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排序方式: 共有4098条查询结果,搜索用时 15 毫秒
51.
52.
Nickel titanium (NiTi) foams were made by combustion synthesis of powders with the help of ZrH2 as foaming agent and TiB2 as endothermic agent. In this paper, we investigated the effect of elemental powder size on the foaming. The powder size of Ni and Ti affected the ignition temperature of the combustion reaction, cell morphology and microstructure of the foams. The cell morphology of the foams was also modified by the powder size of TiB2. 相似文献
53.
Akiko Chino Teruhito Kishihara Naoyuki Uragami Akiyoshi Ishiyama Taishi Ogawa Etsuo Hoshino Masahiro Igarashi Rikiya Fujita 《Digestive endoscopy》2009,21(1):56-58
The present patient developed a severe rectal ulcer more than 1 month after having received external beam radiation therapy for prostate cancer. Surveillance endoscopy every 3 months demonstrated healing of this rectal ulcer using a novel therapy. He was given enemas with ecabet sodium, which provides physical protection and promotes healing by increasing prostaglandin E2, and this process induced squamous metaplasia that halted the progression of the ulcer of radiation proctitis as a late‐phase reaction. Intrapapillary capillary loops were visualized with magnified narrow band imaging at the healing ulcer site as seen via the esophagus and, moreover, demonstrated histologically. 相似文献
54.
Naoyuki Iizuka Akiko Suzuki Kayoko Nozawa-Inoue Yoshiro Kawano B. G. T. L. Nandasena Takashi Okiji Takeyasu Maeda 《Journal of anatomy》2009,214(2):267-274
Caveolae are involved in clathrin-independent endocytosis, transcytosis, signal transduction, and tumor suppression – all of which depend on their main constituent protein caveolin families. The periodontal Ruffini ending has been reported to develop a caveola-like structure on the cell membrane of both the axon terminals and Schwann sheaths, suggesting the existence of an axon–Schwann cell interaction in the periodontal Ruffini endings. However, little information is available concerning the functional significance of these caveolae. The present study was undertaken to examine the immunolocalization of caveolin-1, -3 (Cav-1, Cav-3) and Ca2+ -ATPase in the periodontal Ruffini endings of the rat incisor. Decalcified sections of the upper jaws were processed for immunocytochemistry at the levels of light and electron microscopy. Some immunostained sections were treated with histochemistry for nonspecific cholinesterase (nChE) activity. Observations showed the periodontal Ruffini endings were immunopositive for Cav-1, but not Cav-3. Immunoreactive products for Cav-1 were confined to caveola-like structures in the cell membranes of the cytoplasmic extensions and cell bodies of the terminal Schwann cells associated with the periodontal Ruffini endings. However, the axonal membranes of the terminals did not express any Cav-1 immunoreaction. Double staining with Ca2+ -ATPase and either protein gene product 9.5 (PGP 9.5) or S-100 protein disclosed the co-localization of immunoreactions in the axonal branches of the periodontal Ruffini endings, but not in the terminal Schwann cells. As Ca2+ plays an important role in mechanotransduction, these characteristic immunolocalizations show Cav-1/Ca2+ -ATPase might be involved in the quick elimination of intracellular Ca2+ in mechanotransduction. 相似文献
55.
Yoshiyuki Kurata Machiko Oshida Hironori Take Takayasu Furubayashi Hirohisa Nakao Yoshiaki Tomiyama Yoshio Kanayama Nobuo Nagao Yasuto Okubo Takeshi Yonezawa and Seiichiro Tarui 《Vox sanguinis》1989,57(3):199-204
A new method was studied for eliminating HLA class I antigens from the surface of platelets without damaging the cells. Platelets were exposed to an acid solution (pH 3.0) to eliminate the antigenicity of HLA class I antigens. The reduction in antigenicities of HLA class I common antigen and individual HLA class I antigens by acid treatment was marked. Patients' sera which contained multispecific HLA antibodies reacted with PBS-treated platelets, but not with acid-treated platelets. No changes were observed in the antigenicities of glycoprotein Ib or glycoprotein IIb/IIIa. The viability of acid-treated platelets was 83%. Ultrastructural investigations revealed no significant difference between the PBS-treated platelets and acid-treated platelets. The platelet function studies showed that the aggregation of acid-treated platelets induced by various agonists was only slightly reduced compared with PBS-treated platelets. We propose that acid-treated platelets are promising for clinical use in patients refractory to platelet transfusions and may be superior to chloroquine-treated platelets for analysis of the specificity of antiplatelet antibodies. 相似文献
56.
Feng Xue Terumi Takahara Yutaka Yata Qiang Xia Kazunobu Nonome Eiji Shinno Masami Kanayama Shiro Takahara Toshiro Sugiyama 《Hepatology research》2008,38(8):810-817
Aim: There is growing evidence that the Rho/Rho-associated coiled coil-forming kinase (ROCK) signaling pathway is upregulated in tumors and plays a key role in cancer invasion and metastasis. Our aim was to test the anticancer effects of Rho/ROCK inhibitor, Y-27632, including possible mechanisms in a highly-metastasizing hepatocellular carcinoma (HCC) mouse model on its secretion of matrix metalloproteinase (MMP) and tumor progression.
Methods: Following orthotopic implantation of CBO140C12 HCC tumor fragments into the liver of mice, the mice were randomly assigned to a Y-27632-treated group or control group. After treatment for 4 weeks, specimens were obtained to evaluate tumor size, metastases, and immunohistochemical findings. In vitro , we examined the effects of Y-27632 and RhoC siRNA on MMP-2 and -9 expressions, invasiveness, and apoptosis in cultured tumor cells.
Results: Both RhoA and RhoC were upregulated in HCC-bearing livers, and Y-27632 significantly inhibited not only tumor growth and intrahepatic metastasis ( P < 0.05), but also tumoral MMP-9 expression. Moreover, Y-27632 treatment resulted in large necrotic areas in tumors. In vitro , Y-27632 and RhoC siRNA reduced MMP-2 and -9 expressions, as well as the chemotactic migration of tumor cells dose-dependently, and increased apoptosis eight times.
Conclusion: Y-27632 suppresses progression and limits the intrahepatic metastasis of established HCC. This could be linked to the decreased MMP expression and induction of apoptosis in tumor cells. Rho signaling may prove to be a productive target in anticancer therapy. 相似文献
Methods: Following orthotopic implantation of CBO140C12 HCC tumor fragments into the liver of mice, the mice were randomly assigned to a Y-27632-treated group or control group. After treatment for 4 weeks, specimens were obtained to evaluate tumor size, metastases, and immunohistochemical findings. In vitro , we examined the effects of Y-27632 and RhoC siRNA on MMP-2 and -9 expressions, invasiveness, and apoptosis in cultured tumor cells.
Results: Both RhoA and RhoC were upregulated in HCC-bearing livers, and Y-27632 significantly inhibited not only tumor growth and intrahepatic metastasis ( P < 0.05), but also tumoral MMP-9 expression. Moreover, Y-27632 treatment resulted in large necrotic areas in tumors. In vitro , Y-27632 and RhoC siRNA reduced MMP-2 and -9 expressions, as well as the chemotactic migration of tumor cells dose-dependently, and increased apoptosis eight times.
Conclusion: Y-27632 suppresses progression and limits the intrahepatic metastasis of established HCC. This could be linked to the decreased MMP expression and induction of apoptosis in tumor cells. Rho signaling may prove to be a productive target in anticancer therapy. 相似文献
57.
Masato Maeda MD Dr Masaaki Kanayama MD Yasushi Hasumura MD Jugoro Takeuchi MD Toshikazu Uchida MD 《Digestive diseases and sciences》1988,33(11):1487-1490
Summary A 56-year-old female with mixed connective tissue disease (MCTD) who developed autoimmune hepatitis is described. Hepatitis was controlled effectively by the corticosteroid therapy. Biopsy of the liver revealed swelling and hydropic degeneration of hepatocytes, accompanied by Councilman's body formation and focal necrosis. These histological findings differ from those in three previously described cases. A relationship between MCTD and liver involvement appears possible. 相似文献
58.
59.
Miyashita N Fukano H Hara H Yoshida K Niki Y Matsushima T 《Internal medicine (Tokyo, Japan)》2002,41(1):30-33
Two cases of recurrent pneumonia due to Chlamydia pneumoniae are described. C. pneumoniae was continuously detected from the nasopharynx in both patients by the polymerase chain reaction and/or culture even with appropriate antibiotic therapy during the first episode. After eradication of C. pneumoniae with long-term macrolide therapy, the respiratory symptoms of both patients completely disappeared and no relapse was observed. These data indicate that new treatment strategies may be necessary to eradicate the organism in patients prone to persistent infection. 相似文献
60.
Expression of GPIV and Naka antigen on monocytes in Naka -negative subjects whose platelets lack GPIV
Hironori Take Hirokazu Kashiwagi Yoshiaki Tomiyama Shigenori Honda Yumiko Honda Hajime Mizutani Takayasu Furubayashi Takahiro Karasuno Tetsuo Nishiura Yoshio Kanayama Yoshiyuki Kurata Yuji Matsuzawa 《British journal of haematology》1993,84(3):387-391
Summary. The platelet antigen Naka was once considered to be a platelet-specific alloantigen and is carried on platelet membrane glycoprotein (GP) IV. Recent studies suggest that Naka -negative subjects lack platelet GPIV. GPIV is an important adhesive receptor and expressed on the surface of monocytes as well as of platelets. In the present study, flow cytometry was used to detect GPIV and Naka antigen on the surface of monocytes. Naka antigen was expressed on monocytes as well as on platelets in Naka -positive subjects ( n = 6) (P-GPIV-positive subjects). To our surprise, monocytes of Naka -negative subjects ( n = 7) (P-GPIV-negative subjects) having no anti-Naka antibody in their serum expressed GPIV and Naka antigen to almost the same degree as did the monocytes of P-GPIV-positive subjects. Competitive experiments using OKM5 (a monoclonal antibody against GPIV) and anti-Naka antibody showed that the epitope of anti-Naka antibody on monocytes was very close to that of OKM5. In two P-GPIV-negative subjects having anti-Naka antibody in their serum, GPIV and Naka antigen were not expressed on the surface of either monocytes or platelets. These results indicate that the GPIV molecules and Naka antigen are expressed on the surface of monocytes in the majority of P-GPIV-negative subjects, but that in a very few P-GPIV-negative subjects neither GPIV nor Naka antigen is expressed on the surface of their monocytes. We hypothesize that P-GPIV-negative subjects who carry neither GPIV nor Naka antigen on their monocytes produce anti-Naka antibody as a result of transfusion or pregnancy. 相似文献