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排序方式: 共有6641条查询结果,搜索用时 15 毫秒
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Tomohisa Furuya Satoru Sugimoto Chie Kurokawa Shuichi Ozawa Kumiko Karasawa Keisuke Sasai 《Journal of radiation research》2013,54(1):157-165
To evaluate the dosimetric impact of respiratory breast motion and daily setup error on whole breast irradiation (WBI) using three irradiation techniques; conventional wedge (CW), field-in-field (FIF) and irregular surface compensator (ISC). WBI was planned for 16 breast cancer patients. The dose indices for evaluated clinical target volume (CTVevl), lung, and body were evaluated. For the anterior-posterior (AP) respiratory motion and setup error of a single fraction, the isocenter was moved according to a sine function, and the dose indices were averaged over one period. Furthermore, the dose indices were weighted according to setup error frequencies that have a normal distribution to model systematic and random setup error for the entire treatment course. In all irradiation techniques, AP movement has a significant impact on dose distribution. CTVevlD95 (the minimum relative dose that covers 95 % volume) and V95 (the relative volume receiving 95 % of the prescribed dose) were observed to significantly decrease from the original ISC plan when simulated for the entire treatment course. In contrast, the D95, V95 and dose homogeneity index did not significantly differ from those of the original plans for FIF and CW. With regard to lung dose, the effect of motion was very similar among all three techniques. The dosimetric impact of AP respiratory breast motion and setup error was largest for the ISC technique, and the second greatest effect was observed with the FIF technique. However, these variations are relatively small. 相似文献
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Takashi Komatsu Hideaki Tachibana Yoshihiro Sato Mahito Ozawa Motoyuki Nakamura Ken Okumura 《Circulation journal》2007,71(1):46-51
BACKGROUND: It has been previously reported that the efficacy of class I antiarrhythmics in preventing the recurrence of symptomatic paroxysmal and persistent atrial fibrillation (AF) is limited when AF lasts for 48 h or more. However, it is unclear whether the efficacy of amiodarone, a class III drug, is superior to class I antiarrhythmics in patients with long-lasting AF. METHOD AND RESULTS: The relationship between the duration of tachycardia and the efficacy of amiodarone in preventing recurrence of tachycardia was examined in 55 patients (37 men, 18 women, mean age 68+/-9 years) to whom amiodarone was administered after electrical or pharmacological cardioversion for paroxysmal and persistent AF. In 26 patients, paroxysmal and persistent AF ceased within 48 h after onset (Group A), and in the other 29 patients, it ceased after 48 h (Group B). Patient characteristics and actuarial recurrence-free rates were compared between the 2 groups. The mean follow-up period was 30+/-11 months. No statistically significant difference between the groups was found in patient characteristics. Actuarial recurrence-free rates in Group A and B at 1, 3, 6, 9, and 12 months were 100%, 81%, 69%, 62%, and 54%, and 93%, 79%, 66%, 52%, and 48%, respectively (p=NS at 12 months). The period of maintenance of sinus rhythm was 14.7+/-3.2 months in group A and 13.3+/-3.3 months in group B (mean+/-SE, p=NS). CONCLUSION: In the case of amiodarone, efficacy for maintaining sinus rhythm after cardioversion of AF was not biased by the duration of arrhythmia. This observation suggests amiodarone is effective in maintaining normal sinus rhythm after cardioversion, even in patients with long-lasting AF and electrical atrial remodeling. 相似文献
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Takizawa M Nobuhisa I Igarashi K Ueno M Nakashima K Kitamura T Taga T 《Experimental hematology》2003,31(4):283-289
OBJECTIVE: Definitive hematopoiesis starts in the aorta-gonad-mesonephros (AGM) region during mouse development and remarkably expands in the liver at a later stage of ontogeny. gp130 is a signal transducing receptor component shared by all the IL-6 family cytokines, whose gene ablation in mouse results in the significant reduction in the fetal liver hematopoiesis. The present study aims to evaluate the role of gp130 signaling in the fetal mouse AGM hematopoiesis. METHODS AND MATERIALS: Mouse AGM regions from the wild-type and gp130-deficient mice on embryonic day 11.5 were dissociated and cultured with a mixture of cytokines, including one which activates gp130. Wild-type human gp130 and its mutant constructs were introduced into cultured gp130-deficient AGM cells using retrovirus system. To further analyze gp130 downstream signaling, a dominant-negative mutant of STAT3 was also introduced. RESULTS: The gp130 deficiency in the culture of fetal mouse AGM cells resulted in the failure of the expansion of the c-kit(+), Sca-1(+), and lineage markers(-) population. Such failure was rescued by introduction of a wild-type gp130 expression construct but not its mutant constructs having no ability to activate STAT3. In the normal AGM cell culture, introduction of a dominant-negative form of STAT3 in which Y(705) was changed to phenylalanine suppressed the expansion of hematopoietic cell colonies. CONCLUSION: gp130 plays an indispensable role in the expansion of hematopoietic precursor cells in the fetal mouse AGM. In particular, the activation of STAT3 by gp130 is found to be important in this process. 相似文献
99.
Tokura T Murase T Toriyama T Totani Y Negita M Akaza K Ozawa H Nakagawa A Nakamura S 《Internal medicine (Tokyo, Japan)》2003,42(1):105-109
A 57-year-old man was admitted with fever and epigastralgia, and presented with splenomegaly and pancytopenia. A CT scan revealed splenic infarctions. There were no lymphadenopathies, skin lesions, or neurological abnormalities. A splenectomy was performed. Bone marrow involvement with hemophagocytosis was noted. The diagnosis of Asian variant of intravascular diffuse large B-cell lymphoma was based on intravascular and sinusoidal distribution of large CD5+ B cells. The patient died of the disease 11 months after onset. To our knowledge, this is the first report of AIVL that presented with splenic infarction. This distinct lymphoma should be included in the differential diagnosis of splenic infarction. 相似文献
100.
Tomoyuki Asano Yuzuka Saito Naoki Matsuoka Jumpei Temmoku Yuya Fujita Kasumi Hattori Shunsuke Kobayashi Akira Ojima Toshiyuki Takahashi Haruki Matsumoto Makiko Yashiro-Furuya Shuzo Sato Hiroko Kobayashi Hiroshi Watanabe Kiori Yano Tomomi Sasajima Kazuo Fujihara Kiyoshi Migita 《Medicine》2021,100(15)
Rationale:Anti-myelin oligodendrocyte protein antibody-associated disease (MOGAD) is a new disease entity with various clinical phenotypes. MOGAD often present with recurrent optic neuritis (ON), and it can also develop as a compartment of neuromyelitis optica spectrum disorder (NMOSD). Moreover, multiple autoantibodies such as an anti-myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA) had been reported in the serum of patients with NMOSD.Patient concerns:We report an 86-year-old woman with a 2-year history of microscopic polyangiitis (MPA). The patient had a rapid loss of vision in her left eye. No abnormal findings were observed on her left fundus, and she tested negative for MPO-ANCA upon admission. However, anti-MOG antibodies were observed in the patient''s serum and cerebrospinal fluid.Diagnosis:A diagnosis of MOGAD complicated with MPA was made.Interventions:The patient received twice steroid pulse therapy and oral azathioprine as maintenance therapy.Outcomes:Her vision rapidly recovered, and no subsequent relapse was observed during the 8-month observation period.Conclusion:To the best of our knowledge, this is the first case of MOGAD complicated with MPA, and steroid pulse therapy and azathioprine therapy were effective for ON caused by MOGAD. 相似文献