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81.
Purpose: To compare the short-term efficacy and side effects of betaxolol and timoloi in treatment of primary open angle glaucoma or ocular hypertension. Methods: Fourteen patients with newly diagnosed early primary open angle glaucoma or ocular hypertension were included.Each patient received 0.5% timoloi and 0.5% betaxolol twice daily for four weeks in two phases. Between two courses of treatment there was four weeks wash out period. At the end of study the effect of these two drugs on intraocular pressure, mean arterial blood pressure,pulse rate,basic tear secretion and ocular symptoms were evaluated and statistically analyzed,using wilcoxon and chi-squar test.RESULTS:The study was performed on fourteen patients with baseline IOP of 26.7 ±1.5 mmHg.After four weeks treatmem,timoiol and betax-olol reduced IOP by 7.8±1.2mmHg or 29% and 6.1±1.3mmHg or 23%, respectively (P<0.001). The difference between two groups was significant(P<0.001). Mean arterial blood pressure was reduced with betaxolol and tim  相似文献   
82.
BACKGROUND/AIMS: It has recently been proposed that the refractive index (RI) measured by means of optical coherence tomography (OCT) may be a valid measure for hydration of skin. In this pilot study, using OCT in vivo, we aimed to investigate the interday variability of RI measurements and acute changes of RI following the application of a moisturizer. METHODS: Twenty healthy Caucasian volunteers were investigated on their forearms using a commercially available OCT system (SkinDex 300, ISIS optronics GmbH, Mannheim, Germany) fitted with an integrated algorithm for the evaluation of the RI. The interday repeatability of the OCT method was determined performing symmetrical measurements on both forearms on day 1, 5, 9, and 13. In order to investigate the acute effect of a moisturizer on RI, OCT assessments were performed before and 10 min after the application of an aqueous lotion with a lipophilic phase. As a control, the contralateral site was investigated in the same way, except for the use of distilled water instead of the lotion. RESULTS: Assessments of interday variability revealed insignificant (P>0.05) variances between the four measurement times as expressed in very small repeatability coefficients (right arm: 0.039; left arm 0.053) and small coefficients of variance (right arm: 1.02%; left arm: 1.38%). With regard to the RIs measured over time, we could not observe significant (P>0.05) differences between the two symmetrical anatomic sites (mean+/-SD of RI: 1.3893+/-0.0142 (right arm); 1.3875+/-0.0192 (left arm)). The acute effect of the moisturizer was indicated by a significant decrease of the RI 5 min after the application of the lotion (1.399+/-0.01 vs. 1.387+/-0.02; difference between means: 0.012; P=0.033; 95% confidence interval: 0.001-0.0023). However the control site treated with distilled water did not show significant differences between the two measurement times (1.387+/-0.013 vs. 1.391+/-0.023; difference between means: -0.004; P=0.57; 95% confidence interval: -0.019-0.011). CONCLUSIONS: In this pilot study, we have demonstrated that RI evaluation via OCT is a promising technique that may be used for the assessment of skin hydration in vivo. However, the direct comparison of OCT with standard methods, ideally such as nuclear magnetic resonance spectroscopy, is necessary.  相似文献   
83.
Summary Using xenon-enhanced computed tomography for the study of cerebral blood flow, simultaneous measurements of end-tidal and arterial blood xenon concentrations using the blood collection method were performed to investigate the validity of substituting the end-tidal for the arterial blood xenon concentration. Simultaneous measurement by both methods was performed 68 times in 27 patients. There was no statistical correlation between the arterial blood accumulation rate constant obtained by arterial blood and end-tidal samples, nor between the arterial blood saturation value obtained by the two methods, even when correction was made for age. In brain tissue, all parameters calculated using the end-tidal concentration were lower than those using arterial blood. We therefore suggest that cerebral blood flow values calculated using end-tidal xenon concentration are useful only for qualitative cerebral blood flow mapping, and not applicable to absolute values of cerebral blood flow.  相似文献   
84.
经对292例正常胎儿枕额径和双顶径的外测量,结果表明,枕额径和双顶径都随着胎龄的增长而增大,但其生长速度则随着胎龄的增长而逐渐减慢。经回归分析原理,分别得出预测方程。枕额径增长的速度和双顶径增长的速度没有明显差异(P>0.05)。  相似文献   
85.
The time to loss of the adductor pollicis muscle response to ulnar nerve stimulation at 1 Hz (twitch) after succinylcholine, 1.5 mg.kg-1 intravenously (IV), or vecuronium, 0.1 mg.kg-1 (IV), administration was assessed visually in 134 children, age 2-13 yr, during clinically determined, deep halothane, enflurane and isoflurane anaesthesia. The overall time to twitch ablation and duration of succinylcholine's action is in agreement with published times obtained under controlled experimental conditions; the onset time following vecuronium is comparable to those observed during a similar anaesthetic background measured under controlled experimental conditions. Twitch ablation after succinylcholine was achieved in half the time needed following vecuronium regardless of anaesthetic agent. Succinylcholine's and vecuronium's onset time as well as succinylcholine's duration is adequately assessed by the outlined, simple clinical means. The choice of inhalation agent does not affect the time to visible twitch ablation in a clinically relevant manner; nor does it make an appreciable difference, in clinical terms, in succinylcholine's duration of action.  相似文献   
86.
亚硝酸盐法测定超氧化物歧化酶活性   总被引:1,自引:0,他引:1  
用亚硝酸盐、氰化钾抑制区别法测定样品中的 Cu,Zn-SOD 和 Mn-SOD,灵敏度高,重现性好,操作简便。实验表明,抑制率达50%时所需 SOD 的浓度为0.07 μg/ml,其批内和批间的变异系数分别为6.0%和5.5%,鸡肝 Cu,Zn-SOD 与 KCN 的抑制复合物的表观解离常数 K′为288.6±45.5 μmol。  相似文献   
87.
Platelet aggregationin vitro, deterioration of visual field defects (VFD) and the prevalence of disc haemorrhages (DH) were assessed in 49 patients with primary open angle glaucoma (POAG) and compared with the findings for 67 individuals with suspected glaucoma (GS) in a seven-year follow-up study (range 5.8 to 8.2 years). The percentage patients with spontaneous platelet aggregation (SPA) was higher for POAG patients with visual field deterioration (60%) than both POAG patients without progressive loss of visual fields (12.5%; P<0.005) and those with suspected glaucoma (22.4%; P<0.005). The occurrence of DH was higher among POAG patients with progressive loss of visual field (28%) compared to the GS group (8.4%; P<0.025) and the group of patients consisting of POAG patients without deterioration of VFD and GS (9.9%; P<0.05). DH also occurred more often in patients with low tension glaucoma (41.6%) than in the remaining POAG patients (13.5%; P<0.05). No relation between the patients with SPA and the patients with DH was observed.Abbreviations NPB normal platelet behavior - SPA spontaneous platelet aggregation - DH disc haemorrhage  相似文献   
88.
目的:测量下颌角间宽与颧弓深度、颧弓长度及下颌角厚度并进行相关分析,以期在活体上通过测量下颌角间宽来推算颧弓深度、颧弓长度、下颌角厚度,为临床行颜面美容矫治术及复合体的制作提供相关资料。方法:经福尔马林固定、颜面骨正常的成人男性尸体50具,按《人体测量方法》,用游标卡尺直接测量下颌角间宽、左右两侧颧弓深度与长度、下颌角厚度。结果:颧弓深度、颧弓长度、下颌角厚度与下颌角间宽其相关系数分别是,颧弓深度为0.649(P=0.001),颧弓长度为0.584(P=0.001),下颌角厚为1.0(P=0.001),颧弓深度、长度左、右无明显差别。结论:临床采用测量下颌角间宽来推算颧弓深度、颧弓长度及下颌角厚度具有显著性意义。  相似文献   
89.
90.
采用LabVIEW技术完成对心电、呼吸、无创血氧和无创血压信号的采集与处理,而后通过MATLAB模糊测量系统对采集的人体生理信号进行模糊预测分析。通过实验检验了人体生理信号检测、处理和模糊预测分析方法的可靠性。LabVIEW技术对人体生理信号的模糊预测分析是有效的,可用于检测阻塞性睡眠呼吸暂停患者的生理状态信号。  相似文献   
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