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51.
探刊干性型老年黄斑变性(age-related macular deganeration,AMD)的病变发展特征并 寻找监测AMD病情进展的较敏感指标。
方法:用眼底彩色照相和眼底荧光血管造影(FFA)、明视视网膜电囤(ERG)、FM100-hue 色彩试验及视力检查,对60例(111眼)50~80岁、视力≤1.0的干性型AMD患者进行3~74个月(平均30.2个月)的随访观察。
结果:本组68眼经FFA检查、平均25.6个月随访,其中25%的患眼病灶损害有快慢不一的发展.全部111眼视力在平均30.2个月随访中有18%患眼的视力下降2行以下,且与病灶进展相符,FM100-hue 色彩试验的被随访者中,随访2年以后,其总错误分明显的增加(P<0.01).63眼的明视ERG在随访过程中无明显变化。
结论:大部分干性AMD患眼的病灶损害和视力可以在较长时间内维持稳定。FM100—hue的总错误分可能为监测AMD病情进展的较敏感指标.
(中华眼底病杂志,1997,13:150-152) 相似文献
52.
L Z Wu L H Zeng Q Y Ma Y J Xie Y Z Chen D Z Wu 《Japanese journal of ophthalmology》1988,32(2):236-245
The hereditary characteristics of enzyme deficiency and dermatoglyphics in congenital color blindness (CCB) were studied. We propose that there is a linkage between the two loci on the X-chromosome determining CCB and glucose-6-phosphate dehydrogenase (G6PD), based on our study of a high incidence of G6PD deficiency in 156 male cases with CCB. The CCB gene is closely linked with that of G6PD deficiency from our pedigree investigations. The rise in the frequency of eight or more whorls, the low value of atd angle and the presenting rate of real palmar patterns of the thenar, hypothenar and I, areas presented the hereditary traits of congenital color blindness. 相似文献
53.
The electrophysiological effects of dicentrine on the conduction system of rabbit heart. 总被引:3,自引:2,他引:1 下载免费PDF全文
1. The electrophysiological effects of dicentrine, an aporphine alkaloid isolated from the root of Lindera megaphylla, were examined in the Langendorff perfused rabbit heart and rabbit isolated cardiac cells. 2. Standard electrophysiological characters were measured in the Langendorff perfused rabbit heart (control study) and after 5 min exposure to 1, 3 and 9 microM of dicentrine and during the subsequent recovery phase sequentially (n = 7). The same study protocols were performed in 0.5 to 4.5 microM quinidine (n = 7), 18 to 162 microM procainamide and N-acetylprocainamide (n = 7) for comparison. 3. The results showed that the spontaneously beating heart rate and the sinoatrial (SA) and atrioventricular nodal (AH) conduction time were not significantly affected by dicentrine but were significantly suppressed by the higher doses of quinidine (4.5 microM) and procainamide (162 microM). 4. The His-Purkinje conduction time was significantly increased by the higher dose of dicentrine, quinidine and procainamide. 5. The ventricular repolarization time and its effective refractory period were significantly increased by the higher dose of dicentrine and the other agents. 6. The effective refractory period of the atrium, AV node and His-Purkinje system were also significantly increased by dicentrine and the other agents. 7. A voltage clamp study revealed that the prolongation of atrial action potential duration by dicentrine (9 microM) was associated with a significant inhibition of the transient potassium outward current. As well as inhibition of the transient outward current, a significant inhibition of the sodium inward current by dicentrine was found.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
54.
蛭弧菌与微生物污染的相互关系探讨 总被引:1,自引:0,他引:1
本文在实验室条件下动态观察了蛭弧菌含量与微生物污染的相互关系。结果表明:蛭弧菌含量的增加滞后于水体污染,而污染过后蛭弧菌则可在较长时间内维持较高水平,这一特性在水污染指示中的可能作用值得进一步探讨。 相似文献
55.
复治矽肺结核化疗效果观察 总被引:3,自引:0,他引:3
我们自1980~1988年对79例复治矽肺结核进行化疗。其中绝大多数为慢性纤维化空洞性病例,均经细菌学证实,并由尘肺诊断组认定为矽肺合并结核。本组病例分别以KM、INH、RFP、PZA,或SM、INH、RFP、EB联合,分两阶段治疗18个月,获痰菌阴转79.2%,其中KHRZ与SHRE组分别为93.9%与68.2%(P<0.05)。自疗程结束追踪2~8年,其细菌复阳率分别为6.45%和10.0%(P>0.1)。并对影响其过去治疗失败的原因及对策进行了讨论。 相似文献
56.
本文报道老年非何杰金氏淋巴瘤(NHL)59例并与同期非老年患者138例相比。老年患者占同期NHL总数的29.9%。59例中有结内型43例,结外型16例;低度恶性与中度恶性各12例,高度恶性35例。与非老年组比较,老年组的就诊原因、病变部位、恶性程度、细胞类型和预后等方面无何差别,提示年龄对上述特征无明显影响。 相似文献
57.
58.
Minzhong Yu Lezheng Wu Dezheng Wu 《Documenta ophthalmologica. Advances in ophthalmology》1990,76(1):37-46
The visual pursuit test is a method that collects and analyzes the characteristics of pursuit eye movements and examines the function of the eye movement system. This paper analyzes the model parameters of the smooth pursuit eye movement system in order to explore a method for improving the analysis. The input-output relationship of the smooth pursuit system can be expressed by a quasilinear model. We compute the model parameters (gain, phase, spectral purity, cross covariance) by digital signal processing. Eye movement is recorded by electrooculogram. Both eyes are tested individually. The visual target moves at frequencies of 0.2, 0.4, 0.8, 1.2, and 1.6 Hz. Ranges are gain, 1.01 to 0.70; phase, -0.1 ° to -66 °; spectral purity, 0.97 to 0.70; and cross covariance, 0.99 to 0.26. We tested 40 normal subjects as well as patients with ataxia (8), vertigo (18), and ophthalmoplegia (9). The oculomotor system of normal subjects functions as a linear system in the performance of this test at 0.2 to 0.8 Hz. The spectral purity dropped to about 0.70 at 1.6 Hz. The variability of all measures increases greatly at 1.6 Hz, which indicates that this target motion exceeds the tracking ability of many normal subjects and that the oculomotor system of normal subjects functions as a nonlinear system in this condition. Statistical tests show no significant differences between sex, age, and the two eyes. The model parameters tentatively proved effective in clinical application. 相似文献
59.
本文在分析黑龙江省妇幼保健机构设置现状的基础上,论述了在社会主义市场经济新形势下,妇幼保健机构发展的指导思想、模式与对策。 相似文献
60.
At extreme altitude of 5,620 m, cardiac function was examined with electrical impedance at rest and during exercise. Mountaineers as subjects of experiment were divided into two groups: 15 subjects were Tibetan natives, and 10 subjects were Han visitors of expedition (both were young healthy males). The results showed that no significant difference was seen between the two groups in cardiac pump function at rest. In the Han visitors during exercise, HR increase was restricted, SV and CO were decreased, and PEP/LVET ratio was increased. In the Tibetan natives, HR increased gradually with increased work load, SV tended to be stable CO increased significantly under higher work load, and PEP/LVET ratio decreased gradually. These results suggest that the Tibetan natives were adapted to hypoxic environment much better than the immigrants because their cardiac reserve capacity and maximal oxygen uptake were better than the immigrants at extreme altitude. 相似文献