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511.
J. Lindgren T. Wahlström B. Bång M. Hurme O. Mäkelä 《Histochemistry and cell biology》1982,74(2):223-227
Summary Mouse monoclonal antibodies to carcinoembryogenic antigen (CEA) obtained by the somatic cell hybridization technique of Köhler and Milstein were used in a modified enzyme bridge immunoperoxidase staining method. Both high and low affinity antibodies were tested and their staining properties compared with those of a commercial polyvalent rabbit antiserum. The staining pattern of neoplastic epithelial cells in all seven antibodies in samples of primary adenocarcinoma of the colon was similar, indicating that no gross differences were found in the exposure of the different antigenic determinants of CEA in formalin fixed tissue. The background staining of the monoclonal antibodies was negligible. It is concluded that monoclonal antibodies are superior to conventional antisera in immunoperoxidase staining of CEA. 相似文献
512.
Amylolytic lactic acid bacteria in fish silage 总被引:2,自引:1,他引:1
An ∝aL-amylase activity has been observed in lactic acid bacteria occurring initially in fermented fish silage. The organisms belong to the genus Leuconostoc . The main fraction of the amylolytic enzyme produced by one of the isolated bacteria is cell-bound and is released into the medium at a late stage of growth. Treating cells with ultrasound or Triton X-100 increases enzyme activity in the culture filtrate. The pH range for enzyme activity is 5.0–7.0, with an optimum at pH 6.0. The enzyme is extremely labile at pH 8.0 and is inactivated at temperatures above 50°C at pH 5.8. Two enzyme fractions were found by isoelectric focusing, the main one at pH 5.00 and another at pH 4.5. Chromatography on DEAE cellulose gave two active peaks. 相似文献
513.
Franca Dagna Bricarelli M. Fraccaro J. Lindsten U. Müller P. Baggio Laura Doria Lamba Carbone A. Hjerpe F. Lindgren Antonia Mayerová H. Ringertz E. M. Ritzén D. C. Rovetta C. Sicchero U. Wolf 《Human genetics》1981,57(1):15-22
Summary Three families with infants affected with campomelic dysplasia, a genetically determined mesenchymal disease frequently associated with sex reversal were studied. Two XY famales with ovarian gonadal differentiation and typical clinical features of campomelic dysplasia could be tested for H-Y antigen and were found to be H-Y negative. 相似文献
514.
Particle-size distribution of very low density plasma lipoproteins during fat absorption in man 总被引:2,自引:0,他引:2
The size distributions of electrophoretically isolated subfractions of the very low density human plasma lipoproteins have been determined using electron microscopy. The primary and secondary particles observed in plasma of normal subjects after fat ingestion appear to have similar size distributions. Particles produced by corn oil feeding can be fixed by the osmium tetroxide reaction while those produced by butter fat feeding could not be fixed or made visible by this technique. Good agreement between particle size as measured by electron microscopy and particle size as predicted by ultra-centrifugal analysis was obtained. 相似文献
515.
Transformations of chloroguaiacols, chloroveratroles, and chlorocatechols by stable consortia of anaerobic bacteria. 总被引:8,自引:7,他引:1 下载免费PDF全文
Metabolically stable consortia of anaerobic bacteria obtained by enrichment of sediment samples with 3,4,5-trimethoxybenzoate (TMBA), 3,4,5-trihydroxybenzoate (gallate [GA]), or 5-chlorovanillin (CV) were used to study the anaerobic transformation of a series of chloroveratroles, chloroguaiacols, and chlorocatechols used as cosubstrates. Experiments were carried out with growing cultures, and the following pathways were demonstrated for metabolism of the growth substrates: (i) TMBA produced GA, which was further degraded without the formation of aromatic intermediates; (ii) GA formed pyrogallol, which was stable to further transformation; and (iii) CV was degraded by a series of steps involving de-O-methylation, oxidation of the aldehyde group, and decarboxylation to 3-chlorocatechol before ring cleavage. Mono-de-O-methylation of the cosubstrates occurred rapidly in the order 4,5,6-trichloroguaiacol greater than 3,4,5-trichloroguaiacol approximately 3,4,5-trichloroveratrole approximately tetrachloroveratrole greater than tetrachloroguaiacol and was concomitant with degradation of the growth substrates. For the polymethoxy compounds--chloroveratroles, 1,2,3-trichloro-4,5,6-trimethoxybenzene, and 4,5,6-trichlorosyringol--de-O-methylation took place sequentially. The resulting chlorocatechols were stable to further transformation until the cultures had exhausted the growth substrates; selective dechlorination then occurred with the formation of 3,5-dichlorocatechol from 3,4,5-trichlorocatechol and of 3,4,6-trichlorocatechol from tetrachlorocatechol. 2,4,5-, 2,4,6-, and 3,4,5-trichoroanisole and 2,3,4,5-tetrachloroanisole were de-O-methylated, but the resulting chlorophenols were resistant to dechlorination. These results extend those of a previous study with spiked sediment samples and their endogenous microflora and illustrate some of the transformations of chloroguaiacols and chlorocatechols which may be expected to occur in anaerobic sediments. 相似文献
516.
517.
W L Neuman M M Le Beau R A Farber V Lindgren C A Westbrook 《Cytogenetics and cell genetics》1992,61(2):103-106
As a means of characterizing the distal long arm of chromosome 5, in particular, the region spanning 5q23-->q31, we analyzed somatic cell hybrids prepared from cells with overlapping chromosomal rearrangements. In one hybrid, the derivative chromosome 5 from a patient with acute myeloid leukemia (AML) de novo, whose bone marrow cells had a balanced translocation, t(5;7)(q31;q22), involving chromosome band 5q31, was isolated in a somatic cell hybrid (B294). In addition, we prepared somatic cell hybrids from a lymphoblastoid cell line (CC) derived from a patient who has a constitutional interstitial deletion of chromosome 5 spanning 5q23.1-->q31.1. By a combination of Southern hybridization analysis and fluorescent in situ hybridization, we constructed a map dividing 5q23-->q31 into four regions. We can assign genes to these regions and relate them to anonymous RFLP markers that have been genetically mapped. 相似文献
518.
Recent chromosome walking experiments have identified a candidate gene (ZFY) for the testis-determining factor on the human Y chromosome (Page et al., 1987). We report here the regional assignments of the ZFY gene and related sequences in the human and the mouse. By in situ hybridization, we assigned ZFX and ZFY to human chromosome bands Xp21 and Yp11.3, respectively. Although the mouse harbors two Zfy genes, only one site at band A1 of its Y chromosome was significantly labeled. The mouse Zfx gene and the Zfa gene on chromosome 10 were assigned to bands XD and 10B5, respectively. These assignments of the ZFX gene in human and mouse add another marker to the conserved syntenic group for evaluating the evolutionary relationship of the human and mouse X chromosomes. 相似文献