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51.
目的 建立高效液相色谱法测定蜂丁麻滴眼剂中盐酸麻黄碱含量的方法。 方法 采用YWGC18分析色谱柱 ( 4 6mmID× 2 5 0mm ,粒径 10 μm) ,C18保护柱 ( 4 6mmID× 5mm ,粒径 10 μm) ,流动相 10 %乙腈 ( 0 5 %三乙胺 ,磷酸调pH3 0 ) ,流速 1 0ml/min ,检测波长 2 0 8nm ,测定对照品和样品色谱图 ,记录盐酸麻黄碱色谱峰面积 ,计算其含量。 结果 盐酸麻黄碱的理论板数为 10 0 0 0。回归方程 :y =90 5 878 16 15 1738x ,r=0 9999,线性范围 0 4 0 32~ 1 6 13μg。平均回收率为 99 2 % (RSD1 6 % )。 结论 该法操作简便 ,结果准确 ,可用于测定蜂丁麻滴眼剂中盐酸麻黄碱的含量 相似文献
52.
The disaccharide trehalose is a key element involved in anhydrobiosis (the capability of surviving almost complete dehydration) in many organisms. Its presence also confers resistance to desiccation and high osmolarity in bacterial and human cells by protecting proteins and membranes from denaturation. The present study used a novel murine dry eye model induced by controlled low-humidity air velocity to determine whether topically applied trehalose could heal ocular surface epithelial disorders caused by ocular surface desiccation. In addition, the efficacy of 87.6 mM trehalose eyedrops was compared with that of 20% serum, the efficacy of which has been well documented. Mice ocular surface epithelial disorders were induced by exposure of murine eyes to continuous controlled low-humidity air velocity in an intelligently controlled environmental system (ICES) for 21 days, which accelerated the tear evaporation. The mice were then randomized into three groups: the control group received PBS (0.01M) treatment; a second group received 87.6 mM trehalose eyedrops treatment; and the third group received mice serum eyedrops treatment. Each treatment was administered as a 10 μl dose every 6 h for 14 days. The resultant changes in corneal barrier function and histopathologic examination of cornea and conjunctiva were analyzed and the level of apoptosis on the ocular surface was assessed using active caspase-3. After 14 days of treatment, the corneal fluorescein staining area, the ruffling and desquamating cells on the apical corneal epithelium, as well as the apoptotic cells on ocular surface epithelium had significantly reduced in eyes treated with trehalose compared with those treated with serum and PBS. In contrast, after 14 days of treatment, improvements in the thickness of the corneal epithelium, the squamous metaplasia in conjunctival epithelium and the number of goblet cells of the conjunctiva were less marked in eyes treated with trehalose compared with serum. These results demonstrated that trehalose could improve the appearance of ocular surface epithelial disorders due to desiccation through suppression of apoptosis. Trehalose produces some of the same responses as serum upon topical application and can maintain corneal health. 相似文献
53.
R. Jiménez M. D. González M. A. Pérez J. A. García 《Ophthalmic & physiological optics》2003,23(2):97-107
The evolution of the accommodative function and development of ocular movement are evaluated in a non-clinical paediatric population (1056 subjects) aged 6-12 years, providing means for each age in the optometric tests that evaluate the accommodative amplitude, accommodative facility, accommodative response (lag), and saccadic movements. A comparison of these values between ages (anova) established three distinct trends in the behaviour of these parameters. The accommodative amplitude, measured by modified dynamic retinoscopy, and the evaluation of the saccadic movements by the development of ocular movements [developmental eye movement (DEM)] test showed continuous change with age. The values for monocular and binocular accommodative facility, measured by +/-2.00 D flippers, indicated the need to divide the population into two age groups (6-7 and 8-12 years). Finally, the means of accommodative response, measured by monocular estimation model (MEM) retinoscopy, and the direct observation of saccadic movement revealed no significant differences between ages, establishing a single mean reference value for the age group studied. 相似文献
54.
高度近视LASIK治疗中角膜瓣厚度的探讨 总被引:8,自引:0,他引:8
目的:探讨高度近视LASIK治疗中角膜瓣厚度问题。方法:142例(283眼)屈光度-9.00~-12.00 D的近视患者用日本NIDEK MK-2000全自动微型板层角膜切割刀切开角膜瓣,厚度71~184μm,激光切削方式一致。将角膜瓣厚度≤110μm分为Ⅰ组,72例(144眼);角膜瓣厚度>110μm分为Ⅱ组,70例(139眼)。对术前、术后屈光度、视力以 及剩余角膜基质床厚度进行比较。结果:术前平均角膜厚度:Ⅰ组为(531.76±30.28)μm(469~575μm),Ⅱ组为(550.66±24.45)μm(506~584μm),两者有明显差异(P<0.05)。术后剩余角膜基质床厚度:Ⅰ组为(333.01±3.30)μm(273~452μm),Ⅱ组为(309.71±31.41)μm(254~368μm),两者有明显差异(P<0.05)。术前屈光度两组分别为(-10.61±1.01)D及(-10.13±0.73)D,两组间无明显差异(P>0.05),术后7 d时分别为(+1.05±1.38)D及(+1.32±1.70)D,两组间也无明显差异(P>0.05),而术后3m Ⅰ组为(-0.13±0.94)D,Ⅱ组为(-1.06±0.96)D,两组有明显的差异(P<0.01)。术前、术后不论UCVA还是BCVA,两组无明显差异(P>0.05)。结论:治疗高度近视时70~110μm的角膜瓣的制作是合理的,并不影响术后视力,对防止术后屈光回退是有效的,对一个有经验的医生来说是可以很好完成的。 相似文献
55.
干眼和眼表疾病为眼科最常见疾病。本文报告包括干眼症在内的各种眼表疾病68例100眼,应用正大维他和维伦滴眼液治疗,获得良好的疗效。在这些滴眼液内含有玻璃酸钠粘多糖类粘性增强剂,可延长药液在角膜前表面的仪时间和增强药效。在治疗中未出现任何副作用。 相似文献
56.
实验性视网膜脱离Na十-K+-转运ATP酶活性及RPE超微结构改变 总被引:2,自引:1,他引:1
目的:探讨实验性视网膜脱离(retinal detachment,RD)后视网膜色素上皮(retinal pigment epithelium,RPE)对视网膜下液(subretinal fluid,SRF)的输导功能。
方法:将制作成功的实验性单眼RD 28只家兔随机分为4组,每组7只,每只兔的另眼作为对照。分别取RD部位的RPE-脉络膜组织和对照眼相应部位的组织匀浆,再测定ATP水解产物无机磷含量,以判断ATP酶活性;并作实验和对照眼的两种组织相应部位的RP正电镜观察。
结果:实验眼Na十-K+-转运ATP酶活性为(2.16士1.26)/μmol(mg·h),对照眼为(4.84±1.59)μmol/(mg·h),二者差异显著(t=5.52,P<0.01);酶活性降低程度随病程延长而减轻(p<0.05)。电镜观察实验眼RD后第2至4周有自脉络膜向视网膜方向的吞饮泡,且随病程延长而增多。
结论;RD发生后RPE的外向输导功能增强,随病程进展,此功能减弱而内向输导功能产生。
(中华眼底病杂志,1997,13:83-85) 相似文献
57.
Charlotte A. Hazel 《Clinical & experimental optometry》1995,78(3):98-105
For years it has been recognised that many sports place demands on vision and particular visual skills. There is much evidence to show that the correction of visual dysfunction such as ametropia and binocular and accommodative anomalies results in improved sporting performance for those sports. More controversial and of special interest is the suggestion that it is possible to train visual abilities of subjects who do not present with traditionally recognised functional disorders of vision. It has been proposed that sporting performance can be improved as a result of this training. However, this review found the evidence to be inconclusive. In addition, there are studies that suggest athletes have better visual abilities than non-athletes and good athletes have better abilities than less skilled athletes. However, it has not been determined whether these superior abilities are innate to the athlete or have developed through practice. A review of the available literature was unable to prove (or disprove) either of these proposals. However, there appears to be enough evidence to warrant further investigation of these questions, in order that the area of sports vision and vision training can be more fully understood. This will enable clinicians to take full advantage of the potential of sports vision practice to assist athletes. (Clin Exp Optom 1995; 78: 3: 98–105) 相似文献
58.
Currently, there is debate in the clinical literature as to whether defects in vertical gaze are a consequence of normal ageing or a component of an underlying neurodegenerative disorder. Although pathological changes have been demonstrated in diseased subjects, no study to date has addressed the question of normal ageing effects. In this retrospective study, we examined 23 neurologically and pathologically normal subjects (age 18-91). Using an unbiased, frame-based sampling method, we quantified neuronal and glial cell densities in 10 young (<50) and 13 aged (>65) subjects in the rostral interstitial nucleus of the medial longitudinal fasciculus (riMLF), the key premotor substrate in the vertical gaze pathway. We found no statistically significant difference in neuronal density, glial cell density, or neuron-to-glial cell ratios between the young and the aged. We conclude, therefore, that neuronal loss, neuronal atrophy, or gliosis in the riMLF are not consequences of normal ageing. 相似文献
59.
At about the time of eye opening, one eye of seven tammar wallaby pouch young was surgically rotated about the optic axis by approximately 90°. In adulthood the projection of the visual field through the rotated eye onto the contralateral superior colliculus was mapped electrophysiologically. Although apparently distorted, the projection could be coherently rerotated mathematically to a reasonable copy of the normal projection from the opposite eye of the same animal, including details such as regional variations of the magnification factor. The same was true of three adult animals in which the eye rotation was done after anaesthesia immediately before the electrophysiological mapping. In animals in which the visual field seen through one eye, the other being normal, was rotated for the entire period of visual experience, there was no sign of compensation or rearrangement of the topographic map. Retinocollicular synaptic connections appear unmoved by such discordant visual experience. 相似文献
60.
Sverker Norrby 《Ophthalmic & physiological optics》2005,25(2):153-161
Dubbelman and co-workers have determined intraocular spacings and surface shapes in living eyes by means of corrected Scheimpflug images in a large number of subjects of different age at several levels of accommodation. They give relationships for key anterior segment parameters as a function of age and level of accommodation. These are used in this paper to build a schematic eye incorporating aspheric surfaces. This eye model is analysed by means of ray tracing with a technique developed for use with a common spreadsheet computer program. The Dubbelman eye model appears to be well corrected for spherical aberration. Compared with measurements on real eyes it agrees well in general, but spherical aberration is negative, while in real eyes it tends to be positive. 相似文献