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Summary The presence of human blood-group antigens was analyzed in the rat cochlea during its postnatal development, using anti-A, anti-B and anti-H antibodies. At no stage was reactivity with anti-A antibody observed. With the anti-H antibody, a strong reactivity was observed from 1 to 9 days after birth within hair cells and some other surface epithelial cells of the cochlear duct. After postnatal day 9, only a faint reactivity persisted in a few non-sensory cells. With the anti-B antibody, only hair cells were selectively labeled. At early stages (postnatal day 1 and 3), the reactivity was intense and observed both around the cell surface and within the supranuclear region of cytoplasm. Later on, the reactivity decreased; it was limited at postnatal day 9 to a reactive spot below the cuticular plate. Results are compared with a preliminary finding describing the first appearance of B and H antigens in the organ of Corti at a prenatal stage, and with data concerning other sensory and neural structures. The appearance and progressive disappearance of B and H antigens on sensory and non-sensory cells can be correlated with significant events in the development of the cochlea. The transient expression of B and H antigens in cochlear sensory cells may correspond to developmental changes in their surface glycoconjugates.  相似文献   
2.
The effects of 2,2',5,5'-tetrachlorobiphenyl (TeCB), a PCB congener, and biphenyl on the cytoplasmic membranes of Ralstonia eutropha H850 were investigated by measuring fluorescence polarization using 1,6-diphenyl-1,3,5-hexatriene (DPH) as the probe, and determining the cellular fatty acid compositions. TeCB significantly affected the membrane of R. eutropha H850 cells grown on fructose by decreasing DPH fluorescence polarization. In contrast, the membrane of cells grown on biphenyl showed a considerably less significant effect of TeCB on membrane polarization than in fructose-grown cells. An increase in the ratio of total saturated to unsaturated fatty acids in cells grown on biphenyl suggested less of a fluidizing effect of TeCB on membranes in those cells. When biphenyl-grown cells were transferred back to a fructose medium, they required 25 generations for the membrane polarization and fatty acid compositions of these cells to revert back to those of the initial fructose-grown cells. The re-adaptation to a change in temperature required only five generations to return to normal. These results show that biphenyl affects cells in more ways than simply fluidizing the cytoplasmic membrane.  相似文献   
3.
Based on the genetic model proposing thatH andSe are two structural genes, we predicted that the red cell H-deficient, salivary ABH secretor phenotype should be found on Reunion island, where a large series of H-deficient non-secretor families have been previously described. Two such Reunion individuals are now reported. POU [Ah, Le(a–b+), secretor of A, H, Lea and Leb in saliva] and SOU [Oh, Le(a–b+), secretor of H, Lea and Leb in saliva]. Both are devoid of H -2-fucosyltransferase activity in serum. In addition, the preparation of total non-acid glycosphingolipids from plasma and red cells of POU revealed the type 1ALeb heptaglycosylceramide and small amounts of the monofucosylated type 1 A hexaglycosylceramide. Both glycolipids possess an H structure probably synthesised by the product of theSe gene. No other blood group A glycolipids, with types 2, 3 or 4 chains, normally present in the presence of the product of theH gene, were found on red cells or plasma of POU.TheH,Se andLe genetic control of the expression of ABH and related antigens in different tissue structures of the skin is described in 54 H-normal individuals of known ABO, secretor and Lewis phenotypes; in one red cell H-deficient salivary secretor (SOU); and in one H-deficient non-secretor (FRA). Sweat glands express ABH under the control of theSe gene. Sweat ducts express ABH under the control of bothH andSe genes and Lewis antigens under the control ofLe and bothH andSe genes. Epidermis, vascular endothelium and red cells express ABH under the control of theH gene. The products ofH andSe genes are usually expressed in different cells. However, the results illustrate that in some structures, like the epithelial cells of sweat ducts, both the products ofH andSe genes can contribute to the synthesis of the same Leb structure.  相似文献   
4.
Two variants of recessive, H-deficient nonsecretor individuals (h/h, se/se) were identified on Reunion Island: (1) H-negative individuals corresponding to the classical Bombay phenotypes (OhO, OhA, OhB, OhAB) who lack completely the H antigen on their red cells; all of them were Indian and had strong anti-H antibodies reacting with normal O and Oh red cells from whites; and (2) H-weak individuals (Oh, Ah, Bh, ABh). This phenotype represented the majority (85%) of the H-deficient phenotypes on Reunion Island, and all of them were white. They had only a weak expression of the H antigen and showed small but detectable amounts of ABH antigens on their red cells. Their anti-H antibodies reacted with normal O erythrocytes, but failed to react with Oh red cells, regardless of the ethnic origin of the donor. They were all from the same geographical area on the Island (Cilaos) and showed homogeneous titers of anti-H antibodies in sera. We propose to call this particular variant of weak H phenotype, belonging to the so-called para-Bombay series, Reunion.  相似文献   
5.
A radioimmunoassay specific for the H type 1 antigenic determinant demonstrated that the H type 1 antigen is under the strict control of the Se gene in both serum and saliva. Similar amounts of H type 1 antigenic determinants were found in saliva from Se/-, le/le donors and in saliva from Se/-, Le/- donors. However, sera from Se/-, le/le donors were about 100 times more efficient in inhibiting the H type 1 assay than were sera from Se/-, Le/- donors. A radioimmunoassay, based on the binding of Ulex europaeus with the H type 2 antigenic determinant, showed that all the H type 2 antigen in saliva is under the control of the Se gene, while only one-third of the H type 2 antigen present in serum is under the control of this gene. The remaining two-thirds of H type 2 antigen in sera is independent of the ABH secretor status of the donor. The amount of H type 2 antigen in both serum and saliva is independent of the Le gene. These results are compatible with the existence of two alpha (1 leads to 2) fucosyl-transferases but suggest that the enzyme of epithelial origin, coded by the Se gene, should be able to transform both type 1 and type 2 natural substrates, while the enzyme of mesodermic origin, coded by the H gene, would work preferentially on the natural type 2 substrates.  相似文献   
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