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排序方式: 共有830条查询结果,搜索用时 0 毫秒
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2.
Akira Sawaki Nobumasa Mizuno Kuniyuki Takahashi Tsuneya Nakamura Masahiro Tajika Hiroki Kawai Toshifumi Isaka Hiroshi Imaoka Yasuyuki Okamoto Masatoshi Aoki Hiroyuki Inoue Ahmed AS Salem Yasushi Yatabe Kenji Yamao 《Digestive endoscopy》2006,18(1):40-44
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed. 相似文献
3.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
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6.
Competitive control of the self-renewing T cell repertoire 总被引:1,自引:0,他引:1
We develop a mathematical model for the self-renewing part of the T cell
repertoire. Assuming that self-renewing T cells have to be stimulated by
immunogenic MHC-peptide complexes presented on the surfaces of
antigen-presenting cells, we derive a model of T cell growth in which
competition for MHC-peptide complexes limits T cell clone sizes and
regulates the total number of self-renewing T cells in the animal. We show
that for a sufficient diversity and/or degree of cross-reactivity, the
total T cell number hardly depends upon the diversity of the T cell
repertoire or the diversity of the set of presented peptides. Conversely,
for repertoires of lower diversity and/or cross-reactivity, steady-state
total T cell numbers may be limited by the diversity of the T cells. This
provides a possible explanation for the limited repertoire expansion in
some, but not all, mouse T cell re-constitution experiments. We suggest
that the competitive interactions described by our model underlie the
normal T cells numbers observed in transgenic mice, germ-free mice and
various knockout mice.
相似文献
7.
Zhang Y Siebert R Matthiesen P Harder S Theile M Scherneck S Schlegelberger B 《Virchows Archiv : an international journal of pathology》2000,436(3):271-275
For the first time, combined immunophenotyping and fluorescence in situ hybridization (FISH) technique according to the ”fluorescence
immunophenotyping and interphase cytogenetics as a tool for investigation of neoplasms” (FICTION) technique have been successfully
applied in solid tumors. Thus, we were able to visualize the antigen expression of cells with chromosomal deletions of a tumor
suppressor region directly. In six breast carcinoma cell lines, we investigated the correlation between estrogen receptor
(ER) expression status and deletions of the estrogen receptor gene (ESR). To screen for deletions of the ESR gene, dual-color
FISH was performed with a YAC (yeast artificial chromosome) probe containing the ESR gene and, as internal control, with a
centromeric probe of chromosome 6. Deletions of the ESR gene were detected in four of six cell lines. For direct comparison
of ER expression with the copy number of the ESR gene at the single cell level, immunophenotyping with mouse anti-human ER
antibody was combined with FISH with the YAC probe containing the ESR gene according to the FICTION technique. There was no
correlation between lack of or reduced ER expression and deletions of the ESR gene. One cell line with deletions of the ESR
gene did express ER on the protein level, while another cell line without a deletion did not. Cells with deletions of the
ESR gene were either ER expression positive or negative. The staining intensity of ER expression was not associated with the
copy number of the ESR gene. Thus, this FICTION study unequivocally shows that deletions of the ESR gene are not the major
cause of absent or reduced ER expression in breast carcinoma cell lines.
Received: 6 September 1999 / Accepted: 14 September 1999 相似文献
8.
Spontaneous secretion of interleukin-4, interleukin-10 and interferon-gamma by first trimester decidual mononuclear cells 总被引:4,自引:0,他引:4
Ekerfelt C Lidström C Matthiesen L Berg G Sharma S Ernerudh J 《American journal of reproductive immunology (New York, N.Y. : 1989)》2002,47(3):159-166
PROBLEM: A T-helper cell type 2 (Th2) cytokine dominated microenvironment has been predicted to be crucial for successful pregnancy. However, little information is available about local cytokine secretion in the human decidua. We determined the spontaneous secretion of interleukin-4 (IL-4), interferon-gamma (IFN-gamma) and IL-10 by decidual mononuclear cells at the single cell level and compared it with their secretion by peripheral blood mononuclear cells (PBMC) in the first trimester of pregnancy. METHODS OF STUDY: The cytokine secretion from decidual and blood cells was detected by a sensitive enzyme-linked immunosorbent spot-forming cell (ELISPOT)-assay. RESULTS: Cells secreting IL-4 (median 153, range 8-530), IL-10 (median 188, range 32-1600) and IFN-gamma (median 123, range 15-1140) were detected in all decidual and blood samples. The cytokine secretion showed a co-linear pattern in both the blood and decidua, i.e. when one cytokine was secreted at high levels, the others followed the trend. No correlation was found between the number of cytokine secreting cells in blood and decidua for any of the cytokines. CONCLUSIONS: Interleukin-4 and IL-10 are locally secreted in the decidua early during normal pregnancy, probably counteracting the fetal rejecting effects of co-expressed IFN-gamma. The cytokine secretion by blood cells does not generally reflect the local secretion pattern during first trimester pregnancy. 相似文献
9.
Survey of CAG/CTG repeats in human cDNAs representing new genes: candidates for inherited neurological disorders 总被引:3,自引:2,他引:3
Neri C; Albanese V; Lebre AS; Holbert S; Saada C; Bougueleret L; Meier-Ewert S; Le Gall I; Millasseau P; Bui H; Giudicelli C; Massart C; Guillou S; Gervy P; Poullier E; Rigault P; Weissenbach J; Lennon G; Chumakov I; Dausset J; Lehrach H; Cohen D; Cann HM 《Human molecular genetics》1996,5(7):1001-1009
10.