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Mutations in the transforming growth factor beta type II receptor (TGFbetaRII) gene have been detected in several human cancer types exhibiting microsatellite instability. Using intron primers previously reported for examination of the entire coding region of the TGFbetaRII gene, 29 sporadic gastric cancers were screened with non-radioactive single strand conformation polymorphism and subsequent DNA sequencing analysis. Mutations of the TGFbetaRII gene were detected in three out of 29 tumors (10%). Two cases showed deletions in a polyadenine tract in both alleles and was positively associated with replication error. One case had an insertion of GA dinucleotide sequence in one allele. Mutations of the TGFbetaRII gene were restricted to exon 3 and other coding regions were not affected. Loss of heterozygosity was detected by analyzing a polymorphic site in intron 2. Three out of nine (33%) informative cases, which were all of intestinal type and advanced cases, showed loss of heterozygosity but neither TGFbetaRII mutation nor replication error was found in these cases. Immunoreactivity of TGFbetaRII in tumor tissues was reduced to a different extent in the gastric cancer with genetically abnormal transforming growth factor. Although the numbers studied are small, homozygous (A)10 deletion or loss of heterozygosity of TGFbetaRII is involved in tumorigenesis and progression of at least some part of sporadic gastric cancer.   相似文献   
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A 54-year-old man was treated with weekly 24-h infusion of high-dose 5-fluorouracil (2600 mg/m2) and leucovorin (100 mg/m2) for metastatic colon cancer. At first, he tolerated the treatment well and no significant toxicity was identified. After a total of eight courses of treatment, a stable disease was observed, but mild shortness of breath was found on occasion. The patient had no previous history of cardiac disease and the heart performance assessed by left ventricular ejection fraction before treatment was normal. Unfortunately, acute pulmonary edema with lethal cardiogenic shock occurred during the ninth course of treatment, in spite of intensive medical treatment. The chest X-ray showed extreme cardiomegaly. Repeated assessment of his heart function by echocardiogram and ventricular ejection fraction revealed a very poor cardiac performance. Toxic cardiogenic shock during weekly 24-h infusion of high-dose 5-fluorouracil and leucovorin is extremely rare. To the best of our knowledge, no case has been reported in the English literature. We report a case and the relevant literature about the incidence, clinical picture and possible pathophysiology on 5-fluorouracil-related cardioxicity is reviewed.   相似文献   
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Composite regulatory signature database (CRSD), a self-developed comprehensive Web server for composite regulatory signature discovery, used to compare the published microarray data with our data on patients with uterine leiomyoma treated with or without GnRH analogue (GnRH-a), revealed that the focal adhesion, mitogen-activated protein kinase (MAPK), CXC chemokine receptor 4/stromal-derived factor-1 (CXCR4/SDF-1), T-cell receptor, integrin, vascular endothelial growth factor (VEGF), GnRH, and transforming growth factor-beta (TGF-beta) signaling pathways are highly expressed in uterine leiomyoma and significantly down-regulated after GnRH-a treatment. According to the results these signaling pathways could be involved in inflammation, proliferation, and remodeling processes of leiomyoma development and possibly in the regression of leiomyoma after GnRH-a treatment, which might improve our understanding of the mechanisms of leiomyoma formation and help us to find novel drug targets or specific markers for diagnosis and prognosis in uterine leiomyoma.  相似文献   
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Anisomeles indica (L.) Kuntze (Labiatae), is a traditional anti-inflammatory herb used in Taiwan. The aqueous and methanolic extracts of whole plants, leaves, flowers and stems; and chloroform and n-butanol fractions of methanol extract, from A. indica were investigated for their anti-inflammatory activity on murine peritoneal macrophages. In addition, the tumor cells proliferation inhibition activities of these extracts were also evaluated against a panel of tumor cell lines such as Colon 205, PC 3, HepG2 and MCF 7. Treatment with A. indica extracts did not reduce cell viability at any dose used. However, all the extracts significantly inhibited the enhanced production of NO radicals, and pro-inflammatory cytokines (TNF-alpha, and IL-12) induced by LPS/IFN-gamma in a dose-dependent manner. Furthermore, methanolic extracts of leaves and flowers significantly and dose-dependently arrest mitogen-stimulated spleen cells in G0/G1 stage, in addition to their cell proliferation inhibition against Colon 205, MCF 7 and PC 3 by 94, 82; 98, 71; 82, 98%, respectively, at 200 microg/mL concentration. This is the first report on A. indica extracts for their growth inhibitory activities, against inflammatory mediator production, and human tumor cell lines, colon, prostate, hepatoma and breast cells proliferation.  相似文献   
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目的探讨腹腔镜外科技术在胃肠道肿瘤手术中的应用。方法经电视腹腔镜行胃肠道肿瘤手术18例,其中右半结肠切除术4例,横结肠癌根治术3例,乙状结肠癌根治术5例,乙状结肠癌姑息切除术并肝转移癌电凝固化1例,胃癌术后复发转移行探查活检1例,胃巨大恶性淋巴瘤行探查活检1例,晚期回肠癌行小肠侧侧吻合术1例,乙状结肠腺瘤切除术2例。结果均获成功,无中转开腹,手术时间平均165.0分钟。术后平均31.2小时胃肠功能恢复,无并发症发生,术后平均住院8.2天。13例切除肿瘤的结肠癌术后随访2月~30月,仅1例横结肠癌术后23月出现肺转移。结论腹腔镜胃肠肿瘤手术损伤小、恢复快、胃肠干扰小、术后疼痛轻,值得进一步探索开展。  相似文献   
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Human natural killer (NK) cells are large granular lymphocytes that constitutively express functional forms of the interleukin-2 receptor (IL-2R) and lyse tumor and virally infected cells without prior sensitization. NK cells with high density expression of CD56 (CD56bright) express the high affinity IL-2R and proliferate in response to low (picomolar) concentrations of IL-2. CD56dim NK cells express the intermediate affinity IL-2R and demonstrate enhanced cytotoxic activity without proliferation in response to high (nanomolar) concentrations of IL-2. In the present study, we characterized IL-10R expression on human NK cells and the functional consequences of IL-10 binding directly to highly purified subsets of CD56bright and CD56dim NK cells. Binding studies using 125I-IL-10 indicated that resting human NK cells constitutively express the IL-10 receptor protein at a surface density of approximately 90 receptor sites per cell, with a kd of approximately 1 nmol/L. Alone, IL-10 did not induce proliferation of CD56bright or CD56dim NK cell subsets. However, at low concentrations (0.5 to 5 ng/mL), IL-10 significantly augmented IL-2-induced proliferation of the CD56bright NK cell subset mediated via the high-affinity IL-2R. In the absence of IL-2, IL-10 was able to induce significant NK cytotoxic activity against NK-resistant tumor cell targets in both subsets of NK cells in a dose-dependent fashion. Furthermore, the combination of IL-10 and IL-2 had an additive effect on NK cytotoxic activity, whereas that of IL-10 and IL-12 did not. Production of interferon-gamma, tumor necrosis factor-alpha, and granulocyte-macrophage colony-stimulating factor by IL-2-activated NK cells was also significantly enhanced by IL-10. Neither resting nor activated human NK cells appear to produce human IL-10 protein. In summary, NK cells constitutively express the IL-10R protein in low density, and the functional consequences of IL-10 binding directly to human NK cell subsets appear to be stimulatory and dose-dependent. In contrast to its direct effects on human T cells and monocytes/macrophages, IL-10 potentiates cytokine production by human NK cells.  相似文献   
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