repeated identical light stimuli. Stimulus duration was 10 s, light intensity was 6.8 × 102 lux, and the interval between the beginning of succeeding light stimuli was 3 min. The dark-adaptation period preceding light stimulation was 30 min for one of the eyes (unoccluded eye) and 150 min for the contralateral eye (occluded eye), which was patched during the first part (117 min) of the experiment. In pigmented animals, the b- and c-wave amplitudes of the unoccluded eye slowly increased during the first part of the experiment but not significantly during the second. The a-wave amplitude was not significantly changed. After removal of the cover, the a- and b-wave amplitudes of the occluded eye immediately attained but did not exceed the level of those in the unoccluded eye, irrespective of the light adaptation induced by the stimulus flashes previously presented to the unoccluded eye. (Control experiments on six pigmented rabbits confirmed that stimuli identical to those used in the main part of the study caused a light adaptation, since a decrease in a- and b-wave amplitudes occurred after the first light stimulus following an initial dark-adaptation period of 2 h for both eyes.) In albino rabbits, electroretinogram responses were clearly discernible in the occluded eye also during the first part of the experiment, probably because of transillumination of the head. In other respects, the results were essentially similar to those of pigmented animals. The observation that occluded eyes did not dark adapt better, as judged by the electroretinogram responses, than contralateral eyes given repeated light adaptive stimuli may indicate the presence of a mechanism for transfer of adaptation information between the eyes.  相似文献   
86.
The effects of the stable cyclic adenosine monophosphate analogue adenosine 3, 5-cyclic monophosphorothioate Sp-isomer (Sp-cAMPS) on the direct-current electroretinogram and the standing potential of the eye were studied. Corneal recordings were obtained from unilaterally vitrectomized albino rabbit eyes during alternating intravitreal perfusions with Sp-cAMPS and a control solution (Pharmacia eye irrigating solution). The contralateral eye was used as a control. To evaluate further the effects on the c-wave,in vivo intraretinal microelectrode measurements were made during simultaneous intravitreal perfusion of Sp-cAMPS and irrigating solution, respectively. Sp-cAMPS in concentrations of 1, 10 and 100µM was tested by corneal direct-current electroretinography. There was no significant effect on the a-wave amplitude. The b-wave amplitude was reversibly elevated at an Sp-cAMPS concentration of 100µM (p<0.01, n=7). The c-wave amplitude was reversibly elevated at a concentration of 10µM (p<0.001, n=8), and this effect was more pronounced at 100µM (p<0.001, n=7). The SP increased reversibly at a concentration of 100µM (p<0.001, n=7). Microelectrode recordings were performed with Sp-cAMPS at a concentration of 100µM. The recordings showed significant increases in both the transepithelial potential (p<0.01, n=3) and the slow PIII (p<0.01, n=3). The effects of Sp-cAMPS on the b-wave as well as on the two components of the c-wave suggest influences on both the inner retina and the retinal pigment epithelium of the rabbit eye.Abbreviations PHS Pharmacia eye irrigating solution - AMP adenosine monophosphate - Sp-cAMPS adenosine 3, 5 - cyclic monophosphorothioate Sp-isomer  相似文献   
87.
The present study was conducted to assess the feasibility of laser Doppler velocimetry in young infants, as a prelude to ultimately undertaking such measurements in premature infants. A portable, unidirectional laser Doppler velocimeter was developed based on a Kowa RC-2 hand-held fundus camera. Six infants between 1 and 21 weeks of age were studied. Relative red blood cell velocity (fmax) at the centre of retinal arteries was measured over approximately 10 heart cycles. A pulsatility parameter (P=1–fmax.dia/fmax.sys), a summary index of vascular status, was determined from the average diastolic and systolic values of fmax. Velocity waveforms were obtained in four of the six infants. Arterial pulsatility for the group was 0.63±0.13. Precise non-invasive measurement of arterial red blood cell velocity waveforms in young infants was achieved. The high signal-to-noise ratio and temporal resolution of this data suggest that relative measurements of retinal blood flow may permit assessment of haemodynamic changes in premature infants.  相似文献   
88.
获得纯化的由大肠杆菌表达的小鼠 Fas配体(Fas ligand,FasL)。方法:以质粒 pET-15b为载体,在大肠杆菌BL21(DE3)中表达小鼠的FasL,用金属螫合亲和层析法纯化。结果:转化菌中,重组质粒是稳定的,异丙基-β-D硫代半乳糖苷可诱导小鼠FasL的表达 ,金属螫合亲和层析法可以初步纯化此蛋白。结论:在大肠杆菌中表达出小鼠的FasL,并得到初步纯化。  相似文献   
89.
Chen G  You Y  Zhang H 《中华眼科杂志》1999,35(4):305-308
目的 观察原发性开角型青光眼图形视网膜电图的改变及其特点,了解PERG在检测POAGPY视网膜功能方面的意义。方法 对36例(59只眼)POAG及32例(59只眼)年龄相匹配的正常人进行PEBG检测。结果 POAG患者PERG的AP1、AN2、AN1、AN2/AP1下降;运用AN2+AP1〈2.7及AN2/AP1下降;运用AN2+AP1〈2.7及AN2/AP1〈0.7的方法,对已确认的POAG进行  相似文献   
90.
视网膜脱离巩膜环扎术后眼前节结构的初步观察   总被引:4,自引:0,他引:4  
Wei W  Yang W  Chen Z  Zhu X  Wang J 《中华眼科杂志》1999,35(4):309-311,I017
目的 观察巩膜环扎术后眼前节结构的变化,探讨术后继发性闭角型青光眼的发病机制。方法 应用超声生物显微镜检查30例(33只眼)孔源视网膜脱离患者术前、后3-7天的活体奶前节形态结构,并分别进行定量测定,检查结果经统计学分析两组间配对tswcw,以P〈0.05作为差异有显著性标准。结果 术前1只眼存在裂隙样睫状体脱离。术后11只眼(33.3%)发生睫状体脱离,睫状体增厚水肿;术前睫状体厚度为(821.  相似文献   
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