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71.
Plasma polymerizations of three kinds of amines, γ-aminopropylethoxydimethylsilane (APEMS), allylamine (AA), and pyrole (PY), were investigated by IR and XPS analysis. Plasma-polymerized films were deposited on porous substrates, and ion exchange abilities of the composite membranes were measured. When APEMS were used as the monomer, the polymer retained the chemical structure of the monomer, amino groups. However, when AA and PY were used as the monomers, the plasma polymers contained a larger amount of amido structures than did the polymer of APEMS. Each membrane had ion exchange ability. In particular, the membrane prepared from APEMS showed superior ion exchange ability, anion permselectivity and conductivity, in acidic solutions. This property was attributed to the chemical structure of the polymer from APEMS retenting amino groups. The ion exchange properties of the membranes depended on the pH of the solution. In particular, the membrane of APEMS showed high membrane potential and low electric resistance only in a narrow pH region due to the weak basicity of amines and the hydrophobic property of the polymer. 相似文献
72.
S Madoiwa K Arai Y Ueda M Ishizuka J Mimuro S Asakura M Matsuda Y Sakata 《Canadian Metallurgical Quarterly》1997,121(2):278-287
Two groups of anti-plasminogen monoclonal antibodies, whose epitope was either in the kringle 1 + 2 + 3 domain (F3P2, F11P5, F11P6, and F12P18) or the kringle 5 domain (F1P6 and F12P16), were isolated and their effects on the conformation of plasminogen were explored. All antibodies except F1P6 had 3- to 10-fold higher affinity toward Lys-plasminogen than Glu-plasminogen. F1P6 exhibited a comparable affinity to Glu- and Lys-plasminogen. Among these, only F11P5 binding was inhibited by epsilon-amino-nu-caproic acid (EACA) in a concentration-dependent manner, with half maximal inhibition at 3 mM. From a competition assay, we concluded that the epitopes of F11P5, F11P6, and F12P18 should be very close, and located at or near the low affinity lysine binding site on the kringle 2 + 3. These three antibodies dramatically enhanced the binding of Glu-plasminogen to the other antibodies, except to F1P6. Interestingly, F3P2, whose non-overlapping epitope was in the kringle 2 + 3 domain, also augmented the binding of Glu-plasminogen to the other antibodies. In contrast, we did not observe enhanced binding of Lys-plasminogen to one antibody in the presence of the other antibodies, and the binding of Glu-plasminogen to these antibodies did not increase in the presence of 10 mM EACA. In the presence of these antibodies, including F1P6, Glu-plasminogen bound more efficiently to immobilized degraded fibrin, with a binding profile similar to Lys-plasminogen. All antibodies except F1P6 enhanced the conversion rate of plasminogen to plasmin remarkably. Taken together, we propose that these two groups of monoclonal antibodies can dissociate the intramolecular interactions of Glu-plasminogen and induce the conformational transition of Glu-plasminogen to Lys-plasminogen. In addition, the kringle 2 + 3 and kringle 5 structures of Glu-plasminogen liganded with EACA are distinct from the Lys-plasminogen structure. 相似文献
73.
A 75-year-old man who worked at a horse racing track, had an abnormal shadow on a chest radiography. He had a history of dilated cardiomyopathy and mitral regurgitation but had not had any respiratory or systemic symptoms for two years. Chest radiographs and CT scans showed slowly increasing consolidation with internal areas of low attenuation, and without cavity formation, at the left S8. The erythrocyte sedimentation rate, C-reactive protein level, WBC count, percentage of eosinophils, and IgE level were 35 mm/hr, negative, 8400, 17%, and 3628 IU/ml, respectively. Eosinophils were found in samples of sputum. His immunological status was normal. Transbronchial lung biopsy yielded necrotic tissue, along with gram-positive and irregular acid-fast branching filaments that grew in culture. The microorganism was identified as Nocardia asteroides. Occupational inhalation of soil may have caused his disease. 相似文献
74.
Physicians and patients need convenient access to quality medical information. This study's goal was to place a medical resource on the World-Wide Web (WWW), allow access to it through a simple to use interface, and analyze the usage of such a resource. The Family Practice Handbook (TFPH) was digitized and placed onto the WWW. Usage data was obtained from June 1995-June 1996. 118,804 individuals accessed TFPH viewing 409,711 pages of information. A broad spectrum of topics was accessed. TFPH proved to be an extremely popular resource, servicing the broad information needs of an international audience. These preliminary findings suggest the future promise of Internet medical resources. 相似文献
75.
76.
Chromatic blur seen along the contours of a figure on a color TV display is not so annoying if the contour luminance signal is sharp. This is due to the human visual property that chromatic blur is masked by the luminance by spatial luminance changes. This paper describes the subjective evaluation of the visual masking effect of chromatic blur depending on luminance signals. From the experiments, the chromatic blur becomes less perceptible with the increase in level of superposed luminance signals and the blur is more annoying in red than in blue or yellow. Highly saturated red figures cause poor picture quality. 相似文献
77.
H Yamamoto K Kuramitsu I Houya H Maruo K Sakata K Tabe I Kimura K Inoue M Shibasaki K Yamamoto Y Sakamoto H Matsuo 《Canadian Metallurgical Quarterly》1996,45(10):1106-1111
To evaluate the significance of peptide leukotrienes (LTC4, D4, E4) in asymptomatic asthmatic patients, we measured urinary LTE4 levels which is thought to reflect in vivo production of peptide LTs. Urinary LTE4, was extracted using C18 solid phase column and measured by radioimmunoassay. There was no significant difference in urinary LTE4 levels among asthmatics with different severity or between atopic and non-atopic asthmatics. Urinary LTE4 levels were significantly elevated in asthmatics compared with normal controls (p < 0.05). When compared with normal controls, urinary LTE4 levels were significantly elevated in moderate to severe asthma (p < 0.05), and non-atopic asthmatics (p < 0.001). Urinary LTE4 levels were significantly elevated in aspirin-sensitive asthmatics compared with aspirin-tolerant asthmatics (p < 0.05). There was no significant difference in urinary LTE4 levels among aspirin-sensitive asthmatics with different severity. These results suggest that increased production of peptide LTs is a characteristic in aspirin-sensitive asthma, and that the severity and type of asthma and the presence of aspirin-sensitive asthma should be taken into consideration in the analysis of urinary LTE4 levels. 相似文献
78.
Y Yamada K Tsushima Y Sakata S Saito T Ito N Sugimoto H Ogasawara Y Tamura N Moriya Y Komatsu 《Canadian Metallurgical Quarterly》1994,21(7):1029-1032
Forty-two patients with gastric cancer were entered in this study. Forty-one of them were eligible and administered sequential methotrexate (MTX)/5-fluorouracil (5-FU) with 5'-deoxy-5-fluorouridine (5'-DFUR). 5-FU was administered intravenously by drip infusion for 2 hours in 22 cases (group A), and was infused by bolus injection in 19 cases (group B). The treatment schedules were as follows: MTX 100 mg/m2 was given intravenously (i.v.) followed by 5-FU 600 mg/m2 i.v. 2 hours later and leucovorin 15 mg/body i.v. 8 and 20 hours later. This cycle was repeated once a week. 5'-DFUR 1,200 mg/body/day was given orally on 5 consecutive days per week. Three of 20 cases (15%) in group A showed PR, while 5 of 15 cases (33%) in group B showed PR. Median survival time was 2.8 months in group A and 3.7 months in group B. There was, however, no statistical difference. Gastrointestinal toxicity was commonly observed. Leukocytopenia was more severe in group B. Alopecia was more frequently observed in group B (p < 0.025). These results suggested bolus injection of 5-FU was a promising way of administration in sequential MTX/5-FU therapy. 相似文献
79.
Piezoelectric and ferroelectric properties of bismuth sodium titanate, (Bi1/2Na1/2)TiO3(BNT)-based solid solution, that is, (Bi1/2Na1/2)(1-x)(Pba Bab)xTiO3(a + b = 1) [BNPB(100x-100a/100b)], are studied from the viewpoint of a new group of lead-free or low-lead content piezo-electric ceramics with a rhombohedral(Fa-tetragonal (Fβ) morphotropic phase boundary (MPB). It is evident that the MPB seems to be remarkably efficacious in promoting piezoelectric and pyroelectric activities by electrical poling. X-ray diffraction data, dielectric properties and D-E hysteresis loops show that the MPB exist near (Bi1/2Na1/2)TiO3[BNT] at x = 0.13–0.14, 0.08–0.09 and 0.06–0.07 in the case of b = 0, b = 0.5 and b = 1, respectively. BNPB ceramics are superior for piezoelectric ceramics in high-frequency ultrasonic uses, or special piezoelectric actuator materials with a lower free permittivity ε33Tε0, and a high electromechanical coupling factor k33, along with a high mechanical strength. 相似文献
80.
Two new alcoholic aroma precursors, cis- and trans-linalool, 3,7-oxides 6-O-beta-D-apiofuranosyl-beta-D-glucopyranosides (1 and 2), as well as two already known compounds, (Z)-3-hexenyl beta-D-glucopyranoside (3) and methyl salicylate 6-O-beta-D-xylopyranosyl-beta-D-glucopyranoside (beta-primeveroside: 4), and another new monoterpendiol glycoside, 8-hydroxygeranyl beta-primeveroside (5) have recently been isolated as aroma precursors in tea leaves (Camellia sinensis var. sinensis cv. Maoxie) ready for oolong tea processing. 相似文献