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11.
The cure of osteopetrosis by allogenic bone marrow injection has been obtained in "op" mutant rat kept under cyclosporin A treatment. This immunosuppressive agent able to prevent the rejection of transplanted cells does not impair the propriety of these cells to restore the bone resorption process in this severe osteopetrotic form.  相似文献   
12.
Reports on how changes in microtubule (MT) distribution or polymerization affect the distribution of intermediate filaments (IFs) differ. Therefore, we have used cytoimmunofluorescence techniques and electron microscopy to systematically examine and compare the arrangements of MTs and IFs in cultures of chick embryo fibroblasts under the following conditions: at different times during the cell cycle, in the presence of Colcemid or of taxol, in the presence of both drugs in succession or simultaneously in varying ratios, and during recovery from treatment with Colcemid or taxol. We have found that depolymerization of MTs by 1 microM Colcemid resulted in the rapid formation of massive IF-cables, structures distinct from "collapsed IFs" or "juxtanuclear coils." Neither the rapid formation of IF-cables nor their dispersion during recovery required protein synthesis. Cells treated with 10 microM taxol rapidly formed MT-bundles, as well as aggregates of intertwining IFs, termed "IF-skeins." MT-bundles and IF-skeins displayed strikingly complementary distributions. This reciprocal distribution of packed MTs and IFs was also obvious in untreated anaphase and telophase cells. When 10 microM taxol and 1 microM Colcemid were applied simultaneously, the complementary distributions of MT-bundles and IF-skeins mimicked those in taxol alone. This ability of taxol to block Colcemid's effects was concentration dependent. Decreasing the taxol: Colcemid ratio allowed the depolymerization of MTs, which correlated with the formation of IF-cables.  相似文献   
13.
An exogenous ternary complex composed of Tween 80, ergosterol, and albumin increased the final ethanol concentration of fermentation by sake yeasts from 17.2 to 19.0% (vol/vol) and reduced the fermentation time from 30 to 25 days. Likewise, a complex of monoolein, albumin, and either ergosterol or ergosteryl oleate increased the final ethanol concentration of fermentation to 19.7 or 19.8% (vol/vol), respectively, and reduced the fermentation time to 25 days. Both Tween 80 and monoolein promoted the fermentative activity (QCO2) of cells, and the effect was enhanced by the presence of ergosterol.  相似文献   
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Close linkage of MEN2A with RBP3 locus in Japanese kindreds   总被引:7,自引:0,他引:7  
Summary The gene responsible for multiple endocrine neoplasia type 2A (MEN2A) has recently been assigned to the pericentromeric region of chromsome 10 in European Caucasian kindreds by linkage analysis using a DNA marker, interstitial retinol-binding protein 3 (RBP3). We have found tight linkage between the MEN2A and RBP3 loci in Japanese MEN2A kindreds. The maximum lod score is 5.19 at a recombination fraction of 0.00. This result suggests that mutation of a certain gene close to RBP3 is responsible for MEN2A irrespective of ethnic backgrounds.  相似文献   
16.
Abstract Polymerase chain reaction was carried out to amplify the conserved region (789 bp in the case of Mycoplasma capricolum ) of the dnaA gene (1350 bp in the case of M. capricolum ) of 15 representatives of the class Mollicutes using degenerate oligonucleotide primers. The dnaA gene fragments were amplified from M. mycoides subsp. capri, Spiroplasma apis and S. citri . The amino acid sequences deduced from the nucleotide sequences of the amplified fragments showed very low similarities to those of the corresponding regions of four walled bacteria. The values of similarity between any two of the three mollicute species were lower than those between any two of the four walled bacteria.  相似文献   
17.
This paper describes an attempt to effectively induce antibody-dependent cell-mediated cytotoxicity (ADCC) in nude mice. A monoclonal antibody against α-fetoprotein, 80G, coadministered with spleen cells from other nude mice bearing HuH-7N (xenograft of human hepatoma cell line, HuH-7) significantly suppressed the growth of HuH-7N as compared to treatment with 80G alone. 80G with spleen cells from normal nude mice also had some suppressive effect. In contrast, no effect was observed with each spleen cells alone as well as 80G alone. These results suggest that further supply of effector cells could enhance ADCC activity in nude mice.  相似文献   
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This study was carried out to clarify the reason for elevation of serum α-fetoprotein (AFP) level of nude mice bearing hepatoma cells after treatment with monoclonal antibodies (MoAbs) to AFP. MoAbs to AFP showed no effect on the cumulative amounts of AFP secreted from human hepatoma cell line, HuH-7, in vitro. However, the treatment of nude mice bearing HuH-7N cells (HuH-7 xenograft) with MoAbs to AFP led to elevation of the serum AFP level in spite of the fact that the growth curve of HuH-7N cells was similar to that for PBS treatment. This apparent elevation of the serum AFP level is thought to be due to the slow elimination of AFP-MoAb immune complexes with little lattice structure from circulation, but not the enhancement of AFP secretion of HuH-7N cells. Thus, when using a MoAb alone or MoAb-drug conjugate, the serum AFP level should only be cautiously used as a tumor marker for evaluating the targeting immunotherapy.  相似文献   
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