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991.
Akazawa Y Watanabe S Nobukiyo S Iwatake H Seki Y Umehara T Tsutsumi K Koizuka I 《Auris, nasus, larynx》2004,31(4):413-416
OBJECTIVE: We assessed the usefulness of computed tomography (CT) in cases of suspected impaction of fish bones in the esophagus. The findings of this study were also compared with those of studies in which surgery was used to remove or confirm the presence of fish bones. We accordingly propose a management protocol to ensure optimum outcome for patients with a history of fish bone ingestion. METHODS: X-ray and CT imaging were performed in 76 patients in whom esophageal impaction of fish bones was suspected. RESULTS: Plain X-ray revealed impacted fish bones in 17 patients (22%), soft-tissue swelling but no evidence of foreign body in 5 (7%), and no abnormal findings in 54 (71%). These findings were apparent on CT scans in 31 (41%), 8 (10%), and 37 (49%), respectively. Of the 31 patients in whom CT revealed a fishbone, 17 (55%) also exhibited X-ray evidence of foreign body. Of the remainder, X-ray revealed only soft-tissue swelling in 3 (10%), and was unremarkable in 11 (35%). Among the 5 patients in whom X-ray demonstrated only soft-tissue swelling, CT was positive for foreign body in 3 (60%). Of the 54 patients in whom X-ray appearances were normal, CT revealed foreign bodies in 11 (20%) and other abnormalities in 6 (11%). CONCLUSION: In the present study, sensitivity and specificity of plain X-ray was 54.8% (17 of 31) and 100% (45 of 45), respectively. However, for CT, both sensitivity and specificity were 100%. CT was determined to be very useful in the diagnosis of impacted fish bones in the esophagus. 相似文献
992.
Mechanisms of apoptosis induced by cisplatin in marginal cells in mouse stria vascularis 总被引:1,自引:0,他引:1
Lee JE Nakagawa T Kita T Kim TS Iguchi F Endo T Shiga A Lee SH Ito J 《ORL; journal for oto-rhino-laryngology and its related specialties》2004,66(3):111-118
Degeneration of the stria vascularis (SV) is amongst the major causes of cisplatin (CDDP)-induced hearing impairment. The pathways of apoptosis occurring in the SV due to CDDP were examined using a mouse experimental model. Temporal bones of adult C57BL/6 mice were collected on days 3, 7 and 14 after the local application of CDDP. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay and immunostaining for apoptosis-related proteins or reactive radical species were employed for analysis. Local application of CDDP caused apoptotic cell death of marginal cells 3 days after CDDP treatment. Immunohistochemical analyses demonstrated activation of caspase-3 and -9, but not -8, and redistribution of cytochrome c in affected marginal cells, indicating a caspase-dependent, mitochondrion-mediated apoptotic pathway in marginal cells. Temporary expression of hydroxynonenal, nitrotyrosine and inducible nitric oxide synthase in the SV was observed at the induction of apoptosis in marginal cells. CDDP toxicity generates reactive radical species in the SV, which causes mitochondrial membrane permeabilization leading to apoptosis of marginal cells. 相似文献
993.
Ichiro?TateyaEmail author Koichi?Omori Hisayoshi?Kojima Shigeru?Hirano Ken-ichi?Kaneko Juichi?Ito 《European archives of oto-rhino-laryngology》2004,261(9):489-492
Since 1990, we have performed steroid injection into the vocal fold by fiberoptic laryngeal surgery (FLS) under local anesthesia. In this study, the usefulness of this method was evaluated in 28 patients with vocal nodules. Under monitoring using a fiberoptic laryngoscope, a curved injection needle was inserted via the oral cavity and steroid was injected. Endoscopic findings showed that the vocal nodule had disappeared in 17 patients of the 27 patients and decreased in 10 after injection. The maximum phonation time was 10.9 s before operation and 13.9 s after operation, showing a significant increase (P<0.05), and the mean flow rate also showed a significant improvement (P<0.05). The patients self-rating concerning hoarseness demonstrated great improvement after injection. This technique can be performed under local anesthesia in combination with voice therapy on an outpatient basis, and it is considered to be useful for treating vocal nodules. 相似文献
994.
Ozaki S Miyata Y Arita M Takahashi M Haruta R Asahara T Kaneko M Kurisu K Kataoka T 《Hiroshima journal of medical sciences》2004,53(3-4):47-50
We report a rare case of neurofibromatosis type-2 (NF-2) associated with a chest wall schwannoma that was initially suspected of being a breast tumor. The patient was a 28-year-old female who was diagnosed as having NF-2 at 19 years old. At that time, she noticed a mass in the upper lateral region of her left breast but did not have it examined. The mass grew and became painful, and she was therefore referred to our department. Results of the initial examination indicated the possibility of a breast tumor, but a diagnosis of extramammary tumor of the major pectoralis major muscle was made on the basis of the results of ultrasonography and 3-dimensional computed tomography (3D-CT). An endoscope-assisted extirpation of the tumor was performed. Histologically, the tumor was an Antoni type A and B neurilemoma and was diagnosed as a schwannoma. 相似文献
995.
Alpha-eleostearic acid (9Z11E13E-18:3) is quickly converted to conjugated linoleic acid (9Z11E-18:2) in rats 总被引:2,自引:0,他引:2
Tsuzuki T Tokuyama Y Igarashi M Nakagawa K Ohsaki Y Komai M Miyazawa T 《The Journal of nutrition》2004,134(10):2634-2639
We previously showed that alpha-eleostearic acid (alpha-ESA; 9Z11E13E-18:3) is converted to conjugated linoleic acid (CLA; 9,11-18:2) in the liver and plasma of rats that were given diets including 1% alpha-ESA for 4 wk. In this study, we investigated this phenomenon in detail. First, the chemical structure of CLA produced by alpha-ESA administration was determined. After alpha-ESA was orally administered to rats, CLA in rat liver was isolated by HPLC. The positional and geometric isomerism was determined using GC-EI/MS and (13)C-NMR, respectively, and the CLA generated in rats after alpha-ESA feeding was confirmed to be 9Z11E-CLA. Next, the concentrations of alpha-ESA and CLA were determined 0, 3, 6, and 24 h after oral administration of alpha-ESA to rats. Moreover, we also investigated whether enteric bacteria are involved in the conversion of alpha-ESA to CLA using germ-free rats. alpha-ESA was orally administered to germ-free and normal rats and alpha-ESA and CLA were detected in the organs of both groups. In addition, to confirm that this reaction was enzyme-mediated, alpha-ESA was reacted with tissue homogenates (liver, kidney, and small intestine mucous) and coenzymes (NADH, NAD(+), NADPH, and NADP(+)), and the enzyme activities were estimated from the amount of CLA produced. CLA was detected when alpha-ESA was reacted with liver, kidney, and small intestine mucous homogenates and a coenzyme (NADPH). These results indicated that alpha-ESA is converted to 9Z11E-CLA in rats by a Delta13-saturation reaction carried out by an NADPH-dependent enzyme. 相似文献
996.
Takasuga T Inoue T Ohi E Kumar KS 《Archives of environmental contamination and toxicology》2004,46(4):419-431
Mono- through octachlorinated naphthalenes (PCNs) were measured in start-up, steady operation, and shutdown of machinery operation flue gas and fly ash generated during different stages of MSWI and other incineration thermal processes. Besides, electroprecipitator fly ash (EP-ash) was dechlorinated using the Hagenmeier process and analyzed for congener profiles. In addition to PCNs, polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), and major organochlorine pesticides were determined in ambient air samples from three different sites of western Japan in the summer and winter of 1992. The PCNs from flue gas contained 15,000, 4300, and 13,000 ng/m3 during start-up, steady operation, and shutdown conditions, respectively. Whereas fly ash contained 470, 370, and 1400 ng/g PCNs under start-up, steady operation, and shutdown condition, respectively. The dechlorination process reduced PCN concentrations considerably. Concentrations of PCNs and PCDD/PCDFs in air samples collected in winter were slightly higher than in summer. PCBs, organochlorine pesticides such as chlordanes, DDTs, and HCHs were higher in summer air samples. WHO toxic equivalency (WHO-TEQ) concentrations in air samples were 0.3–0.9 pg/m3 for PCDD/DFs and 0.029–0.31 pg/m3 for dioxin-like PCBs. 相似文献
997.
Conjugated eicosapentaenoic acid (EPA) inhibits transplanted tumor growth via membrane lipid peroxidation in nude mice 总被引:3,自引:0,他引:3
Both conjugated linoleic acid (CLA) and eicosapentaenoic acid (EPA) have an antitumor effect. Hence, we hypothesized that a combination of conjugated double bonds and an (n-3) highly unsaturated fatty acid would produce stronger bioactivity. To verify the antitumor effect of conjugated EPA (CEPA), we transplanted DLD-1 human colon tumor cells into nude mice, and compared the tumor growth between CEPA-fed mice and CLA- and EPA-fed mice. After tumor cell inoculation, mice were assigned to 1 of 4 groups (control, CLA, EPA, and CEPA) consisting of 10 mice each. The control group received only safflower oil fatty acids, whereas the remaining groups received a mixture of safflower oil fatty acids and 20 g/100 g of total fatty acids as CLA, EPA, or CEPA. Mice were fed once every 2 d for 4 wk at a dose of 50 mg/mouse at each feeding. After 4 wk, tumor growth in CEPA-fed mice was significantly suppressed, compared with that in CLA- (P < 0.005) and EPA-fed mice (P < 0.001). DNA fragmentation in the tumor tissues of the CEPA-fed mice occurred more frequently than in the CLA- (P < 0.001) and EPA-fed mice (P < 0.001), suggesting that CEPA induced apoptosis in the tumor tissues. To further investigate the mechanism, the level of oxidative stress in the tumor tissues was determined. The CEPA-fed mice showed significant lipid peroxidation, compared with the CLA- (P < 0.001) and EPA-fed mice (P < 0.001). Therefore, we verified that CEPA has a stronger in vivo antitumor effect than EPA and CLA, and that CEPA acts through induction of apoptosis via lipid peroxidation. 相似文献
998.
Reliability of intraocular pressure by Tono-Pen XL over amniotic membrane patch in human 总被引:1,自引:0,他引:1
PURPOSE: To determine the reliability of Tono-Pen XL in measuring intraocular pressure (IOP) over the amniotic membrane patch in human eyes. METHOD: Ten healthy volunteers (nine males and one female) participated in this study. After topical anesthesia, IOP was measured using the Tono-Pen XL before and after the application of a single-layer amniotic membrane patch in the right eye and double-layer amniotic membrane patch in the left eye. RESULTS: We found no statistical difference between the IOP measured with and without a single layer amniotic membrane (P = 0.808). Nor did we find any statistical difference between the IOP measured with and without double-layer amniotic membrane patch (P = 0.813). The average thickness of the single- and the double-layer amniotic membrane patch measured by pachymetry was 131.9 +/- 31.4 microm (mean +/- SD) and was 246.1 +/- 69.3 microm (mean +/- SD), respectively. CONCLUSIONS: This study showed that it is reliable to measure IOP by Tono-Pen XL over single or a double layer of amniotic membrane patch on healthy human eyes. Further studies are required to determine the accuracy of IOP measurement over amniotic membrane patch on diseased corneas. 相似文献
999.
The clinical free radical scavenger, edaravone, protects cochlear hair cells from acoustic trauma 总被引:1,自引:0,他引:1
Takemoto T Sugahara K Okuda T Shimogori H Yamashita H 《European journal of pharmacology》2004,487(1-3):113-116
It is known that reactive oxygen species have toxicity to the cochlea. We investigated the effect of edaravone, a free radical scavenger for clinical use, on the cochleae of guinea pigs subjected to acoustic trauma. We assessed auditory brainstem response (ABR) thresholds to evaluate cochlear function and observed the sensory epithelium. After noise exposure (130 dB SPL, 3 h), we observed that the auditory brainstem response threshold shift in edaravone-treated ears was significantly less than that in untreated ears. This result suggests that edaravone protected the cochleae from acoustic trauma. 相似文献
1000.
Yu M Cambj-Sapunar L Kehl F Maier KG Takeuchi K Miyata N Ishimoto T Reddy LM Falck JR Gebremedhin D Harder DR Roman RJ 《European journal of pharmacology》2004,486(3):297-306
This study examined the effects of a 20-hydroxyeicosatetraenoic acid (20-HETE) antagonist, 20-hydroxyeicosa-6(Z),15(Z)-dienoic acid (WIT002) and two agonists, 4-amino-N-(20-hydroxy-eicosa-5(Z),14(Z)-dienoyl) benzenesulfonamide (ABSA) and 20-hydroxyeicosa-5(Z),14(Z)-dienoic acid (WIT003), on the diameter of rat middle cerebral arteries in vitro and on cerebral blood flow in vivo. WIT003, ABSA and 20-HETE all had a similar effect to reduce the diameter of the middle cerebral artery by 26%. WIT003 and 20-HETE both increased intracellular Ca2+ concentration ([Ca2+]i) in vascular smooth muscle cells isolated from the middle cerebral artery. In contrast, WIT002 had no effect on the basal diameter of the middle cerebral artery but it attenuated the vasoconstrictor responses and the rise in [Ca2+]i in vascular smooth muscle cells following administration of 20-HETE and 5-hydroxytryptamine (5-HT). WIT003 partially restored the vasoconstrictor response to 5-HT in the middle cerebral artery after administration of an inhibitor of the endogenous synthesis of 20-HETE. Infusion of the 20-HETE agonists, WIT003 and ABSA, into cisterna magna of rats reduced baseline cerebral blood flow by 20%, whereas administration of the 20-HETE antagonist, WIT002, had no effect. Intracisternal injection of WIT002 attenuated the fall in cerebral blood flow following injection of blood into the cisterna magna, whereas administration of the 20-HETE agonist, ABSA, potentiated this response. These findings indicate that the 20-HETE agonists, WIT003 and ABSA, increase cerebral vascular tone both in vivo and in vitro and suggest blocking the vasoconstrictor actions of 20-HETE may be useful to prevent the acute fall in cerebral blood flow following subarachnoid hemorrhage. 相似文献