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61.
Isolation of a suppressor mutant in Bacillus subtilis.   总被引:25,自引:16,他引:9  
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62.
Peripheral mononuclear cells (PBL) from tuberculin reaction (TR)-negative tuberculous pleurisy patients proliferated poorly with PPD, while the cells of pleural effusion from these patients showed a proliferative response to PPD as well as did the healthy control PBL. Surface antigens of peripheral blood and pleural effusion were examined by using monoclonal antibodies. The Leu 1-positive cell population can be divided into four groups, namely (1) Leu 1+, Leu2a+, Leu 3a+, (2) Leu 1+, Leu 2a+, Leu 3a-, (3) Leu 1+, Leu 2a-, Leu3a+, and (4) Leu 1+, Leu 2a-, Leu 3a- cell populations. Results of analysis of surface antigens of PPD-specific proliferative cells in peripheral blood and pleural effusion from tuberculous pleurisy patients as well as healthy controls indicate that the PPD-specific proliferative response is mediated by Leu 1+, Leu 2a-, Leu 3a+ cells and Leu 1+, Leu 2a-, Leu3a- cells.  相似文献   
63.
Two isozymes of porcine aromatase, the placental and the blastocyst forms, were expressed in CHO cells using the mammalian cell transfection method. Using an 'in-cell' assay (a 3H-water release method), catalytic parameters of the porcine placental aromatase were found to be very similar to those of the human enzyme; however, the activity of the blastocyst isozyme was found to be one-thirtieth that of the placental isozyme. Product isolation assay (using testosterone as the substrate) revealed that the major steroid products were 17beta-estradiol and 19-nortestosterone. The product ratio of estradiol/19-nortestosterone was found to be 94 : 6 for the porcine placental form, 6 : 94 for the porcine blastocyst form, and 92 : 8 for the human wild-type aromatase. Therefore, the porcine blastocyst aromatase isozyme catalyzes mainly androgen 19-desmethylation rather than aromatization. In addition, inhibition profile analyses on the placental and blastocyst isozymes were performed using three steroidal inhibitors [4-hydroxyandro-stenedione (4-OHA), 7alpha-(4'-amino)phenylthio-1, 4-androstandiene-3,17-dione (7alpha-APTADD), and bridge (2, 19-methyleneoxy) androstene-3,17-dione (MDL 101,003)], and four nonsteroidal inhibitors [aminoglutethimide (AG), CGS 20267, ICI D1033, and vorozole (R83842)]. While the two isozymes of porcine aromatase share 93% amino-acid sequence identity, our results indicate that the two porcine aromatase isozymes have distinct responses to various aromatase inhibitors.  相似文献   
64.
The genetics of bacteriophage SPO1   总被引:24,自引:0,他引:24  
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In 2017, novel human metapneumovirus (HMPV) A2b subgroup strains with a 111‐nucleotide duplication in the G gene was detected by the present team. These strains were related to previously identified HMPV A2b strains with a 180‐nucleotide duplication; however, they appeared to be different strains, produced by an independent duplication event. The recent evolution of HMPV suggests that careful monitoring of this virus is required.
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In order to establish a successful method for the transplantation of branching and tabular coral fragments, we tested the effects of orientations of attachment, seasons of transplantation, and size of fragments on survival, growth, and spawning using Acropora formosa and A. hyacinthus. Vertically attached, large-sized fragments of A. formosa showed 98–100% survival rate after 18 months. The fragments transplanted in August exhibited better survival than those transplanted in November. The larger fragments had the higher percentage of spawning. The fragments that spawned had lower growth rate, while those resorbed the oocytes carried at the time of transplantation showed higher growth rate, suggesting the trade-off between growth and reproduction. Half of the fragments spawned 1 month earlier than the donor colonies. Only the vertically attached fragments of A. hyacinthus fused to the substratum, and those transplanted in February showed 100% survival rate after 14 months, indicating that this species is well suited for transplantation.  相似文献   
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