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51.
Incidence of human parvovirus B19 DNA detection in blood donors 总被引:2,自引:0,他引:2
Yuko Yoto Tooru Kudoh Keiji Haseyama Nobuhiro Suzuki Takanori Oda Toshiaki Katoh Tsuneo Takahashi Sadami Sekiguchi Shunzo Chiba 《British journal of haematology》1995,91(4):1017-1018
Summary. 1000 serum samples from blood donors were tested for human parvovirus B19 (B19) DNA by a nested PCR assay: six samples were positive for B19 DNA. The frequency was 1/167 (0-6%), considerably higher than previous surveys (0-004-0-03%). Five of the six samples were also positive for anti-B19 IgM, indicating an acute phase of infection. It is recommended to screen for B19 DNA in blood products to prevent transfusion mediated viral infection for those susceptible such as immunocompromised patients and pregnant women. 相似文献
52.
Toshitaro Nakagawa Sachiko Matozaki Tohru Murayama Ryuichiro Nishimura Masayoshi Tsutsumi Ryuji Kawaguchi Yasunobu Yokoyama Kazumasa Hikiji Takashi Isobe Kazuo Chihara 《British journal of haematology》1993,85(3):469-476
Summary. A cell line designated SKM-1 was newly established from leukaemic cells of a 76-year-old Japanese male patient with monoblastic leukaemia following myelodysplastic syndrome (MDS). The cells were obtained from peripheral blood of the patient when he lost multiple point mutations of ras genes with acquisition of chromosomal abnormalities during disease progression in MDS. The cells grew as a single floating cell, and have been continuously growing with the morphological characteristics of immature monoblasts by serial passages during the past 42 months with a doubling time of about 48 h. By cytochemical analysis. the cloned cells were positive for butyrate esterase, but negative for the Epstein-Barr virus associated nuclear antigen. Phenotypic analysis revealed the expression of myelomonocyte specific antigens such as CD4, CD13, CD33 and HLA-DR. Cells from the primary peripheral blood and those from SO passages of the SKM-1 cell line both possessed no activated ras genes but showed karyotype abnormalities with 46.XY, del(9)(q13;q22), der(17) t(17:?)(p13:?). The SKM-1 cells have two mutations in p53 gene and overexpress the pS3 products. This cell line may contribute to a better understanding of molecular mechanisms in the progression from MDS to myelogenous leukaemia. 相似文献
53.
Yazawa T Uesaka M Inaoka Y Mizutani T Sekiguchi T Kajitani T Kitano T Umezawa A Miyamoto K 《Endocrinology》2008,149(4):1786-1792
We have shown previously that Cyp11b1, an 11beta-hydroxylase responsible for glucocorticoid biosynthesis in the adrenal gland, was induced by cAMP in androgen-producing Leydig-like cells derived from mesenchymal stem cells. We found that Cyp11b1 was induced in male Leydig cells, or female theca cells, when human chorionic gonadotropin was administered in immature mice. Expression of Cyp11b1 in rodent gonads caused the production of 11-ketotestosterone (11-KT), a major fish androgen, which induces male differentiation or spermatogenesis in fish. As in teleosts, plasma concentrations of 11-KT were elevated in human chorionic gonadotropin-treated mice. In contrast to teleosts, however, plasma concentrations of 11-KT were similar in both sexes, despite levels of testosterone, a precursor substrate, being about 20 times higher in male mice. Because expression of 11beta-hydroxysteroid dehydrogenase type 2, was much higher in the mouse ovary than in the testis, conversion of testosterone into 11-KT may occur more efficiently in the ovary. In a luciferase reporter system that was responsive to and activated by androgens, 11-KT efficiently activated mammalian androgen receptor-mediated transactivation. Our results suggest that the androgen metabolic pathway is conserved between teleosts and mammals, despite sexual dominance and reproductive functions of 11-KT being altered during evolution. 相似文献
54.
Restoration of ultraviolet-induced unscheduled DNA synthesis of xeroderma pigmentosum cells by the concomitant treatment with bacteriophage T4 endonuclease V and HVJ (Sendai virus). 总被引:9,自引:7,他引:9 下载免费PDF全文
K Tanaka M Sekiguchi Y Okada 《Proceedings of the National Academy of Sciences of the United States of America》1975,72(10):4071-4075
Ultraviolet (UV)-induced unscheduled DNA synthesis of xeroderma pigmentosum cells, belonging to complementation groups A, B, C, D, and E, was restored to the normal level by concomitant treatment of the cells with T4 endonuclease V and UV-inactivated HVJ (Sendai virus). The present results suggest that (1) T4 endonuclease molecules were inserted effectively into the cells by the interaction of HVJ with the cell membranes, (2) the enzyme was functional on human chromosomal DNA which had been damaged by UV irradiation in the viable cells, (3) all the studied groups of xeroderma pigmentosum ("variant" was not tested) were defective in the first step (incision) of excision repair. 相似文献
55.
Masahiro Yakami Akira Yamamoto Morio Yanagisawa Hiroyuki Sekiguchi Takeshi Kubo Kaori Togashi 《Journal of digital imaging》2013,26(3):419-426
The purpose of this study is to verify objectively the rate of slice omission during paging on picture archiving and communication system (PACS) viewers by recording the images shown on the computer displays of these viewers with a high-speed movie camera. This study was approved by the institutional review board. A sequential number from 1 to 250 was superimposed on each slice of a series of clinical Digital Imaging and Communication in Medicine (DICOM) data. The slices were displayed using several DICOM viewers, including in-house developed freeware and clinical PACS viewers. The freeware viewer and one of the clinical PACS viewers included functions to prevent slice dropping. The series was displayed in stack mode and paged in both automatic and manual paging modes. The display was recorded with a high-speed movie camera and played back at a slow speed to check whether slices were dropped. The paging speeds were also measured. With a paging speed faster than half the refresh rate of the display, some viewers dropped up to 52.4 % of the slices, while other well-designed viewers did not, if used with the correct settings. Slice dropping during paging was objectively confirmed using a high-speed movie camera. To prevent slice dropping, the viewer must be specially designed for the purpose and must be used with the correct settings, or the paging speed must be slower than half of the display refresh rate. 相似文献
56.
57.
Yasunobu Yamashita MD Jun Kato MD PhD Kazuki Ueda MD PhD Yasushi Nakamura MD PhD Hiroko Abe MD Takashi Tamura MD Masahiro Itonaga MD Takeichi Yoshida MD PhD Hiroki Maeda MD Kosaku Moribata MD PhD Toru Niwa MD PhD Takao Maekita MD PhD Mikitaka Iguchi MD PhD Hideyuki Tamai MD PhD Masao Ichinose MD PhD 《Journal of clinical ultrasound : JCU》2015,43(2):89-97
58.
59.
Moroi Masaaki; Jung Stephanie M.; Nomura Shosaku; Sekiguchi Sadayoshi; Ordinas Antonio; Diaz-Ricart Maribel 《Blood》1997,90(11):4413-4424
60.
Early effects of lafutidine or rabeprazole on intragastric acidity: which drug is more suitable for on-demand use? 总被引:4,自引:0,他引:4
Inamori M Togawa J Iwasaki T Ozawa Y Kikuchi T Muramatsu K Chiguchi G Matsumoto S Kawamura H Abe Y Kirikoshi H Kobayashi N Shimamura T Kubota K Sakaguchi T Saito S Ueno N Nakajima A 《Journal of gastroenterology》2005,40(5):453-458
Background Medication for the relief of heartburn should have the rapid onset of action required for on-demand use. We studied the inhibition of gastric acid secretion by lafutidine and rabeprazole, given in single doses to fasting and postprandial subjects.Methods A total of 22 healthy male, Helicobacter pylori-negative volunteers participated in this randomized, two-way crossover study. They were randomly assigned to receive a single oral dose of 10mg lafutidine or 20mg rabeprazole after fasting overnight (12 subjects, fasting study) or after eating a test meal (noodles, 364kcal; protein, 10.1g; fat, 16g; carbohydrates, 44.9g; NaCl, 1.1g; 10 subjects, postprandial study). Intragastric pH was monitored continuously for 6h after treatment. The other drug was given after a washout period of at least 7 days, and intragastric pH was similarly monitored.Results In the fasting study, lafutidine sustained pH at >3 and >4 during the second, third, fourth, fifth, and sixth hours of the study for significantly longer than rabeprazole. During the first 6h after treatment, lafutidine sustained pH at more than 2, 3, 3.5, 4, 5, 6, and 7 longer than rabeprazole. In the postprandial study, lafutidine sustained pH >3 and >4 for longer periods than rabeprazole during the third, fourth, fifth, and sixth hours of the study. During the first 6h after treatment, lafutidine sustained pH at more than 2, 3, 3.5, 4, 5, 6, and 7 longer than rabeprazole.Conclusions Lafutidine 10mg produces a prompter rise in intragastric pH than rabeprazole 20mg in fasting and postprandial Helicobacter pylori-negative male subjects. 相似文献