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排序方式: 共有811条查询结果,搜索用时 15 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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A. Y. Massele C. Kilewo Y. Aden Abdi G. Tomson V. K. Diwan Ö. Ericsson G. Rimoy L. L. Gustafsson 《European journal of clinical pharmacology》1997,52(4):299-305
Objective: Routine malaria prophylaxis with chloroquine (CQ) is recommended to pregnant semi-immune women in several countries in Africa.
The dosage is empirically based. We investigated whether blood CQ concentrations and apparent oral blood clearance (CL/F)
change during the course of pregnancy. We also studied whether malaria parasites could be detected together with low CQ blood
levels.
Methods: Forty nine semi-immune Tanzanian women were recruited in the 16th week of pregnancy. They were given 310 mg oral CQ base
once per week as prophylaxis during the whole pregnancy. Capillary blood samples were taken for analysis of CQ before treatment
and at weeks 26 and 36. Blood samples were dried on filter paper and analysed by HPLC. Blood was also drawn to detect occurrence
of malaria parasites.
Results: A total of 25 women fulfilled the sampling schedule. CL/F increased significantly from 160 ml · min−1 at week 26 to 180 ml · min−1 at week 36. In 7 of 25 women, CL/F increased >20%. Trough blood CQ concentrations, determined on four occasions at week 26
and at week 36 varied between 200 and 900 nmol · l−1. No statistically significant differences between occasions were seen. Malaria parasites were seen in two individuals early
in pregnancy.
Conclusion: Blood CQ CL/F showed a small increase during the course of pregnancy. The estimated mean blood CL/F values of 160 and 180 ml · min−1 (week 26 and 36, respectively) were higher than the mean CL/F of 125 ml · min−1 in non-pregnant individuals, published previously. Efficacy of higher dosages of CQ in malaria prophylaxis in pregnant women
could, therefore, be evaluated in controlled trials in high-risk malaria areas.
Received: 3 July 1996 / Accepted in revised form: 5 November 1996 相似文献
7.
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
8.
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
9.
Meng Q Walker DM Scott BR Seilkop SK Aden JK Walker VE 《Environmental and molecular mutagenesis》2004,43(2):75-92
A multiplex PCR procedure for analysis of genomic DNA mutations in the mouse hypoxanthine-guanine phosphoribosyltransferase (Hprt) gene was developed and then used with other established methods for the coincident identification of large- and small-scale genetic alterations in the Hprt gene of mutant T-cell isolates propagated from sham- and 1,3-butadiene (BD)-exposed mice and rats. The spectra data for RT-PCR/cDNA analysis and multiplex PCR of genomic DNA from Hprt mutants were combined, and statistical analyses of the mutant fractions for the classes of mutations identified in control versus exposed animals were conducted. Under the assumption that the mutant fractions are distributed as Poisson variates, BD exposure of mice significantly increased the frequencies of (1) nearly all types of base substitutions; (2) single-base deletions and insertions; and (3) all subcategories of deletions. Significantly elevated fractions of G:C-->C:G and A:T-->T:A transversions in the Hprt gene of BD-exposed mice were consistent with the occurrence of these substitutions as the predominant ras gene mutations in multiple tumor types increased in incidence in carcinogenicity studies of BD in mice. BD exposure of rats produced significant increases in (1) base substitutions only at A:T base pairs; (2) single-base insertions; (3) complex mutations; and (4) deletions (mainly 5' partial and complete gene deletions). Future coincident analyses of large- and small-scale mutations in rodents exposed to specific BD metabolites should help identify species differences in the sources of deletion mutations and other types of mutations induced by BD exposures in mice versus rats. 相似文献