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71.
目的:研究构建miRNA-375慢病毒表达载体并转染结直肠癌细胞,探讨其对结直肠癌细胞生物学特性的影响.方法:采用qRT-PCR法检测结直肠癌细胞株中miRNA-375表达水平.构建FUA-ZMCS-EF1-EGFP-miR-375/inhibitor慢病毒表达载体,建立稳定过表达miRNA-375及其抑制剂的HCT-116亚细胞系,体外观察细胞生长速度并绘制生长曲线,流式细胞仪检测细胞凋亡率,划痕实验检测miRNA-375对HCT-116细胞迁移能力的影响,Western blot法检测miRNA-375对细胞内ERK磷酸化水平的影响.结果:结直肠癌细胞株中miRNA-375低表达不但能促进细胞生长、抑制细胞凋亡,而且能促进细胞内ERK磷酸化水平、增加细胞迁移力和侵袭力.结论:结直肠癌miRNA-375发挥抑癌基因的作用,为miRNA-375在结直肠癌基因诊断及治疗中的应用提供了实验依据.  相似文献   
72.
目的:评价厄洛替尼治疗EGFR野生型NSCLC的疗效及安全性.方法:31名Ⅲ/Ⅳ期或术后复发,不携带EGFR敏感突变(外显子18、19、21)的NSCLC患者服用厄洛替尼(150 mg/d).结果:术后再发的,EGFR野生型的,Ⅲ期或Ⅳ期患者服用厄洛替尼(150 mg/d),1例完全缓解,4例部分缓解,8例疾病稳定.缓解率为17.2%,疾病控制率为44.8%.皮疹是最常见的不良反应(80.6%).有两名患者出现了间质性肺病.但所有这些不良反应均为可逆的,没有出现治疗相关死亡.中位无进展生存时间及中位生存时间分别为2.1个月与7.7个月.结论:厄洛替尼可能会成为化疗耐受的EGFR野生型NSCLC患者的一个替代方案.  相似文献   
73.
Ji J  Zhang L  Wu YY  Zhu XY  Lv SQ  Sun XZ 《Leukemia & lymphoma》2006,47(12):2617-2624
Using K562 and HL60 cell lines, we have investigated the anti-tumoral activity of d-limonene, a monocyclic monoterpene, in human leukemia cells. Apoptosis was evaluated by Hoechst staining and by the annexin V/propidium iodide binding assay. d-Limonene induced apoptosis in a dose- and time-dependent manner in both cell lines. Our findings and data, demonstrating an increase in Bax protein expression, the release of cytochrome c from mitochondria, and an increase in caspase-9 and cleaved caspase-3, but not caspase-8, after the treatment of d-limonene, all suggest that the mitochondrial death pathway is primarily involved in the development of d-limonene-induced apoptosis.  相似文献   
74.
目的:初步探讨2、4 Gy X射线照射后人肺腺癌A549细胞miR-505体内、外表达的变化及意义.方法:2、4 Gy X射线分别照射体外培养的A549细胞,以实时定量PCR(RT-qPCR)法检测A549细胞中miR-505表达水平.分别将0、2与4 Gy X射线照射后的A549细胞经尾静脉注射裸鼠制备裸鼠肺转移动物模型,检测裸鼠肺组织及血清中miR-505的表达水平.统计分析采用SPSS 19.0软件.结果:2 Gy X射线照射A549细胞后1、2、12、及24 h,miR-505表达均显著升高(升高倍数分别为:3.09、1.82、2.19及1.24倍,P<0.01);4 Gy X射线照射A549细胞后1、2、12 h,miR-505表达亦均显著升高(升高倍数分别为:2.99、2.06、1.86倍,P<0.01).0、2、4 Gy X线照射组裸鼠肺组织中均可检测到miR-505表达显著升高(升高倍数分别为:9.28、16.55及6.84倍,P<0.05);miR-505在血清中表达水平0 Gy和2 Gy组分别为5.33和3.78,与对照组相比显著升高(P<0.05).结论:2、4 Gy X射线照射可增加A549细胞miR-505的体内、外表达水平,可能与增强A549细胞体内、外侵袭转移能力相关.  相似文献   
75.
76.

Background

Accumulating evidence demonstrates that complex diseases may arise from cooperative effects of multiple dysfunctional miRNAs. Thus, identifying abnormal functions cooperatively regulated by multiple miRNAs is useful for understanding the pathogenesis of complex diseases.

Methods

In this study, we proposed a multistep method to identify dysfunctional miRNA-mRNA regulatory modules (dMiMRMs) in a specific disease, in which a group of miRNAs cooperatively regulate a group of target genes involved in a specific function. We identified dysfunctional miRNAs, which were differentially expressed and inversely regulated most of their target genes, by integrating paired miRNA and mRNA expression profiles and miRNA target information. Then, we identified cooperative functional units, in each of which a pair of miRNAs cooperatively repressed function-enriched and highly interconnected target genes. Finally, the cooperative functional units were assembled into dMiMRMs.

Results

We applied our method to glioblastoma (GBM) and identified GBM-associated dMiMRMs at the population, subtype, and individual levels. We identified 5 common dMiMRMs using all GBM samples, 3 of which were associated with the prognosis in patients with GBM and were better predictors of prognosis than were miRNAs or mRNAs alone. By applying our approach to GBM subtypes, we found consistent dMiMRMs across GBM subtypes, and some subtype-specific dMiMRMs were observed. Furthermore, personalized dMiMRMs were identified, suggesting significant individual differences in different patients with GBM.

Conclusions

Our method provides the capability to identify miRNA-mediated dysfunctional mechanisms underlying complex diseases.  相似文献   
77.
目的:探讨与中性粒细胞异常增殖相关的BCR/ABL-慢性白血病的临床特征.方法:报告3例不同类型与中性粒细胞异常增殖相关的BCR/ABL-慢性白血病并结合文献进行讨论.结果:3例均为老年男性,表现为以中性粒细胞为主的白细胞异常增多、BCR/ABL融合基因阴性.例1诊断为慢性中性粒细胞白血病(CNL),脾大,外周血以成熟中性粒细胞增高为特征,胞浆内中毒颗粒易见,无明显病态造血,中性粒细胞碱性磷酸酶(NAP)染色强阳性,骨髓粒系增生明显活跃.例2诊断为不典型慢性髓细胞白血病(aCML),血涂片示不成熟粒细胞比例增高伴粒系病态造血,尤其核染色质异常浓聚更为明显,骨髓象表现为髓系增生和病态造血,原始细胞轻度增多.例3诊断为慢性粒单核细胞白血病(CMML),外周血成熟单核细胞数量和比例异常偏高,粒系病态如核分叶过多、环状核和假性Pelger-Huet畸形等易见,骨髓髓系增生明显活跃伴病态造血,无原始细胞增多.结论:中性粒细胞异常增殖相关的BCR/ABL-慢性白血病较为少见,易于误诊,细胞形态学特征是诊断BCR/ABL-慢性白血病的基础.临床表现、多种实验室检查结果尤其是分子生物学等有助于正确诊断这类疾病.  相似文献   
78.
CEACAM1和VEGF在宫颈鳞癌组织中的表达及临床意义   总被引:1,自引:0,他引:1  
目的 研究CEACAM1、VEGF和微血管密度(MVD)在宫颈癌组织中的表达与子宫颈癌的生长、浸润及转移的关系.方法 采用免疫组化二步法检测76例子宫颈鳞癌(高分化22例、中分化25例、低分化29例),15例宫颈上皮内瘤变(CIN)和10例正常宫颈组织中CEACAM1、VEGF的表达及CEACAM1标记的微血管密度.结果 在宫颈鳞癌组CEACAM1、VEGF及CEACAM1标记的MVD的表达与正常宫颈组织和CIN组差异有统计学意义(P<0.05),并且在宫颈鳞癌中的表达与盆腔淋巴结转移、组织学分级及FIGO分期有关(P<0.05),而与年龄无关(P>0.05).VEGF在宫颈癌中的表达与MVD的表达关系密切(P<0.01).结论 CEACAM1是一种肿瘤抑制因子,但其在肿瘤新生血管生成中起促进作用,VEGF可能在CEACAM1促进新生血管形成的过程中起到协同作用.  相似文献   
79.
This study aims to investigate the effect of ultrasound (US)-guided coaxial puncture needle in puncture biopsy of peripheral pulmonary masses. In this retrospective analysis, 157 patients who underwent US-guided percutaneous lung biopsy in our hospital were divided into a coaxial biopsy group and a conventional biopsy group (the control group) according to the puncture tools involved, with 73 and 84 patients, respectively. The average puncture time, number of sampling, sampling satisfaction rate, puncture success rate and complication rate between the 2 groups were compared and discussed in detail. One hundred fifty-seven patients underwent puncture biopsy, and 145 patients finally obtained definitive pathological results. The overall puncture success rate was 92.4% ([145/157]; with a puncture success rate of 97.3% [71/73] from the coaxial biopsy group and a puncture success rate of 88.1% [74/84] from the conventional biopsy group (P < .05). For peripheral pulmonary masses ≤3 cm, the average puncture time in the coaxial biopsy group was shorter than that in the conventional biopsy group, and the number of sampling, sampling satisfaction rate and puncture success rate were significantly higher than those in the conventional biopsy group (P < .05). There was no significant difference in the complication rate between the 2 groups (P > .05). For peripheral pulmonary masses >3 cm, the average puncture time in the coaxial biopsy group was still shorter than that in the conventional biopsy group (P < .05). The differences between the 2 groups in the number of sampling, satisfaction rate of the sampling, the success rate of puncture and the incidence of complications were not significant (P > .05). US guided coaxial puncture biopsy could save puncture time, increase the number of sampling, and improve the satisfaction rate of sampling and the success rate of puncture (especially for small lesions) by establishing a biopsy channel on the basis of the coaxial needle sheath. It provided reliable information for the diagnosis, differential diagnosis and individualized accurate treatment of lesions as well.  相似文献   
80.
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