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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
3.
Kamalesh Das Gouranga Prosad Mondal Ashok Kumar Dutta Bijoy Mukherjee Bansi Badan Mukherjee 《Journal of clinical neuroscience》2007,14(1):12-16
Awareness among the general population of the risk factors and warning symptoms of stroke is essential for preventative purposes and for immediate effective treatment. The aim of the present study was to assess the awareness, among the general population and stroke survivors, of the risk factors and warning symptoms of stroke, to develop an educational strategy for its prevention and immediate effective treatment. Six hundred and sixty stroke patients (370 male, 290 female) and 4000 people from the general population who accompanied the patients (2800 male, 1200 female) were interviewed, using three sets of questionnaires, on the risk factors and warning symptoms of stroke. Poor knowledge or awareness of the risk factors and warning symptoms of stroke was found in both groups. Both groups suggested educational programs for stroke using printed information, audiovisual programs and community survey programs using simple and understandable information for the prevention and immediate effective treatment of stroke. Poor awareness of stroke contributes to a delay in the arrival of patients in hospital emergency departments for immediate effective treatment. Multifaceted programs regarding stroke, including printed information, audiovisual programs and stroke service programs, are advocated by both patients and the general population to improve stoke treatment and prevention. 相似文献
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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
8.
W. Ken Busfield Ian M. G. Cowie M. A. Sattar Mondal 《Macromolecular chemistry and physics.》1979,180(7):1775-1786
Two series of block copolymers have been synthesized comprising of soft polytrifluoroacetaldehyde (polyacetal) segments and of hard 4,4′-methylenedi(phenyl isocyanate)/cis-cyclohexane-1,4-diol polyurethane segments. The series-A copolymers in which the soft segments were directly bound to the hard segments had significantly lower thermal stability than the series-B copolymers in which the soft segments were linked to the hard segments by sebacic ester units. In both series the thermal stability decreased with increasing soft segment content. The series-A copolymers exhibited two thermal transitions both characteristic of Tg's and separated by about 60 K. In contrast the series-B copolymers exhibited two characteristic Tg's separated by 200–250 K, depending on composition, together with an additional endothermic transition at about ambient temperature. All transitions for both series decreased with increasing soft segment content. The observations have been compared with those of other polyether and polyester based polyurethanes. 相似文献
9.
An Indian isolate of Goatpox virus (GTPV) was adapted and propagated in Vero cells for development of an attenuated virus. The virus was initially passaged in primary lamb testes cells and subsequently in Vero cells. At the 55th passage, the virus showed evidence of attenuation when tested for safety in seronegative goats. At this stage, the virus was found to be completely non-pathogenic. The virus was passaged further and the 60th passage was used for testing its immunogenicity in goats. The latter were inoculated with 10, 100 and 1000 TCID50 of the attenuated virus by intradermal (i.d.) route and challenged after 28 days with virulent GTPV. The attenuated virus produced no adverse reaction even at the highest dose and conferred complete protection even at the lowest dose against challenge with a high dose (2 x 10(6) of 50% skin-reactive dose SRD50) of virulent virus. Increased levels of virus-specific serum antibodies could be demonstrated by both indirect enzyme-linked immunosorbent assay (ELISA) and virus neutralization (VN) test in all the immunized goats. No horizontal transmission of the virus from the immunized to in-contact animals took place. Our results suggest that this attenuated virus could be a safe, immunogenic and potent candidate for developing a vaccine against goatpox. 相似文献
10.
Sharma R Mondal A Sahoo M Kakar A Shankar LR Khanna CM Chopra MK Soni NL 《The Journal of the Association of Physicians of India》1999,47(5):488-491
One hundred and forty eight subjects with euthyroid solitary thyroid nodules (STN) were taken up for radionuclide perfusion study. They were found to have a cold STN on 99mTc thyroid static scan. All had fine needle aspiration cytology (FNAC), and except for subjects with chronic lymphocytic thyroiditis, were subjected to surgery for tissue diagnosis by histopathology. The diagnostic findings in these patients of solitary thyroid nodules were correlated with the histopathology. Radionuclide perfusion study is considered useful to differentiate benign from malignant cold thyroid solitary nodules with high degree of sensitivity (95%) and specificity (87.9%). 相似文献