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Terao K Nagasawa N Nishida H Furusawa K Mori Y Yoshii F Dobashi T 《Journal of biomaterials science. Polymer edition》2003,14(11):1197-1208
In order to obtain a gelatin hydrogel crosslinked by a reagent-free method, gamma-ray and electron beam radiation was applied to porcine, bovine and fish gelatin gels and the products were characterized by measuring the gel fraction, the swelling ratio and the enzymatic degradability. On increasing the radiation dose, the gel fraction increased and both the swelling ratio and the enzymatic degradability decreased. The transition temperature from gel to sol of the hydrogel containing more than 5% mammal gelatins increased up to more than 90 degrees C when gamma-ray or electron beam were irradiated by more than 10 kGy. The results show that the degree of crosslinking of irradiated gelatin hydrogels increases with increasing irradiation dose and with decreasing concentration. It is suggested that the radiation crosslinking occurs around the physical crosslinking point or multiple helix structure of gelatin gel. 相似文献
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Sudo N Aiba Y Oyama N Yu XN Matsunaga M Koga Y Kubo C 《International archives of allergy and immunology》2004,135(2):132-135
BACKGROUND: Intestinal microbiota are known to play an important role in the establishment of oral tolerance, thereby protecting the organism from food allergies. Dietary intake of nucleic acid (NA) is also reported to have such an anti-allergic effect; however, one unsolved question is whether or not dietary NA would act through a process of toll-like receptor 9 signaling activated by DNA containing a CpG motif, a well-known sequence leading to immunostimulatory activity. In this study, we focused on the question of whether the addition of dietary NA lacking CpG motifs would allow continued modulation of the Th1/Th2 balance. METHODS: Germ free (GF) and Bifidobacterium-infantis-monoassociated BALB/c mice were maintained on either an NA-free casein diet or on an NA-supplemented casein diet for 4 weeks. Thereafter, both the in vivo anti-casein antibody levels and in vitro splenocyte cytokine secretion pattern were evaluated. RESULTS: Feeding with a casein diet elicited a substantial increase in the serum anti-casein-specific IgG1, IgG2a, and IgE levels of GF mice fed the NA free-diet. The in vitro cytokine production profile showed that enhanced IL-4 production in the GF mice fed the NA free-diet was markedly reduced by the supplementation with dietary NA in both the GF and B.-infantis-monoassociated mice. In addition, IFN-gamma secretion increased in the B.-infantis-reconstituted mice fed the diet containing NA. CONCLUSIONS: These results suggest that dietary intake of NA devoid of CpG motifs may prevent the development of allergies via acceleration of Th1-dominant immunity. 相似文献
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S Nakamura N Takagi K Kitoh T Koshikawa K Hayashi K Yamamoto H Suzuki A Oyama R Ueda T Suchi 《Acta pathologica japonica》1992,42(2):141-149
A case of angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) which showed widespread involvement of the gastrointestinal tract is reported. A lymph node biopsy specimen showed the characteristic histological features of AILD. During the progression of the illness, lymphomatous lesions developed in the gastrointestinal tract, complicated by cytomegalovirus infection. A double immunoenzymatic study using a combination of Ki-67 antibody and antibodies against surface antigens demonstrated that CD3+, CD4+, and/or T-cell receptor (TCR) beta+ cells were predominant (67-68%) among the population of proliferating Ki-67% cells, rather than CD8+ or CD22+ cells. Clonal rearrangement of the TCR beta chain gene was also detected. These findings provide further evidence for the neoplastic nature of lesions of this type, and the diagnosis of peripheral T-cell lymphoma. 相似文献
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In order to confirm the role of 14-3-3 sigma (sigma) as a tumor suppressor in breast carcinogenesis, we have studied the expression of 14-3-3sigma immunohistochemically in usual ductal hyperplasia (UDH), ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) breast lesions. Immunostaining for estrogen receptor alpha (ERalpha), p53 and estrogen-responsive RING finger protein (Efp) was also carried out. Immunohistochemically, expression of 14-3-3sigma was seen in 92% UDH lesions and gradually decreased from 65% in DCIS to 23% in IDC. The expression of ERalpha decreased gradually from UDH to DCIS to IDC, while p53 showed an inverse staining pattern to that of ERalpha. The expression of Efp showed no significant difference among the three breast lesions. Hence, the present immunohistochemical study confirmed 14-3-3sigma as a tumor suppressor in breast carcinogenesis. A similar immunohistochemical analysis was then carried out on columnar cell hyperplasia with atypia (CCHA), in which the expression pattern of tumor suppressor 14-3-3sigma, ERalpha and p53 suggested that it might be possible that CCHA is a precancerous lesion. 相似文献
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Face recognition in preschool children: effects of familiarity, facial expression and angle of view]
M Oyama 《Shinrigaku kenkyu : The Japanese journal of psychology》1992,63(4):248-255
The purpose of this study was to investigate the face recognition processes in preschool children. Two experiments were carried out to examine the effects, on face recognition, of familiarity, facial expression and angle of view of faces as well as changes or no changes in facial expression and/or angle of view occurring between the first presentation and the subsequent recognition test. The subjects were 188 five- and six-year old children. In Experiments 1 and 2, half of the faces were highly familiar to the subjects, and the remaining half unfamiliar to them. In Experiment 1, the facial expressions (e.g., smiling or serious) were either changed or unchanged. In Experiment 2, the facial expressions or angles of view (e.g., full-face views or three-quarter views of faces) were either changed or unchanged. The major findings were that the familiar faces and the smiling faces were recognized more correctly than the unfamiliar faces and the serious faces respectively. The results were discussed in terms of 'identity-specific semantic codes' and 'visually-derived semantic codes'. 相似文献
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