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991.
992.
We have identified the major antigens or IgE binding components from wheat flour. Thirty-five sera from patients with baker's asthma were used to analyze the reaction with wheat salt-soluble proteins. We found a 15 kDa SDS-PAGE band which reacted with all sera tested. Purified members of the alpha-amylase inhibitor family, which are the main components of the 15 kDa band, were recognized by specific IgE when tested with a pool of reactive sera. Immunodetection after two-dimensional electrophoretic fractionation of crude inhibitor preparations from wheat endosperms also detected several inhibitor subunits as major low-molecular-weight allergens.  相似文献   
993.
The present work was undertaken to evaluate the distribution of the Na-ATPase activity in the different components of the rat kidney cortex. Suspensions of glomeruli, proximal and distal tubules were prepared following a collagenase digestion of outermost kidney cortex slices and a separation on a Percoll gradient. It was found that the Na-ATPase activity is higher in the fraction enriched in proximal tubules. The fraction enriched in glomeruli and in distal tubules show also a Na-ATPase activity, but it is lower.  相似文献   
994.
In ten infants divided into two groups (up to one month of age and at 2–7 months of age) the dynamics and formation of different antibody isotypes produced locally in the intenstine and in serum after orally administered inactivated enteropathogenicE. coli strains O111 and O55 was followed during 30 d after the first and booster dose by using an indirect immunofluorescence method. Infants up to one month of age produced antibodies of IgM isotype in stool together with the IgA isotype after the first and booster dose of the vaccine against both antigens. Serum IgG antibody increased after 2 d following the first and second dose of antigens and remained higher during 5 d. The infants aged 2–7 months expressed predominantly the IgA isotype response in stool after the first and booster dose of antigens. The serum immunoglobulin levels did not change after oral antigen administration.  相似文献   
995.
We examined the effects of 5 soluble derivatives of yeast glucan on the formation of exogenous (CFU-S) and endogenous (E-CFU) colony-forming units in the spleens of sublethally irradiated (60Co, 6.5–7.0 Gy) mice of two inbred strains. For the estimation of CFU-S, glucans were administered intravenously either to donors or recipients of spleen cells 24 h prior to irradiation or removal of the spleen. The number of CFU-S was increased when both the donors and recipients were treated with glucan; the highest increase was obtained with glucans S, P and K. All glucan preparations increased significantly also the number of E-CFU even when administered 90 min after irradiation. There exist differences in the response to the stimulatory effect of glucans among individual mouse strains. Thus, for example, the stimulatory effect of glucan KM on the E-CFU number was significantly more pronounced in strain A/Ph than in strain C57B1/6.  相似文献   
996.
The inhibitory capacity of strain S-48 ofEnterococcus faecalis ssp.liquefaciens was studied. The strain produces a broad-spectrum peptide antibiotic (AS-48) that has been characterized elsewhere. The isolation of mutants from S-48 after mutagenic treatment revealed another inhibitory substance which remained masked in the wild strain. The protein nature and restricted spectrum of this substance points to its being a bacteriocin (Bc-48).  相似文献   
997.
998.
Lake Gallocanta has undergone drastic changes during the last thirteen years. Water level changed from a high level (Zmax = 2 m) to total dryness in 1985. From 1986 to 1988 slow refilling occurred. The water volume fluctuations have been studied in relation to climatic variations recorded for that period. Variations in the major dissolved ions were related to water volume fluctuations from data at two different stages, one corresponding to the drying phase and another to the refilling phase. Mineralogical composition of the salts precipitated at different stages was examined by X-ray diffraction. Interstitial water and mineralogical composition of recent sediments were also studied along a transect through the lake.The water column decrease from 1977 to 1985 is related to decreasing annual rainfall (500-250 mm respectively). The refilling in 1986–1988 is due to high annual rainfall (537 mm). In addition to these fluctuations, seasonal changes of the water level between 20 and 50 cm occurred every year.Gallocanta is a Na-Mg-Cl-(SO4) type lake. During the drying period a typical salt enrichment occurs with linear relationships between TDS, Cl, Na and K. Alkalinity is linearly correlated with Ca at relatively low salinities. As salinity increases a linear relationship between Ca and SO4 is observed. Minerals formed from the brine are halite, bischofite, epsomite, hexahydrite, mirabilite, gypsum, aragonite, calcite and dolomite. The molar ratio Mg/Ca of the interstitial water changes from 1.5 along the shorelines, where calcite and aragonite precipitate, to 40 in the center of the lake. Sediment cores from the central part of the lake show aragonite in the top layers, magnesian calcite and low proportions of quartz and illite, while at 20 cm depth a high proportion of gypsum is present. In contrast, cores from the shore of the lake are mainly composed of low magnesium calcite in the top layers and low magnesium calcite together high magnesium calcite and dolomite between 30 and 70 cm depth. Gypsum deposits only occur in significant proportions at 80–100 cm depth.The refilling process showed relationships between volume and salt concentration following the Langbein model. The salt mass in solution decreased about 50% from the drying to the refilling phase. However, Mg content decreased about 70 % for the same period, suggesting a contribution of this element to the dolomite formation.  相似文献   
999.
1. 31P NMR was used to characterize phosphate pools in perchloric acid extracts of muscles with various composition of muscle fibre types. 2. The white m. pectoralis major (MPM) of chickens 15 min post mortem is characterized by 1.6-times higher relative content of phosphocreatine (PCr) in comparison with mixed leg muscle (LM) of this species. The glycerophosphorylcholine (GPC) does not occur in MPM at NMR detectable level in contrast to the leg muscles. Relative amounts of other phosphates are similar in both muscles. 3. The intermediate MPM of pigeons as well as mixed LM of this species contain 15 min post mortem a very small amount of PCr and ATP but a large amount of inorganic phosphate. Relative content of GPC is higher in leg muscles than in intermediate MPM. 4. Muscles with higher occurrence of white fibres contain relatively more PCr than muscles with lower occurrence of white fibres. 5. The occurrence of GPC seems to be connected with metabolism of red muscle fibres.  相似文献   
1000.
We have identified the gene for the yeast nucleolar protein p38 and deduced the primary structure of p38 from its sequence. We propose the name NOP1 (nucleolar protein 1) for this gene. NOP1 encodes a 327 amino acid protein of 34,470 daltons and is flanked by potential promoter and polyadenylation sequences. Blot analyses indicate that the mRNA transcribed from NOP1 is approximately 1.3 kilobases in size and that there is one NOP1 gene per haploid genome. The amino-terminal sequence of p38 is homologous with the 31 known amino-terminal residues of the autoimmune antigen fibrillarin, confirming the previously observed similarity between p38 and this mammalian nucleolar protein. Consistent with this, p38 cross-reacts with serum from a patient with the autoimmune disease scleroderma. A putative nuclear localization signal can be identified in p38. Interestingly, a repetitive amino acid sequence motif begins near the amino terminus of p38. This motif is approximately 80 residues long, is rich in glycine and arginine, and shows striking sequence homology to mammalian nucleolins and certain nucleic acid binding proteins.  相似文献   
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