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71.
Keratinolytic proteinase produced by Candida albicans   总被引:11,自引:0,他引:11  
M Hattori  K Yoshiura  M Negi  H Ogawa 《Sabouraudia》1984,22(3):175-183
Candida albicans was cultivated in various media that contained human stratum corneum, human scalp hair or keratin powder (cow's hoof) as a nitrogen source. Production of a keratinolytic proteinase (KPase) was observed when C. albicans was incubated in the medium containing stratum corneum. However, there was no production of a KPase that could digest human stratum corneum in the medium containing hair or keratin powder. alpha-fibrous protein extracted from human stratum corneum was digested by the KPase. The pH optimum of the enzyme was 4.0 and enzyme activity was inhibited by pepstatin A and chymostatin. The KPase, a kind of carboxyl proteinase, may be important for C. albicans to enable it to play a pathogenic role in vivo.  相似文献   
72.
Summary The usefulness of LMS in postoperative immunochemotherapy of gastric cancer was investigated. In compliance with the protocol, MMC was given at a dose of 20 mg on the day of gastrectomy, and an additional 10 mg on the next day IV. The patients receiving 600 mg Tegafur daily were then divided into two groups according to whether LMS was also given or not. LMS was administered for 3 days before the operation in a daily dose of 150 mg and for 1 year or more after operation according to a schedule of 3 days' administration followed by an 11-day interval. The 2-year follow-up demonstrated that in stage III patients, the LMS (+) regimen was superior to the LMS (–) regimen, since the former prolonged the relapse-free interval significantly. The survival rate for stage III disease was also significantly higher in the LMS (+) than in the LMS (–) group. There was no significant difference in the incidence of subjective or objective side-effects between two groups. The incidence of agranulocytosis was comparable in the two groups.Gastrointestinal Cancer Research Group, Japan Levamisole Research AssociationChairmen of the Gastrointestinal Cancer Research Group, Japan LMS Research AssociationController of the Gastrointestinal Cancer Research Group, Japan LMS Research AssociationMembers of the Data Collection and Analysis SubcommitteeThis study was carried out by the Gastrointestinal Cancer Research Group, Japan LMS Research Association (directed by Prof. Kiyoshi Inokuchi, Dept. of Surgery, Kyushu University and Prof. Eiro Tsubura, Dept. of Internal Medicine, Tokushima University). The results were presented in part at the 19th General Meeting of the Japanese Society for Gastroenterological Surgery in February, 1982  相似文献   
73.
Sequence homology was found between the external transcribed spacer and the terminal non-transcribed spacer of Physarum polycephalum rDNA. The homologous sequences were located 2kb upstream from the 19s rRNA gene and 0.3kb downstream from 26S rRNA gene, respectively, and were arranged in a direct repeat manner. Sequence analyses showed that the direct repeats consisted of two parts: one was sequences of about 130bp which showed over 90% sequence homology with each other. The other consisted mainly of many tandem repeats of a 50 to 52bp unit. The direct repeat-rRNA genes-direct repeat unit was found to be flanked by short direct repetitious sequences. Based on these findings, the significance of the direct repeat is discussed in terms of evolution of rDNA.  相似文献   
74.
Succinate dehydrogenase was partially purified from sweet potatoroot tissue by solubilization of the enzyme from the submitochondrialparticles, ammonium sulfate fractionation, and DEAE-cellulosecolumn chromatography. Sweet potato succinate dehydrogenaseexisted in two forms; these were separated by disc polyacrylamidegel electrophoresis or by hydroxyapatite column chromatography.There was a difference in the electric charge of the molecule,but not in the molecular weights of the two forms. No differencewas detected between the two forms of succinate dehydrogenasewith respect to their Km values for succinate, pH-optimums andsubunit compositions. The two subunits that make up the enzymehave molecular weights of about 26,000 and 65,000. 1 This work was supported in part by Grant-in-Aid 411308 forScientific Research from the Ministry of Education, Scienceand Culture of Japan. (Received November 28, 1981; Accepted February 17, 1982)  相似文献   
75.
A new germacranolide isolated from M. sieboldii was shown to be 15-acetoxycostunolide by spectroscopic and chemical methods. 1H NMR spin decoupling and NOE experiments in the presence of a lanthanide shift reagent were used for structure elucidation.  相似文献   
76.
Both nitrogen fixation and acetylene reduction by intact cellsof Anabaena cylindrica were inhibited by oxygen, but nitrogenfixation was invariably less sensitive than acetylene reduction.The C2H2/N2 ratio ranged from 6 to 8 in the absence of oxygen,and it decreased with increase in partial pressure of oxygento 2 at a pO2 of 0.3 atm. (Received June 5, 1979; )  相似文献   
77.
Summary The oncofetal antigen-I (OFA-I) has been defined as an immunogenic antigen that is expressed on human cancer cells and is cross reactive with fetal brain tissue. Quantitative variations in the expression of OFA-I among different cultured melanoma cell lines were determined by absorption techniques based on functionally monospecific anti-OFA-I serum. Allo-antibodies were removed by absorption with lymphoblasts autologous to an OFA-I-positive target cell. Functional monospecificity toward OFA-I was confirmed by complete absorption with a specimen of fetal brain but not by liver from the same fetus.Of 14 melanoma cell lines tested, two did not express OFA-I, whereas 12 expressed the antigen to varying degrees. Five of the cell lines were highly antigenic, and serum absorbed with 5×105 of any of these cell lines could reduce the anti-OFA-I titer (1 : 96) at least four-fold. OFA-I was detected on biopsied melanomas autologous to the antigenic cultured cells. The ability to select highly antigenic cell lines could be useful in further attempts to characterize OFA-I and to monitor tumor immunity in vitro. Antigenic cell lines may improve the response of patients treated in trials of immunotherapy.  相似文献   
78.
A procedure for the simultaneous preparation of S-sulfo-l-cysteine and l-alanine 3-sulfinic acid is described. The method is based on the quantitative reaction between sulfite and S-(2-amino-2-carboxyethylsulfonyl)-l-cysteine. The yield was 95% for S-sulfo-l-cysteine and 91% for l-alanine 3-sulfinic acid. The reaction was also applied to the quantitative determination of sulfite in biological materials. In this procedure, sulfite reacts with S-(2-amino-2-carboxyethylsulfonyl)-l-cysteine. Separation of the reaction product, S-sulfo-l-cysteine, is done by ion-exchange fractionation, and it is determined with acid ninhydrin reagent 2 (M. K. Gaitonde, 1967, Biochem. J.104, 627–663). The recovery was 96.8 ± 0.3%.  相似文献   
79.
Plasma membranes were isolated from lactating bovine mammary gland. Two crude membrane fractions; medium/d 1.033 (light membrane) and 1.033/1.053 interfaces (heavy membrane), were obtained by Ficoll density gradient centrifugation of osmotically washed microsomal fraction. Two crude membranes were further purified separately by sucrose density gradient centrifugation. Both light and heavy membranes banded at a sucrose density of 1.14. The purified membranes appeared as heterogeneous smooth membrane vesicles on electron microscopy. The contaminating suborganelles were not detected. The yield of the purified membranes relative to the homogenate was 1.2%. The degree of purity of the membranes was shown by a great increase in the specific activity of 5′-nucleotidase over the homogenate of 20-fold for light membrane and of 16-fold for heavy membrane. The relative activities of Mg2+-ATPase, (Na+ + K+)-ATPase, γ-glutamyl transpeptidase, phosphodiesterase I, akaline phosphatase and xanthine oxidase were also high (12–18-times) and nearly 20% of these enzymes was recovered. The activity of marker enzyme for mitochondria, endoplasmic reticulum and Golgi apparatus was very low, while that of acid phosphatase for lysosome was relatively high (5-times). DNA and RNA contents were very low. The major polypeptides rich in other suborganelles were not detected profoundly in the membrane fraction and the polypeptide compositions in both light and heavy membranes were similar upon SDS-polyacrylamide gel electrophoresis.  相似文献   
80.
To explore the possibility that cyclic nucleotides control green algal growth and division, Chlamydomonas chemostat cultures were assayed for cyclic nucleotides. Substantial qualities of cAMP were found in cells and in extracellular millieu. Most cGMP molecules were extracellular. Slowing cell growth by slowing chemostat dilution caused reversible changes in cellular morphology and cyclic nucleotide levels. During slowed growth cAMP level increased dramatically; cGMP level decreased. New cells resulting from division were not released from original cell wall.  相似文献   
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