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81.
A seroepidemiological survey was performed on antibody against parapoxvirus among cattle in Japan using the agar gel immunodiffusion test and enzyme-linked immunosorbent assay. A total 1,819 sera were collected from cattle in various parts of Japan for the survey. The positive rates were in the range of 40 to 98%, and the reactors increased gradually in number with advancing age. These results indicate that parapoxvirus infection is already prevalent among cattle in Japan. It remains to be elucidated, however, whether the antibodies detected have been produced by infection of the same virus or other viruses that belong to the genus parapoxvirus.  相似文献   
82.
Simultaneous correction of the alignment and the shortening of the deformed little finger in congenital synostosis of the fourth and fifth metacarpals was accomplished by insertion of a wedge-shaped bone block harvested from the fusion site following transverse osteotomy of the fifth metacarpal. Correction can be performed simply and successfully without morbidity of the donor site when this technique is applied to suitable patients.  相似文献   
83.
Cyclin E as a coactivator of the androgen receptor   总被引:7,自引:0,他引:7  
Androgens play an important role in the growth of prostate cancer, but the molecular mechanism that underlies development of resistance to antiandrogen therapy remains unknown. Cyclin E has now been shown to increase the transactivation activity of the human androgen receptor (AR) in the presence of its ligand dihydrotestosterone. The enhancement of AR activity by cyclin E was resistant to inhibition by the antiandrogen 5-hydroxyflutamide. Cyclin E was shown to bind directly to the COOH terminus portion of the AB domain of the AR, and to enhance its AF-1 transactivation function. These results suggest that cyclin E functions as a coactivator of the AR, and that aberrant expression of cyclin E in tumors may contribute to persistent activation of AR function, even during androgen ablation therapy.  相似文献   
84.
Alpha-N-acetylgalactosaminidase (alpha-GalNAc-ase; EC 3.2.1.49) is an exoglycosidase specific for the hydrolysis of terminal alpha-linked N-acetylgalactosamine in various sugar chains. The cDNA, nagA, encoding alpha-GalNAc-ase from Acremonium sp. was cloned, sequenced, and expressed in yeast Saccharomyces cerevisiae. The nagA contains an open reading frame which encodes for 547 amino acid residues including 21 residues of a signal peptide in its N-terminal. The calculated molecular mass of mature protein from the deduced amino acid sequence of nagA is 57260 Da, which corresponds to the value obtained from SDS-PAGE of native and recombinant enzymes treated with endo-beta-N-acetylglucosaminidase H. The amino acid sequence of NagA showed significant similarity to those of eukaryotic alpha-GalNAc-ases and alpha-galactosidases (alpha-Gal-ases), particularly alpha-Gal-ase A (AglA) from Aspergillus niger. Phylogenetic analysis revealed that NagA does not belong to the cluster of vertebrate alpha-GalNAc-ase and alpha-Gal-ase but forms another cluster with AglA and yeast alpha-Gal-ases. Thus, the evolutionary origin of the fungal alpha-GalNAc-ase is suggested to be different from that of vertebrate alpha-GalNAc-ase. This is the first report of a microbial alpha-GalNAc-ase gene.  相似文献   
85.
After WWII, ultra-nationalism, which was the leading ideology of wartime Japan, seemed to have lost its power to inspire the Japanese. In the 1960s, when the Japanese began to enjoy economic prosperity, Yukio Mishima, deploring that the Japanese were losing the traditional spirit and morality of the nation, was one of those citizens who felt a strong nostalgia for wartime Japan. In an attempt to revive the spiritual exaltation of wartime Japan, Mishima took radical action as an ultra-nationalist, and killed himself by Hara-kiri. Mishima's ethical concepts, which center on the ethos of warriors who dedicate themselves to the defense of their commune, have structural similarities to the ethical structure of the Kanun, which may be called the ethics of "blood". Mishima's theory of ultra-nationalism has a paradoxical logic, which seems to be related to the ethical concepts of a society without state power.  相似文献   
86.
Arachidonate 12-lipoxygenase of porcine leukocytes, which was purified to homogeneity by immunoaffinity chromatography, was analyzed for iron content by atomic absorption spectrophotometry. The enzyme contained 0.70 +/- 0.09 g atom of iron per mol of enzyme (mean +/- S.D., n = 4). Inorganic iron, which was added to the enzyme solution as an internal standard, was recovered in almost 100% yield. Among various iron chelators tested, only 2,2'-dipyridyl at 1 mM inactivated the enzyme by 87%, but the enzyme was not reactivated by the addition of excess ferrous or ferric iron.  相似文献   
87.
The mechanism of DNA damage by hydrazine in the presence of metal ions was investigated by DNA sequencing technique and ESR-spin trapping method. Hydrazine caused DNA damage in the presence of Mn(III), Mn(II), Cu(II), Co(II), and Fe(III). The order of inducing effect on hydrazine-dependent DNA damage (Mn(III) greater than Mn(II) approximately Cu(II) much greater than Co(II) approximately Fe(III)) was related to that of the accelerating effect on the O2 consumption rate of hydrazine autoxidation. DNA damage by hydrazine plus Mn(II) or Mn(III) was inhibited by hydroxyl radical scavengers and superoxide dismutase, but not by catalase. On the other hand, bathocuproine and catalase completely inhibited DNA damage by hydrazine plus Cu(II), whereas hydroxyl radical scavengers and superoxide dismutase did not. Hydrazine plus Mn(II) or Mn(III) caused cleavage at every nucleotide with a little weaker cleavage at adenine residues, whereas hydrazine plus Cu(II) induced piperidine-labile sites frequently at thymine residues, especially of the GTC sequence. ESR-spin trapping experiments showed that hydroxyl radical is generated during the Mn(III)-catalyzed autoxidation of hydrazine, whereas hydrogen atom adducts of spin trapping reagents are generated during Cu(II)-catalyzed autoxidation. The results suggest that hydrazine plus Mn(II) or Mn(III) generate hydroxyl free radical not via H2O2 and that this hydroxyl free radical causes DNA damage. A possibility that the hydrogen atom releasing compound participates in hydrazine plus Cu(II)-induced DNA damage is discussed.  相似文献   
88.
CD8+ CTL inhibit the replication of HIV and simian immunodeficiency virus of macaques (SIVmac) in PBL and, therefore, are likely to play an important role in containing the spread of the AIDS virus in infected individuals. We have generated a series of gag-specific lytic T lymphocyte clones from PBL: of an SIVmac-infected rhesus monkey. These T cell clones are CD3+CD8+ and are MHC class I-restricted in their target specificity. They are, therefore, CTL. Interestingly, all gag-specific CTL clones, as well as the gag-specific lytic activity of PBL of this monkey, demonstrated specificity for a single 25 amino acid fragment of the SIVmac gag protein. Moreover, they were restricted in their lytic function by a single MHC class I allele. These findings illustrate a powerful method for cloning AIDS virus-specific T lymphocytes and demonstrate a remarkably restricted epitope specificity of this AIDS virus-specific CTL response.  相似文献   
89.
Summary We report that plasmid R46 provides a function which promotes recA-independent deletion, replicon fusion, and resolution of the fusion. R46 belongs to the incompatibility group N and specifies resistance to ampicillin, tetracycline, streptomycin and sulfonamide. Four kinds of deletion derivatives were observed by selection for susceptability to tetracycline from ampicillin-resistant clones. A common region, will be called region thereafter, was postulated to be involved in these deletions. The replicon fusion occurred by a conjugative mobilization of each derivative with plasmid R388. The fusion was suggested to contain both replicons linked at each junction by the sequence in the region in direct orientation. The resolution of the replicon fusion was found between two regions and a consequently generated, parental deletion derivative and an R388 derivative which gained one region. It is possible that the region contains one potential Insertion Sequence (IS) element. These events were also speculated to occur as a consequence of insertion of the potential IS onto the intramolecular or intermolecular target sequence, or reciprocal recombination between two potential IS elements.  相似文献   
90.
The time of onset of the constrictive effect of indomethacin on the ductus arteriosus (DA) in fetal rats was assessed by measurement of the caliber of the DA after maternal treatment with indomethacin on days 19-21 of gestation. The day following overnight mating was regarded as day 0 of gestation. Observation was performed by direct exposure of the DA by hand shaving of intact frozen fetuses. On days 20 and 21, the DA was significantly constricted 3 h after maternal treatment with 1 mg/kg of indomethacin. When the DA was examined at 19 1/2 and 19 2/3 days of gestation (3 h after indomethacin exposure), it was significantly constricted at 19 2/3 days but not at 19 1/2 days. Higher doses of indomethacin (10 and 100 mg/kg) induced a significant constriction of the DA at day 19 1/2, but not at the beginning of the same day (1.00 a.m.). These results suggest that the onset of the susceptibility of the DA to the constrictive effect of indomethacin occurs in the first half of day 19 of gestation.  相似文献   
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