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861.
862.
Shuhei Fujii Ryoichi Yamamoto Kensuke Miyamoto Junichi Ueda 《Phycological Research》1997,45(4):223-226
The occurrence of jasmonic acid and related compounds in Dunaliella species was investigated using gas-liquid chromatography/mass spectroscopy (GCY MS). Jasmonic acid was identified in the ethyl acetate soluble-acidic fraction of Dunaliella tertiolecta and Dunaliella salina (Dunal) Teodoresco, The concentration of jasmonic acid in D. salina. which is extremely halophilic, was much higher than that in D. tertiolecta Butcher, These results indicate that jasmonic acid might play an important role in salt-tolerance in Dunaliella. 相似文献
863.
Nakabayashi Kazuhiko; Ogata Toshihiko; Fujii Michihiko; Takahashi Ei-ichi; Ogino Hideki; Michishita Eriko; Scherer Stephen W.; Tsui Lap-Chee; Ayusawa Dai 《DNA research》1996,3(3):181-183
Mouse A9 cells containing human chromosome 7 tagged with pSV2neowere irradiated with X-rays and fused to A9 cells to isolateG418-resistant clones. From these clones, we selected radiationhybrids that contained 1040 Mb of human DNA apparentlyat a single site of their genome by FISH analysis using humanrepetitive sequences as a probe. Then we made a panel of hybridsthat contained various fragments of the 7q31-q32 region andcover its entire region altogether by PCR with STS markers ofhuman chromosome 7. This panel is useful in chromosome transferexperiments since the dominant selective marker neo gene isattached to human DNA. 相似文献
864.
Yoshiyuki Tohno Masako Utsumi Setsuko Tohno Takeshi Minami Yuko Okazaki Yumi Moriwake Fumio Nishiwaki Masa-oki Yamada Tadashi Fujii Yoshinori takakura 《Biological trace element research》1997,60(1-2):81-90
To elucidate age-related change of mineral contents in human bones, the mineral content and density of human calcanei were
determined by inductively coupled plasma atomic emission spectrometry and dual-energy X-ray absorptiometry. Calcanei were
removed from 27 subjects (17 men and 10 women) who died in the age range from 40–98 yr old.
Both the inductively coupled plasma emission spectrometry and dual-energy X-ray absorptiometry indicated that there were agedependent
decreases of the mineral contents and density in the men’s calcaneus in the age range from 40–98 yr, but not in the women’s
calcaneus in the age range from 42–87 yr. It was also found that the calcanean masses of the men and women remained constant
within the same age range until 98 yr. 相似文献
865.
Metabolic inactivation of retinoic acid by a novel P450 differentially expressed in developing mouse embryos. 总被引:9,自引:2,他引:7
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H Fujii T Sato S Kaneko O Gotoh Y Fujii-Kuriyama K Osawa S Kato H Hamada 《The EMBO journal》1997,16(14):4163-4173
Retinoic acid (RA) is a physiological agent that has a wide range of biological activity and appears to regulate developmental programs of vertebrates. However, little is known about the molecular basis of its metabolism. Here we have identified a novel cytochrome P450 (P450RA) that specifically metabolizes RA. In vitro, P450RA converts all-trans RA into 5,8-epoxy all-trans RA. P450RA metabolizes other biologically active RAs such as 9-cis RA and 13-cis RA, but fails to metabolize their precursors, retinol and retinal. Overexpression of P450RA in cell culture renders the cells hyposensitive to all-trans RA. These functional tests in vitro and in vivo indicate that P450RA inactivates RA. The P450RA gene is not expressed uniformly but in a stage- and region-specific fashion during mouse development. The major expression domains in developing embryos include the posterior neural plate and neural crest cells for cranial ganglia. The expression of P450RA, however, is not necessarily inducible by excess RA. These results suggest that P450RA regulates the intracellular level of RA and may be involved in setting up the uneven distribution of active RA in mammalian embryos. 相似文献
866.
Y Ishii T Hoson S Kamisaka K Miyamoto J Ueda S Mantani S Fujii Y Masuda R Yamamoto 《Biological Sciences in Space》1996,10(1):3-7
The life cycle of Arabidopsis plants was examined by growing them on a horizontal clinostat. Seeds on agar media were allowed to germinate and seedlings were grown under a simulated microgravity on a horizontal clinostat. Clinorotation (3 rpm) did not appear to interfere with germination of plant seeds and development of cotyledons and leaves. Stress relaxation parameters of the cell wall, the minimum relaxation time and the relaxation rate did not appear to be affected by clinostat rotation. On the other hand, the length of inflorescences was reduced to 61-62% by clinostat rotation. Rotation was found to inhibit the polar transport of auxin, although inflorescence growth and auxin transport were not completely inhibited. From these facts, it is possible that the life cycle in Arabidopsis plants could be accomplished in space, although growth phenomena involving auxin transport and its action may be disturbed. Plants may have a capacity to grow in space and we may be able to cultivate crops in space. 相似文献
867.
We have recently (Kawakami et al, Immunol. Lett. 1995;46: 143) demonstrated that unusual Mac-1+CD4?CD8? T cells bearing αβ antigen receptor (Mac-1+ αβ T cells) reside in a considerable proportion in murine lungs. The present study was performed to examine the dynamics of accumulation of these cells in the lungs following intravenous administration of Mycobacterium bovis BCG (BCG). Mac-1+ αβ T cells accumulated rapidly 24 hr after infection, followed by a gradual increase over the observation period of 15 days. Furthermore, the expression of Ia, ICAM-1 and FcγR II/III on their surface intensified dramatically after BCG infection. The kinetics of enhancement of Ia expression was slower than that of ICAM-1, with the maximum level attained in one day in the latter molecule but in two weeks in the former. Neutralization of endogenous IFN-γ by specific mAb completely blocked the augmented expression of Ia on Mac-1+ αβ T cells after BCG infection, but did not have any significant effect on that of ICAM-1. In contrast, in vivo administration of IFN-γ enhanced the expression of ICAM-1 as well as that of Ia. Our results indicate that accumulation of Mac-1 αβ T cells within the lung is associated with a differential change in the expression of surface antigens, and suggest that these cells may play a role in the host defense against mycobacterial infection. 相似文献
868.
869.
Hiroshi Isogai Koichi Kimura Shunji Hayashi Toru Kubota Nobuhiro Fujii Takeshi Nishikawa Satoshi Kotake Emiko Isogai 《Microbiology and immunology》1997,41(5):427-430
This study describes the levels of interleukin-1 alpha (IL-1α), tumor necrosis factor alpha (TNFα) and interleukin-6 (IL-6) in the sera and parenchymal organs of various congenic mouse strains infected with Borrelia garinii. A significant elevation of inflammatory cytokine levels was found in the organs of C3H/HeN (H-2k) and B10.BR (H-2k) mice but not in those of BALB/c mice (H-2d). Focally produced cytokines can contribute to antimicrobial defense against these organisms. High levels of IL-1α were observed in the sera of C3H/HeN, B10.BR and B10 (H-2b) mice infected with B. garinii and they were associated with the presence of spirochetes in the skin. Thus, susceptible mice demonstrated a stronger cytokine response than resistant mice. This study presents in vivo evidence that B. garinii infection affects the immunopathogenesis of Lyme disease. 相似文献
870.
Use of a fusion protein to obtain crystals suitable for X-ray analysis: crystallization of a GST-fused protein containing the DNA-binding domain of DNA replication-related element-binding factor, DREF. 总被引:4,自引:2,他引:2
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M. Kuge Y. Fujii T. Shimizu F. Hirose A. Matsukage T. Hakoshima 《Protein science : a publication of the Protein Society》1997,6(8):1783-1786
Crystals of glutathione-S-transferase (GST)-fused protein containing the DNA-binding domain of DNA replication-related element-binding factor, DREF, were obtained under crystallization conditions similar to those for GST. Preliminary X-ray crystallographic analysis revealed that crystals of the GST-fused protein belong to space group P6(1)22 or P6(5)22 with unit cell dimensions a = b = 140.4 A, c = 93.5 A and gamma = 120 degrees, having one molecule in the crystallographic asymmetric unit. The crystals diffract to 2.5 A resolution. The cell dimensions are related to those of GST crystals thus far reported. Crystallization of the DNA-binding domain that was cleaved from the fused protein by thrombin was also carried out using several methods under numerous conditions, but efforts to produce well-ordered large crystals were unsuccessful. A possible application of GST-fusion proteins for small target proteins or domains to obtain crystals suitable for X-ray structure determination is proposed. 相似文献