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61.
We defined the chemical structure and the genetic control of the various A or B determinants expressed by pyloric and duodenal epithelial cells by indirect immunofluorescent staining using monoclonal anti-A or anti-B reagents that recognize only certain variants of A or B antigenic determinants.Some mucous cells in pyloric and Brünner's glands express AY or BY antigens whereas other mucous cells in the same glands express only the Y antigen. Absorptive and goblet cells of the duodenal villi and Lieberkühn glands express mono- and difucosylated A or B structures, mainly of type 1. The pyloric surface epithelium expresses mono- and difucosylated, type 1 and type 2, A or B structures. In addition, A or B antigens, with a so far undefined structure are found in the pyloric surface mucosae of non-secretor individuals.  相似文献   
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A new anti-blood group H lectin was isolated from the seeds ofGalactia tenuiflora. This lectin is mostly specific for the H type 2 trisaccharide but it shows some cross-reactivity with the H type 4 and H type 3 trisaccharides. Differences between this lectin and lectin 1 fromUlex europaeus are described. These differences concern the respective abilities of the lectins to recognize erythrocytes from some H deficient phenotypes, the inhibitions by salivas and the tissue distribution of the antigens recognized by the two lectins. The most important differences were noted in the surface epithelium of the stomach. This area is known to express ABH antigens under the control of theSe gene as defined by theUlex europaeus lectin 1, yet it is always strongly labelled by theGalactia tenuiflora lectin irrespective of the secretor status of the tissue donor.  相似文献   
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The three-dimensional structures of fourteen histo-blood groups carbohydrate antigens have been established through a combination of molecular mechanics and conformational searching methods. The conformational space available for each disaccharide, constituents of these determinants, has been throroughly characterized. The results have been organized in a data bank fashion. Larger relatives, i.e. 14 tri- and tetrasaccharides of histo-blood group antigens, have been modelled using a different method for exploring the complex potential energy surface. This approach is aimed at establishing all the possible families of conformations, along with the conformational pathways. Different conformational behaviours are exhibited by these oligosaccharides. Some of them, i.e. LeX and LeY tri and tetrasaccharides, are very rigid; 99% of their populations belong to the same conformational family. Others, like H type 1, H type 2 or H type 6 oligosaccharides, are essentially rigid, but a secondary conformational family, corresponding to 3–4% of the total population, can arise. Finally, the H types 3 and 4 trisaccharides, and the A type 1 and A type 2 tetrasaccharides are predicted to behave rather flexibly. The information gathered in the present investigation has been used to analyse the body of experimental evidence, either physical or biological, available for this series of carbohydrate antigens. Of special interest are the several different alignments that can be proposed for these molecules. They yield a realistic definition of the three-dimensional features of the epitopes thereby providing essential information about how carbohydrate antigens are recognized by proteins.  相似文献   
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The cyclin-dependent kinase (CDK) inhibitor p21(Cip1) has a dual role in the regulation of the cell cycle; it is an activator of cyclin D1-CDK4 complexes and an inhibitor of cyclins E/A-CDK2 activity. By affinity chromatography with p21(Cip1)-Sepharose 4B columns, we purified a 39-kDa protein, which was identified by microsequence analysis as the oncoprotein SET. Complexes containing SET and p21(Cip1) were detected in vivo by immunoprecipitation of Namalwa cell extracts using specific anti-p21(Cip1) antibodies. We found that SET bound directly to p21(Cip1) in vitro by the carboxyl-terminal region of p21(Cip1). SET had no direct effect on cyclin E/A-CDK2 activity, although it reversed the inhibition of cyclin E-CDK2, but not of cyclin A-CDK2, induced by p21(Cip1). This result is specific for p21(Cip1), since SET neither bound to p27(Kip1) nor reversed its inhibitory effect on cyclin E-CDK2 or cyclin A-CDK2. Thus, SET appears to be a modulator of p21(Cip1) inhibitory function. These results suggest that SET can regulate G(1)/S transition by modulating the activity of cyclin E-CDK2.  相似文献   
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Summary This study reports a case of a male patient, the first in Spain, afflicted with tuberous and vegetating lesion of the skin: actinomycosis vegetans. The culture for the causative organism remained negative. The histologic sections, however, showed typical, polynuclear-lymphocytic, dermal infiltration with micro-abscesses with the typical actinomycotic granules. Also the first case of Blastomycosis of the skin is presented. There were many round, double contoured bodies in the center of the abscesses. The culture was positive for micrococcus or torula.

Trabajo presentado al ler Congreso de la Sociedad Internacional de Dermatología Tropical. Napoles. Junio 8–13, 1964.  相似文献   
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A double antibody radioimmunoassay in estudied for the determination of PGF2alpha. Its sensitivity allows to detect 0.4 ng. The reproductibility in this assays is of 7.8 % while between assays is of 10.7 %. No detectable levels (less than 0.8 ng/ml) could be found on blood obtained from the right heart chambers during the menstrual cycle, but they were measured in peripheral blood during normal deliveries. Changes on PGF2alpha concentrations occur in the endometrium along the menstrual cycle. Tis is a relatively simple method useful either for farmocodinamical studies when administering PGF2alpha or for physiological work with tissure showing relatively high concentrations of this compound.  相似文献   
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