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1.
Two compounds with highly potent juvenile hormone activity were isolated and identified from the oil of sweet basil, Ocimum basilicum L., Labiatae.  相似文献   
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The Ppd-A1 genotype of 240 Japanese wheat cultivars and 40 foreign cultivars was determined using a PCR-based method. Among Japanese cultivars, only 12 cultivars, all of which were Hokkaido winter wheat, carried the Ppd-A1a allele, while this allele was not found in Hokkaido spring wheat cultivars or Tohoku-Kyushu cultivars. Cultivars with a photoperiod-insensitive allele headed 6.9–9.8 days earlier in Kanto and 2.5 days earlier in Hokkaido than photoperiod-sensitive cultivars. The lower effect of photoperiod-insensitive alleles observed in Hokkaido could be due to the longer day-length at the spike formation stage compared with that in Kanto. Pedigree analysis showed that ‘Purple Straw’ and ‘Tohoku 118’ were donors of Ppd-A1a and Ppd-D1a in Hokkaido wheat cultivars, respectively. Wheat cultivars recently developed in Hokkaido carry photoperiod-insensitive alleles at a high frequency. For efficient utilization of Ppd-1 alleles in the Hokkaido wheat-breeding program, the effect of Ppd-1 on growth pattern and grain yield should be investigated. Ppd-A1a may be useful as a unique gene source for fine tuning the heading time in the Tohoku-Kyushu region since the effect of Ppd-A1a on photoperiod insensitivity appears to differ from the effect of Ppd-B1a and Ppd-D1a.  相似文献   
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To study the mechanism of protogynous sex change in honeycomb grouper, the wild fish of both sexes and transitionals were collected for one year, and changes in gonadal structures and serum levels of sex hormones in each individual were examined. The onset of sex change was associated with low serum estradiol - 17β (E2) levels. In order to clarify whether E2 deprivation causes sex change, maturing females were implanted with the non-steroidal aromatase inhibitor (Fadrozole, AI). AI caused complete sex change from female to functional males in two and half months. The present results suggest that E2 is an important endogenous factor which regulates protogynous sex change in the honeycomb grouper.  相似文献   
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The in vitro reactivity of capsanthin (1) and fucoxanthin (2) with peroxynitrite was investigated, and the reaction products produced by scavenging with peroxynitrite were analyzed. (14'Z)-Nitrocapsanthin (3) and 12-nitrocapsanthin (4) were isolated from the products of the reaction of capsanthin with peroxynitrite. Similarly, (14Z)-15-nitrofucoxanthin (5), (11Z)-11-nitrofucoxanthin (6), and (14Z,9'Z)-15-nitrofucoxanthin (7) were obtained from the reaction of peroxynitrite reaction with fucoxanthin. Capsanthin and fucoxanthin inhibited the nitration of tyrosine by peroxynitrite. Furthermore, nitrocapsanthins (3 and 4) and nitrofucoxanthins (5 and 6) exhibited an inhibitory effect on Epstein-Barr virus early antigen activation in Raji cells and an antiproliferative effect on human pancreatic carcinoma. Moreover, nitrocapsanthins (3 and 4) inhibited carcinogensis of mouse skin tumors initiated by 7,12-dimethylbenz[a]anthracene (DMBN).  相似文献   
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Canine distemper virus (CDV) growth and the morphological characterization were examined in a cell line established from a canine malignant histiocytosis (CCT cell line). The susceptibility of the CCT cells to 3 CDV strains, FXNO, YSA-TC and MD-77 was shown by detection of the antigen in the indirect fluorescent assay. After passaging 4 and 9 times through the CCT cells, only FXNO strain could produce the syncytia where demonstrated the antigens. Titers of 9 passaged viruses through the CCT cells showed slightly higher in the CCT cells than those in Vero cells. Morphological characterization of karyorrhexis and specific DNA ladder by extracted DNA electrophoresis indicated apoptosis in the CDV infected CCT cells.  相似文献   
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As a part of the elucidation of the pathogenesis of anemia in Theileria sergenti infection, oxidized-erythrocyte membrane proteins (OEMPs) collected from T. sergenti-infected calves were examined. The amount of OEMPs were seen to increase with the progress of the anemia and showed a maximum value around the crisis period of the infection. The increase of OEMPs coincided with band Nos. 1, 2, 2.1, 3, 4.1, 5, 6, and 7. The majority of them was located at the Triton X-100 un-extractive phase, and was confirmed as cytoskeletal proteins. This evidence indicates the enhancement of erythrocytic oxidation, and suggests that it might be one of the aggravating factors of anemia in T. sergenti infection.  相似文献   
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