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排序方式: 共有6106条查询结果,搜索用时 15 毫秒
21.
Tadaki Yasumura MD Toshikazu Akami Manabu Mitsuo Takahiro Oka Kazuo Naitoh Takara Yamamoto Hideo Honjyo Hiroji Okada 《Surgery today》1990,20(4):369-375
The ovarian and pituitary functions of 64 operable breast cancer patients undergoing adjuvant therapy with cytotoxic chemotherapy
and/or tamoxifen were investigated. The post menopausal patients, divided into 3 treatment groups, one with tamoxifen alone,
one with tamoxifen and chemotherapy and the other with chemotherapy alone had serum estradiol 17-β (E2) and progesterone levels
lower than the evaluable limits. Although there was no significant difference in the level of estrone sulfate (E1-S) between
these three groups, the level of lutainizing hormone (LH) and follicle stimulating hormone (FSH) in the patients treated with
tamoxifen alone and tamoxifen and chemotherapy were significantly lower than those treated with chemotherapy alone. The decrease
in gonadotropin levels induced by tamoxifen treatment was reversible as it appeared after the initiation of tamoxifen and
recovered after its cessation. In the premenopausal patients, a group treated with tamoxifen and chemotherapy had significantly
higher E1-S, E2 and progesterone levels and significantly lower gonadotropin levels than a group treated with chemotherapy
alone or one treated with a cyclophosphamide regimen. These increases in the levels of estrogen and progesterone were also
reversible, and induced by tamoxifen. Thus, adjuvant endocrinochemotherapy causes profound alteration in the hypothalamo-pituitary-ovarian
axis and therefore, monitoring a variety of hormonal levels is thought to be necessary for assessing the consequences of adjuvant
therapy in breast cancer patients, especially in premenopausal patients using tamoxifen. 相似文献
22.
Naoki Hori Hakuo Takahashi‡ Takeshi Okanoue Yoshihiko Sawa Takashi Mori Shiro Takami Manabu Yoshimura† Kei Kashima 《Clinical and experimental pharmacology & physiology》1995,22(8):506-511
1. Endothelium-derived nitric oxide (NO) is a potent vasodilator. Because the body oxidizes it to nitrate ions, NO3-, measurement of the serum concentration and the urinary excretion of NO3- may be an index for endogenous NO. We investigated the role of NO on hyperdynamic circulation in cirrhotic and partial portal vein-ligated rats by measuring NO3. 2. Liver cirrhosis was induced by administration of thioacetamide. Systemic and splanchnic haemodynamics and splenic-systemic shunting were determined by tracer microspheres. The concentration of NO3- was measured by using high-performance liquid chromatography with an anion-column. 3. We found that systemic and splanchnic hyperdynamic circulation existed to almost the same extent in cirrhotic and in portal vein-ligated rats as compared to the controls and sham-operated rats, respectively. Splenic-systemic shunting was markedly greater in portal vein-ligated rats than in cirrhotic rats. 4. Serum NO3- levels and urinary excretion of NO3- in cirrhotic rats tended to increase as compared to the controls. On the other hand, the levels in portal vein-ligated rats were significantly increased as compared to those of the sham-operated rats, and were significantly and negatively correlated to the splanchnic arterial resistance and total vascular resistance. The amount of urinary excretion of NO3- significantly correlated to splenic-systemic shunting (r = 0.61, P<0.05) only in portal vein-ligated rats. 5. We suggest that these high levels of NO3- in portal vein-ligated rats relate to the extensive formation of porto-collateral vasculature or acute changes in systemic and splanchnic haemodynamics due to portal vein-ligation. 相似文献
23.
Yamamoto K Okamura A Minagawa K Yakushijin K Urahama N Gomyo H Shimoyama M Itoh M Matsui T 《Cancer Genetics and Cytogenetics》2003,147(2):128-133
Follicular lymphoma is characterized genetically by t(14;18)(q32;q21), whereas t(18;22)(q21;q11), a rare variant form of t(14;18), has been preferentially observed in chronic lymphocytic leukemia (CLL). We describe here an unusual case of follicular lymphoma with a t(18;22)(q21;q11), that progressed to diffuse large cell lymphoma with a novel t(2;6)(p12;q23). Spectral karyotyping revealed that add(2)(p12) and add(6)(q23) were derived from a t(2;6)(p12;q23). Fluorescence in situ hybridization analysis confirmed rearrangements of the BCL2 gene at 18q21 and the BCL6 gene at 3q27. Our results indicate that a reciprocal translocation involving 6q23 could be implicated in the progression of follicular lymphoma and that t(18;22) may have a specific role in the pathogenesis of follicular lymphoma as well as CLL. 相似文献
24.
25.
Enhanced expression of type I interferon and toll-like receptor-3 in primary biliary cirrhosis 总被引:6,自引:0,他引:6
Takii Y Nakamura M Ito M Yokoyama T Komori A Shimizu-Yoshida Y Nakao R Kusumoto K Nagaoka S Yano K Abiru S Ueki T Matsumoto T Daikoku M Taniguchi K Fujioka H Migita K Yatsuhashi H Nakashima M Harada M Ishibashi H 《Laboratory investigation; a journal of technical methods and pathology》2005,85(7):908-920
26.
Osteopontin affects the persistence of beta-glucan-induced hepatic granuloma formation and tissue injury through two distinct mechanisms 总被引:4,自引:0,他引:4
Morimoto J Inobe M Kimura C Kon S Diao H Aoki M Miyazaki T Denhardt DT Rittling S Uede T 《International immunology》2004,16(3):477-488
Osteopontin (OPN) plays a pivotal role in various immune responses and inflammatory diseases. OPN is expressed in various granulomatous diseases; however, the cellular and molecular role of OPN in these diseases is not well known. We analyzed the role of OPN in a beta-glucan-induced hepatic granuloma model. First, we found that neither OPN deficiency nor overexpression of OPN affected the number and the size of hepatic granulomas at day 7, indicating that OPN is not involved in the formation of hepatic granulomas at the early stages. Importantly, OPN did not influence the liver tissue damage as defined by alanine aminotransferase and aspartate aminotransferase levels at early stages. Second, OPN deficiency resulted in the reduction of IL-12 and IFN-gamma production at early stages. Third, at late stages, OPN deficiency resulted in a decrease in the number and size of hepatic granulomas, and a reduction of liver tissue injury. This was due to the reduction of the cellular recruitment including macrophages, CD4 T cells and dendritic cells into the liver, and the reduction of tumor necrosis factor (TNF)-alpha production in the liver. In contrast, overexpression of OPN resulted in the persistence of granuloma formation. These data suggest that OPN affects the persistence of hepatic granuloma formation. Our results indicate that OPN up-regulates the production of IL-12 and IFN-gamma within the granulomas at early stages, and OPN has an additional role in the regulation of cellular recruitment and TNF-alpha production at late stages that determine the severity of liver tissue injury. 相似文献
27.
We found a glutamine/arginine polymorphism at codon 349 of the hBUBR1 gene, encoding a protein kinase required for spindle assembly checkpoint function. The observed heterozygosity was estimated
to be 45% in the Japanese population. This polymorphism may be helpful for genetic studies of many cancer types in which chromosomal
instability is observed.
Received: October 19, 1998 / Accepted: October 24, 1998 相似文献
28.
29.
Manabu Daikoku Keisuke Nakata Keisuke Hamasaki Akio Ido Kazuhiko Nakao Yuji Kato Michiaki Koga Michitami Yano Shigenobu Nagataki 《Journal of medical virology》1995,47(2):184-188
Hepatitis B virus (HBV), with a G-to-A point mutation at nucleotide 83 in the precore region (mutant HBV83), accounts for most cases of hepatitis B e antigen (HBeAg)-defective HBV. However, it is still not clear how mutant HBV83 is associated with HBe seroconversion. Twenty-six HBeAgpositive patients with chronic hepatitis B who received oral prednisolone (30 mg/day) for 3 weeks were studied to clarify the prevalence of mutant HBV83 during the treatment using polymerase chain reaction with a restriction fragment length polymorphism assay. Twelve (46%) patients seroconverted to anti-HBe 1 year after treatment, whereas 14 (54%) did not. The proportion of mutant HBV83 to whole HBV remained unchanged in both groups during an acute exacerbation induced by withdrawal of corticosteroids. Among 12 anti-HBe-0seroconverted patients, five (56%) of nine patients with only wild-type HBV at baseline developed detectable levels of mutant HBV83 while all three patients with a mixed viral population of wild-type HBV and mu tant HBV83 at baseline developed a higher pro portion of mutant HBV83 one year after treat ment. In contrast, these changes were observed in only one (14%) of seven who failed to seroconvert. The results indicate that a flare-up of hepa titis precedes emergence or selection of mutant HBV83, followed by HBe seroconversion in patients with chronic hepatitis B. © 1995 WiIey-Liss, Inc. 相似文献
30.
Numerical aberrations of chromosome 9 in bladder cancer. A possible prognostic marker for early tumor recurrence 总被引:3,自引:0,他引:3
Tsukamoto M Matsuyama H Oba K Yoshihiro S Takahashi M Naito K 《Cancer Genetics and Cytogenetics》2002,132(1):41-45
Bilharzial bladder cancer is one of the most common types of malignancy in both men and women in several developing countries including Egypt. It has several unique clinical, epidemiological, and histological characteristics, suggesting that it is an entity distinct from bladder cancer seen in Western countries. Genetic alterations in bilharzial-related bladder cancer have been studied infrequently, especially in the advanced stages of disease, that is, T3 and T4 classifications. The objective of this study was to extend establishing the baseline cytogenetic profile of this type of malignancy to early T1 and T2 classifications. For this purpose, fluorescence in situ hybridization was applied to interphase nuclei of frozen-stored samples with biotinylated repetitive DNA probes specific for all chromosomes to detect numerical chromosome changes in 35 patients presenting with relatively early-stage pT1 and pT2 disease. Eleven cases had squamous cell carcinoma (SCC) and 24 had transitional cell carcinoma. Six of 24 transitional cell carcinomas had diploid chromosome counts with all the probes. Numerical chromosome aberrations were detected in 18 cases (75%). In 12 cases, a loss of chromosome 9 was observed. In three cases, an additional loss of chromosome 17 was detected. One case demonstrated a loss of chromosome 10, whereas another two cases showed a gain of chromosome 7, next to a loss of chromosome 9. Loss of chromosome Y was observed in nine of the 27 male cases studied (33.3%), in which only one case showed an abnormality whereas four cases were detected next to loss of chromosome 9, and one case showed gain of chromosome 7. Five cases showed loss of chromosome 19 whereas gain of chromosome 4 was detected in two cases. Two of 11 samples of SCC had normal diploid chromosome counts with all the probes used. In four of 11 cases (36.4%) underrepresentation of chromosome 9, compared with the other chromosomes, was detected. An additional loss of chromosome 17 and gain of chromosome 7, next to loss of chromosome 9, was detected in three cases. One case showed loss of chromosome 17 as the only numerical aberration. Loss of the Y chromosome was detected in three cases of which one case had gain of chromosome 7 and one case had loss of chromosome 19. No correlation was found between any of the clinicopathologic parameters examined in this study and the presence or absence of any numerical chromosomal aberrations except for the significant association between schistosomal history and loss of Y chromosome (P=0.007). 相似文献