Influence of Sodium Hyaluronate Concentration on Corneal Aberrations in Soft Contact Lens Wearers

Jong Soo Lee,Jong Moon Park,Hyun Kyung Cho,Su Jin Kim,Hyoun Do Huh2,Young Min Park 대한안과학회 2018 Korean Journal of Ophthalmology Vol.32 No.2

Purpose: This study aimed to evaluate the influence of varying concentrations of sodium hyaluronate (SH) eye drops on corneal aberrations in normal individuals wearing silicone hydrogel contact lenses. Methods: Normal individuals wearing silicone hydrogel contact lenses were enrolled in this study. Subjects were classified into two groups depending on the concentration of the preservative-free SH used (group 1, 0.1% SH; group 2, 0.3% SH). All subjects were asked to blink five times after instillation of the SH eye drop and before the Galilei measurements. Corneal aberrations were measured over the contact lenses before and after SH eye drop instillation. Visual acuity (VA) over the contact lenses was also measured both before instillation of the SH eye drop and after the subjects completed the five blinks. Results: There was no change in VA after SH instillation in group 1; however, group 2’s VA significantly deteriorated after SH instillation. Changes in VA after SH instillation compared to baseline were significantly higher in group 2 than in group 1. Similarly, the increase in corneal aberrations after SH instillation was significant in group 2 but not significant in group 1. Among the significantly increased corneal aberration parameters, defocus was the main type in group 2. Changes in corneal aberrations after SH instillation compared to baseline were significantly higher in group 2 than in group 1. Conclusions: A 0.3%-concentration of SH increases corneal aberration and decreases VA in soft contact lens wearers. Defocus is the main type of aberration that increased in the 0.3% SH instillation group.

천마의 항경련작용기전 연구

허근,이수진,신억섭,박종민 영남대학교 약품개발연구소 1996 영남대학교 약품개발연구소 연구업적집 Vol.6 No.-

Gastrodia elata is a medicinal plant which has been used as anticonvulsant in Korea, Japan and China. This study was conducted to examine the action mechanism of Gastrodia elata centering around the change of GABA and glutamic acid level in brain while observing the anticonvulsive effect in PTZ-induced seizure model Seizures were reduced effectively by pretreatment of ether soluble part of methanol extract of, Gastrodia elata. The pretreatment of ether soluble part inhibited not only the decreses of brain GABA level but also the increase of brain glutamic acid level observed in PTZ model of convulsive dose. Although there was not any change in glutamic acid level, the same development was also observed in the model of subconvulsive dose. From above results, it seems that the anticonvulsive component of Gastrodia elata is lipophilic, and its action mechanism is originated from both control action of GABA level and inhibition of glutaminergic neurotransmission.

바코드 자동부착 시스템을 이용한 생산정보의 효율적인 관리

허성관,박종락,임승환,정종태 대한설비관리학회 2004 대한설비관리학회지 Vol.9 No.1

On this thesis, We studied on effective management of manufacturing information using auto bar code attachment system. Nowdays, Management Information System is essential factor to manage a company. This paper used bar code system to obtain data and dealing with data. And, In this paper, We proposed the method of development about auto bar code label attachment system for manufacturing process. we show the way of stepping motor control, bar code printer and

Drosophila melanogaster의 Hybrid Dysgenesis에 관한 연구 Ⅳ. P-M System 에 의한 한국산 노랑초파리 자연집단의 분석

허미경,추종길 中央大學校 遺傳工學硏究所 1989 遺傳工學硏究論集 Vol.2 No.1

In the P-M system of Hybrid dysgenesis, strains of Drosophila melanogaster can be classfied by sterility tests as P, M and Q. The present paper repots on the distribution of P, M and Q types in the P-M system in Korean natural populations. In 15 strains collected from various sites of korea, five strains were analysed by Q in which they did not produce appreciable gonadal dysgenesis with P males or with M females, and 10 strains were M types. They were examined with respect to the two components of the P-M system, chromosomal P factor and the extrachromosomal cytotypes. The P factors active for potential GD sterility were found at very low frequencies, and the M cytotype which causes susceptility to the P factor is predominant in most strains. But the observation of intermediate and different levels of GD sterility suggests the existance of P factors and cytotype polymorphism in these populations.

예열된 디젤연료의 분무특성에 미치는 영향에 관한 연구

허종철,이규영 제주대학교 1994 논문집 Vol.39 No.-

The correlations between the spray tip penetration and the spray angle were investigated by the direct photographic method under the various conditions of injection pressure, ambient gas pressure and preheated fuel. With the increase of ambient gas pressure, the spray tip penetration was decreased and the spray angle was increased. The transition point in the spray tip penetration was observed at the higher ambient gas pressures and strongly depended upon the fuel temperature. The spray angles in the case of preheated fuel were larger than those of non-preheated fuel conditions. Particularly, the spray angle at ambient gas pressure of 1.5 and 3MPa was sharply increased due to the result of change of fuel properties, but the spray tip penetration was decreased. The initial stage of fuel spray showed the form of non-disintegrated intact core, but the formation of ligament increasingly was developed with the increase of th fuel temperature.

英語否定極語의 分析方法

許鍾會 尙志大學校 1990 論文集 Vol.11 No.-

Loader/Unloader의 고속화에 관한 연구

허성관,권용규,최종탁 大邱大學校 科學技術硏究所 2000 科學技術硏究 Vol.7 No.2

In the recent loader & unloader, left controller has problems such as functional error caused by vibration when speed up and discordance of speed between another machine in line. On this study, a newly designed loader & unloader has been selected motor viewed in torque, revolutions per minute (RPM). rating and output of power, programmable logic controller(P. L. C) viewed in economy, convenience and manageme -nt. By using optimum inverter, it can be avoided from occurrence of high frequence and motor damage in these equipments. By establishing distributed control system(D. C. S), it can control input, output and production units, can contribute factory automation system in PCB manufacture.

전기경련요법의 심전도에 대한영향

허민이수근,김종길,이수근 大韓神經精神醫學會 1990 신경정신의학 Vol.29 No.4

This study was conducted to determine the electrocardiographic effects during modified electroconvulsive therapy. A series of 22 patients were submitted to 228 electric convulsions which had been modified by he intravenous injection of ultra-short-acting barbiturates and muscle relaxant. Electrocardiograms were taken before, during and after(4 and 1/2 hours later) the convulsive stage. During convulsive stage, a marked degree of sinus tachycardia was usual, S-T segment depression(2 mm. or more) developed in four cases and sinus arrhythmia was recorded in one case. These irregularities disappeared after convulsive stage. In 3 cases with clinical or electrocardiographic evidence of mild heart diseases, no serious cardiovascular disturbance occurred. With this study results, we conclude that modified electroconvulsive therapy is safe if we follow precautions of treatment procedures.

자동차 급가속 방지장치 개발

허성관,김성욱,정종태 대구대학교 산업기술연구소 2003 産業技術硏究 Vol.15 No.1

A lot of private and social loss have been happened in quick start of car, which makes car drivers physical and emotional stress. This study is to develop a device for preventing quick start of car. The developed device can prevent the quick start of car under engine rotation rate is over 3,500 RPM and is easy to control the lever and other devices in car.

OBD-2의 열 변색 현상에 관한 열역학적 연구

許永德,金明建,金鍾珪 단국대학교 1995 論文集 Vol.29 No.-

The termochromism of OBD-2 has been examined. The OBD-2 exists as a colorless lactone in aprotic solvents. However, the OBD-2 exists in the form of an equilibrium imxture of a colored zwitter-ion and a colorless lactone in protic solvents. When an acid is added to the solution, the OBD-2 exists and equilibrium mixture as a colorless lactone and a colored cation even in aprotic solvents. In order to understand the interaction between the OBD-2 and the solvent, absorption spectra of the OBD-2 in various solvents were measured. The systematic increase of the λ_max of the OBD-2 correlate with the hydrogen-bond donor ability of the solvent in neutral solution. The thermodynamic parameters of the OBD-2 has also been investigated. From the variation of absorbance with temperature, the standard enthalpy changes △H^0 of the equilibrium between the lactone and the zwitter-ion in various solvents have been determined. The standard enthalpy change △H^0 is approximately -7 kJ/mol in protic solvents. In acidic solution, the standard enthalpy change is measured to be to zero in protic solvents within the experimental error. When the carboxylic group is protonated in acidic solution, a poor interaction between the dye and the solvent is expected.