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Summary A direct immunohistochemical method of high specificity is presented for the demonstration of sites of cathepsin B1. Antisera were raised in rabbits against pure enzyme preparations. The specific antibodies were subsequently isolated and labelled according to methods previously published. Sections from tissues specially rich in this enzyme like liver, kidney, intestinal epithelia and the active macrophages of talcum granulomas were studied. The results suggest a localization of this enzyme mainly to lysosomal organelles and phagocytic vacuoles, which are known from chemical data to contain this enzyme. The prerequisite for a positive tissue reaction is that the enzyme must be present in a form available for antigen-antibody interaction. 相似文献
914.
Bernard Longpré Prométéo Madarnas Léo Cousineau Marcel Rochon Serge Filion 《CMAJ》1974,110(6):645-648
Scleronodular type of Hodgkin''s disease: experience at the Centre hospitalier universitaire de SherbrookeThe nodular sclerosis type of Hodgkin''s disease appears to be a distinct clinical entity. However, the incidence, the initial localization of the tumour and the survival of the patients are variable. The present study was carried out on a group of 17 patients, all French Canadians living in the province of Quebec, from a total of 31 with Hodgkin''s disease, an incidence of 55%. There were more males (10) than females (7). The mean age of the group was 37 years, but that of the females was lower than that of the males. The mediastinum was involved at the onset in 47% of the patients. The initial staging (according to the classification of Rye) in 76% of the patients was I or II.Four patients showed disease below the diaphragm. The lungs were infiltrated three times, the spleen six times, and the liver five times. The duration of survival of the 17 patients was twice that of the patients with the three other types of the disease. 相似文献
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917.
The partial purification and characterization of cytosol alcohol dehydrogenase from Astasia 下载免费PDF全文
1. The cytosol alcohol dehydrogenase (alcohol-NAD oxidoreductase, EC 1.1.1.1) of Astasia longa was partially purified and characterized from cells grown in the presence of air+CO(2) (95:5) or of O(2)+CO(2) (95:5). 2. Under both these growth conditions, the cells contained a fraction, ADHII, which was characterized by its electrophoretic properties, by a high degree of resistance to heat inactivation, by a sharp pH optimum at 8.2 and by its kinetic properties. The estimated molecular weight of this fraction was approx. 150000, which is similar to that of yeast alcohol dehydrogenase. 3. Cells grown in air+CO(2) (95:5) contain another fraction, ADHI, which can be further separated into two subfractions by polyacrylamide-gel electrophoresis and by DEAE-cellulose chromatography. This was termed fraction ;ADHI-air'. 4. In addition to fraction ADHII, cells grown in the presence of O(2) have a twofold increase in fraction ADHI-air activity as well as two new fractions that could not be demonstrated in air-grown cells. These new fractions which we have called fraction ;ADHI-O(2)', account for about 10% of the total activity. 5. The ADHI fractions (air) and (O(2)) have similar broad pH-activity curves and similar kinetic properties, both having a lower K(m) for ethanol and NAD than fraction ADHII. However, they differ from each other with respect to their activity with various substrates. The estimated molecular weight of these two ADHI fractions and their chromatographic behaviour on hydroxyapatite and on DEAE-cellulose also distinguish them. 相似文献
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Pulsed NMR spectroscopy has been used to study Na+ binding to several simple carbohydrates in aqueous solution. Changes in the 23Na spin-lattice relaxation time (T1) were monitored to indicate complex formation between sodium ions and a ligand. It was found that Na+ interacts with these hydroxy-compounds in a manner similar to other metal cations, but very weakly. Among the sugars investigated, -inositol forms the strongest complexes with the stability constant about 1.2 M?1 (if 1:1 complexes are assumed). A qualitative study of competition between Na+ and Ca2+ was done, indicating that both cations have the same binding sites. 相似文献
920.