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991.
Kim DY Kim LS Kim KH Sung MW Roh JL Kwon TK Lee SJ Choi SH Wang SG Sung MY 《Acta oto-laryngologica》2003,123(9):1102-1109
OBJECTIVES: Videostrobokymography (VSK) has recently been introduced. The aim of this study was to analyze vibratory patterns and objective parameters in various benign vocal fold lesions using VSK and to examine the efficacy of VSK in clinical applications. MATERIAL AND METHODS: Using VSK, we analyzed the vibration patterns of normal vocal folds, various benign lesions such as nodules, polyps, cysts and Reinke's edema and cases of unilateral vocal fold paralysis. We also calculated the objective parameters open quotient and asymmetric index and compared them with their mean values in normal controls. RESULTS: In nodules, polyps and cysts, the open quotient at the site of the lesion was similar to the mean value in the normal controls; however, on the other parts of the vocal folds, it was much larger than the normal mean value. In Reinke's edema, irregular and asymmetric vibrations were observed. The posterior area of the vocal folds showed larger open quotients than the anterior area. In unilateral vocal fold paralysis, irregular vocal fold vibration and incomplete closure of the vocal folds were documented. Much larger asymmetric indices were calculated for unilateral vocal fold paralysis than in normal controls or for other lesions. The asymmetric index may be a good quantitative parameter of vibration in patients with vocal fold paralysis. CONCLUSION: This study demonstrated that VSK could generate clear quantitative documentation of fine vibrations of vocal folds in many different types of benign lesion. VSK has the potential to be an effective tool for the quantitative analysis of vibratory patterns of vocal folds in clinical settings. 相似文献
992.
Lee JE Nakagawa T Kim TS Iguchi F Endo T Dong Y Yuki K Naito Y Lee SH Ito J 《The Laryngoscope》2003,113(6):994-999
OBJECTIVES/HYPOTHESIS: The survival of the spiral ganglion (SG) is a critical issue in preservation of hearing. Research on topics related to this issue requires a mouse experimental model because such a model has advantages including use of genetic information and knockout or "knockin" mice. Thus, the aim of the study was to establish a mouse model for induction of apoptosis of SG neurons with a definite time course. STUDY DESIGN: Laboratory study using experimental animals. METHODS: C57BL/6 mice were used as experimental animals and were subjected to direct application of cisplatin into the inner ear. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay and immunostaining for Neurofilament 200-kD (NF) and peripherin were used for analysis of SG degeneration. In addition, generation of peroxynitrite in affected spiral ganglions was examined by immunostaining for nitrotyrosine. Cellular location of activated caspase-9 and cytochrome-c in dying SG neurons were examined for analysis of cell death pathway. RESULTS: The TUNEL assay and immunohistochemical analysis for NF and peripherin indicated that type I neurons in spiral ganglions were deleted through the apoptotic pathway over time. Spiral ganglion neurons treated with cisplatin exhibited expression of nitrotyrosine, indicating induction of peroxynitrite by cisplatin. In dying SG neurons, expression of activated caspase-9 and translocation of cytochrome-c from mitochondria to cytoplasm were observed, indicating the mitochondrial pathway of apoptosis. CONCLUSION: The predictable fashion of induction of apoptosis in SG neurons over a well-defined time course in the model in the study will aid studies of the molecular mechanism of cell death and elucidation of a strategy for prevention of SG degeneration. 相似文献
993.
Various causes and clinical characteristics in vertigo in children with normal eardrums 总被引:7,自引:0,他引:7
Choung YH Park K Moon SK Kim CH Ryu SJ 《International journal of pediatric otorhinolaryngology》2003,67(8):889-894
OBJECTIVE: The differential diagnosis of vertigo in children is extensive. Otitis media and middle ear effusion could be the most common causes of vertigo in children, but there are some problems in detecting the other causes for vertigo because they are one of most frequent diseases of childhood. The purpose of this study is to review the clinical characteristics and both the audiological and vestibular findings of vertigo in children with normal eardrums, who do not show otitis media or middle ear effusion, and to assist in making a differential diagnosis of vertigo. METHODS: The fifty five children (< 16 years old) with vertigo, who visited the Department of Otolaryngology, Ajou University Hospital, Suwon, South Korea between January 1995 and December 2001 were selected for this study. These excluded the patients with abnormal eardrums/tympanograms or those that did not perform questionnaires, audiological, or vestibular evaluations. They were retrospectively analyzed for clinical symptoms, vestibular functions, and differential diagnosis. RESULTS: The most common causes for vertigo in children were migraine in 17 (30.9%) and benign paroxysmal vertigo of childhood (BPVC) in 14 (25.5%). Other less frequent causes included four cases of trauma, two cases each of Meniere's disease, delayed endolymphatic hydrops, benign positional vertigo, and one case only for cerebellopontine angle tumor, seizure, acute vestibular neuritis, juvenile rheumatoid arthritis, leaving ten cases (18.2%) as unclassified. Abnormal findings were noted in 13 (23.6%) in pure tone audiogram, 3 (5.5%) in positioning test, 6 (10.9%) in bithermal caloric test, and 36 (65.5%) in rotation chair test. CONCLUSIONS: The vertigo in children with normal eardrums, who did not show otitis media or middle ear effusion, was most commonly caused by migraine and BPVC. These findings have shown to be very different from those with adult vertigo. The evaluation of vertigo in children requires a questionnaire for extensive and complete history taking, audiograms and vestibular function tests. And in selected cases, electroencephalography, hematological evaluation, imaging of the brain or temporal bone should be performed. 相似文献
994.
OBJECTIVE: The purpose of this study was to determine the radiologic results of nasopharyngeal carcinoma (NPC) that showed complete responses on follow-up imaging studies after radiation therapy. MATERIALS AND METHODS: This study is a retrospective review of 23 patients (18 male, 5 female, aged 15-71 years; mean age, 48.5 years) affected with NPC, from August 1995 to July 2000, who were examined with magnetic resonance imaging or computed tomography scan before and after either radical radiotherapy or chemoradiotherapy. The median follow-up was 24.7 months and ranged from 12 to 48 months. We analyzed the primary tumors by ascertaining/measuring tumor size, depth, middle ear effusion, skull base invasion, and lymphadenopathy. The treatment responses for primary tumors were classified as either atrophy, scar (asymmetric elevation without enhancement), or normalized. The tumor response and the appearance of bone regeneration in the previous destructive part of the skull base were also recorded. RESULTS: The 23 patients consisted of 12 superficial tumors, for whom treatment results were normalized in 10, atrophy in 1, and scar in 1 and 11 deep tumors for whom treatment results were scar in 6, normalized in 3, and atrophy in 2. Skull base invasion was detected in 6 patients, 5 of whom showed complete healing of skull base destruction after radiotherapy. However, the other patient exhibited an unusual hyperostotic change in the skull base mimicking fibrous dysplasia of the skull base. CONCLUSIONS: The superficial tumors tended to be radiologically normalized even when they were large. However, the deep tumors mainly changed to scar after radiation therapy. On the other hand, skull base invasion could be normalized after radiotherapy. 相似文献
995.
996.
Ziavra NV Yen Pik Sang FD Golding JF Bronstein AM Gresty MA 《Mayo Clinic proceedings. Mayo Clinic》2003,78(5):574-578
OBJECTIVE: To compare the effects of breathing supplemental oxygen vs air on alleviating motion sickness in healthy adults. SUBJECTS AND METHODS: Between April and July 2002, 20 healthy subjects were exposed to a provocative motion on 2 occasions (1-week interval) according to a randomized, counterbalanced, crossover design. During motion, subjects rated their nausea (1, no symptoms, to 4, moderate nausea) every 30 seconds. Once mild nausea occurred, subjects began breathing supplemental oxygen or air through a face mask. Motion ceased when moderate nausea occurred, but subjects continued breathing study gases for 5 minutes while recovering. Recovery was assessed for 20 minutes after motion. RESULTS: There were no significant differences in the rate of increase in symptom severity or the rate of recovery between the 2 conditions. CONCLUSION: Breathing supplemental oxygen had no advantage over breathing air in reducing motion sickness in healthy adults. 相似文献
997.
Laser Punch-Out for Acne Scars 总被引:6,自引:0,他引:6
Patients with acne scars want smooth facial skin. However, achieving this is difficult with dermabrasion or chemical peeling.
Nor can acne scars be covered with cosmetics, due to their ice-picked or cobblestone appearance. Laser resurfacing is more
effective and safer than other conventional methods due to its precision with depth control and variable methods of surface
cutting. Even depth resurfacing with a laser shows unsatisfactory results, therefore, for the deep-sited acne scar the cutting
methods have to be changed according to the depth and pattern of the scar. For 2 years, starting in January 1996, we treated
71 patients with a high-powered CO2 laser (Ultrapulse). Different resurfacing methods were applied according to the depth and pattern of the scars. For mild
depressed scars, even depth resurfacing was done. For moderate-depth acne scars, the shoulder technique was also used. For
the deepest and ice-picked scars, the laser punch-out was combined. Laser resurfacing was carried out at 300–500 mJ, with
two to five passes. Laser punch-out was done at 500 mJ, with three to seven continuous passes on the ice-picked scar. From
the pathologic findings of acne scars showing that there was thick intradermal scar, we knew that laser punch-out was necessary
for improvement of acne scars. Depth-wide, the ice-picked scars improved by over 80% and the sharp demarcated margin of the
acne scar faded out. Most of the patients with acne scars were satisfied with laser resurfacing. Only six patients had a second
laser treatment, with an interval of 12 months. There were no hypertrophic scars after laser resurfacing, but erythema lasted
for 3–12 months. Patients taking oral retinoic acid were not contraindicated for laser resurfacing but required special caution
because they had atrophic skin and delayed wound healing. Laser resurfacing is the most versatile method for acne scars, with
a high-powered CO2 laser. The laser punch-out method is better than even depth resurfacing for improving deep acne scars and can be combined
with the shoulder technique or even depth resurfacing according to the type of acne scar. 相似文献
998.
Gertsik GIa Zmievskoĭ GN Ivantsov VI Sang Min Li Iu Byiung Kim Gil Von Iun 《Meditsinskaia tekhnika》2001,(3):29-35
A procedure is proposed to search for acupuncture points and channels (APC) by space-sensitive recording of optical radiation diffusely reflected by surface (dermal and hypodermal) tissues of the body. For this purpose, the body surface is probed by low-intensity infrared radiation from a laser or noncoherent (light-emitting diodes) source by using a fiber-optic multichannel sensor. It is shown that it is most advisable to apply sources at wavelengths of 840-850 and 1260-1300 nm. 相似文献
999.
Anticoagulant activity of sulfoalkyl derivatives of curdlan 总被引:1,自引:0,他引:1
Lee KB Bae JH Kim JS Yoo YC Kim BS Kwak ST Kim YS 《Archives of pharmacal research》2001,24(2):109-113
Curdlan is a natural beta-1,3-glucan produced by Agrobacterium biovar 1. In this study, the anticoagulant activity of sulfoalkyl derivatives of curdlan was investigated by carrying out activated partial thromboplastin time (APTT) assay and compared with that of o-sulfonated curdlan. Approximately 100-fold higher concentration of o-sulfonated curdlan than heparin was required to obtain the same level of the clotting time. Anticoagulant activity of curdlan derivatives was dependent on the degree of sulfation in prolonging the clotting time. However, the chain length of the substituent did not play a role in prolonging the clotting time. The curdlan derivatives enhanced thrombin inhibition by mediating through antithrombin III. The inhibition of thrombin by o-sulfonated curdlan was found to be approximately 10-fold weaker than that by heparin. 相似文献
1000.
Stimulation of mammary tumorigenesis by systemic tissue inhibitor of matrix metalloproteinase 4 gene delivery 总被引:13,自引:0,他引:13
Tissue inhibitors of matrix metalloproteinase (TIMPs) are multifunctional proteins with both matrix metalloproteinase (MMP) inhibitory effects and growth-regulatory activity. TIMPs inhibit MMP activity, suggesting a use for cancer gene therapy. However, here we report that systemic administration of human TIMP-4 by electroporation-mediated i.m. injection of naked TIMP-4 DNA stimulates tumorigenesis of human breast cancer cells in nude mice. Consistent with tumor stimulation, TIMP-4 up-regulates Bcl-2 and Bcl-X(L) protein. TIMP-4 also inhibits apoptosis in human breast cancer cells in vitro and mammary tumors in vivo. A synthetic MMP inhibitor BB-94 did not have such antiapoptotic effect. Analysis of TIMP-4 expression in human mammary specimens indicates that TIMP-4 protein is increased in mammary carcinoma cells compared with normal mammary epithelial cells. These data indicate an antiapoptotic activity in breast cancer cells and a tumor-stimulating effect of TIMP-4 when administrated systemically. 相似文献