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71.
72.
[背景 ]观察枪弹及弹壳伤对眼部损害程度及治疗手段 .[病例报告 ]本组 36例 40眼枪弹伤中(有 5例 5眼为弹壳伤 ) ,火枪、猎枪的铁砂弹及弹壳伤 2 1例 2 5眼 (6 0 % ) ,气枪子弹铅弹伤 10例 10眼(2 7% ) ,玩具枪塑料弹伤 5例 5眼 (13% ) .选择手术治疗 2 5例 2 9眼 (6 9% ) ,药物治疗 11例 11眼(31% ) .治疗结果视力提高 0 1以上为 10例 ,总有效率为 2 7% .[讨论 ]枪弹伤严重损害眼部 ,双眼致盲2例 4眼 ,单眼致盲 14例 14眼 (包括摘除眼球 4例 4眼 ) . 相似文献
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74.
反义PCNA与反义bcl-2脱氧寡核苷酸抑制人视网膜色素上皮生长 总被引:4,自引:1,他引:3
目的 观察反义增生细胞核抗原 (PCNA)和反义 bcl-2脱氧寡核苷酸对培养的人视网膜色素上皮细胞 (RPE)生长的作用 .方法 用 DNA合成仪合成有 1 8个核苷酸的反义PCNA和 1 5个核苷酸的反义 bcl- 2脱氧寡核苷酸片段 ,以不同浓度加入 RPE培养液 ,培养 2~ 4d,用 SABC法检测细胞PCNA和 bcl- 2的表达 ,用 MTT法及流式细胞仪测定细胞抑制率 .结果 6 .2 5~ 1 0 0μm ol· L- 1 的反义 PCNA对 RPE的抑制率为 8.3%~ 38.4% ,呈剂量依赖性 ,并抑制细胞 PCNA的表达 .反义 bcl- 2未显示抑制作用 .结论 反义 PCNA脱氧寡核苷酸可抑制近 40 %的 RPE生长 ,其临床应用值得进一步研究 相似文献
75.
The effects of a prolonged cognitive task prior to sleep onset on subsequent sleep patterns were examined in 14 healthy subjects who were randomly assigned to two conditions. Those assigned to a working condition were asked to engage in a prolonged cognitive task until close to bedtime (0200 hours), whereas those assigned to a relaxing condition were instructed to perform the same task during the daytime and then to stay awake in a relaxed state until the same bedtime as the work group. Visual scoring of sleep stages showed no significant differences in the amounts of stage 4 and slow wave sleep (stage 3+4) between the two conditions. Power spectrum analysis of sleep electroencephalogram (EEG) revealed that the EEG (0.5–4.0 Hz) power density in the first non-rapid eye movement (REM)-REM sleep cycle was significantly lower following the prolonged cognitive task prior to sleep onset than following the relaxed wakefulness and that the decreased EEG power density in the first sleep cycle was not compensated for during the later part of the sleep. These findings would indicate that the prolonged cognitive task prior to sleep onset may suppress EEG power density during subsequent sleep, suggesting that such a task may interfere with the development of deep non-REM sleep. 相似文献
76.
S. J. Rosansky MD R. Rhinehart MD D. Whittman MPH S. J. Menachery 《Clinical autonomic research》1995,5(3):151-154
In published studies of chronic haemodialysis patients, the frequency of autonomic dysfunction varies widely. One reason for the variation may be the time of testing with respect to time of dialysis. The current study tests the hypothesis that autonomic function — as measured by heart rate responses to the Valsalva manoeuvre (Valsalva ratio) and 30:15 electrocardiogram (ECG) R—R interval to upright posture (postural ratio) — is different when patients are above dry weight (predialysis) than when they are at or below dry weight (postdialysis). The study also reviews available literature to analyze other factors that may affect the results of autonomic testing in this population. A total of 25 chronic haemodialysis patients underwent standard Valsalva and 30:15 R—R interval postural autonomic testing prior to and after haemodialysis. In addition, pre- and postdialysis orthostatic responses were measured and compared with a control population. The 30:15 ratio increased after dialysis (p = 0.001). The Valsalva ratio did not change with dialysis. Out of 25 subjects, seven had an abnormal 30:15 ratio prior to dialysis decreasing to two out of 25 patients postdialysis (p < 0.03). Orthostatic responses predialysis did not differ from those in the control group. Review of the literature shows great variability in definition of normal Valsalva and postural (30:15 R—R interval) ratios. Diabetic patients in the current and prior studies were more likely to have abnormal responses. In conclusion, the prevalence of autonomic dysfunction in chronic dialysis patients as determined by Valsalva and 30:15 ECG postural ratios may be influenced by the following factors: when subjects are studied with respect to their dialysis treatment; the number of subjects with diabetes; and the cut-off point used to define abnormal test results. Abnormal Valsalva ratios are less frequent when measured postdialysis. 相似文献
77.
15kg负重沙漠干热应激行军速度和时间对人体GSH和SOD的影响 总被引:1,自引:0,他引:1
目的 探讨沙漠干热负重应激行军人体GSH 和SOD 作用机制。方法 对74 名15 kg 负重在沙漠干热环境以不同速度和时间行军战士和对照人群血浆的变化进行了研究。结果 15 kg 负重,3-5km/h 和5 km/h 行军者GSH 在应激的最初1 小时内迅速上升,约1 小时达到高峰,之后迅速下降;随着行军速度的增加,机体抗氧化作用所消耗的SOD 量增加,血浆SOD 浓度亦随之下降。结论 从行军时间来看,在应激的最初1 小时内,因应激诱导的GSH 的合成和SOD 的量增加,故沙漠干热环境负荷应激行军以15 kg、3-5 km/h 为宜。 相似文献
78.
A new approach to the study of ocular chromatic aberrations 总被引:2,自引:0,他引:2
We measured the ocular wavefront aberration at six different visible wavelengths (between 450 and 650 nm) in three subjects, using a spatially resolved refractometer. In this technique, the angular deviation of light rays entering the pupil at different locations is measured with respect to a target viewed through a centered pupil. Fits of the data at each wavelength to Zernike polynomials were used to estimate the change of defocus with wavelength (longitudinal chromatic aberration, LCA) and the wavelength-dependence of the ocular aberrations. Measured LCA was in good agreement with the literature. In most cases the wavefront aberration increased slightly with wavelength. The angular deviations from the reference stimulus measured using a magenta filter allowed us to estimate the achromatic axis and both optical and perceived transverse chromatic aberration (TCA), (including the effect of aberrations and Stiles-Crawford effect). The amount of TCA varied markedly across subjects, and between eyes of the same subject. Finally, we used the results from these experiments to compute the image quality of the eye in polychromatic light. 相似文献
79.
人眼眩光失能测定及其临床意义 总被引:1,自引:0,他引:1
目的:观察国产仪器测定眩光失能的性能与规律,并讨论其临床意义。方法:采用MGT—1多功能视觉眩光测试仪(海军医学研究所研制),按规定方法操作。测定正常人30名56眼(矫正视力全部≥1.0,晶体透明,无其他明显眼病),晶体混浊患者15人27眼。测定目标亮度及眩光亮度设置为中—中及弱—中两档分别模拟白天及夜间眩光失能。结果:中—中状态下,眩光失能值正常人均值为9.22%(全距0~31),低于晶体混浊者(24.05%,全距9~67),两者差异显著。正常眼在弱—中状态眩光失能值较中—中状态明显(均值20.12%,全距0~56)。不同频率条件对正常及晶体混浊眼眩光失能的影响不同,低频及中频较高频区的影响明显。结论:作为视功能评论指标,眩光失能检查是一种实用方法。在眼科临床及人体工效学上具有重要的意义。 相似文献
80.
L. E. Pablo M. L. Gómez M. Pueyo T. Ramírez C. Torrón B. Melcón O. Ruiz F. M. Honrubia 《International ophthalmology》1996,20(1-3):11-14
Both filtering surgery with Mitomycin-C and diode laser cyclophotocoagulation have proved to be effective alternatives in cases of glaucoma with poor surgical prognosis. The right eyes of 40 pigmented rabbits were randomly divided into 2 groups: Mitomycin-C group underwent filtering surgery with application of 0.4 mg/ml of Mitomycin-C whereas the diode laser (DL) group received 15 applications of 1.8 J (1800 mW. 1000 ms) distributed in 270°. Mean IOP showed statistical differences in two periods between days 3–13 and 45–60 — Mann-Whitney U test — with a higher IOP lowering in the DL group. The comparison of IOP survival curves (Log-Rank test) was not significant p = 0.070809. Ocular hypertension, hyphema and inflammatory signs were higher in the DL group, both in short and long term, but in terms of statistical significance only ocular hypertension showed differences p = 0.00011717 - Fisher exact test. Microscopic examination revealed patent sclerostomies in 60% of the MMC group eyes with different grades of fibroblastic proliferation. In the DL group we observed necrosis of the sclieral stroma and of the pigmented and unpigmented ciliary epithelium, with signs of thermal coagulation of the ciliary stroma and of the stromal vasculature. We must point out that the treatment with laser has proved to be more effective although both treatments showed very acceptable IOP lowering until 2 months after the surgery. 相似文献