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991.
The technique in endoscopic posterior septoplasty for the case of a female aged 49 with bilateral choanal stenosis is presented. This female had undergone endoscopic nasal surgery for stenosis twice before the posterior septoplasty. However, restenosis of the choanae had arisen within 2 weeks after each surgery. This patient underwent the endoscopic posterior septoplasty under general anesthesia. After removal of the cartilage and bony structures of the nasal septum, the posterior one-third of bilateral septal membranes was excised. This technique is to enlarge the choanal opening obliquely. Excellent visualization for the septoplasty using the endoscope was obtained. Sufficient patency of the choanae was achieved using this technique. There still is no restenosis of the choanae observed and the rhinomanometry shows extreme decrease of nasal airway resistance 1 year after this surgery. It is considered that endoscopic posterior septoplasty for choanal stenosis is an effective procedure with low morbidity and long-term patency. 相似文献
992.
Nagasawa S Yoshida T Terashima N Mizoguchi T Yagasaki H Kamijo K Ito M Platt JA Oshida Y 《Dental materials journal》2005,24(1):140-148
The thermal expansion rate, coefficient of thermal expansion, and high temperature strength of two types of commercially available alloy for metal-bond porcelain, KIK-HII (KIK) and Degubond-J2 (J2), were evaluated up to the liquidus point temperature using a thermo-mechanical analyzer. Furthermore, microstructure in the solid-liquid coexisting region was observed for evaluation. Our results revealed the following findings: 1. For KIK, solidus point was 1,209.3 +/- 3.2 degrees C, liquidus point was 1,308.3 +/- 7.10 degrees C, and melting expansion rate was 0.41+/- 0.16%. 2. For J2, solidus point was 1,198.3 +/- 0.6 degrees C, liquidus point was 1,253.0 +/- 4.4 degrees C, and melting expansion rate was 4.50 +/- 0.80%. 3. At high temperature, the mechanical characteristics of KIK greatly differed from those of J2. The risk of causing deformation during porcelain baking was suggested for KIK. Removal of segregation during casting was considered difficult in J2. 相似文献
993.
Use of a tongue-pressure measurement system to assist fabrication of palatal augmentation prostheses
Makihara E Masumi S Arita M Kakigawa H Kozono Y 《The International journal of prosthodontics》2005,18(6):471-474
PURPOSE: The purpose of this study was to determine a baseline value of tongue pressure on the palatal region in normal subjects that could then be used to assist in fabrication of a palatal augmentation prosthesis (PAP). MATERIALS AND METHODS: A tongue-pressure measurement system with 36 rubber pressure sensors was constructed for this study. This system was applied to 16 normal subjects, and the tongue pressure on the palatal region was measured when they were swallowing. RESULTS: The maximum tongue pressures seen during swallowing were 85.0 g/cm2 in the early stage, 95.0 g/cm2 in the middle stage, and 93.0 g/cm2 in the late stage. The average maximum tongue pressure throughout swallowing was 91.0 g/cm2. The tongue pressure in the early stage ranged from 3.37 g/cm2 to 8.74 g/cm2. A significant difference was found between the anterior and the posterior regions and between the central and the posterior regions. The value in the middle stage ranged from 5.32 g/cm2 to 10.22 g/cm2. Significant differences were found between the anterior and the posterior regions and between the central and the posterior regions. Values in the late stage ranged from 6.80 g/cm2 to 7.91 g/cm2. CONCLUSION: The average maximum tongue pressure against the palate of approximately 90 g/cm2 suggests that a PAP sufficient for swallowing should be strong enough to withstand this amount of pressure. The device is also useful to check for variations in the tongue contact area during trial of the prosthesis. 相似文献
994.
Endothelial nitric oxide contributes to the renal protective effects of ischemic preconditioning 总被引:4,自引:0,他引:4
Yamasowa H Shimizu S Inoue T Takaoka M Matsumura Y 《The Journal of pharmacology and experimental therapeutics》2005,312(1):153-159
We determined whether endothelial nitric oxide synthase (eNOS) plays an important role in the renal protective effect of ischemic preconditioning (IP) against the ischemia/reperfusion-induced acute renal failure (ARF) by using eNOS-deficient (eNOS(-/-)) and wild-type (eNOS(+/+)) mice. Ischemic ARF was induced by occlusion of the left renal artery and vein for 45 min followed by reperfusion, 2 weeks after contralateral nephrectomy. IP, which consists of three cycles of 2-min ischemia followed by 5-min reperfusion, was performed prior to 45-min ischemia. In eNOS(+/+) mice, IP treatment markedly attenuated the ischemia/reperfusion-induced renal dysfunction and significantly improved histological renal damage such as tubular necrosis, proteinaceous casts in tubuli, and medullary congestion. Constitutive nitric oxide synthase activity in the kidney without IP was markedly decreased 6 h after reperfusion, but this decreased response was not observed in eNOS(+/+) mice with IP treatment. The improvement of renal dysfunction in eNOS(+/+) mice with IP treatment was abolished by pretreatment with N(G)-nitro-l-arginine, a nonselective NOS inhibitor, whereas aminoguanidine, an inducible NOS inhibitor, had no effect. Finally, no protective effects of IP on ischemia/reperfusion-induced renal dysfunction and histological damage were observed in eNOS(-/-) mice. These findings strongly support the view that eNOS-mediated NO production plays a pivotal role in the protective effect of IP on ischemia/reperfusion-induced ARF. 相似文献
995.
The present study investigated smoking prevalence and attitudes toward smoking in student and staff nurses, and activities to promote tobacco intervention by staff nurses. A total of 743 student nurses in 2 colleges and one university and 490 staff nurses in the university hospital in Niigata, Japan participated in the study and filled in self-administered anonymous questionnaires focused on smoking habits, attitudes toward smoking, and activities to promote tobacco intervention. The smoking prevalence among student nurses was 6% and increased with the year of study, whereas that of among staff nurses was 16% and increased by employment up to 3-5 years. Almost half of the student nurse smokers started the habit before admission to higher education facilities, and more than half of staff smokers also started smoking in their school years, in high school or college. Nicotine dependence, as defined by over 11 cigarettes per day and the first cigarette within 30 min after getting up, was high in smokers who started smoking before admission to college or university, but not in those who took up the habit thereafter. Thirty-six percent of student nurses and 25% of staff nurses agreed with the statement that "nurses should not smoke." Only 12% of staff nurses were involved in anti-tobacco interventions routinely, partly due to lack of broad knowledge and the necessary skills. Greater efforts are needed as a high priority to educate student and staff nurses systematically and comprehensively about the range of tobacco interventions available in Japan. 相似文献
996.
997.
998.
999.
Etiopathogenesis and aggravating factors in ulcerative colitis 总被引:2,自引:0,他引:2
Ulcerative colitis (UC) is a chronic inflammatory disease limited to the colon. Although the pathogenesis of inflammatory bowel disease (IBD) remains unclear, several studies have suggested that the onset and development of IBD require the interaction between genetic susceptibility, stimulation by luminal bacterial antigens and adjuvants, and episodic environmental triggers which break the mucosal barrier. There are many reports that experimental enterocolitis in animals does not occur in a sterile (germ free) environment and is prevented by antibiotics therapy. Moreover, patients with UC exhibit pathological immune responses to many commensal enteric bacterial species. Recent data showed that certain probiotic species decrease relapse of UC. These findings suggest that the most possible cause of UC is associated with chronic intestinal inflammation which is induced and perpetuated by non-pathogenic bacteria in genetically susceptible hosts. 相似文献
1000.