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排序方式: 共有7064条查询结果,搜索用时 15 毫秒
91.
Daisuke Miyaki Hiroshi Aikata Yohji Honda Noriaki Naeshiro Takashi Nakahara Mio Tanaka Yuko Nagaoki Tomokazu Kawaoka Shintaro Takaki Koji Waki Akira Hiramatsu Shoichi Takahashi Masaki Ishikawa Hideaki Kakizawa Kazuo Awai Kazuaki Chayama 《Journal of gastroenterology and hepatology》2012,27(12):1850-1857
92.
Shibata T Fujimoto K 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(2):331-336
Because intracellular processes are inherently noisy, stochastic reactions process noisy signals in cellular signal transduction. One essential feature of biological signal transduction systems is the amplification of small changes in input signals. However, small random changes in the input signals could also be amplified, and the transduction reaction can also generate noise. Here, we show theoretically how the abrupt response of ultrasensitive signal-transduction reactions results in the generation of large inherent noise and the high amplification of input noise. The inherently generated noise propagates with amplification through intracellular molecular network. We discuss how the contribution of such transmitted noise can be shown experimentally. Our results imply that the switch-like behavior of signal transduction could be limited by noise; however, high amplification reaction could be advantageous to generate large noise, which would be essential to maintain behavioral variability. 相似文献
93.
Fluid shear stress generated by blood flowing over the endothelium is a major determinant of arterial tone, vascular remodeling, and atherogenesis. Nitric oxide (NO) produced by endothelial NO synthase (eNOS) plays an essential role in regulation of vascular function and structure by blood flow, but the molecular mechanisms that transduce mechanical force to eNOS activation are not well understood. In this study, we found that laminar flow (shear stress=12 dyne/cm2) rapidly activates vascular endothelial growth factor receptor 2 (VEGFR2) in a ligand-independent manner and leads to eNOS activation in cultured endothelial cells. Flow-stimulated VEGFR2 recruits phosphoinositide 3-kinase and mediates activation of Akt and eNOS. Inhibiting VEGFR2 kinase with selective inhibitors blocks flow-induced activation of Akt and eNOS and production of NO. Decreasing VEGFR2 expression with antisense VEGFR2 oligonucleotides significantly attenuates activation of Akt and eNOS. Furthermore, Src kinases are involved in flow-stimulated VEGFR2 because inhibiting Src kinases by PP2, a selective inhibitor for Src kinases, abolishes flow-induced VEGFR2 tyrosine phosphorylation and downstream signaling. Finally, we show that inhibiting VEGFR2 kinase significantly reduces flow-mediated NO-dependent arteriolar dilation in vivo. These data identify VEGFR2 as a key mechanotransducer that activates eNOS in response to blood flow. 相似文献
94.
Kotani A Takahashi A Koga H Morita R Fukuyama H Ichinohe T Ishikawa T Hori T Uchiyama T 《European journal of haematology》2002,69(5-6):318-320
A patient who developed myasthenia gravis (MG) 25 months after allogeneic bone marrow transplant was immunologically analyzed. OX40+CD4+ T cells in the peripheral blood prominently increased one month before the onset of MG. CD4/CD8 ratios, usually abnormally inverted in patients with chronic graft-vs.-host disease (cGVHD), showed pseudonormalization during the course of MG. We succeeded in uneventful rapid tapering of prednisolone (PSL) using mycophenolate mofetil (MMF). Monitoring of OX40+CD4+ T cells supported the tapering of PSL and MMF as a marker of cGVHD activity. This case suggested the utility of MMF and monitoring of OX40+CD4+ T cells in the management of cGVHD-associated autoimmune diseases. 相似文献
95.
96.
T. Iwamoto S. Nakahara R. Mibu M. Hotokezaka H. Nakano M. Tanaka 《Diseases of the colon and rectum》1997,40(11):1298-1298
97.
In vivo expression patterns of survivin and its splicing variants in chronic liver disease and hepatocellular carcinoma. 总被引:12,自引:0,他引:12
98.
99.
Zen Isobe Tatsuo Suga Toshimitsu Katou Kenichirou Hara Fumiaki Aoki Kana Aoyagi Manabu Ueno Toshitaka Maeno Masahiko Kurabayashi 《Nihon Kokyūki Gakkai zasshi》2008,46(3):226-231
A 54-year old man was admitted with general fatigue, muscle weakness and dyspnea on effort. Medical examinations led to a diagnosis of small cell lung carcinoma (SCLC) with Lambert-Eaton myasthenic syndrome (LEMS). Marked improvement of SCLC and symptoms of LEMS were recognized twice during chemoradiotherapy. On his third admission, he showed muscle weakness, dysaethesia, and neurodysfunction of the bladder and rectum. We initially considered these symptoms to be due to spinal metastasis because MRI findings showed multiple spinal metastases. However, electoromyogram and nerve conduction study demonstrated that his muscle weakness resulted from LEMS though dysethesia and neurodysfunction of bladder and rectum were caused by spinal metastasis. We believe that it is important to perform electomyogram and nerve conduction studies, not only radiographic findings, to detect the "hidden" symptoms of LEMS. 相似文献
100.
Zen Isobe Tatsuo Suga Yasuhiro Aoki Fumiaki Aoki Kana Ikeda Manabu Ueno Toshitaka Maeno Masahiko Kurabayashi 《Nihon Kokyūki Gakkai zasshi》2008,46(8):645-649
A 54-year old man was admitted to our hospital because of high fever, productive cough and purpura in both legs in June 2005. Urinalysis showed microscopic hematuria and proteinuria. Chest radiograph showed consolidation of right upper field. Because acid-fast bacilli and polymerase chain reaction test for Mycobacterium tuberculosis were positive in bronchial lavage fluid, we made a diagnosis of pulmonary tuberculosis, and prescribed antituberculosis therapy with isoniazid, rifampicin, ethambutol and pyrazinamide. In addition, anaphylactoid purpura was diagnosed by skin biopsy. In July 2005, renal function was deteriorated and nephrosis appeared. We treated with corticosteroid in addition to antituberculosis therapy. His symptoms and renal dysfunction improved. We report a rare case of an anaphylactoid purpura following occurence of pulmonary tuberculosis. 相似文献