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61.
目的:探讨血清可溶性细胞间粘附分子1(sICAM-1)的检测在大肠癌患者中的临床意义。方法:采用双抗体夹心ELISA法检测50例大肠癌、30例大肠良性病变及30例健康体检者血清sICAM-1水平,并比较大肠癌患者术前、术后,转移、无转移sICAM-1水平变化。结果:大肠癌患者血清sICAM-1水平明显高于良性病变患者及正常人(P<0.01);大肠癌患者术后血清sICAM-1水平较术前明显下降(P<0.01);有转移的大肠癌患者血清sICAM-1水平高于无转移的患者(P<0.01)。结论:血清sICAM-1水平与大肠癌的发生、发展密切相关,可作为大肠癌新的检测指标之一。  相似文献   
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63.
Increased numbers of tumour‐associated macrophages correlate with rapid tumour growth and metastasis in tumours. Thus, macrophage depletion has potential as a novel cancer therapy and positive responses have been reported in rodent tumour models. To investigate the effectiveness of this approach in dogs with cancer, we evaluated the effects of the macrophage‐depleting agent liposomal clodronate (LC) in dogs with soft‐tissue sarcoma (STS). To this end, we conducted a clinical trial of LC therapy in 13 dogs with STS. Repeated LC administration was well tolerated clinically. Preliminary examination of tumour biopsy sets from 5 of the 13 dogs demonstrated that the density of CD11b+ macrophages was significantly decreased after LC treatment. Circulating concentrations of interleukin‐8 were also significantly reduced. These preliminary studies are the first to suggest that LC can be used as a systemic macrophage‐depleting agent in dogs to reduce numbers of tumour‐associated macrophages.  相似文献   
64.
The recent research achievements about the mechanisms of beneficial health effects of tea polyphenols and the epidemiological investigation on anti-cancer,anti-cardiovascular diseases,and anti-obesity through tea consumption were reviewed.It is proved that reactive oxygen species is the main reason to induce cell mutation,DNA damage,obesity,high blood pressure and many kinds of cancers.Tea catechins and theaflavins have excellent bioactivity on scavenging ROS due to their characteristic structure feature of phenolic hydroxyl group,which means drinking tea could prevent diseases.Epidemidogical investigations also showed that tea consumption could reduce the risk of lung cancer,gastric cancer,bladder cancer,and so on.However,the frequency of tea drinking or tea consumption amounts significantly affected the prevention efficiency.The epidemiologic investigations also find that drink green tea,especial black tea is useful to modify the cardiovascular diseases.In vivo and vitro tests showed that tea supplement could moderate the metabolism of blood lipid and prevent obesity.These indicated that tea and tea extracts might reduce the risk of many diseases.  相似文献   
65.
Manzamine A, a member of the manzamine alkaloids, was originally isolated from marine sponges of the genus Haliclona. It was recently shown to have activity against pancreatic cancer cells, but the precise mechanism of action remained unclear. To further our understanding of the mechanism of action of manzamine A, chemogenomic profiling in the yeast S. cerevisiae was performed, suggesting that manzamine A is an uncoupler of vacuolar ATPases. Fluorescence microscopy confirmed this effect on yeast vacuoles, where manzamine A produced a phenotype very similar to that of the established v-ATPase inhibitor bafilomycin A1. In pancreatic cancer cells, 10 µM manzamine A affected vacuolar ATPase activity and significantly increased the level of autophagosome marker LC3-II and p62/SQSTM1 as observed by western blot analysis. Treatment with manzamine A in combination with bafilomycin A1 (inhibitor of autophagosome-lysosome fusion) did not change the levels of LC3-II when compared to cells treated with bafilomycin A1 alone, suggesting that manzamine A is a potential inhibitor of autophagy by preventing autophagosome turnover. As autophagy is essential for pancreatic tumor growth, blocking this pathway with manzamine A suggests a promising strategy for the treatment of pancreatic cancer.  相似文献   
66.
In continuation of our search for drug leads from Red Sea sponges we have investigated the ethyl acetate fraction of the organic extract of the Red Sea sponge Hyrtios species. Bioassay-directed fractionation of the active fraction resulted into the identification of three new alkaloids, hyrtioerectines D–F (1–3). Hyrtioerectines D–F belong to the rare marine alkaloids in which the indole and β-carboline fragments of the molecule are linked through C-3/C-3 of both moieties. The structures of the isolated compounds were established based on different spectroscopic data including UV, IR, 1D and 2D NMR (COSY, HSQC, and HMBC) and high-resolution mass spectral studies. The antimicrobial activity against several pathogens and the free radical scavenging activity of the compounds using DPPH reagent were evaluated. In addition, the growth inhibitory activity of the compounds against three cancer cell lines was also evaluated. Hyrtioerectines D–F (1–3) displayed variable antimicrobial, free radical scavenging and cancer growth inhibition activities. Generally, compounds 1 and 3 were more active than compound 2.  相似文献   
67.
Dicathais orbita is a large Australian marine gastropod known to produce bioactive compounds with anticancer properties. In this research, we used bioassay guided fractionation from the egg mass extract of D. orbita using flash column chromatography and identified fractions containing tyrindoleninone and 6-bromoisatin as the most active against colon cancer cells HT29 and Caco-2. Liquid chromatography coupled with mass spectrometry (LCMS) and 1H NMR were used to characterize the purity and chemical composition of the isolated compounds. An MTT assay was used to determine effects on cell viability. Necrosis and apoptosis induction using caspase/LDH assay and flow cytometry (PI/Annexin-V) and cell cycle analysis were also investigated. Our results show that semi-purified 6-bromoisatin had the highest anti-cancer activity by inhibiting cell viability (IC50 = ~100 µM) and increasing caspase 3/7 activity in both of the cell lines at low concentration. The fraction containing 6-bromoisatin induced 77.6% apoptosis and arrested 25.7% of the cells in G2/M phase of cell cycle in HT29 cells. Tyrindoleninone was less potent but significantly decreased the viability of HT29 cells at IC50 = 390 µM and induced apoptosis at 195 µM by increasing caspase 3/7 activity in these cells. This research will facilitate the development of these molluscan natural products as novel complementary medicines for colorectal cancer.  相似文献   
68.
为探究miR-142-3p在MCF-7细胞中作用机理,采用RNA免疫共沉淀技术和双荧光素酶报告基因技术筛选及验证miR-142-3p作用靶基因;蛋白质免疫印迹技术验证靶基因及其介导的PI3K-AKT-mTOR信号通路蛋白表达量及通路活性;应用实时荧光定量PCR验证靶基因PTEN对miR-142-3p调节关系。结果表明,miR-142-3p靶向调节AKT和PTEN表达;miR-142-3p过表达组中PI3K-AKT-mTOR通路活性显著降低;miR-142-3p抑制组中PI3K-AKT-mTOR通路活性显著上升;抑制PTEN表达显著提高miR-142-3p表达量。因此miR-142-3p靶向调节AKT和PTEN表达继而抑制PI3K-AKT-mTOR信号通路活性,PTEN与miR-142-3p存在调节关系。  相似文献   
69.
目的 探讨中医治疗肺癌放疗患者的用药规律。方法 检索中国知网数据库(CNKI)、万方数据库、维普数据库(VIP)、中国生物医学文献数据库(CBM)、PubMed数据库公开发表的治疗肺癌放疗患者的中药处方,运用频次分析、聚类分析、关联规则分析方法对收集的处方进行数据挖掘,分析其用药规律。结果 共收集到处方70张,涉及176味中药,使用频次共计890次;使用频次≥9的药物共32味;使用频次前三位的单味中药是黄芪、甘草、麦冬;使用频次前三位的药类是补虚药、清热药、化痰止咳平喘药;对32味药物进行聚类分析和关联规则分析,得出2个有效聚类群和13组药对,以补气药和滋阴药配伍为主,辅以补血活血、化痰止咳药。结论 治疗肺癌放疗患者的中药处方以补益药、清热药和止咳药为主,治法以益气养阴、清肺止咳为主。  相似文献   
70.
目的 探讨三物白散对Survivin-RNA基因沉默转染胃癌SGC-7901细胞凋亡、迁移的影响。方法 将实验分成6组:空白对照组、LV-RNAi 组、Survivin-RNAi-LV组、空白对照+中药组、LV-RNAi+中药组、Survivin-RNAi-LV+中药组;采用流式细胞仪检测各组细胞的凋亡,划痕实验检测各组细胞的迁移能力。结果 细胞凋亡率:Survivin-RNAi-LV组明显高于空白对照组和LV-RNAi组(P<0.05);Survivin-RNAi-LV+中药组与空白对照+中药组、LV-RNAi+中药组比较明显较高(P<0.05);Survivin-RNAi-LV+中药组高于Survivin-RNAi-LV组,差异具有统计学意义(P<0.05)。胃癌细胞的24 h迁移率:Survivin-RNAi-LV组明显低于空白对照组和LV-RNAi组(P<0.05);Survivin-RNAi-LV+中药组与空白对照+中药组、LV-RNAi+中药组比较,其结果明显低于后两组(P<0.05);Survivin-RNAi -LV+中药组与Survivin-RNAi-LV组比较,细胞迁移率明显降低,差异有统计学意义(P<0.05)。结论 Survivin基因沉默转染,增强了三物白散诱导胃癌SGC-7901细胞凋亡和抑制其迁移的作用。  相似文献   
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