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1.
OBJECTIVE: We examined the clinical characteristics of ulcerative colitis patients who demonstrated endoscopically discontinuous lesions at the mouth of the appendix. METHODS: Of patients with initial or recurrent active ulcerative colitis who underwent total colonoscopy during the past 3 yr at Osaka City General Hospital, we selected those who had skip lesions in the mouth of the appendix before treatment, and examined their gender, age, disease type, sites of lesions, inflammatory reaction, severity of disease, effects of treatment, and posttreatment course. RESULTS: Discontinuous lesions at the mouth of the appendix were found in 10 patients, who had the following common clinical features: the major lesion was usually present in the lower part of the large bowel including the rectum, many of the patients had suffered an initial attack only, all patients had mild disease, and many of the patients responded quite satisfactorily to treatment with salicylazosulfapyridine. CONCLUSION: Numerous patients with ulcerative colitis with discontinuous lesions at the mouth of the appendix were observed and their clinical characteristics were examined. Determination of the clinical significance of skip lesions in the appendix will contribute to elucidation of the pathogenesis of ulcerative colitis.  相似文献   
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3.
The direct contact melting of a porous material is investigated experimentally and analytically. The phase change material (PCM) is made of fine ice particles of a nearly uniform diameter, which is changed as a parameter. In the analysis, two models are proposed. One is calculated as the direct contact melting of a monolithic sample and another is treated as an assembly of the direct contact melting of the individual particles. As a result, it was found that the heat flux increased with the diameter, due to increase of permeability in a case of small diameter. But, in a case of large diameter, the heat flux decreased as the particle diameter increased because the direct contact melting occurred independently for the individual particles.  相似文献   
4.
A 3-year child presented with episodic lower abdominal pain; during the eighth attack, a mass was palpable in the left upper quadrant, and a barium enema revealed a stenotic area in the transverse colon. This was resected and an uneventful postoperative course followed. Subsequently, the child has remained symptom-free. instruments are no longer in use.  相似文献   
5.
Humidity Sensor Characteristics of Woodceramics   总被引:9,自引:0,他引:9  
The humidity sensor characteristics of Woodceramics were investigated. The Woodceramics used in this experiment were prepared at 650–900°C. The size of specimens selected was 1 × 1 × 10 mm . One was used as-cut and the other was polished. Above 700°C, the resistance of the specimen was below 50 and the decrease of resistance with increasing relative humidity was small. The specimen prepared at 650°C had a resistance of about 1 k. The resistance of as-cut specimens decreased with increase in relative humidity, but that of the polished specimen did not change significantly. The difference between as-cut and polished samples was explained by the differences in surface micro-structure.  相似文献   
6.
This study was undertaken to estimate the effect of dietary high oleic acid oil (OA) on 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced lung tumorigenesis in mice. Diet containing 10% oil was fed to mice through experimental periods. On day 30 after NNK injection (100 mg/kg body weight, i.p.), the treatment increased the level of prostaglandin E2 (PGE2) as well as proliferating cell nuclear antigen, a marker of cell proliferation in a high linoleic acid oil (LA)-fed group but not in an OA-fed group. The NNK treatment also induced the activation of an extracellular signal-regulated kinase (Erk) cascade (Erk, Mek and Raf-1) in an LA-fed group. On the other hand, OA feeding abolished the NNK-induced activation of the Erk cascade. In conjugation with these events, OA feeding reduced lung tumor incidence and tumor multiplicity (percentage of mice with tumors) in mice compared with LA feeding at the 20th experimental week. These results suggest that OA suppresses lung tumorigenesis and that this suppression is correlated with the inhibition of PGE2 production and inactivation of the Erk cascade.  相似文献   
7.
智能机器人是当今机器人研究的热点,并逐渐由制造领域向非制造领域发展。本文以几种国内外近年研制的新型球类运动机器人为例,介绍了计算机视觉在智能机器人研究中的应用情况。另外,有关人与机器人之间的视觉行为理解研究是计算机视觉研究与智能机器人研究领域的新发展,本文对此也进行了介绍。  相似文献   
8.
The combustion characteristics of high burn rate azide polymer composite propellant were examined by using a chimney type strand burner, a Ø 80 mm × 140 mm small rocket motor and a L/D = 16 of Ø 70 mm heavy-wall rocket motor. The propellant, BAMO/NMMO copolymer was used as a fuel binder and AP as an oxidizer, burned approximately 29 mm/s at a pressure range of 7 MPa to 20 MPa with a plateau-mesa burning behavior. However, the pressure exponent rapidly increased at above the pressure of 20 MPa and was 0.52 between 20 MPa and 25 MPa. The low pressure exponent and high burn rate of the azide polymer propellant are suitable to the short burn time at the maximum expected operating pressure range of 15 MPa to 20 MPa. The high L/D heavywall rocket motor with volumeric mass fraction of 83% showed stable combustion without any pressure oscillation and severe erosive burning. The average burn rate in the high L/D motor was 10% larger than that estimated from the strand data. The theoretically calculated pressure-vs-time and thrust-vs-time curves were well consistent with the measured data. α = 20 and β = 180 for the Lenoir-Robillard equation were used to estimate the burn rate.  相似文献   
9.
The electron transport capability of 4,4′-bis[N-(1-napthyl)-N-phenyl-amino] biphenyl (α-NPD) was investigated by fundamental physical measurements named as current–voltage (I–V) electrical property evaluation and displacement current measurement (DCM). In electron-dominated devices, the I–V characteristics of α-NPD were similar as that of (8-hydroxyquinolino) aluminum (Alq3) owing to their same order of electron mobilities. The interface of Al/LiF and α-NPD was proven to be an Ohmic contact through the evaluation of I–V characteristics at low bias regime (<3 V). And an electron injection barrier, 0.21 eV, at Al/LiF/α-NPD was obtained by extrapolating the temperature dependent I–V curves. The electron transport behavior in α-NPD film was further confirmed by DCM evaluations. Furthermore, an efficient white organic light emission device was successfully fabricated by using α-NPD as hole transport layer and electron transport layer, respectively.  相似文献   
10.
Aluminium (Al) was detected in semi-thin sections of three organs, the duodenum, liver and kidney, of ddY strain mouse by energy dispersive X-ray microanalysis at high accelerating voltages around 300 kV. Firstly, to determine the conditions best for detecting Al, several adult ddY mice were injected intraperitoneally with aluminium chloride (AlCl3) and the duodenums were fixed, embedded and sectioned at various thicknesses and subjected to energy dispersive X-ray microanalysis at various accelerating voltages from 100 to 400 kV. From the results obtained, 1.0 microm-thick sections observed at 300 kV resulted in the highest peak-counts/background ratios and were shown to be the most suitable for X-ray microanalysis. Secondly, ddY mice aged four weeks were administered orally with 2% AlCl3 at pH 2.5 for two weeks and the three organs (duodenum, liver and kidney) were subjected to X-ray microanalysis under the same condition found above. The results were compared with light microscopic Al staining of the same tissues. Aluminium was detected in lysosomes of the three kinds of tissues with higher sensitivity by energy dispersive X-ray microanalysis by light microscopic observation. From the results, it was suggested that Al dissolved in acidic water was absorbed in the duodenum and accumulated in the liver and kidney.  相似文献   
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