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71.
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Tatsuo Yamamura Masaki Arashima Kazumi Nakatani Takafumi Ishida Fukiko Yamada Tomihiro Nishiyama 《Journal of the American Oil Chemists' Society》1995,72(4):497-500
The antioxidant activities of 9H-xanthene-2,7-diols and α-tocopherol were studied during the oxidation of linoleic acid in a homogeneous solution and in an
aqueous micelle dispersion. The antioxidant activities of 9H-xanthene-2,7-diols for both systems were 1.0–2.4 times greater relative to α-tocopherol. In addition, the 1,3,4,5,6,8-hexamethylxanthene-2,7-diol
showed less cytotoxicity toward human fibroblasts than did 2,6-di-t-butyl-4-methylphenol. 相似文献
74.
75.
K. Mitsui T. Aoki A. Okada Y. Ohashi Y. Muraki S. Shibata I. Nakamura H. Kojima T. Kitamura Y. Minorikawa Y. Kato T. Takahashi S. Higashi K. Kobayakawa Y. Kamiya 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1990,290(2-3):565-578
Accurate measurements of the total number of muons in an air shower are important for the discrimination of showers produced by astronomical gamma rays from those produced by protons. In order to perform this discrimination, muon detectors with a total area of about 400 m2 have been constructed in the Ohya stone mine. At ground level, scintillation detectors have been distributed for determining the total number of electrons in the air shower. The arrival direction of the air shower determined by usual timing information was examined using independent data on the arrival direction determined by muons in the shower. The angular resolution thus obtained at the shower maximum is 1.7° in the south-north plane and 2° in the east-west plane. The difference of the resolution is due to the asymmetric arrangement of scintillation detectors. 相似文献
76.
S Iwata N Sakuma T Hibino T Sato A Yoneyama Y Kamiya M Kawaguchi T Fujinami M Kunimatsu 《Canadian Metallurgical Quarterly》1995,28(3):309-311
Results 2 1/2 years after an enuresis nocturna training are presented, including rate of success, percentage and duration of relapse for 113 children (mean age 11.6 year at the start of the training). The bibliotherapeutic treatment by parents did not require any intervention by a professional. Behaviour of parents in the event of a relapse differed between training conditions. Children in the Arousal condition recovered faster from a relapse, 90% of their parents used the Arousal training again at relapse or did not intervene at all and none of them consulted a professional. Clearly they had confidence in the method of Arousal training: combining the alarm device with reinforcement for correct behaviour at the time the alarm goes off. Parents in control conditions did not use the alarm device as often as the parents in the Arousal condition, but tried other means with less success, including consulting professionals. 相似文献
77.
Influence of Slurry Flocculation on the Character and Compaction of Spray-Dried Silicon Nitride Granules 总被引:1,自引:0,他引:1
Hideo Takahashi Nobuhiro Shinohara Masataro Okumiya Keizo Uematsu Tsubaki JunIchiro Yuji Iwamoto Hidehiro Kamiya 《Journal of the American Ceramic Society》1995,78(4):903-908
The effect of slurry flocculation on the characteristics of silicon nitride granules prepared by the spray drying process is investigated. The flocculation state of an aqueous silicon nitride slurry is controlled by adding nitric acid and evaluated as a function of pH. Dense and hard silicon nitride granules result from a well-dispersed slurry having a high pH (e.g., 10.8). These hard granules retain their shape in green compacts and form detrimental defects. Lowering the pH of the slurry to a certain value (e.g., pH 7.9) results in slurry flocculation. Granules prepared from this flocculated slurry have low density and low diametral compression strength and contribute to the elimination of large pores in green compacts. 相似文献
78.
Lee J. Tanaka T. Sasaki S. Uchiyama S. Tsuchiya M. Kamiya T. 《Lightwave Technology, Journal of》1998,16(5):884-891
A novel design procedure of broad-band multilayer antireflection (AR) coatings for optical and optoelectronic devices is proposed. The design algorithm is based on the optical admittance detuning, with the bandwidth of finite reflectivity as a new merit function. Coating structures consist of only two materials with nonquarter-wave thicknesses. Numerical mappings on the four-layer structure showed four optimizing regions where an optimized four-layer AR coating on 1.55 μm GaInAs-AlGaInAs MQW semiconductor laser facet was predicted to have a broad bandwidth of 106 mm for a reflectivity of less than 10-5. TiO2 and SiO2 were electron-beam (EB) evaporated to form the four-layer AR coating on glass and InP substrates with an ion-beam assist and a real time in situ optical thickness monitor and experimentally verify its broad-band performance 相似文献
79.
OBJECTIVE: Oesophagectomies have a high morbidity rate, mainly related to pulmonary complications. The aim of this work was to assess whether the thoracoscopic approach could reduce this morbidity. PATIENTS AND METHODS: We conducted a prospective study of the results of 26 attempts of esophagectomy using a right thoracoscopic approach. There were 17 males and 9 females having an average age of 47. The indication was a squamous cell carcinoma in 19 patients, an adenocarcinoma in 1 patient, a melanoma in 1 patient and a caustic stenosis in 5. The whole oesophagus was mobilized thoracoscopically, and the eosophagectomy was completed through the abdomen. The reconstruction was achieved using a gastric pull-through and a cervical anastomosis. RESULTS: There were 5 failures for the following reasons: unresectable carcinoma (1 case), large tumour making a thoracoscopic dissection unsafe (1 case) and incomplete lung collapse making the exposure of the posterior mediastinum difficult (2 cases). The average time of the thoracoscopic procedure was 135 min. The post-operative course was uneventful in all but 5 patients who had a pulmonary complication: atelectasis (3 cases), right purulent pleural effusion (1 case), acute respiratory distress syndrome (1 case). The latter complication was lethal. Four out of 5 respiratory complications occurred in patients for whom the dissection was considered as difficult. Among the other complications, there were 5 anastomotic leakages and 3 laryngeal nerve palsy. The mortality rate was 3.8%. CONCLUSION: These initial results do not show a real benefit of the thoracoscopic approach for eosophageal dissection, especially for difficult oesophagectomies. Further evaluation of the technique is needed. 相似文献
80.
Earlier studies in our laboratories demonstrated that particles of a number of snack foods that are retained on the dentition accumulate fermentable sugars and short-chain carboxylic acids (SCCA; acetic, formic, lactic, and propionic) to different degrees. The present study was undertaken to test the hypothesis that the accumulated SCCA can induce a gingival inflammatory response. Five periodontally and medically healthy subjects were given portions of plain doughnuts (high SCCA levels) or oatmeal cookie (low SCCA), or had the SCCA applied directly to the gingival margins of designated teeth. Subjects were given wax to chew, or nothing, as controls. Inflammation was assessed by measurements of subgingival temperature, flow rates of gingival crevicular fluid (GCF), and neutrophil emigration into GCF. Subgingival temperatures of the maxillary gingiva rose by 1.32 +/- 0.30 degrees C (mean +/- SE) 5 min after the subjects consumed the doughnuts and remained elevated for at least 1 hr. These values were significantly higher than those obtained from subjects after ingestion of oatmeal cookies (0.63 +/- 0.17 degree C; p < 0.01), consistent with the low levels of SCCA in the retained cookie particles. Wax chewing elicited a similar response, indicating a masticatory effect on the gingiva. Gingival temperatures in the unchallenged controls remained unchanged. Neutrophil emigration into the GCF was significantly elevated in subjects after doughnut consumption. Rinses with a solution of SCCA, or application of the SCCA to the gingiva, also brought about significant elevations in subgingival temperature and neutrophil emigration. The findings describe the inflammatory effects of food ingestion on the gingiva of healthy human subjects, and support the hypothesis that SCCA in the particles of retained food are at least partly responsible for the observed responses. 相似文献