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排序方式: 共有7083条查询结果,搜索用时 31 毫秒
81.
82.
A novel Fc receptor for IgA and IgM is expressed on both hematopoietic and non-hematopoietic tissues
Sakamoto N Shibuya K Shimizu Y Yotsumoto K Miyabayashi T Sakano S Tsuji T Nakayama E Nakauchi H Shibuya A 《European journal of immunology》2001,31(5):1310-1316
By contrast to well-defined Fc gamma and Fc epsilon receptors, the structural and functional characteristics of Fc mu receptor are unclear. We have recently described a novel mouse Fc receptor, designated Fc alpha/mu receptor, and its human homologue, which bind both IgM and IgA. Here we show that the Fc alpha/mu receptor is expressed on mature, but not immature, B lymphocytes and acquires the ability to bind IgM and IgA antibodies after stimulation of B lymphocytes. Moreover, stimulation with phorbol 12-myristate 13-acetate increased endocytosis of IgM-coated microparticles mediated by the Fc alpha/mu receptor expressed on pro-B cell line Ba/F3 cells. We also show that the Fc alpha/mu receptor is expressed in secondary lymphoid organs, such as lymph node and appendix, kidney and intestine, suggesting an important role of the receptor for immunity in these organs. 相似文献
83.
Hiroyuki Shibuya Norio Azumi Yoshikazu Onda Fumihiko Abe 《Pathology international》1985,35(1):157-164
A case of multicentric malignant fibrous histiocytoma of the stomach and small intestine is reported. The patient was a 60-year-old man who had total gastrectomy under an impression of a gastric carcinoma. The resected stomach revealed a large polypoid mass in the antral portion at the greater curvature. Three months later, he developed ileus and an 80 cm segment of the jejunum was removed. It contained two polypoid masses identical to that seen in the stomach. The tumors showed, in addition to the characteristic light microscopic appearances, strong positivity for alpha-1-antitrypsin by an immunoperoxidase technique, indicating the diagnosis of malignant fibrous histiocytoma (MFH). Electron microscopic findings were also consistent with MFH. We believe that this is the first well-documented case of MFH arising from the stomach and small intestine, to the best of our knowledge. 相似文献
84.
Hoshina M Shibuya H Kubo HD Miura M Ohashi I Yoshimura R Oota S 《Medical physics》2004,31(7):2068-2074
A new characterization of depth-ionization parameters for electron beams is empirically deduced from our data analysis based on the divided difference method (the DD method), which employs the numerical differential of an ionization curve. The important feature of the present method is that it does not necessarily require normalized percent depth-ionization (NPDI) data. The depth of 50% of maximum ionization, I50, which is an important parameter for electron beam dosimetry, can be deduced from the analysis of an unnormalized (or partial) depth-ionization (UDI) curve obtained over a short interval of depth. The values of I50 determined by the DD method are in agreement to within 0.1 mm for energies of 4, 6, and 9 MeV, compared with the ones determined by the TG-51 protocol method (or the conventional method), and the difference was 0.9 mm for 12 and 15 MeV. The dose at the reference depth, dref, calculated from I50 by the DD method, is found to be in agreement with TG-51 to within 0.1%. The field size dependence of the DD method using UDI data was studied for three field sizes: 6 x 6, 10 x 10, and 20 x 20 cm2. For all energies, the discrepancies of I50 as determined by both methods were 0.9 mm on average for the 6 x 6 cm2 fields and 0.6 mm for the other two field sizes. This dependence was remarkable for 6 x 6 cm2 fields for 12 and 15 MeV, and the discrepancies shown by the DD method were 1.2 mm for 12 MeV and 1.8 mm for 15 MeV, respectively. Since the reference field size in clinical dosimetry is usually 10 x 10 cm2, this dependence will not affect clinical dosimetry. The DD method could be an alternative option for checking beam quality in dose calibration. 相似文献
85.
86.
Acupuncture has been practiced in the treatment of many diseases in Japan. "Okibari" is one of the procedures in acupuncture treatment: a fine stainless steel or silver needle is inserted into the subcutaneous tissue through the skin, to remain in the subcutaneous tissue. A 57-year-old pharmacist was knocked down by a motorcycle in 1971, since then moderate weakness of left extremities and stiffness of muscles have remained as sequelae. She was consequently treated with acupuncture. Many small needles were inserted permanently in the nuchal, occipital and other areas of the body ten to twelve years before she developed gradual clumsiness and dysesthesia in her right hand in 1984. When she was admitted for the first time in 1985, neurological examination revealed left Horner's syndrome and diminished deep sensation in her right extremities with pseudo-athetosis of her right hand, along with spastic paresis of left extremities and right carpal tunnel syndrome. An old needle which had strayed into left dorsal medulla was considered to be responsible for these symptoms. In 1988 loss of pain and temperature sensation in the right side of her body below the shoulder, and diminished deep sensation of left extremities were appended, and weakness of her left extremities became aggravated. Pseudo-athetosis of her right hand was seen less prominently. In plain X-ray films many needle shadows were visualized. On CT scan needle shadows could be seen also in the left dorsal medulla, right cerebellum and in the subarachnoid space of left dorsal C1-C2 level.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
87.
目的 :测定类风湿性关节炎病人足底压 ,评价足底板的生物力学效应。方法 :12名女性类风湿性关节炎病人和 8名健康女性进行年龄和体重匹配。用 F- Scan系统进行动态足底压测量 ,Kistler床反力平台用以校正测量精确性。测量足底峰压和垂直分力 ,评价足底板的生物力学表现。结果 :类风湿性关节炎病人中足底压明显高于健康人。使用足底板后 ,足底总的峰压明显降低 ,前足、后足峰压减低 ,中足峰压增高。而垂直分力改变不大。结论 :足底板能显著降低足底压力 ,使足底压力重分布 ,减轻类风湿足痛。特殊设计的足底板对类风湿足痛的治疗能起重要的作用 相似文献
88.
Takanori Ito Taishi Takahara Natsuki Taniguchi Yuki Yamamoto Akira Satou Akiko Ohashi Emiko Takahashi Naoto Sassa Toyonori Tsuzuki 《Pathology international》2023,73(11):542-548
Clinical and genomic features of prostate cancer (PCa) vary considerably between Asian and Western populations. PTEN loss is the most frequent abnormality in intraductal carcinoma of the prostate (IDC-P) in Western populations. However, its prevalence and significance in Asian populations have not yet been well studied. In the present study, we evaluated PTEN expression in IDC-P in a Japanese population and its association with ERG expression. This study included 45 and 59 patients with PCa with and without IDC-P, respectively, who underwent radical prostatectomy. PTEN loss was observed in 10 patients with PCa with IDC-P (22%) and nine patients with PCa without IDC-P (17%). ERG expression was relatively frequent in patients with PCa with PTEN loss, although a significant difference was not observed. The co-occurrence of PTEN loss and ERG expression was observed in four patients with PCa with IDC-P and one without IDC-P. PTEN loss and ERG expression did not affect progression-free survival, regardless of the presence of IDC-P. The frequency of PTEN loss in IDC-P is lower in Asian patients than in Western patients. Our results indicate that mechanisms underlying IDC-P in Asian populations are different from those of Western populations. 相似文献
89.
Nomizu T Tsuchiya A Kanno M Katagata N Watanabe F Yamaki Y Abe R Miki Y 《Breast cancer (Tokyo, Japan)》1997,4(4):239-242
The possible role of germline mutations ofBRCA1 andBRCA2 as causative agents of familial breast cancer was assessed. Their possible involvement in the carcinogenesis of hereditary
breast cancer was investigated using 63 clinically suspect families. Twenty-one lineages (33.3%) had mutations in one of the
twoBRCA genes. This relatively low incidence suggested that germline mutations in unknown genes are involved in the carcinogenesis
of hereditary breast cancer in the Japanese population. However, the clinicopathological features characteristic of hereditary
breast cancer, such as early disease onset, a high incidence of bilateral breast cancer, and a high incidence of multiple
primary carcinomas in other organs were confirmed in the present study. 相似文献
90.
Moriya Hidetaka Maitani Yoshie Shimoda Naoto Takayama Kozo Nagai Tsuneji 《Pharmaceutical research》1997,14(11):1621-1628
Purpose. Recombinant human erythropoietin (Epo) is used frequently through intravenous (i.v.) and subcutaneous (s.c.) administration for the clinical treatment of the last stage of renal anemia. We encapsulated Epo in liposomes to develop an alternative administration route. The purpose of our study was to evaluate the pharmacokinetics and the pharmacological effects of liposomal Epo in comparison with the Epo after i.v. and s.c. administration to rats.
Methods. Epo was encapsulated in liposomes composed of dipalmitoylphosphatidylcholine (DPPC) and soybean-derived sterol mixture (SS) prepared by the reversed-phase evaporation vesicle method. After filtration through a 0.1 m polycarbonate membrane, liposomes were gel filtered (Epo/liposomes).
Results. Epo/liposomes showed higher pharmacological activity than Epo/liposomes before gel filtration after i.v. administration to rats. Non-encapsulated Epo lost its activity, whereas encapsulated Epo in liposomes retained it. The pharmacological effects of Epo/liposomes were greater than those of Epo after i.v. administration. Epo/liposomes afforded 3–9 times higher AUC, lower clearance and lower steady-state volume of distribution than Epo after both i.v. and s.c. administrations. Epo/liposomes had an improved pharmacokinetic profile compared with Epo. S.c. administration of Epo/liposomes at 7 h may penetrate primarily (40% of dose) through the blood as a liposome and partly (7% of dose) in lymph.
Conclusions. Epo/liposomes may reduce the frequency of injections required for a certain reticulocyte effect in comparison to Epo. The lower clearance of Epo/liposomes may increase the plasma concentrations of Epo, which increases the efficacy. 相似文献