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991.
(?)-Kaur-16-en-19-oic acid and tetrachyrin, a new rearranged kaurenoid lactone, were isolated from Tetrachyron orizabaensis var. websteri and Helianthus debilis ssp. debilis. The latter species also afforded angeloylgrandifloric acid. 相似文献
992.
Shin Tanaka Sachi Kuwahara Kazutoshi Nishijima Yasunori Nakamura Yasunori Sumi Tamio Ohno Nobuo Goto 《Experimental Animals》2006,55(5):433-438
The shape of the mandible was compared by morphometric methods to ascertain the genetic differences between two substrains of F344 rats, F344/DuCrlCrlj and F344/NSlc. Since these two substrains are clearly different in survival and the incidence of age associated disorders; thus, some genetic differences are suggested to be present between them. Although previous microsatellite analysis did not detect any differences between the two F344 substrains, the present study clearly detected interesting differences in the mandible morphology. At 2 months of age, the F344/Du mandible was characterized by a larger size, especially in length, than the F344/N mandible. The shape of the mandible seemed to be more variable in F344/N. This clear substrain difference suggests the importance of the substrain recognition in F344 rats, especially in experimental usage. 相似文献
993.
Shin Tanaka Sachi Kuwahara Kazutoshi Nishijima Tamio Ohno Masahiro Nagaya Yasunori Nakamura Yasunori Sumi Osamu Miyaishi Hiroaki Aoyama Nobuo Goto 《Experimental Animals》2006,55(5):415-418
The characteristics of the mandible bone were compared through DXA methods between two major substrains of F344 rats, F344/DuCrlCrlj and F344/NSlc at around 60 days of age. Since these two substrains are clearly different in survival and mandible morphology, some genetic differences are supposed to exist. In contrast to a previous microsatellite analysis, clear and significant differences were detected in the body and mandible weights, the mandible bone mineral contents (BMC), bone area (AREA), bone mineral density (BMD) and bone mineral ratio (BMR), between F344/DuCrlCrlj and F344/NSlc, with the mandible molar teeth intact in the bone. Thus, care is needed in the experimental use of these substrains, as results may differ between them. The newly proposed parameter, BMR, may especially contribute to the comparison of bone characteristics among species. 相似文献
994.
Shigeru Sugaya Kazuko Kita Hideoki Fukuoka Nobuo Suzuki 《Biological Sciences in Space》2004,18(3):167-168
Head-down-tilt bed rest (BR) is utilized to mimic a microgravity environment. In this study, we examined whether the modulating activity of serum factors on cell mutability was changed in seventeen volunteers subjected to BR. For comparison, serum was comparatively obtained from seven volunteers who experienced the parabolic flight (PF). Cultured human cells were treated with serum and then irradiated with UV or X-ray. Mutagenicity was estimated by identification of K-ras codon 12 base substitution mutation, following PCR and differential dot-blot hybridization. Modulating activity was detected in one sample from each of post-BR and post-PF serum. 相似文献
995.
Nishimatsu H Takeuchi T Ueki T Kajiwara T Moriyama N Ishida T Li B Kakizoe T Kitamura T 《Cancer immunology, immunotherapy : CII》1999,48(1):56-61
The CD95/CD95 ligand (CD95L) system plays an important role in the induction of lymphoid apoptosis and has been implicated
in the suppression of immune responses. In this system, two murine CD95L-transfected renca clones and a control renca clone
transfected only with the vector were implanted into the subcapsule of the left kidney of Balb/c and Balb/c nude mice. Both
CD95L-expressing and control renca clones formed macroscopic tumors in all of the Balb/c and Balb/c nude hosts 14 days after
implantation. Growth of tumors of murine CD95L-transfected renca cells was significantly better than that of control renca
cells in Balb/c mice, while the growth advantage of CD95L transfectants was not observed in Balb/c nude mice. Lymphocytes
underwent apoptosis mainly in the periphery of the CD95L-expressing tumors but not in control tumors grown in Balb/c mice,
while lymphocytes undergoing apoptosis were not observed in CD95L-expressing tumors or in control tumors grown in Balb/c nude
mice. Neutrophilic recruitment was rarely observed in CD95L-expressing or control tumors. CD95L expressed on renca cells possibly
suppressed immune responses against renca tumors by inducing apoptosis of the infiltrating lymphocytes. However, CD95L-expressing
renca cells did not form tumors in the renal subcapsule of allogeneic C3H/HeJ mice.
Received: 23 July 1998 / Accepted: 23 December 1998 相似文献
996.
Co-induction of nitric oxide and tetrahydrobiopterin synthesis in the myocardium in vivo 总被引:3,自引:0,他引:3
Hattori Yoshiyuki Hattori Sachiko Motohashi Satoshi Kasai Kikuo Shimoda Shin-Ichi Nakanishi Nobuo 《Molecular and cellular biochemistry》1997,166(1-2):177-181
Induction of the inducible isoform of nitric oxide (NO) synthase (iNOS) in the myocardium is implicated as a mechanism in the development of cardiac depression in immune activated states associated with an enhanced release of cytokines, such as septic shock. We evaluated the in vivo synthesis of NO and tetrahydrobiopterin (BH4), a cofactor of NOS, in the heart tissue using a model of LPS injection in rats (LPS: 10 mg/kg, i.v.). In control rats, iNOS activity or iNOS mRNA in the heart was negligible. Three hours after LPS administration, a marked induction of iNOS mRNA and activity was observed in the heart. A significant increase in BH4 content and GTP cyclohydrolase mRNA abundance was also observed in the heart from LPS-treated rats. Our results demonstrate induction of NO synthesis and parallel increase in BH4 concentration in the heart of rats after LPS treatment in vivo and may provide molecular evidence responsible for the increased production of BH4 which may up-regulate iNOS activity in the heart in vivo. (Mol Cell Biochem 166: 177-181, 1997) 相似文献
997.
Nobuo Kido Naoki Morooka Noriko Paeng Taizo Ohtani Hidemitsu Kobayashi Nobuyuki Shibata Yoshio Okawa Shigeo Suzuki Tsuyoshi Sugiyama Takashi Yokochi 《Microbiology and immunology》1997,41(7):519-525
A monoclonal antibody (mAb) with a unique antigenic specificity against Escherichia coli O9 was produced. The O9a mAb was reactive with a part of the strains in E. coli O9. The O9a mAb did not react with LPS from the E. coli O9 test strain Bi316-42. The distribution of the antigen defined by the O9a mAb in E. coli O9 was consistent with that of E. coli O9a present in E. coli O9 strains. The chemical structure of the repeating unit of the O-specific polysaccharide detected by the mAb was demonstrated to be a mannotetraose by two-dimensional nuclear magnetic resonance spectroscopy. It was confirmed that the mAb recognized E. coli O9a serotype in E. coli O9 serotype strains, suggesting that E. coli O9a serotype might be a dominant strain in E. coli O9. 相似文献
998.
999.
Prediction of the Coding Sequences of Unidentified Human Genes. VIII. 78 New cDNA Clones from Brain Which Code for Large Proteins in vitro 总被引:2,自引:0,他引:2
1000.
Nobuo Moriyama Shigeharu Kurimoto Kazuki Kawabe Kuniaki Takata Hiroshi Hirano 《Journal of molecular histology》1997,29(4):273-278
Glucose transporters (GLUTs) are a family of membrane proteins responsible for the transport of glucose across cellular membranes.
In terms of their mRNA levels, they have been reported to be expressed in some human tumours. However, the immunohistochemical
localization of GLUTs in human urogenital lesions has rarely been studied. This study was performed to evaluate the expression
of GLUT1 in penile proliferative lesions (18 cases of penile carcinoma and 13 cases of condyloma acuminatum). Using an isoform-specific
anti-GLUT1 antibody, formalin-fixed paraffin-embedded sections were stained by the avidin--biotin complex method. In all cases
of penile carcinoma, GLUT1 staining was diffusely recognized on the cell membrane of the carcinoma cells in the mainly infiltrating
areas. However, the inner areas of the tumour were more weakly and focally stained. The intensity of staining for the penile
carcinoma (staining score = 2.8 ± 0.6) was stronger than that for condyloma acuminatum and that for adjacent non-proliferative
areas. All cases of condyloma acuminatum showed a diffuse staining on the cell membrane in the basal and intermediate layers
(staining score = 2.4 ± 0.5). Non-proliferative (histologically normal) glans areas adjacent to the above lesions expressed
the weakest GLUT1 staining only in the stratum basale (staining score = 1.8 ± 0.5). These three areas showed significantly
different staining scores from each other (p 0.01). In conclusion, GLUT1 is expressed dominantly in penile proliferative lesions,
especially in infiltrating areas of penile carcinoma 相似文献