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81.
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
82.
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84.
Sugihara Y Sugisawa H Nakatani Y Hougham GW 《The journals of gerontology. Series B, Psychological sciences and social sciences》2004,59(4):P177-P184
This study examined how the psychological well-being of Japanese caregivers changed over time; it also examined the variation across kin relationships with care recipients. Three interviews over the course of 30 months were conducted with a representative sample of community-dwelling caregivers of frail elderly persons living in a Tokyo suburb. Latent growth modeling demonstrated that mean levels of both depression and emotional exhaustion worsened over time. Change in emotional exhaustion over time showed significant individual variability, whereas change in depression showed little individual variability. Although wife caregivers tended to experience the worst trajectory of emotional exhaustion, daughters-in-law also showed a similar negative trend. The difference in individuals' well-being trajectories by kinship may be explained partly by differences in care recipients' disabilities. 相似文献
85.
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
86.
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
87.
Takahisa Hirokawa Masashi Mimura Masahiro Tonari Yohei Sato Yasushi Fujita Junko Matsuo Hidehiro Oku Jun Sugasawa Tsunehiko Ikeda 《Medicine》2021,100(14)
Rationale:Enlargemento of the medial rectus is the most predominant factor of compressive optic neuropathy (CON) in Graves‘ disease. This case report indicates that CON could develop only from the hypertrophic superior levator and superior rectus (SL/SR) muscle in a patient with poorly controlled Graves‘ disease, and described the possible risk of FT3-thyrotoxicosis with a prominent goiter to develop the current rare case with a review of the literature.Patient concerns:A 66-year-old woman undergoing endocrine management of hyperthyroidism with prominent goiter visited the Department of Ophthalmology due to right-eye upper-eyelid retraction.Diagnoses:At initial presentation, the right and left margin reflex distance-1 (MRD-1) was 3.2 mm and 2.1 mm, respectively, and no proptosis or visual dysfunction was observed. Despite insufficient hormonal regulation, she refused to undergo goiter removal. The upper eyelid retraction gradually worsened to 7.7 mm of MRD-1, followed by the onset of 20 prism diopters (PD) of the right hypertropia, resulting in right-eye CON after 6 months. Her free thyroxin level was 3.88 ng/dl and free triiodothyronine was 24.90 pg/ml. Computed tomography and magnetic resonance imaging showed only SL/SR enlargement in the right orbit.Interventions:Intravenous steroid and radiation therapy resulted in visual improvement; however, a prominent upper eyelid retraction and 35PD of hypertropia remained in her right eye. Orbital decompression, upper retraction repair, and superior rectus recession were performed to prevent the recurrence of CON and correct any disfigurement.Outcomes:The combination of conventional intravenous steroid pulse therapy, radiotherapy, and orbital decompression was effective, and no recurrence was observed for more than 1.5-years postoperatively.Lessons:Enlargement of the SL/SR muscle complex may independently induce the CON. We believe that strict attention should be paid to patients with triiodothyronine thyrotoxicosis with progressive eyelid retraction and hypertropia. 相似文献
88.
Regulation of cell growth and expression of 7B2, PC2, and PC1/3 by TGFbeta 1 and sodium butyrate in a human pituitary cell line (HP75) 总被引:1,自引:0,他引:1
Recent studies have shown that 7B2 and the neuroendocrine-specific proconvertase PC2 have important roles in pituitary cell
proliferation and hormone secretion. Studies from our laboratory have also shown that TGFb1 regulates anterior pituitary cell
proliferation and hormone secretion.
To study the regulation of 7B2 in human pituitary tumors, we used a cell line derived from a human pituitary adenoma (HP75)
that has been shown to express 7B2, PC1, PC2, and TGFβ receptors to analyze the effects of TGFβ1 and the histone deacetylase
inhibitor (HDACI) sodium butyrate (NaB) treatment on 7B2 mRNA expression along with the neuroendocrine-specific proconvertases
1/3 (PC1) and PC2 mRNA and protein expression. RNA was quantified by real-time PCR and proteins were detected by immunohistochemistry
and Western blotting.
Treatment of cells with 1 mM NaB or 1 nM TGFβ1 for 4 d decreased cell proliferation with a concomitant increase in the cell cycle protein p21. Real-time PCR analysis
showed a significant increase in 7B2 mRNA after NaB and TGFβ1 treatment. PC2 mRNA was down regulated by NaB while PC1 mRNA
was unchanged. TGFβ1 stimulated PC1, but not PC2 mRNA levels. Changes in PC1 and PC2 protein were similar to changes in the
mRNAs, but the differences were not significant.
These results indicated that NaB and TGFβ1 inhibit pituitary cell proliferation and regulate the expression of 7B2, PC1, and
PC2 in a cell culture model of pituitary tumors. Our results also indicate that inhibition of pituitary cell proliferation
is associated with increased expression of 7B2 mRNA. 相似文献
89.
Telomerase activity and telomere length of peripheral blood mononuclear cells in SLE patients 总被引:4,自引:0,他引:4
Kurosaka D Yasuda J Yoshida K Yokoyama T Ozawa Y Obayashi Y Kingetsu I Saito S Yamada A 《Lupus》2003,12(8):591-599
We evaluated the clinical significance of the telomerase activity and telomere length of peripheral blood mononuclear cells (PBMC) in systemic lupus erythematosus (SLE). PBMC were isolated from 55 patients with SLE and the telomerase activity was measured by TRAP assay. The telomere length of PBMC was also measured in 30 of these subjects. As a control group, 45 healthy adults with no particular clinical history were studied. The results were compared with clinical data. In patients with active SLE, the telomerase activity of PBMC was significantly increased compared with the control group. In patients with inactive SLE, the PBMC telomerase activity was not different compared with the controls in their 20s, 30s and 40s, but it was significantly increased compared with the controls in their 50s. In SLE patients, the telomerase activity of PBMC was significantly correlated with modified SLEDAI. The telomere length of PBMC in younger SLE patients tended to be shorter than that in the controls, but no difference was observed in older patients. The correlation coefficient between the telomerase activity and telomere length of PBMC in SLE patients was not significant. Abnormalities in the telomerase activity and telomere length observed in SLE patients are considered to be important findings for evaluation of the pathology of SLE. 相似文献
90.
Akira Honda Tadashi Yoshida Naomi Tanaka Yasushi Matsuzaki Bingfang He Toshiaki Osuga M.D. Nobuaki Kobayashi Kazue Ozawa 《Journal of gastroenterology》1993,28(3):406-414
In Japan the composition of gallstones is changing rapidly from the once-predominant brownpigment stones to cholesterol ones.
The present work was undertaken to clarify the mechanism of cholesterol supersaturated bile production in Japanese patients
with cholesterol gallstones. In 26 non-obese and normolipidemic patients (11 with cholesterol gallstones, 8 with black- or
brown-pigment gallstones, 7 without gallstones) a liver biopsy and hepatic bile were surgically obtained under standardized
conditions. The cholesterol saturation of hepatic bile was significantly higher in cholesterol gallstone patients than in
gallstone-free controls (195 ±10 vs. 146 ±8%, respectively; P < 0.01). The microsomal activities of 3-hydroxy-3-methylglutaryl
coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme for cholesterol synthesis, cholesterol 7 α-hydroxylase, the rate-limiting
enzyme for bile acid synthesis, and 7 α-hydroxy-4-cholesten-3-one 12 α-hydroxylase (12 α-hydroxylase), the rate-limiting enzyme
for cholic acid synthesis, were assayed simultaneously in the same subjects. There were positive correlations between HMG-CoA
reductase and cholesterol 7 α-hydroxylase activities (Rs = 0.62, P < 0.005), and between cholesterol 7 α-hydroxylase and 12
α-hydroxylase activities (Rs = 0.44, P < 0.05) in all subjects, irrespective of the existence of gallstones. The activities
of the three rate-limiting enzymes did not differ significantly among the three groups (cholesterol stone, pigment stone and
stone-free). In conclusion, the cholesterol supersaturation of hepatic bile in nonobese and normolipidemic Japanese patients
with cholesterol gallstones does not result from an increased hepatic cholesterol synthesis or a decreased bile acid synthesis.
This study was supported in part by a Grant-in-Aid for Scientific Research (No. 02454226) from the Ministry of Education,
Science and Culture of Japan, and a grant from University of Tsukuba Project Research. 相似文献