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排序方式: 共有5318条查询结果,搜索用时 625 毫秒
51.
52.
Nidhi Sharma Atsushi Ohyabu Yoshiki Murakumo Masahide Takahashl Mitsuhiro Saito Hiroyuki Amo Shin-ichiro Murayama Kyoko Ohno Sen-ichi Oda Mutsushi Matsuyama 《Pathology international》1997,47(7):436-441
The thymoma prone BUF/Mna (B) rat is a useful model for Studying the genes responsible for thymus enlargement during the stage of young growth. Among the strains of rats, B rats have the largest thymuses at al stages of life. A locus, Ten-1 , which contributes to thymus enlargement in back-cross (BC) rats between the B and WKY/NCrj (W) strains, was mapped on chromosome 1. To determine the precise location of the bus, (B×(B×MITE)F1) BC rats were generated by crossing the B strain with the Inbred MITE (M) strain, which was established from captured, Japanese wild rats, and were examined by linkage study using polymerase chain reaction with 67 microsatellite markers. Linkages with thymus enlargements were found In genotypes of seven markers, BSIS, LSN, MYL2, IGF2, PBPC2, D1Mgh11 , and D1Mit6 , by X2- test and Student's t -test, which confirmed the presence of the genetic locus associated with thymus enlargement, Ten-1 , in this region. Paradoxically, a suppressive locus, Tsu-1 , to thymus enlargement was also found on chromosome 3, showing linkages of phenotype of the small thymus with genotypes of SCN2A, CAT D3Mit16 , and D3Mit13 . By analyses of mapmaker/exp and mapmaker/qtl, Ten-1 was mapped at 4.6 cM proximal from IGF2 locus on chromosome 1 and Tsu-1 at 4.0 cM proximal from CAT locus on chromosome 3, respectively. 相似文献
53.
Saijo Y Ohashi T Sasaki H Sato M Jorgensen CS Nitta S 《Annals of biomedical engineering》2001,29(12):1048-1053
Scanning acoustic microscopy (SAM) was equipped to assess the acoustic properties of normal and atherosclerotic coronary arteries. The SAM image in the atherosclerotic lesion clearly demonstrated that the sound speed was higher than that in the normal intima, and that the variation of elasticity was found within the fibrous cap of the plaque. Young's elastic modulus of each region was calculated and the finite element analysis was applied to derive the stress distribution in these arterial walls. In a case of normal coronary artery, the stress was dominant in the intima and the distribution was rather homogeneous and in a case of atherosclerosis, high stress was concentrated to the relatively soft lesion in the fibrous cap overlying lipid pool. SAM provides information on the physical properties, which cannot be obtained by the optical microscope. The results would help in understanding the pathological features of atherosclerosis. © 2001 Biomedical Engineering Society.
PAC01: 8764-t, 8763Df, 8719Xx, 8719Rr 相似文献
54.
Shin-ichiro Shoda Akio Komenoi Tomochika Fujioka Yasunori Okumura Shiro Kobayashi 《Macromolecular chemistry and physics.》1996,197(2):633-640
Isopropoxyethyne (1a) and tert-butoxyethyne (1b) were polymerized using group 5 and 6 transition metal catalysts to give poly(isopropoxyethyne) (2a) and poly(tert-butoxyethyne) (2b) , respectively. The weight-average molecular weight (M?w) of the resulting poly(alkoxyethyne)s was up to 1.0 × 104. Among the transition metal catalysts, a tungsten alkoxide or a molybdenum alkoxide having low Lewis acidity were found to effectively promote the polymerization without causing side reactions. Poly(tert-butoxyethyne) was successfully converted to poly(β-ketone) 3 by acid hydrolysis of the tert-butyl vinyl moiety. 相似文献
55.
Kennichi Kakudo Akira Miyauchi Shin-ichiro Takai Shoichi Katayama Kanji Kuma Hajime Kitamura 《Pathology international》1979,29(4):653-659
Two cases of papillary type of C cell carcinoma of the thyroid were reported. They showed papillary arrangement with Abrovascular stalk in properly Axed tissues. Histochemically argyrophil reaction was positive in the cytoplasm and amyloid deposited in the stroma. Ultrastructurally secretory granules were found in their cytoplasm. The papillary type is not an artifact but one of the histologic variations of this carcinoma. ACTA PATH. SAP. 29: 653–659, 1979. 相似文献
56.
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58.
Transgenic Mice as an in vivo Model for Self-Reactivity 总被引:1,自引:0,他引:1
Davto A. Ferrick Pamela S. Ohashi Valerie A. Wallace Marco Schilham Tak W. Mak 《Immunological reviews》1990,118(1):257-283
59.
Kawauchi S Okuda S Morioka H Iwasaki F Fukuma F Chochi Y Furuya T Oga A Sasaki K 《Human pathology》2005,36(10):1096-1100
Large cell neuroendocrine carcinoma (LCNEC) of the uterine cervix is a newly introduced category of the revised World Health Organization classification. We reported a case of cervical LCNEC with cytogenetic analysis by comparative genomic hybridization (CGH). The cervical tumor showed moderately increased mitotic activity (8-14 mitotic figures per 10 high-power fields) and focal necrosis, which made it problematic to differentiate from atypical carcinoid. CGH analysis failed to detect chromosome 11q loss that has been reported to be characteristic of pulmonary atypical carcinoids. Furthermore, chromosome 3q amplification, which has been detected frequently in pulmonary small cell carcinomas and LCNECs but not in pulmonary typical and atypical carcinoids, was the most remarkable chromosomal aberration. Although CGH reports are extremely rare in neuroendocrine tumors of the uterine cervix, specific chromosomal aberrations may be useful in their distinction. 相似文献
60.
Morimoto-Tomita M Ohashi Y Matsubara A Tsuiji M Irimura T 《Clinical & experimental metastasis》2005,22(6):513-521
Highly metastatic variants of mouse colon 38 colon carcinoma cells were established by repeated selection in vivo for liver metastasis and designated as SL4 cells. The SL4 cells formed colonies in the liver of 100% of syngenic mice when
injected intrasplenically, while the incidence of liver metastasis was 27% of mice injected with parental cells. The weight
of livers, which is an indicator of experimental hepatic metastasis formation, was significantly higher after intrasplenic
injection and subsequent splenoctomy with SL4 cells than colon 38 cells. The incidence of hepatic metastasis after intracecal
injection of SL4 cells was significantly higher than that of colon 38 cells. The SL4 cells were tested in vitro for their properties. Differences were not detected in the motility and invasive behavior between colon 38 cells and SL4
cells. SL4 cells showed a higher proliferation rate than colon 38 cells under adherent conditions. SL4 cells maintained a
capacity to proliferate under non-adherent conditions whereas parental cells did not. SL4 cells should be a useful tool to
study the mechanism of hepatic metastasis of colon carcinoma cells and to develop methods to prevent hepatic metastasis. 相似文献