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排序方式: 共有5065条查询结果,搜索用时 343 毫秒
71.
Toshiyuki Tanaka Yasuhiko Nagasaka Fujiko Kitamura Keisuke Kuida Hiroshi Suwa Masayuki Miyasaka 《European journal of immunology》1993,23(6):1378-1380
Autoimmune MRL/MP-lpr/lpr (MRL/lpr) mice spontaneously develop a systemic lupus erythematosus-like disease accompanied by a profound lymphadenopathy that consists of CD4?8?B220+ a P T cells. By the use of cross-linking experiments with radiolabeled interleukin-2 (IL-2), these abnormal T cells have been reported to constitutively express the IL-2 receptor β chain (IL-2Rα), a signal transducing component of IL-2R, in the absence of the a chain (IL-2Rα).To critically reevaluate the role of the IL-2/IL-2R pathway in the pathogenesis of lymphadenophathy we examined expression of the IL-2Rα and IL-2Rβ in MRL/lpr mice by 125I-IL-2 binding analysis and also by flow cytometric analysis using monoclonal antibodies against each component of the receptor. We found that, contrary to the previous report, the CD4?8?B220+ α β T cells in lymph node (LN) of MRL/lpr mice were negative for both IL-2Rα and IL-2Rβ expression. The lpr liver CD4?8?B220+ a P T cells that had been implicated in the genesis of these abnormal LN T cells were also negative for IL-2Rβ expression. Therefore, our results indicate that the IL-2/IL-2R system plays little role, if any, in the expansion of abnormal CD4?8? B220+ α β T cells in MRL/lpr mice. 相似文献
72.
Polyethylene/phospholipid polymer alloy as an alternative to poly(vinylchloride)-based materials 总被引:1,自引:0,他引:1
To develop new biomaterials for making medical devices, polymer alloys composed of a phospholipid polymer, poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC), and polyethylene (PE) were prepared. The PE/PMPC alloy membrane could be obtained by a combination of solution mixing and solvent evaporation methods using xylene and n-butanol mixture as a solvent. Moreover, thermal treatment was applied to improve the mechanical properties of the PE/PMPC alloy membrane. In the PE/PMPC alloy membrane, the PMPC domains were located not only inside the membrane but also at the surface. Surface analysis of the PE/PMPC alloy membrane with X-ray photoelectron spectroscopy, wettability evaluation, and dynamic contact angle measurements revealed that the phospholipid polar groups in the PMPC covered the surface even after thermal treatment. Blood compatibility tests with attention to platelet adhesion and change in morphology of adhered platelets showed that the PE/PMPC alloy membrane had excellent platelet adhesion resistance. We finally concluded that the PE/PMPC alloy could be used as biomaterials instead of poly(vinyl chloride)-based materials. 相似文献
73.
Secretory role for human uterodomes (pinopods): secretion of LIF 总被引:5,自引:0,他引:5
Kabir-Salmani M Nikzad H Shiokawa S Akimoto Y Iwashita M 《Molecular human reproduction》2005,11(8):553-559
The differentiation of human endometrial epithelium is a dynamic event, which occurs throughout the menstrual cycle in preparation for pregnancy. The appearance of uterodomes (pinopods) in this regard was first introduced in rodents with an established pinocytotic function, whereas little evidence was available in humans in this context. This study was undertaken to identify the potential physiological roles of uterodomes in the implantation process. To address this, endometrial biopsies from early, mid- and late luteal phases of the menstrual cycle of 23 fertile female patients with regular menses were used. Scanning and transmission electron microscopies (SEM and TEM) as well as immunofluorescence and immunogold TEM were performed to study the morphological changes and the expression pattern of leukaemia inhibitory factor (LIF) at uterodomes. Our results illustrated a high level of LIF expression in the human uterodomes, which was colocalized with the well-known biochemical markers of exocytosis, including syntaxin-1, 25-kDa synaptosomal protein (SNAP-25) and vesicle-associated membrane protein-2 (VAMP-2). Our morphological and immunocytochemical findings illustrated a secretory function for human uterodomes for the first time. In conclusion, this novel function for uterodomes provides an important clue in detection of their physiological function(s) during the process of the plasma membrane transformation. 相似文献
74.
Association between HLA and Japanese patients with rheumatoid arthritis 总被引:12,自引:0,他引:12
N Ohta Y K Nishimura K Tanimoto Y Horiuchi C Abe Y Shiokawa T Abe M Katagiri T Yoshiki T Sasazuki 《Human immunology》1982,5(2):123-132
Japanese patients with rheumatoid arthritis (RA) were observed to have a statistical association with HLA-DR4, MT3. Strong association between the clinical severity of RA and HLA was also observed. Male patients had a stronger association with HLA than female patients. Males are more resistant to RA than females. This suggested that the threshold of liability for RA is higher in males than in females. Japanese patients with RA with systemic vasculitis were negative for HLA-Bw44 and had antilymphocytotoxic autoantibody, indicating that RA with systemic vasculitis is different in etiology from RA without systemic vasculitis. 相似文献
75.
Tissue regeneration using macrophage migration inhibitory factor-impregnated gelatin microbeads in cutaneous wounds 下载免费PDF全文
Zhao Y Shimizu T Nishihira J Koyama Y Kushibiki T Honda A Watanabe H Abe R Tabata Y Shimizu H 《The American journal of pathology》2005,167(6):1519-1529
Migration inhibitory factor (MIF) responds to tissue damage and regulates inflammatory and immunological processes. To elucidate the function of MIF in cutaneous wound healing, we analyzed MIF knockout (KO) mice. After the excision of wounds from the dorsal skin of MIF KO and wild-type (WT) mice, healing was significantly delayed in MIF KO mice compared to WT mice. Lipopolysaccharide treatment significantly increased [(3)H]thymidine uptake in WT mouse fibroblasts compared to MIF KO mouse fibroblasts. Furthermore, there was a significant reduction in fibroblast and keratinocyte migration observed in MIF KO mice after 1-oleoyl-2-lysophosphatidic acid treatment. We subsequently examined whether MIF-impregnated gelatin slow-release microbeads could accelerate skin wound healing. Injection of more than 1.5 microg/500 microl of MIF-impregnated gelatin microbeads around a wound edge accelerated wound healing compared to a single MIF injection without the use of microbeads. MIF-impregnated gelatin microbeads also accelerated skin wound healing in C57BL/6 mice and diabetic db/db mice. Furthermore, incorporating MIF-impregnated gelatin microbeads into an artificial dermis implanted into MIF KO mice accelerated procollagen production and capillary formation. These findings suggest that MIF is crucial in accelerating cutaneous wound healing and that MIF-impregnated gelatin microbeads represent a promising treatment to facilitate skin wound healing. 相似文献
76.
77.
Recombinant Sendai viruses with L1618V mutation in their L polymerase protein establish persistent infection, but not temperature sensitivity 总被引:2,自引:0,他引:2
The Sendai virus pi strain (SeVpi) isolated from cells persistently infected with SeV shows mainly two phenotypes: (1) temperature sensitivity and (2) an ability of establishing persistent infection (steady state). Three amino acid substitutions are found in the Lpi protein and are located at aa 1088, 1618, and 1664. Recombinant SeV(Lpi) (rSeV(Lpi)) having all these substitutions is temperature sensitive and is capable of establishing persistent infection (steady state). rSeVs carrying the fragment containing L1618V show both phenotypes. rSeV(L1618V), in which leucine at aa 1618 is replaced with valine, has the ability of establishing persistent infection, but is not a temperature-sensitive mutant, indicating that the ability of a virus to establish persistent infection can be separated from temperature sensitivity. The amino acid change at 1618(L-->V) coexisting with aa 1169 threonine is required for acquirement of a temperature-sensitive phenotype. Three amino acid substitutions are also found in the Ppi protein, but rSeV(Ppi) does not show these phenotypes. 相似文献
78.
79.
Tomomi Yamaguchi Shujiro Hayashi Daisuke Hayashi Takeshi Matsuyama Norimichi Koitabashi Kenichi Ogiwara Masaaki Noda Chiai Nakada Shinya Fujiki Akira Furutachi Yasuhiko Tanabe Michiko Yamanaka Aki Ishikawa Miyako Mizukami Asako Mizuguchi Kazumitsu Sugiura Makoto Sumi Hirokuni Yamazawa Atsushi Izawa Yuko Wada Tomomi Fujikawa Yuri Takiguchi Keiko Wakui Kyoko Takano Shin-Ya Nishio Tomoki Kosho 《American journal of medical genetics. Part A》2023,191(1):37-51
Vascular Ehlers–Danlos syndrome (vEDS) is a hereditary connective tissue disorder (HCTD) characterized by arterial dissection/aneurysm/rupture, sigmoid colon rupture, or uterine rupture. Diagnosis is confirmed by detecting heterozygous variants in COL3A1. This is the largest Asian case series and the first to apply an amplification-based next-generation sequencing through custom panels of causative genes for HCTDs, including a specific method of evaluating copy number variations. Among 429 patients with suspected HCTDs analyzed, 101 were suspected to have vEDS, and 33 of them (32.4%) were found to have COL3A1 variants. Two patients with a clinical diagnosis of Loeys–Dietz syndrome and/or familial thoracic aortic aneurysm and dissection were also found to have COL3A1 variants. Twenty cases (57.1%) had missense variants leading to glycine (Gly) substitutions in the triple helical domain, one (2.9%) had a missense variant leading to non-Gly substitution in this domain, eight (22.9%) had splice site alterations, three (8.6%) had nonsense variants, two (5.7%) had in-frame deletions, and one (2.9%) had a multi-exon deletion, including two deceased patients analyzed with formalin-fixed and paraffin-embedded samples. This is a clinically useful system to detect a wide spectrum of variants from various types of samples. 相似文献
80.
Tsukamoto F Shiba E Taguchi T Sugimoto T Watanabe T Kim SJ Tanji Y Kimoto Y Izukura M Takai SI 《Breast cancer (Tokyo, Japan)》1997,4(4):259-263
Overexpression of P-glycoprotein (Pgp) in tumors is one of the major mechanisms which mediates the multidrug resistance (MDR)
phenotype. To evaluate the prognostic significance of Pgp in breast cancer, Pgp expression was examined in paraffin-embedded
tissue sections of 94 breast cancer specimens by immunohistochemistry. Tissue specimens were obtained by mastectomy without
preoperative chemotherapy. UIC2 monoclonal antibody which recognizes an extracellular epitope of human Pgp was employed. Of
the 94 breast cancer specimens, 35 (37.2%) were positive for Pgp expression. Pgp expression had no correlation with menopausal
or hormone receptor status, axillary lymph node involvement or tumor size. However, a significant correlation was observed
between Pgp expression and disease relapse (p = 0.0322). Pgp-positive patients showed a significantly shorter disease-free survival period than Pgp-negative patients by
the Kaplan-Meier method (p = 0.0433). These results suggest that immunohistochemical detection of Pgp in breast cancer tissue may have prognostic value
after radical operation. 相似文献