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排序方式: 共有890条查询结果,搜索用时 31 毫秒
1.
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
2.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
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Evaluation of a new enzyme-linked immunosorbent assay test for rotavirus antigen in faeces 总被引:6,自引:0,他引:6 下载免费PDF全文
A new commercial test for the diagnosis of rotavirus gastroenteritis was assessed. With some modifications it compared favourably with electron microscopy and immunofluorescence. 相似文献
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.
Keratinocyte growth factor is an important endogenous mediator of hair follicle growth, development, and differentiation. Normalization of the nu/nu follicular differentiation defect and amelioration of chemotherapy-induced alopecia. 总被引:8,自引:5,他引:8 下载免费PDF全文
D. M. Danilenko B. D. Ring D. Yanagihara W. Benson B. Wiemann C. O. Starnes G. F. Pierce 《The American journal of pathology》1995,147(1):145-154
The growth and development of hair follicles is influenced by a number of different growth factors and cytokines, particularly members of the fibroblast growth factor (FGF) family. Keratinocyte growth factor (KGF or FGF-7) is a recently identified 28-kd member of the FGF family that induces proliferation of a wide variety of epithelial cells, including keratinocytes within the epidermis and dermal adnexa. Because KGF induces marked proliferation of keratinocytes, and both KGF and KGF receptor (KGFR) mRNA are expressed at high levels in skin, we sought to localize KGF and KGFR in skin by in situ hybridization. KGFR mRNA was relatively strongly expressed by keratinocytes in the basilar epidermis as well as throughout developing hair follicles of rat embryos and neonates. KGF mRNA was expressed at lower levels than was KGFR but could be localized to follicular dermal papillae in rat embryos and neonates. These results prompted us to investigate the effects of KGF on hair follicles in two distinct murine models of alopecia. In the first model, recombinant KGF (rKGF) induced dose-dependent hair growth over most of the body in nu/nu athymic nude mice when administered intraperitoneally or subcutaneously over 17 to 18 days. When administered subcutaneously, rKGF induced the most extensive hair growth at the sites of injection. Histologically, rKGF induced marked follicular and sebaceous gland hypertrophy, a normalization of the nu/nu follicular keratinization defect, and an increase in follicular keratinocyte proliferation as assessed by bromodeoxyuridine labeling. In the second model, a neonatal rat model of cytosine arabinoside chemotherapy-induced alopecia in which interleukin-1, epidermal growth factor, and acidic FGF have all demonstrated some degree of alopecia cytoprotection, rKGF induced a dose-dependent cytoprotective effect, abrogating as much as 50% of the alopecia in this model when administered beginning 1 day before the onset of chemotherapy. Taken together, these data suggest that KGF is an important endogenous mediator of normal hair follicle growth, development, and differentiation. 相似文献
8.
Fgf-10 is required for both limb and lung development and exhibits striking functional similarity to Drosophila branchless 总被引:11,自引:1,他引:11 下载免费PDF全文
Hosung Min Dimitry M. Danilenko Sheila A. Scully Brad Bolon Brian D. Ring John E. Tarpley Margaret DeRose W. Scott Simonet 《Genes & development》1998,12(20):3156-3161
Fgf-10-deficient mice (Fgf-10−/−) were generated to determine the role(s) of Fgf-10 in vertebrate development. Limb bud initiation was abolished in Fgf-10−/− mice. Strikingly, Fgf-10−/− fetuses continued to develop until birth, despite the complete absence of both fore- and hindlimbs. Fgf-10 is necessary for apical ectodermal ridge (AER) formation and acts epistatically upstream of Fgf-8, the earliest known AER marker in mice. Fgf-10−/− mice exhibited perinatal lethality associated with complete absence of lungs. Although tracheal development was normal, main-stem bronchial formation, as well as all subsequent pulmonary branching morphogenesis, was completely disrupted. The pulmonary phenotype of Fgf-10−/− mice is strikingly similar to that of the Drosophila mutant branchless, an Fgf homolog. 相似文献
9.
10.
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