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排序方式: 共有6618条查询结果,搜索用时 15 毫秒
51.
Tsutomu Imai MD Akiko Horiuchi MD Tanri Shiozawa MD Ryosuke Osada MD Norihiko Kikuchi MD Satoshi Ohira MD Kenji Oka MD Ikuo Konishi MD 《Human pathology》2004,35(12):2067
E-cadherin and catenins play key roles in cell adhesion and motility. Little is known about the changes in expression of these molecules in the progression of ovarian carcinomas. In the present study, the immunohistochemical expression of E-cadherin and α-, β-, and γ-catenins was examined in 77 cases of ovarian carcinoma. In addition, the expression of these molecules was evaluated in 26 matched pairs of primary and metastatic lesions of advanced ovarian carcinomas. Of the 77 primary lesions, positive staining for E-cadherin and α-, β-, and γ-catenin was observed in 75 (97%), 63 (82%), 71 (92%) and 57 (74%) cases, respectively. Positivity for E-cadherin and α-, β-, and γ-catenin was significantly decreased in stage III and IV tumors compared with stage I and II tumors, suggesting that expression of the cadherin-catenin complex is reduced with the advancing stages of a tumor. Interestingly, expression of E-cadherin and α-, β-, and γ-catenin in the lesions of peritoneal dissemination was significantly increased compared with the primary lesions. These findings suggest that expression of the cadherin-catenin complex changes markedly and that reexpression may occur during the peritoneal dissemination of ovarian carcinoma cells. 相似文献
52.
53.
Wang C Horiuchi A Imai T Ohira S Itoh K Nikaido T Katsuyama Y Konishi I 《The Journal of pathology》2004,202(2):215-223
BRCA1 is a putative tumour suppressor gene responsible for a hereditary ovarian cancer syndrome. To clarify the possible involvement of BRCA1 in the development of sporadic ovarian neoplasms, this study analysed the immunohistochemical expression of BRCA1 protein in normal ovarian surface epithelium and 119 epithelial ovarian tumours (19 benign, 24 borderline, and 76 malignant tumours). Loss of heterozygosity (LOH) of BRCA1 was examined using three microsatellite markers to analyse the relationship between BRCA1 expression and alterations of the BRCA1 gene. Methylation of the BRCA1 promoter was also analysed by methylation-specific PCR. In ovarian carcinomas showing heterogeneous expression of BRCA1 protein in the same tumour, LOH and methylation status were analysed using microdissection techniques. Finally, the relationship of BRCA1 expression or its genetic alteration to clinicopathological parameters and patient survival was analysed. Ovarian surface epithelial cells expressed BRCA1 protein. Decreased expression of BRCA1 was found in 16% of benign tumours, 38% of borderline tumours, and 72% of carcinomas. LOH of BRCA1 was demonstrated in no benign tumours, 15% of borderline tumours, and 66% of carcinomas. Methylation of BRCA1 was not detected in benign or borderline tumours, but was present in 31% of carcinomas. Reduced expression of BRCA1 correlated with the presence of gene methylation. The frequency of BRCA1 methylation and LOH was higher in serous carcinomas than in other types. In one of the three serous carcinomas that showed heterogeneous expression of BRCA1, BRCA1-positive borderline-like tumour cells were LOH-positive and methylation-negative, whereas adjacent BRCA1-negative carcinoma cells were LOH-positive and methylation-positive. The prognosis of carcinoma patients did not correlate with BRCA1 expression or genetic status. These findings suggest that reduced expression of BRCA1 protein along with genetic and epigenetic changes of the BRCA1 gene play an important role in the development of sporadic ovarian carcinomas, particularly those of serous histology. 相似文献
54.
Yoshio Mii Yoshizumi Miyauchi Kanya Hohnoki Hiroshi Maruyama Masahiro Tsutsumi Kayoko Dohmae Susumu Tamai Yoichi Konishi Takahisa Yamanouchi 《Virchows Archiv : an international journal of pathology》1989,415(1):51-60
Summary In order to clarify the histogenesis of clear cell sarcoma of tendons and aponeuroses (CCS), two cases of human and one nude mouse-transplanted CCS line were studied using an ultrastructural and enzyme cytochemical approach. Most of the tumour cells obtained from the primary and transplanted CCS demonstrated melanosomes in various stages of development within the cytoplasm, whereas no melanosomes could be identified in the metastatic CCS. However, cholinesterase and tyrosinase activities could be demonstrated not only in the melanotic primary and transplanted CCS but also in the amelanotic metastatic CCS. The results therefore support the hypothesis that CCS is a soft tissue tumour derived from the neural crest. 相似文献
55.
Kazuo Nagashima Hisako Endo Koko Sakakibara Yumiko Konishi Ko Miyachi Jau Jinn Wey Yoshiyuki Suzuki Jinichi Onisawa 《Pathology international》1976,26(1):115-132
An autopsy case of a 19-year-old boy who had shown typical gargoyle features, strictly consistent with mucopolysaccharidosis type II (Hunter's syndrome) was reported. Histologically, cytoplasmic vacuolar change was found In hepatocytes, sinusoidal epithelium of spleen, follicular cells of thyroid, Sertoli cells of testis, chromophobe cell of pituitary and generalized fibroblast-like cells including meninges, cardiac valve and periosteum. The vacuoles consisting of membrane-bound structures with flocculus protein-like material and occasional electron dense bodies on electron microscopy, were considered to be the site of mucopolysaccharide deposition by histochemical analysis. Deposition of lipid material consistent with so-called membranous cytoplasmic body was observed in the neurons of central, peripheral and autonomic nervous system. Hepatosplenomegaly could be explained by cytoplasmic deposition, but the cause of cardiomegaly remained further to be studied. Biochemically hepatic mucopolysaccharide was identified as heparan sulfate, while in the kidney dermatan sulfate and heparan sulfate were detected. The correlation between morphology and biochemistry, and between deposition and degeneration was discussed. 相似文献
56.
BACKGROUND: In order to know the relationships between mugwort pollinosis and oral allergy syndrome (OAS), an etiological study was performed at Muroran City, where mugwort is the most frequent cause of pollinosis. METHODS: Allergic rhinitis patients positive to serum IgE to birch, mugwort or grass pollen visited to the outpatient-clinic of Otorhinolaryngology of Muroran City General Hospital from 1998 to 2002, were studied by a questionnaire concerning a past-history of OAS. RESULTS: The prevalence of OAS was significantly higher in patients positive to serum IgE antibody specific to birch pollen or mugwort pollen than those negative to each pollen-specific antibody (birch; 54.5 vs 23.5%, p<0.0001, mugwort; 41.0 vs 21.5%, p<0.01). The main causative foods were fruits of rose family in patients with only birch pollen-specific IgE antibody, and were those other than rose family, such as kiwi, melon, orange, celery and onion in those with only mugwort pollen-specific IgE antibody. The patients group with high Lumiward score to mugwort pollen tended to include severe OAS cases. CONCLUSION: A close relationship was suggested between mugwort pollen sensitization and OAS. 相似文献
57.
Effects of -adrenoceptor stimulation on intracellular Ca2+ transients and tension were explored in rat ventricular muscles injected with aequorin. Adrenaline (0.05–5.0 M) and isoproterenol (0.05–1.0 M) increased the peak of twitch tension and accelerated relaxation. The former effect depended on Ca2+ concentration in Tyrode's solution ([Ca2+]o) and the stage of the experiment. Low concentrations of these drugs added to normal Tyrode's solution containing 2 mM [Ca2+]o did not potentiate twitch tension in the early stage of the experiments. These drugs increased the peak of the aequorin light signal and slightly accelerated the falling phase of the light especially the tail. Effects of dibutyryl-cyclic AMP (DB-cAMP) (0.1–5.0 mM) and 3-isobutyl-1-methylxanthine (IBMX) (0.01–0.5 mM) were qualitatively similar to those of adrenaline and isoproterenol.Isoproterenol applied at the peak of Na-deficient contracture decreased tension without significantly changing the light signal; similar results were obtained in the presence of ryanodine (1 M).The results were interpreted as follows: The increase of intracellular cAMP induced by -adrenoceptor stimulation facilitated Ca2+ uptake by sarcoplasmic reticulum (SR) and decreased Ca2+ sensitivity of contractile elements. Faster relaxation induced by cAMP was considered to be due to the decrease of Ca2+ sensitivity of contractile elements and faster Ca2+ uptake by SR. The slightly faster falling phase of light transient might be due to the faster Ca2+ uptake by SR, which predominates over the slower fall of [Ca2+]i induced by the decreased Ca2+ sensitivity of the contractile element. 相似文献
58.
T Ishihara F Uchino T Kamei T Yokota H Nakamura H Etoh E Suzuki S Konishi N Matsumoto 《Acta pathologica japonica》1978,28(1):139-155
A 7-year-old boy, who was diagnosed as typical SSPE by clinical data and laboratory findings, was autopsied and observed by immunofluorescent techniques, light and electron microscope. The morphological characteristics in the brain were perivascular cuffings with plasma cells, lymphocytes and mononuclear cells, gliosis and a large number of intranuclear and intracytoplasmic inclusions in the neuroglias and nerve cells. Various kinds of intranuclear inclusions were elucidated by electron microscopy and the fin structures of these inclusions were described in detail. At least five types of intranuclear inclusions were regarded as specific in SSPE. The presence of intranuclear inclusions of mononuclear cells in the lungs resembling the inclusions in the neuroglias suggested that the disease was not localized in the brain but could be disseminated throughout the body. 相似文献
59.
An association of 5,10-methylenetetrahydrofolate reductase (MTHFR) gene polymorphism and common carotid atherosclerosis 总被引:3,自引:0,他引:3
Kawamoto R Kohara K Tabara Y Miki T Doi T Tokunaga H Konishi I 《Journal of human genetics》2001,46(9):506-510
Plasma homocysteine (Hcy) concentration has been shown to be influenced by a mutation in the gene coding methylenetetrahydrofolate
reductase (MTHFR). Although plasma Hcy is related to atherosclerotic disorders, conflicting results have been reported about
the association between MTHFR gene polymorphism and sclerotic lesions of the common carotid arteries. The effect of age–gene interaction on carotid arterial
remodeling was investigated in elderly subjects with several risk factors for atherosclerosis. We evaluated sclerotic lesions
of the common carotid arteries by ultrasonography in 326 patients (mean age ± standard deviation, 73 ± 12 years) and studied
relations among the known risk factors for atherosclerosis, including MTHFR gene polymorphism and its interactions with age and sex. Of the 326 subjects studied, 136 had MTHFR genotype CC, 136 genotype CT, and 54 genotype TT. The three groups did not differ with respect to background factors such as age, history of cigarette smoking, blood pressure,
lipids or uric acid, or in the incidence of atherosclerotic diseases. Spearman's rank correlation revealed a significant relationship
between gender, age, Brinkman index, systolic blood pressure, triglycerides, HDL-cholesterol (HDL-C), uric acid, and MTHFR gene polymorphism. Multiple regression analysis using intima-media complex thickness (IMT) as a criterion variable and risk
factors, including MTHFR gene polymorphism as explanatory variables showed that MTHFR gene polymorphism (P = 0.039) was a significant independent explanatory variable for IMT, along with gender (male) (P < 0.001), age (P < 0.001), systolic blood pressure (SBP) (P = 0.047), total cholesterol (T-C) (P < 0.001), and HDL-C (P < 0.001). Furthermore, a general linear model analysis revealed that interaction between age and MTHFR gene polymorphism was significantly associated with IMT, independently of age, SBP, T-C, and HDL-C in male subjects. However,
age–gene interaction was not observed in female subjects. The findings of the present study confirm an association between
MTHFR gene polymorphism and common carotid atherosclerosis in the Japanese population and further support the role of risk factor–gene
interaction in common carotid atherosclerosis.
Received: May 14, 2001 / Accepted: June 8, 2001 相似文献
60.
Kuniaki Tanaka Yoshifumi Tomita Mari Tsuruta Fumiko Konishi Masao Okuda Kunisuke Himeno Kikuo Nomoto 《Immunopharmacology and immunotoxicology》1990,12(2):277-291
Chlorella vulgaris, an unicellular green algae, or its acetone-extract (Ac-Ex) were administered orally to Meth A tumor bearing BALB/c or (BALB/c DBA/2)F1 (CDF1) mice. When CDF1 mice were fed daily with 10% dried powder of Chlorella vulgaris (CVP) containing diet before and after Meth A tumor inoculation, the growth of rechallenged Meth A tumor was significantly suppressed in an antigen-specific manner. Augmentation of antitumor resistance was exhibited also by Winn assay using lymph node cells of tumor-bearing mice orally administered with CVP or Ac-Ex. Antigen-specific concomitant immunity in these mice were mediated by cytostatic T cells but not by cytotoxic T cells. Natural killer cells seemed not to contribute in antitumor resistance in this system. 相似文献