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Luan Shu Zi- Chun Hua 《中国药理通讯》2006,23(3):30-30
Triptolide is potent immunosuppressive has been reported to inhibit autoimmunity, compound isolated from Chinese herbal medicine. Triptolide allograft attributed to the suppression of T cells via NF - kB rejection and GVHD, and its efficacy was previously pathway and apoptosis. In the present study, we detailedly analyzed Triptolide' s function on murine primary T cell. We found that Triptolide could inhibit T cell activation and proliferation by dramatically down - regulating cell division and cell cycle. Triptolide inhibited T cell activation in a dose- dependent manner, and the inhibition was mediated by both NF- kB pathway and AP - 1 pathway. 相似文献
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Seung Min Lee Seung Kyung Hann Soo II Chun Seung Hung Lee Yoon-Kee Park 《The Journal of dermatology》1994,21(2):106-110
A 25-year-old female has had brown to erythematous telangiectatic patches and grouped papules on her face, neck, arm, and trunk since childhood following B.C.G. vaccination. Histopathologically, the lesions consisted of hyperkeratosis, slight acanthosis, tuberculoid granulomas with some Langerhans type giant cells in the mid-dermis. Although various forms of cutaneous tuberculosis after B.C.G. vaccination have been reported, it was difficult for us to assign the patient's skin lesion to any specific disease entity. Remission of her cutaneous lesions occurred clinically and histopathologically after treatment with isoniazid and rifampin. 相似文献
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Performance measurement of the microPET focus 120 scanner. 总被引:6,自引:0,他引:6
Jin Su Kim Jae Sung Lee Ki Chun Im Su Jin Kim Seog-Young Kim Dong Soo Lee Dae Hyuk Moon 《Journal of nuclear medicine》2007,48(9):1527-1535
The microPET Focus 120 scanner is a third-generation animal PET scanner dedicated to rodent imaging. Here, we report the results of scanner performance testing. METHODS: A (68)Ge point source was used to measure energy resolution, which was determined for each crystal and averaged. Spatial resolution was measured using a (22)Na point source with a nominal size of 0.25 mm at the system center and various off-center positions. Absolute sensitivity without attenuation was determined by extrapolating the data measured using an (18)F line source and multiple layers of absorbers. Scatter fraction and counting rate performance were measured using 2 different cylindric phantoms simulating rat and mouse bodies. Sensitivity, scatter fraction, and noise equivalent counting rate (NECR) experiments were repeated under 4 different conditions (energy window, 250 approximately 750 keV or 350 approximately 650 keV; coincidence window, 6 or 10 ns). A performance phantom with hot-rod inserts of various sizes was scanned, and several animal studies were also performed. RESULTS: Energy resolution at a 511-keV photopeak was 18.3% on average. Radial, tangential, and axial resolution of images reconstructed with the Fourier rebinning (FORE) and filtered backprojection (FBP) algorithms were 1.18 (radial), 1.13 (tangential), and 1.45 mm full width at half maximum (FWHM) (axial) at center and 2.35 (radial), 1.66 (tangential), and 2.00 mm FWHM (axial) at a radial offset of 2 cm. Absolute sensitivities at transaxial and axial centers were 7.0% (250 approximately 750 keV, 10 ns), 6.7% (250 approximately 750 keV, 6 ns), 4.0% (350 approximately 650 keV, 10 ns), and 3.8% (350 approximately 650 keV, 6 ns). Scatter fractions were 15.9% (mouse phantom) and 35.0% (rat phantom) for 250 approximately 750 keV and 6 ns. Peak NECR was 869 kcps at 3,242 kBq/mL (mouse phantom) and 228 kcps at 290 kBq/mL (rat phantom) at 250 approximately 750 keV and 6 ns. Hot-rod inserts of 1.6-mm diameter were clearly identified, and animal studies illustrated the feasibility of this system for studies of whole rodents and mid-sized animal brains. CONCLUSION: The results of this independent field test showed the improved physical characteristics of the F120 scanner over the previous microPET series systems. This system will be useful for imaging studies on small rodents and brains of larger animals. 相似文献
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Yasushi Nishihira Chun‐Feng Tan Junko Hirato Junichi Yoshimura Kenichi Nishiyama Hideaki Takahashi Yukihiko Fujii Hitoshi Takahashi 《Neuropathology》2007,27(6):551-555
Two embryonal CNS tumors, atypical teratoid/rabdoid tumor (AT/RT) and primitive neuroectodermal tumor (PNET), may be confused with each other and misdiagnosed. Here we report an infant with a congenital supratentorial tumor, which was detected by fetal MRI at 37 weeks gestation. On routine histological examination, the tumor was composed mainly of small undifferentiated cells, among which many rhabdoid cells and occasional sickle‐shaped embracing cells were observed. No mesenchymal or epithelial areas were evident. Our impression was that the tumor was an atypical example of AT/RT. Immunohistochemically, almost all the tumor cells were strongly positive for vimentin. However, epithelial membrane antigen was notably negative, and most of the tumor cell nuclei were clearly positive for INI1. In addition, many tumor cells were positive for neurofilament protein. There were also occasional small areas containing many tumor cells positive for glial fibrillary acidic protein. Finally, a diagnosis of PNET, with a rhabdoid phenotype and expression of neuronal and glial markers, was made. In the present case, application of INI1 immunostaining was very helpful for distinguishing PNET from AT/RT. 相似文献
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We report a patient who developed tension pneumopericardium following penetrating trauma to the chest. Lung adhering to the pleura due to previous infection prevented the lung from collapsing and resulted in diversion of the air leak into the anterior mediastinum and from there through a breach into the pericardium. 相似文献
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寒冷干燥地区平时火器伤的早期处理 总被引:3,自引:3,他引:0
目的 探讨寒冷干燥地区平时火器伤伤情特点与早期救治方法。方法 对 1991年 1月— 2 0 0 2年 12月间 40例火器伤病人的临床救治进行回顾分析。结果 2 4例枪伤中 ,2 0例一期缝合伤口 ,均一期愈合 ,另外 4例只清创未一期缝合的伤口 ,3例愈合 ,1例感染 ;4例骨折内固定均愈合良好 ,无骨髓炎发生。 16例炸伤病人局部软组织损伤及污染比枪弹伤重 ,14例一期缝合伤口中 ,10例一期愈合 ,4例感染 ,骨折内固定 2例 ,均愈合良好 ,无骨髓炎发生。结论 寒冷干燥地区火器伤早期伤道清创时限可适当延长 ,在平时火器伤的救治中 ,对软组织条件较好的创面 ,早期清创后可一期闭合伤口和骨折内固定 ,这样可减少感染和伤残 ,促进康复 相似文献