http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
박용호,구본석,박찬일,박용호,김용민 대한이비인후과학회 2005 대한이비인후과학회지 두경부외과학 Vol.48 No.10
Osteomas in the head and neck regions are uncommon benign lesions and usually found in the front ethmoid area. Temporal bone osteoma is an extremely rare entity. When it is located in the temporal bone, it may cause various symptoms such as hearing loss, tinnitus, vertigo, facial palsy and cosmetic deformities such as auricular protrusion and external mass. We report, with a short review of the relative literature, a case of large osteoma that originated from a squamomastoid portion of the temporal bone in a female patient of 20 years old.
Stem Cell Therapy for Sensorineural Hearing Loss, Still Alive?
박용호 대한청각학회 2015 Journal of Audiology & Otology Vol.19 No.2
In mammals, the auditory system, which includes the cochlea, has a very complex structure harboring many types of cells performing different functions. Among these cells are the auditory hair cells (HCs), which are terminally and well differentiated unique cells which have lost their regenerative potential after development. The auditory HCs are easily damaged by aging as well as during episodes of ototoxicity and acoustic trauma. HCs damages typically occur in the early stage of injury and can result a permanent hearing loss. Recently, there have been tremendous developments from stem cells (SCs) research involving sensorineural hearing loss, but several limitations and obstacles persist in allowing these developments from continuing onto clinical applications. This review discusses the recent advances in SC research in sensorineural hearing loss with the subsequent sections discussing the possible hurdles and limitations that currently preclude their clinical application.
박용호,문동철,염만오,Pak, Yong-Ho,Moon, Dong-Cheol,Yum, Man-Oh 한국정밀공학회 1995 한국정밀공학회지 Vol.12 No.11
The fluid coupling combined with a pump and a turbine have many merits compared with other couplings, their uses are increesing rapidly in various industrial fields at home and abroad in pursuit of high-speed more efficiency durability of various mechanic devices. The authorities concerned have recognized the improtance of the fluid coupling and supported its developement and now some trial products began to show up. As the structrue and characteristics of the fluid coupling have little similarity to other kinds of couplings and its fluid behavior is unique, so its characteristic analysis is expected to be difficult. Until now no satisfactory study on the characteristics of the fluid coupling seems to have been conducted at home, so a study on this field needs to be done urgently. The purpose of this research is to construct the experimental test set-ups and establish a series of performance test program for the domestically developed fluid couplings and to provide a software to store and utilize these experimental data which can be used to improve the performance of the fluid coupling and solve on the job problems confronted in operation. The performance test consists of taking measurment of torque, rpm and efficiency of the fluid coupling for three different amount of working fluid inside with various loads to the output shaft and finally infestigating the torque, rpm and efficiency characteristics of the fluid coupling with respect to these parameters. The results of this study can contribute valuable references to the development of variable speed fluid coupling and torque converter currently pursued by the domestic industry.
박용호,이용원,박석원,구본석,김용민,나기상,박찬일 대한이비인후과학회 2005 대한이비인후과학회지 두경부외과학 Vol.48 No.10
Background and Objectives:With the advancement of modern civilization and mechanical development of society, the prevalence of noise-induced hearing loss is increasing. There were some suggestions that noise-induced hearing loss may be reduced or prevented with antioxidant treatment. The purpose of this study is to evaluate the effect of ebselen as a free radical scavenger or antioxidant in noise-induced cochlear damage. Materials and Method:Thirty male Sprague Dawley rats (250- 300 g) with normal auditory brainstem response (ABR) thresholds were exposed for 6 h to 115 dB SPL broad band noise. 10 mg/kg ebselen were injected intraperitoneally at 12 h before and 1h before noise exposure. After noise exposure, auditory brainstem response threshold shifts were evaluated. A study for iNOS and nitrotyrosine expressions in the cochlea was examined by immunohistochemical staining. Results:After the noise exposure, auditory brainstem responses indicated that ebselen treatment reduced threshold shifts significantly. The expression of iNOS and nitrotyrosine were observed in hair cells, supporting cells of the organ of Corti, stria vascularis and spiral ganglion. The expression of iNOS and nitrotyrosine were lower in the ebselen treated group than in the non-treated group. Conclusion:Ebselen protects cochlea from noise by playing a role as a scavenger of reactive free radicals.
전해부상에서 전압과 극판 재질에 따른 미세기포의 크기 특성
박용호,한무영 대한상하수도학회 2002 상하수도학회지 Vol.16 No.6
Electro-flotation (EF) has shown advantages, such as a high removal efficiency and easy control of bubble generation, over dissolved air flotation. However, the fundamental characteristics of the process have not been investigated in detail. According to recent modeling results from trajectory analysis, the size of the bubble is one of the most important factors that affect the efficiency of collision between bubble and particle. In this paper, the size characteristics of bubbles generated from EF under various conditions are measured using a new method for bubble size measurement, the Particle Counter Method (PCM). The size of the generated bubbles was found to be constant with respect to applied voltage but to vary with the electrode materials. These results and their implications are discussed.
실험적으로 유발한 기니픽 난청모델에서 청각피질과 시각피질의 c-fos 면역반응력 변화
박용호,김수일,박재용,구본석,김용민,나기상 대한이비인후과학회 2008 대한이비인후과학회지 두경부외과학 Vol.51 No.7
Recently, functional studies for auditory cortex are being watched with interest in accordance with development of many radiologic equipments and surgical devices for sensorineural hearing loss. Moreover, it is well known that the function of central auditory pathway is essential for hearing rehabilitation. There are some papers that reported about the functional or metabolic changes of auditory cortex in deafness and in patients with cochlear implantation. The aim of this study was to investigate indirectly the metabolic changes of primary auditory cortex and visual cortex in the c-fos immunoreactivity in an experimentally induced permanent threshold shift animal model. Materials and Method:Ototoxic drugs (kanamycin and furosemide) and noise were used for the induction of permanent threshold shift. Cochlear damages were evaluated with auditory brainstem responses (ABR) and morphologic studies. The c-fos immunoreactivity was observed with a lapse of time after deafening. Results:After the administration of ototoxic drugs and noise exposure, ABR threshold shifts were not recovered until after three months. Cochlear damages were observed in broad areas of cochlea. The c-fos immunoreactivity in the primary auditory cortex was increased during the acute period but it was decreased after one month. In addition, it was recovered again within the level of control three months later. In the visual cortex, increased and sustained immunoreactivities were observed after the drug and noise exposure. Conclusion:This result shows the plasticity of auditory cortex and possibility of some kinds of auditory-visual cross modal plasticity. (Korean J Otorhinolaryngol-Head Neck Surg 2008;51:602-8)