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101.
Harimaya A Tarkkanen J Mattila P Fujii N Ylikoski J Himi T 《Clinical and diagnostic laboratory immunology》2005,12(9):1130-1134
We evaluated the immunological potential of adenoidal lymphocytes from children with recurrent otitis media. Interleukin-4 release and CD69 expression were lower in adenoidal lymphocytes than in peripheral blood lymphocytes (PBL). Our results suggest that there may be a difference between the immunological potential of adenoidal lymphocytes and that of PBL in children with otitis. 相似文献
102.
S Hirayama H Kohrogi A Ueda C Kiyofuji N Hirata K Fujii E Goto K Fujita K Tsumori S Hirosako D Noguchi O Kawano M Ando 《Arerugī》2001,50(12):1163-1170
Several reports have suggested that the prevalence of asthma in adults is currently increasing. However, recent prevalence of asthma has not reported in Japan, especially in rural-mountain areas. To investigate the prevalence of asthma in adults in Japan, we conducted clinical epidemiological research on 5066 inhabitants of Menda town, in a rural-mountain area of Japan. The study population comprised 98.7% of adults in the town, including senior high school students whose age were more than 15 years old. The prevalence of asthma among adults was 3.6%. The ratio of prevalence in males to prevalence in females was 1.44. Peaks prevalences were observed in the age ranges of 15-19 and > 70 years old in males, and 15-19, 40-49 and > 70 years old in females. 相似文献
103.
Zou Jian-Ping; Yamamoto Norihiko; Fujii Tetsuya; Takenaka Hiroshi; Kobayashi Michiko; Herrmann Steven H.; Wolf Stanley F.; Fujiwara Hiromi; Hamaoka Toshiyuki 《International immunology》1995,7(7):1135-1145
Unfractionated spleen cells taken from tumor-bearing mice 2weeks after tumor implantation contained tumor-primed T cellswhich produced cytokines including IL-2 and IFN- when culturedin vitro. With progressive tumor growth this initial lymphokine-producingcapacity decreased. Here, we investigated the ability of IL-12to (I) restore suppressed IFN- production, (II) cause tumorregression and (II) induce anti-tumor protective immunity. Additionof rIL-12 to spleen cell cultures from 4- to 10-week-old tumor-bearingmice resulted in a striking enhancement in the production ofIFN- compared with cultures of these cells in the absence ofrIL-12 or of normal spleen cells in the presence of rIL-12.Five I.p. injections of rIL-12 into mice bearing s.c. tumorsinduced complete tumor regression. This was found when rIL-12was given at early (1–2 weeks), intermediate (4–5weeks) or even late (7 weeks) stages of tumor growth. Furthermore,IL-12-treated mice which rejected the primary tumor exhibitedcomplete resistance to a rechallenge with the same tumor butdid not reject a second syngenetic tumor. Immunohistochemicalanalyses following IL-12 treatment revealed that CD4+ and CD8+T cells infiltrate the tumor. More importantly, IFN- mRNA expressionwas observed in fresh tumor masses from tumor-bearing mice receivingIL-12 treatment The importance of IFN- was further demonstratedby the observation that the systemic administration of anti-IFN-mAb prior to IL-12 treatment completely abrogated the anti-tumoreffect of IL-12. Thus, these results indicate that administrationof modest levels of rIL-12 to tumor-bearing mice results intumor regression through mechanisms involving reversal of suppressedIFN- production by anti-tumor T cells and the establishmentof a tumor-specific protective immune response. 相似文献
104.
The expression of human leukocyte antigen-G on trophoblasts abolishes the growth-suppressing effect of interleukin-2 towards them 总被引:9,自引:0,他引:9
Hamai Y Fujii T Yamashita T Miki A Hyodo H Kozuma S Geraghty DE Taketani Y 《American journal of reproductive immunology (New York, N.Y. : 1989)》1999,41(2):153-158
PROBLEM: We have shown the attenuated human leukocyte antigen (HLA)-G expression on trophoblasts and an aberrant expression of interleukin (IL)-2, a cytotoxic cytokine, in decidual tissue in preeclampsia, where deteriorated trophoblastic invasion into decidual layers may constitute a crucial pathogenesis. We hypothesized that the absence of HLA-G might make trophoblasts susceptible to compromise by IL-2. METHOD OF STUDY: We analyzed the growth of HLA-G-negative and positive cell lines, all of which possessed IL-2 receptors, in the culture with or without IL-2 supplementation. RESULTS: The proliferation of HLA-G positive trophoblastic cell lines (BeWo and JEG-3) was not influenced by the addition of IL-2, whereas a HLA-G-negative trophoblastic cell line (JAR) exhibited significantly decreased proliferation when cultured with IL-2. Interestingly, the transfection of JAR cells with HLA-G completely eliminates the growth-inhibitory effect of IL-2. CONCLUSION: The expression of HLA-G may commit trophoblasts to evade cell damage by IL-2, which may be relevant to maternal tolerance of the fetus during pregnancy and its derangement as exemplified by preeclampsia. 相似文献
105.
106.
The induction of intestinal metaplasia in rats by pyloroplasty or pyloroplasty plus vagotomy 总被引:1,自引:0,他引:1
The influence of increased gastric pH on induction of intestinal metaplasia in the stomach of male JCL/SD rats was examined following surgical procedures of pyloroplasty or pyloroplasty and vagotomy. Twelve months after pyloroplasty plus vagotomy serum gastric concentrations were significantly higher (group II) than in rats receiving only pyloroplasty (group I) or in sham operated animals (group III). Additionally, trehalase activity was also higher in group II than in groups I and III. The incidence of intestinal metaplasia was significantly higher in groups I and II compared with the sham operated control animals (group III). This study indicates that intestinal metaplasia could be induced by surgical procedures such as pyloroplasty with or without vagotomy. Furthermore, elevation of the pH on gastric mucosa by such procedures may play a significant role in the subsequent development of metaplasia in the stomach. 相似文献
107.
Tadakazu Shimoda Shokan Tanoue Masahiro Ikegami Yasuhiro Fujii Tetsuya Muroya Eisei Ishikawa 《Pathology international》1983,33(6):1259-1267
The present study includes a histopathological and immunohistochemical study of 4 cases of diffuse hyperplasia of gastric argyrophil cells. The mode of proliferation of these cells and the production of hormone by these cells have been documented. The distribution of microacinar nests composed of argyrophil cells was thought to be related to chronic gastritis in which there are atrophy of mucosa and intestinal metaplasia. In the case in which these nests were found only in the corpus ventriculi, there was intestinal metaplasia throughout the stomach. On the other hand, in the case in which these nests appeared only in the pyloric area, atrophy of the mucosa with mild intestinal metaplasia was observed only in the pyloric area. The microacinar nests composed of argyrophil cells were distributed in the deep mucosa at the basal portion of the glands in the area with intestinal metaplasia. Serial sections revealed a sprout composed of argyrophil cells budding from the gland with intestinal metaplastic changes. The sprout buds out from the growth zone of glands with Intestinal metaplasia and then becomes isolated and gives rise to reactive hyperplasia. The peptide hormone contained in these cells differs according to the mucosal environments. Cells containing gastrin were observed in the pyloric area, but not in the corpus ventriculi where there was marked intestinal metaplasia. The cells in this area were assumed to contain other hormones. 相似文献
108.
Fujii T Okuda J Tsukiura T Ohtake H Suzuki M Kawashima R Itoh M Fukuda H Yamadori A 《Neuroscience research》2002,44(4):429-438
The recent advent of neuroimaging techniques provides an opportunity to examine brain regions related to a specific memory process such as episodic memory encoding. There is, however, a possibility that areas active during an assumed episodic memory encoding task, compared with a control task, involve not only areas directly relevant to episodic memory encoding processes but also areas associated with other cognitive processes for on-line information. We used positron emission tomography (PET) to differentiate these two kinds of regions. Normal volunteers were engaged in deep (semantic) or shallow (phonological) processing of new or repeated words during PET. Results showed that deep processing, compared with shallow processing, resulted in significantly better recognition performance and that this effect was associated with activation of various brain areas. Further analyses revealed that there were regions directly relevant to episodic memory encoding in the anterior part of the parahippocampal gyrus, inferior frontal gyrus, supramarginal gyrus, anterior cingulate gyrus, and medial frontal lobe in the left hemisphere. Our results demonstrated that several regions, including the medial temporal lobe, play a role in episodic memory encoding. 相似文献
109.
Fujii S Kuroda Y Ito KL Yoshioka M Kaneko K Yamazaki Y Sasaki H Kato H 《Neuroscience letters》2000,279(2):121-124
A train of low-frequency afferent stimuli (LFS, 1 Hz, 1000 pulses), given 60 min prior to a tetanus (100 Hz, 100 pulses), suppresses the induction of long-term potentiation (LTP) in which a short-term potentiation decreases gradually back to the pre-tetanic level within 40-50 min (LTP suppression). We investigated the effects of adenosine A1 or A2 receptor antagonists (8-cyclopentyltheophylline (8-CPT) and CP-66713, respectively) on LTP suppression in CA1 neurons of guinea pig hippocampal slices. When the LFS was delivered in the presence of 8-CPT (1 microM), LTP suppression was not significantly affected. However, when LFS was delivered in the presence of CP-66713 (10 microM), LTP suppression was inhibited, leading to successful LTP induction. These results indicate that endogenous adenosine, acting via A2 receptors, is involved in the mechanism of LTP suppression. 相似文献
110.
BACKGROUND: Although some previous research has focused on the relationship between panic disorder (PD) and a high total cholesterol (TC) level, it is still controversial. Recently, researchers have reported the heterogeneity of clinical symptoms in PD and the complexity of the correlations found among them. Therefore, the controversy on the TC level in PD may be due to the existence of clinical subgroups in PD. It is important to ascertain whether or not an elevated TC level in patients with PD is associated with specific panic symptoms. METHODS: In 104 drug-free patients with PD, we examined the relationship between TC level and each of several panic symptoms occurring at the time of panic attacks (PAs), which included anticipatory anxiety, agoraphobia, and 13 panic symptoms based on the DSM-III-R. RESULTS: Stepwise regression analysis revealed a significant effect of the presence of the symptom 'fear of dying' on TC levels. Patients with a fear of dying had a significantly higher TC level than those without it. LIMITATIONS: The relatively small sample size may limit the generalizability of our findings. DISCUSSION: These data suggest that TC level may be associated with panic symptoms in patients with PD. 相似文献