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951.
952.
This tutorial paper considers a 1-unit repairable system which operates at discrete times. Some appropriate results for the system are rewritten as discrete time processes. After introducing costs this paper discusses optimum preventive maintenance policies which minimize the s-expected cost. 相似文献
953.
Toshiaki Aoai Akira Umehara Akihiko Kamiya Nobuaki Matsuda Yoshimasa Aotani 《Polymer Engineering and Science》1989,29(13):887-890
A new positive-working photosensitive system of silicon polymer, containing silylether groups in the main chain and a photo-induced acid precursor was investigated. The silicon polymer is hydrolized by a photogenerated acid and degraded to low molecular weight compounds. Thus the effect of solubility inhibition of the polymer is diminished. The higher photosensitivity of this system as compared with 1,2-quinone diazide compounds is due to the catalytic reaction of the acid on the hydrolysis of the silicon polymer. The chemical structure around silylether groups in the polymer, in particular more hydrophilic and less steric structures, affects the rate of hydrolysis and thus the photosensitivity. Among various types of photo-induced acid precursors examined, e.g., s-triazine and 1,3,4-oxadiazole compounds substituted by trihalomethyl groups were effective. 相似文献
954.
N Babaya H Ikegami Y Kawaguchi T Fujisawa Y Nakagawa Y Hamada M Hotta H Ueda M Shintani K Nojima Y Kawabata M Ono K Yamada GQ Shen M Fukuda T Ogihara 《Canadian Metallurgical Quarterly》1998,35(3):150-153
Since natural proteins are the products of a long evolutionary process, the structural properties of present-day proteins should depend not only on physico-chemical constraints, but also on evolutionary constraints. Here we propose a model for protein evolution, in which membranes play a key role as a scaffold for supporting the gradual evolution from flexible polypeptides to well-folded proteins. We suggest that the folding process of present-day globular proteins is a relic of this putative evolutionary process. To test the hypothesis that membranes once acted as a cradle for the folding of globular proteins, extensive research on membrane proteins and the interactions of globular proteins with membranes will be required. 相似文献
955.
Calcium channel blocker (CCB) is one of the most frequently prescribed cardiovascular drugs. Two main classes of CCBs, dihydropyridines and benzothiazepines, are now clinically available for the treatment of hypertension in Japan. Both drugs inhibit the inward current of calcium ions through the L-type calcium channels. However CCBs have markedly different chemical structures and different effects on cardiovascular system. Therefore, in the present paper, their pharmacokinetic properties and interactions with other drugs are reviewed, and newly developed CCB are also described. 相似文献
956.
S Asano H Murayama Y Okada T Sezaki Y Nakagawa K Tatsuno 《Canadian Metallurgical Quarterly》1998,46(11):1172-1176
The rise of minimally invasive surgical techniques during the past 20 years has been one of the more dramatic developments in modern medicine. Minimally invasive procedures are now widely accepted for treatment of diseases involving many different organ systems. Minimally invasive procedures may be more common and more accepted in the treatment of diseases of the biliary tract than in any other area. The development of laparoscopic cholecystectomy serves as a benchmark for minimally invasive procedures, and it is now the standard of care for the treatment of cholelithiasis. Today, not only is laparoscopic cholecystectomy one of the most common operations performed in the United States, but many new techniques have been developed that allow minimally invasive treatment of a variety of biliary tract diseases. The development of nonoperative techniques for treatment of biliary tract disease has accompanied the rapid developments in minimally invasive surgical techniques. This article describes the nonoperative treatment of biliary tract disease. 相似文献
957.
M Hyogo A Azuma M Tsukamoto K Yamamoto T Yamamoto K Kawata M Nakagawa H Miyazaki Y Kono M Miyagawa T Ebisawa K Furukawa 《Canadian Metallurgical Quarterly》1998,32(6):363-370
The plastic qualities and vascular reliability of the frontal flap have been widely used for reconstruction of facial tissue. We revised the files of 105 patients who had undergone surgical repair of facial tissue loss with frontal flaps. The epidemiology, etiology of the repaired tissue loss and indications for frontal flap as well as the various techniques were analyzed: 66.7% of the patients were over 60 years of age; 74% had ambulatory surgical repair; 54.4% of the repaired tissue losses were situated in the nasal region; 80% of the losses were due to tumoral formations. The median flap was the most widely used (23.2%). 相似文献
958.
K Ohtsuki H Sugihara Y Taniguchi I Umamoto T Nakagawa T Nakamura A Azuma Y Kohno H Adachi M Ochiai 《Canadian Metallurgical Quarterly》1994,31(4):309-318
Hypertrophic cardiomyopathy (HCM) is known to have the impairment of myocardial perfusion as well as irregularly hypertrophic myocardium. To evaluate myocardial perfusion and ventricular shape in HCM, 99mTc-Tetrofosmin scintigraphy was performed after exercise (Ex) and at resting state (Re) in 10 patients with HCM and was compared with early image (Ea) and delayed image (De) of 201Tl scintigraphy performed after exercise. SPECT images of both 99mTc-Tetrofosmin and 201Tl scintigraphy were analyzed with five scaled visual scores set in 18 segments. The complete concordance ratio between 99mTc-Tetrofosmin (Ex and Re) and 201Tl (Ea and De) images in segmental analysis was 75%. Image quality of 99mTc-Tetrofosmin was seemed to be superior to that of 201Tl scintigraphy. In 9 patients with HCM, 99mTc-Tetrofosmin scintigraphy was performed under the ECG gating and the thickness of septal and free wall was measured. Good correlation was observed with the data by ultrasound cardiography (r = 0.79, p < 0.002 in wall thickness, r = 0.84, p < 0.01 in the ratio of septal wall thickness to free wall thickness). Left ventricular shape (ventricular long axis) was closely resemble to that of left ventriculography by contrast medium. In conclusion, 99mTc-Tetrofosmin scintigraphy is useful for the evaluation of myocardial morphology as well as perfusion abnormality. 相似文献
959.
Infectious peritonitis is a common complication of continuous ambulatory peritoneal dialysis (CAPD). Only one case of CAPD-related peritonitis due to Penicillium sp has previously been reported. We present a second case in which fungal colonies were observed on the inner surface of the CAPD catheter. The infection was successfully treated with catheter removal and intravenous amphotericin B. 相似文献
960.
Aoyagi M. Hamazaki Y. Nakagawa H. Kurosawa I. Maezawa M. Takada S. 《Applied Superconductivity, IEEE Transactions on》1994,4(3):169-176
A chip layout design technique for a high-speed Josephson LSI circuit using an automatic placement and routing technique with a standard cell method has been developed. A chip layout design of a Josephson LSI circuit with 1500 gates for examining high-speed operability with a 1 GHz clock frequency has been successfully obtained. Related to high-frequency power on a high-speed Josephson LSI circuit, a dividing method for a circuit and a balancing method for power loads are proposed 相似文献