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51.
1993年7月~1998年1月为103例(106只眼)难治性青光眼患者施行国产房水引流物(HAD)置入术。术后平均随访328月。术后1年时平均眼压22±1.4kPa。术后1~5年的手术成功率分别为838%,804%,771%,710%及643%。术中联合应用丝裂霉素C的病例,其术后1年时的成功率为895%。术后常见的并发症有持续性浅前房,局限性脉络膜脱离及眼压升高等。认为HAD可用于治疗难治性青光眼。  相似文献   
52.
Inflammation-induced changes in peripheral glutamate receptor populations   总被引:5,自引:0,他引:5  
The ionotropic glutamate receptors N-methyl-d-aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and kainate (KA) have been localized on subpopulations of unmyelinated and myelinated sensory axons in normal skin. Behavioral studies indicate that activation of these receptors results in nociceptive behaviors and contributes to inflammatory pain. The goal of the present study was to determine if these glutamate receptors might contribute to the peripheral hypersensitivity observed in inflammation. The major findings were that 48 h following complete Freund's adjuvant (CFA)-induced inflammation, the proportions of unmyelinated axons labeled for NMDA, AMPA or KA receptors were 61%, 43% and 48%, respectively, in cutaneous nerves in the inflamed paw compared to 48%, 22% and 27%, respectively, in the non-inflamed paw. The proportions of myelinated axons labeled for NMDA, AMPA or KA receptors were 61%, 61% and 43%, respectively, compared to 43%, 42% and 28%, respectively, in the non-inflamed hindpaw. These increases were all significant. These data indicate that the number of sensory axons containing ionotropic glutamate receptors increases during inflammation, and this may be a contributing factor to peripheral sensitization in inflammation.  相似文献   
53.
The effects of changes in temperature on primary and secondary endings of isolated cat muscle spindles were investigated under ramp-and-hold stretches and different degrees of pre-stretch. Temperature-induced alterations of the discharge frequency were compared over a temperature range of 25–35°C. Both primary and secondary endings responded to warming with increasing discharge frequencies when the spindle was pre-stretched by 5–10% of its in situ length. The following differences between the temperature effects on primary and secondary endings were observed: (1) The temperature coefficients (Q10) obtained from the discharge frequencies during the dynamic and static phase of a stretch were similar for endings of the same type, but they were larger in primary endings (range of Q10: 2.3–3.3; mean: 2.9) than in secondary endings (range of Q10: 1.6–2.2; mean: 2.0); (2) With primary endings, but not with secondary endings, the temperature sensitivity (imp s−1 °C−1) was larger during the dynamic phase than during the static phase of a stretch; (3) In primary endings, the fast and slow adaptive components occurring in the discharge frequency during the static phase of a stretch clearly increased with warming while in secondary endings, the slow decay was less affected, and the fast decay showed no change; (4) In relaxed spindles, the excitatory effect of warming was overlaid by a strong inhibitory effect as soon as the temperature exceeded about 30°C, resulting in an abrupt cessation of the background activity in most secondary endings, but not usually in primary endings. In general, warming induced an enhanced stretch sensitivity in both types of ending, and additionally an inhibitory effect that is obvious only in secondary endings of relaxed spindles. The different effects of temperature on the discharge frequency of primary and secondary afferents are assumed to be caused by different properties of their sensory membranes.  相似文献   
54.
Background: Because calcium channel blockers reduce vascularresistance, they may have a clinical application in the treatment ofnormal-tension glaucoma (NTG). This study investigates changes inboth the optic disc blood flow and the hemodynamics of retrobulbarvessels in NTG patients after the systemic administration of a calcium channel blocker. Methods: Twelve eyes of 12 NTG patients (meanage 57 6 ± 15.3 years) were examined before and after a 4-weektreatment with 2 mg b.i.d. oral nilvadipine, an L-typc calcium channel blocker. By scanning laser-Doppler flowmetry (SLDF), we obtained the velocity, flow, and volume from within a 10 × 10 pixel windowplaced on the temporal rim region of the optic disc perfusion map. Byultrasound color Doppler imaging (CDI), we measured the peak systolicvelocity (PSV) and the end diastolic velocity (EDV) of the ophthalmicartery (OA), central retinal artery (CRA), nasal posterior ciliary artery (NPCA), and temporal posterior ciliary artery (TPCA). We then calculated a resistance index (RI) for each vessel. Results: After treatment, the flow and velocity of the optic disc blood flow significantly increased (P < 0.05).Nilvadipine also significantly reduced RIs of the CRA, NPCA, and TPCA(P <0 .05), and increased both the PSV of the NPCA and the EDVs of the CRA, NPCA, and TPCA. The percent change in velocity correlated significantly with the percent changes of the CRA RI and NPCA RI. Conclusions: Oral nilvadipine appears to reduce orbital vascular resistance, which consequentlyincreases the optic disc blood flow. Abbreviations.BP – blood pressure;CRA – central retinal artery;CDI – ultrasound color Doppler imaging;EDV – end diastolic velocity;NPCA – short posterior ciliary arteries located nasal to optic nerve;NTG – normal-tension glaucoma;OA – ophthalmic artery;PP – perfusion pressure;PSV – peak systolic velocity;RI – resistance index;SLDF scanning laser-Doppler flowmetry;TPCA – short posterior ciliary arteries locatedtemporal to optic nerve.  相似文献   
55.
硅油继发青光眼的发病相关因素及治疗的初步探讨   总被引:7,自引:0,他引:7  
梁勇  黎晓新 《眼科研究》1999,17(5):382-384
探讨硅油继发青光眼的发病相关因素及治疗。方法对行玻璃体切割,硅油注入术的275例患者术后随访结果进行回顾性研究。结果硅油继发青光眼的发病率为11.3%,随着硅油在眼内存留时间的延长,其发病率增高。  相似文献   
56.
Dawei  Peng  Shujun  Zeng 《眼科学报》1999,15(1):51-55
Purpose: To observe the inhibitory action of homoharringtonine liposome during the healing process of wounds in the filtering sitesMethods: posterior sclerectomies were performed in 14 rabbits. Postoperatively one eye of each rabbit received subconjunctival injections of HH liposome and fellow eye received saline injection in a randomized masked fashion.Results; Fourteen days after operation the IOP of experimental eyes reduced significantly (P < 0.01) as compared with the controlled eyes, and the number of remaining filtering blebs increased noticeably (P< 0.05). Pathohistological examination revealed that the number of fibroblasts per square micron in the filtering sites and the thickness of the scars in the center of the filtering sites of the experimental eyes were less than those of the controlled eyes. No serious ocular toxic and side effects were found.Conclusion : This experiment suggests that homoharringtonine liposome can markedly inhibit the scar formation of filtering sites after glaucoma fi  相似文献   
57.
目的探讨抗心磷脂抗体(ACA)与青光眼疾患的临床相关意义。方法对26例青光眼患者及11例非青光眼患者,采用抗心磷脂抗体酶免疫(ELISA)测定法,进行抗心磷脂抗体检测。结果青光眼组IgGACA与IgMACA值均比对照组高,有显著差异(P<0.05);其中开角型青光眼IgGACA与对照组之IgGACA值比较无显著差异(P>0.05);开角型青光眼IgMACA与对照组之IgMACA值比较有显著差异(P<0.05)。闭角型青光眼与对照组比较:IgGACA与IgM之ACA值比较均有显著差异(P<0.05)。结论青光眼病人的抗心磷脂抗体较高,预测可能产生视网膜静脉阻塞,需进一步追踪随访  相似文献   
58.
目的评价睫状体冷冻术联合巩膜穿刺术在治疗绝对期青光眼中的应用。方法对绝对期青光眼47眼施行睫状体冷冻术联合巩膜穿刺术,观察术后3a内眼压变化。结果全部病例术后高眼压症都获缓解,对术后早期眼压反弹,本术较单纯施行睫状体冷冻术者控制眼压疗效好(P<0.01),且无副作用和并发症。结论睫状体冷冻术联合巩膜穿刺术是治疗绝对期青光眼更简便、安全、有效的手术选择。  相似文献   
59.
探讨发生于无晶体眼和人工晶体眼的青光眼的有效的手术治疗方法。方法:回顾分析1992年11月~1997年6月我院45例45眼发生于无晶体眼和人工晶体眼的青光眼的住院病例的临床资料。手术方法包括小梁切除术、睫状体冷冻术、青光眼减压阀植入引流术以及其他手术。结果:青光眼减压阀植入引流术控制眼内压优于睫状体冷冻术和小梁切除术,术后合并使用降眼压药物少于睫状体冷冻术后。结论:发生于无晶体眼和人工晶体眼的青光眼的治疗需根据临床情况考虑,青光眼减压阀植入引流术有较好的疗效  相似文献   
60.
目的 :评价青光眼减压阀植入术治疗无晶体眼和人工晶体眼青光眼的疗效 ,探讨术后并发症和预防措施。方法 :回顾性分析19例 ( 2 0眼 )无晶体眼和人工晶体眼青光眼患者行青光眼减压阀植入术。其中 13眼行 Ahmed减压阀植入 ,7眼行 Krupin减压阀。结果 :术后一周平均眼压 1.93± 0 .69k Pa,95 %术眼眼压控制正常。平均随访 18.9± 6.9月的 14只术眼平均眼压 2 .4 0± 0 .4 7k Pa,64 .3 %术眼眼压控制正常。术后常见并发症有前房导管口阻塞、导管接触角膜、前房积血、低眼压等。结论 :青光眼减压阀植入术是治疗无晶体眼和人工晶体眼青光眼的较为有效的方法 ,但仍存在一定的并发症  相似文献   
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