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排序方式: 共有1296条查询结果,搜索用时 15 毫秒
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Tomimori Y Muto T Fukami H Saito K Horikawa C Tsuruoka N Saito M Sugiura N Yamashiro K Sumida M Kakutani S Fukuda Y 《Laboratory investigation; a journal of technical methods and pathology》2002,82(6):789-794
An epicutaneous application of 2,4-dinitrofluorobenzene (DNFB) to a mouse ear caused a transient skin swelling, and the repetition of the challenge enlarged the contact dermatitis. The repeated challenge with DNFB also induced eosinophil infiltration on the application site. Administration of a chymase inhibitor significantly inhibited the ear swelling as well as eosinophil accumulation. An intradermal injection of human chymase to the mouse ear also elicited transient skin swelling and eosinophil infiltration, both of which were augmented in proportion to the number of injections. Human serum albumin and heat-inactivated chymase failed to induce such skin reactions, suggesting the participation of proteolytic activity of the enzyme. In addition, chymase stimulated eosinophil migration in vitro in a concentration-dependent manner. Taken together, these observations suggest that mast cell chymase may contribute to development of the DNFB-induced dermatitis, probably by promoting eosinophil infiltration. It is therefore possible that chymase plays a role in pathogenesis of chronic dermatitis such as atopic dermatitis. 相似文献
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Masamitsu Shirai Tatsuki Nagatsuka Makoto Tanaka 《Macromolecular chemistry and physics.》1978,179(1):173-179
The effect of polyanions on the formation of mixed dimers of methylene blue ( 1 ) and trypaflavine ( 2 ), methylene blue ( 1 ) and phenosafranine ( 3 ), and methylene blue ( 1 ) and pyronine G ( 4 ) was investigated spectrophotometrically. The following polyanions were used: poly(potassium styrenesulfonate) (PSS), poly(potassium vinyl sulfate) (PVS), and poly(sodium acrylate) (PAA). On addition of polyanions, the formation of mixed dimers was enhanced largely. Thermodynamic parameters inferred that the enhancement of the formation of mixed dimers in the presence of polyanions resulted from an entropic factor. 相似文献
5.
Masamitsu Shirai Tatsuki Nagatsuka Makoto Tanaka 《Macromolecular chemistry and physics.》1977,178(1):37-46
The structural effect of polyanions on the binding type of methylene blue ( 1 ) was investigated spectrophotometrically. 1 was bound to poly(potassium styrenesulfonate) (PSS) and poly(sodium 4-vinylphenylsulfate) (SVS) in the dimeric or slightly aggregated form and to poly(sodium vinylsulfonate) (SVF) and poly(potassium vinyl sulfate) (PVS) in the highly aggregated (polymeric) form. It was found that the flexibility of polyanions plays an important rǒle in the aggregation of bound 1 and that the difference between ? SO and ? OSO as binding site is not a significant factor. 相似文献
6.
Abeta-degrading endopeptidase,neprilysin, in mouse brain: synaptic and axonal localization inversely correlating with Abeta pathology 总被引:5,自引:0,他引:5
Fukami S Watanabe K Iwata N Haraoka J Lu B Gerard NP Gerard C Fraser P Westaway D St George-Hyslop P Saido TC 《Neuroscience research》2002,43(1):39-56
Metabolism of amyloid-beta peptide (Abeta) is closely associated with the pathology and etiology of Alzheimer's disease (AD). Since neprilysin is the only rate-limiting catabolic peptidase proven by reverse genetics to participate in Abeta metabolism in vivo, we performed detailed immunohistochemical analysis of neprilysin in mouse brain using neprilysin-deficient mice as a negative control. The aim was to assess, at both the cellular and subcellular levels, where Abeta undergoes neprilysin-dependent degradation in the brain and how neprilysin localization relates to Abeta pathology in amyloid precursor protein (APP)-transgenic mice. In hippocampus, neprilysin was present in the stratum pyramidale and stratum lacunosum-moleculare of the CA1-3 fields and the molecular layer of the dentate gyrus. Confocal double immunofluorescence analyses revealed the subcellular localization of neprilysin along axons and at synapses. This observation suggests that after synthesis in the soma, neprilysin, a type II membrane-associated protein, is axonally transported to the terminals, where Abeta degradation is likely to take place. Among various cell types, GABAergic and metabotropic glutamate 2/3 receptor-positive neurons but not catecholaminergic or cholinergic neurons, expressed neprilysin in hippocampus and neocortex, implying the presence of a cell type-specific mechanism that regulates neprilysin gene expression. As expected, Abeta deposition correlated inversely with neprilysin expression in TgCRND8 APP-transgenic mice. These observations not only support the notion that neprilysin functions as a major Abeta-degrading enzyme in the brain but also suggest that down-regulation of neprilysin activity, which may be caused by aging, is likely to elevate local concentrations of Abeta at and around neuronal synapses. 相似文献
7.
Cellular niches controlling B lymphocyte behavior within bone marrow during development 总被引:19,自引:0,他引:19
In bone marrow, hematopoiesis is thought to depend on special microenvironments known as niches that maintain blood cells. However, the identity of niches and interaction of blood cells with niches remain poorly understood. Here we identify stage-specific cellular niches for B lymphopoiesis. The earliest precursors, pre-pro-B cells and end-stage B cells, plasma cells require CXC chemokine ligand (CXCL)12. CXCL12-expressing cells are a small population of stromal cells, scattered throughout bone marrow and located some distance from the cells expressing interleukin (IL)-7. Multipotent hematopoietic progenitors are attached to the processes of CXCL12-expressing cells and pre-pro-B cells adjoin their cell bodies. Maturer pro-B cells that require IL-7 have moved away and adjoin the IL-7-expressing cells. Plasma cells again seed CXCL12-expressing cells. We demonstrate the B lymphocyte characteristic location and movement between specific niches within bone marrow during development and suggest that CXCL12 maintains the cells in the niche. 相似文献
8.
Koichi Hatada Tatsuki Kitayama Keith Saunders Robert W. Lenz 《Macromolecular chemistry and physics.》1981,182(5):1449-1458
The 13C NMR spectra measured at 25 MHz of the methyl and propyl esters of isotactic and syndiotactic poly(α-bromoacrylate) were sufficiently resolved to be analysed for pentad tacticity sequences. The pentad tacticity of the syndiotactic polymers prepared with free radical initiators at ?40°C agreed with those calculated for Bernoullian sequence distributions based on Pr values of 0,83–0,87. The tacticities of the isotactic polymers prepared with heterogeneous catalysts were determined on the basis of these assignments. Good internal consistency was obtained between the calculated and observed pentad proportions from the quaternary and carbonyl carbon peaks in the spectra of these polymers. The order of chemical shifts for the meso and racemic dyads and tetrads in these polymers were opposite to those found in the equivalent methacrylate polymers, but as with the latter, the 13C-T1 values were longer in the isotactic than in the syndiotactic polymers. 相似文献
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Yoshida M Abe O Uchino J Kikuchi K Abe R Enomoto K Tominaga T Fukami A Sakai K Koyama H Sugimachi K Nomura Y Hattori T Ogawa N 《Breast cancer (Tokyo, Japan)》1997,4(2):103-113
A multi-center, randomized controlled collaborative study was conducted in 310 institutions located throughout Japan for 3 years and 9 months from February 1985 until October 1988 to evaluate the efficacy of post-operative adjuvant therapy for patients who had previously undergone curative surgery for treatment of Stage IIIa breast cancer. Patients with estrogen receptor-positive [ER( + )] breast cancer were treated with two types of regimens, ie, cyclophosphamide + adriamycin + fluorouracil (CAF; 2 cycles) + Futraful (FT) or CAF (2 cycles) + FT + tamoxifen (TAM), and the clinical benefit of additional use of TAM was evaluated. Of the 509 ER( + ) patients registered for the trial, 473 patients (92.9%) were eligible for evaluation. The 5-year survival rate was 77.2% for the CAF + FT group and 74.6% for the CAF + FT+TAM group, and the 5-year disease-free survival rate was 56.7% for the CAF+FT group and 59.2% for the CAF + FT + TAM group. Neither the survival rate nor the disease-free survival rate differed significantly between the groups. Analyses by factor revealed that the 5-year disease-free rate for lymph node-negative patients in the CAF + FT + TAM group was significantly higher than that for the corresponding patients in the CAF + FT group. No differences were noted in the incidence of adverse reactions between the two treatment groups, other than an increase in LDH (the frequency of which was higher in the CAF + FT+TAM group than in the CAF + FT group). Patients with estrogen receptor-negative [ER( -)] breast cancer were treated with two types of regimens, ie, CAF + FT or CAF + FT + adriamycin (ADR), and the clinical benefit of the combined use of intermittent doses of ADR was evaluated. Of the 514 ER(-) patients registered in the trial, 478 (93.0%) were eligible for evaluation. The 5-year survival rate was 64.9% for the CAF + FT group and 63.0% for the CAF + FT + ADR group, and the 5-year disease-free survival rate was 59.2% for both CAF + FT and CAF + FT + ADR groups. Neither the survival rate nor the disease-free survival rate differed significantly between the groups. There were no significant differences between these groups in analyses by nodal or menopausal status. The incidences of adverse reactions including anorexia, nausea/vomiting and alopecia were higher in the CAF + FT+ADR group than in the CAF + FT group. 相似文献