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71.
OBJECTIVE: To investigate the expression of sialosyl-Tn antigen (STn) in human benign and malignant prostate. MATERIALS AND METHODS: The expression of STn was investigated immunohistochemically in formalin-fixed and paraffin-embedded tissue specimens from 56 patients with primary prostatic adenocarcinoma (median age 74.3 years, range 47-89) and 20 patients with benign prostatic hyperplasia (median age 73.4 years, range 60-87). RESULTS: STn was expressed in only three (4%) of the 20 hyperplastic glands and the benign areas adjacent to the 54 carcinomas; by contrast, STn was expressed in 34 (61%) of the 56 carcinomas. The frequency of STn positivity was much higher in well-differentiated carcinomas than in those poorly differentiated. CONCLUSION: STn is expressed with malignant transformation of the prostatic epithelial cells and immunohistochemical methods using commercially available STn monoclonal antibody may be useful as an adjunct for distinguishing carcinoma from benign tissue.  相似文献   
72.
Summary Considerable improvements were made to the original Rankine method. Replacement of aspiration with an injection system contributed a great deal to the simplification of procedure, being accompanied with an increase in reproducibility. Air (flow rate 1.01/min) was used for injection because the use of inert gas gave little increase in recovery rate.Sodium bisulphite (free sulphite) and three kinds of combined sulphite compound (bisulphite adducts of acetaldehyde, pyruvic acid and D-mannose) were used to find the most suitable conditions for the separate determination of free and combine sulphites.Free sulphite was expelled from the sample by bubbling at 0 °C for 30 min. It was confirmed that no combined sulphite was dissociated under these conditions. The phosphoric acid concentration had an important role in the liberation of sulphite. When 25% phosphoric acid was used, more than 99% of free sulphite was expelled by cold bubbling and more than 99% of combined sulphite was recovered by heating afterwards for 10 min.The scope of the modified Rankine method was also extended to the determination of sulphite in concentrated orange juice.
Verwendung der modifizierten Rankine-Methode zur getrennten Bestimmung von Sulfiten in Lebensmitteln. III
Zusammenfassung Die Rankine-Methode wurde bedeutend verbessert. Ein Umtausch der Aspiration mit Blasensystem trug beträchtlich zur Vereinfachung des Bestimmungsverfahrens bei, und die Reproduzierbarkeit wurde verbessert. Luft (Fließrate 1,01/min) wurde als Blasengas benutzt, da der Gebrauch von Inertgas für die Wiederfindungsrate unbedeutend ist.Natriumhydrogensulfit (freies Sulfit) und drei Arten gebundener Sulfite (Acetaldehydhydrogensulfit, Pyruvathydrogensulfit undd-Mannosehydrogensulfit) dienten dazu, die geeignetsten Bedingungen für die getrennte Bestimmung der freien und gebundenen Sulfite zu ermitteln.Freies Sulfit wurde bei 0 °C durch 30 min Durchblasen vertrieben. Hierbei ging kein gebundenes Sulîit verloren. Die Phosphorsäurekonzentration war wichtig für die Freisetzung des Sulfites. Wenn man 25%ige Phosphorsäure verwendet, werden > 99% freien Sulfites beim Durchblasen in der Kälte vertrieben, während > 99% gebundenen Sulfites durch nachheriges 10 min langes Erhitzen wiedergewonnen werden.Die modifizierte Rankine-Methode wurde weiterhin für konzentrierte Säfte verwendet.


Studies on the Analyses of Sulphites in Foods (III)  相似文献   
73.
Adriamycin hydrochloride was microencapsulated with ethylcellulose by a phase separation method to develop a prolonged release dosage form. Polyisobutylene (PIB) was used as a coacervation-inducing agent to control the particle size and drug release rate of the resultant microcapsules. With increasing the concentration of PIB (1 to 3 %) the average diameter of the microcapsules decreased, due to the fact that the microcapsules were discreted to a single microcapsule. At low concentration of PIB, the resultant microcapsules were agglomerated, which resulted in increasing the size. The microcapsules prepared with PIB 2 % prolonged desirably the drug release from the microcapsules. A little size effects of the microcapsules on the drug release rate was found for the microcapsules with PIB 2 % and 3 %.  相似文献   
74.
The endoplasmic reticulum (ER) resident protein, ER60, is a member of the protein disulfide-isomerase family and contains two copies of the internal thioredoxin motif, CGHC. Previously, ER60 was identified as a cysteine protease and named ER-60 protease (Urade, R., Nasu, M., Moriyama, T., Wada, K., and Kito, M. (1992) J. Biol. Chem. 267, 15152-15159; Urade, R., and Kito, M. (1992) FEBS Lett. 312, 83-86). Here, ERp72, the other member of the protein disulfide-isomerase family containing three CGHC motifs, was isolated from ER of rat and mouse livers through four sequential chromatographies on DEAE-Toyopearl 650, AF-heparin Toyopearl 650M, and TSK gel G3000SW twice. The purified rat protein was found to be homogeneous on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, not being contaminated by ER-60 protease, as judged on immunoblot analysis using an anti-ER-60 protease antibody. The partial amino acid sequence of rat ERp72 was 93% homologous to that of mouse ERp72. The purified rat ERp72 degraded other ER resident proteins such as protein disulfide-isomerase and calreticulin. The purified mouse ERp72 also degraded those proteins. Though rat ERp72 did not basically require Ca2+ for the reaction, the degradation of protein disulfide-isomerase was enhanced, but the degradation of calreticulin was inhibited in the presence of Ca2+. The proteolytic activity of rat ERp72 was inhibited by cysteine protease inhibitors. Its sensitivity to protease inhibitors was the same as that of ER-60 protease. In addition, the proteolytic activity of rat ERp72 was inhibited by acidic phospholipids, also similar to ER-60 protease. Therefore, we propose that ERp72 be named ER-72 protease.  相似文献   
75.
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   
76.
Pathogenic effect of the crystalline exotoxine of Bacillus thuringiensis on the larvae of fleas was investigated. Deformities and changes in the functions of organs and tissues caused by the exotoxin in larvae and imago developed from the latter result in the premature death of the individuals (to 100%) or in the sterility of the remaining fleas.  相似文献   
77.
78.
Sulfamethoxazole microcapsules with polysaccharide gum, i.e. xanthan gum and guar gum, were prepared by employing a spray drying technique. The aqueous or the ammonium hydroxide solution of the gum containing the drug with or without colloidal silica was atomized with a centrifugal wheel atomizer rotated at 40000 rpm into a drying chamber held at 140±10°C. By formulation with colloidal silica, particle size of the resultant product increased, leading to improve the flowability and packability for the tableting. Polymorphic sulfamethoxazole mixture of Form I, II and III was produced in the formulation with cellulose acetate  相似文献   
79.
Reflection measurements in the 25-35 nm region were made for Mg/SiC and Mg/Y2O3 multilayers kept in a low-humidity atmosphere for 4 or 5 years. Aged Mg/SiC multilayers keep their reflectances, and the reflectance value at 31.2 nm is 0.44 at 10 degrees of the normal angle of incidence. Aged Mg/Y2O3 multilayers change reflectance as top layer materials, and the best value at 30.1 nm is 0.40 at 10 degrees. Reflection measurements are also made for Mg-based multilayers that are annealed from room temperature to 400 degrees C at 50 degrees C intervals. Both multilayers keep their reflectance at annealing temperatures of 200 degrees C. These results suggest that both Mg-based multilayers can be applied to practical optics.  相似文献   
80.
The experimental attempt to investigate hot electron distribution was made on the basis of field-dependent photoluminescence spectrum and the result was elaborately compared with Monte Carlo calculation. The photoluminescence spectrum due to band-to-acceptor or band-to-band transition in GaAs and Ga1?xAlxAs was measured under electric fields. The spectral change in GaAs is interpreted as a deformation from the Maxwellian distribution in comparison with the theoretical results. Hot electron distribution in Ga1?xAlxAs with a small energy separation was also investigated using the three valley model.  相似文献   
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