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1.
目的 观察环氧合酶-2(COX-2)抑制剂塞来昔布对白血病细胞株HL-60的化疗增敏作用,并对其机制进行初步探讨.方法 MTT法评估塞来昔布、多柔比星及二者联合对HL-60细胞的生长抑制效应;流式细胞术(FCM)检测细胞的凋亡;反转录聚合酶链反应(RT-PCR)检测Survivin基因的表达;Western blotting检测Survivin蛋白的表达.结果 多柔比星联合塞来昔布5和10μmol/L对HL-60细胞的半数抑制浓度(IC50)分别为0.25及0.16μg/ml,明显低于多柔比星单用的IC50(0.48μg/ml);多柔比星0.10μg/ml联合10 μmol/L塞来昔布下调Survivin基因mRNA及蛋白的表达;联合塞来昔布5和10 μmol/L的凋亡率[分别为(13.07±1.66)%及(22.36±1.84)%]较多柔比星0.10μg/ml单用[(5.72±1.25)%]明显增加(P<0.01).结论 COX-2抑制剂塞来昔布对白血病细胞株HL-60具有明显的化疗增敏作用,其初步机制涉及下调Survivin的表达,增加细胞凋亡.  相似文献   

2.
目的:研究麒麟菜海藻色素糖蛋白(seaweed pigment glycoprotein,SPG)对小鼠H22肝癌细胞增殖与凋亡的影响.方法:将不同浓度SPG与小鼠H22肝癌细胞共同培养,用MTT法测定癌细胞增殖活性.建立H22移植瘤小鼠肝癌模型,随机分为SPG高、中、低剂量组,对照组及环磷酰胺组.实验组小鼠每天分别给予不同剂量(100、50、10 mg/kg)的SPG灌胃,连续10 d,对照组同法给予等量生理盐水,环磷酰胺组小鼠腹腔注射20 mg/kg环磷酰胺,隔日一次.各组小鼠均于末次给受试物后24 h处死,取肿瘤组织用免疫组化法检测各组Bcl-2和Bax蛋白表达.结果:SPG高剂量组瘤细胞增殖活性(0.545±0.002)明显高于对照组(0.404±0.008)(P<0.05);SPG高剂量组Bcl-2和Bax蛋白阳性表达率分别为16.78%和38.1%,对照组分别为65.16%和4.68%,两组间的差异具有统计学意义(P<0.05).结论:SPG具有抑制小鼠H22肝癌细胞增殖、促进其凋亡的作用.  相似文献   

3.
目的 探讨增强子结合蛋白C/EBPα在白血病裸鼠体内的肿瘤抑制作用.方法 将30只BALB/c裸鼠随机分转染组(10只)、空载组(10只)、对照组(10只),建立皮下瘤模型,并将30只BALB/c裸鼠如上分组建立白血病模型,将C/EBPα稳定表达细胞株pEGFP-C/EBPα-K562、空载细胞株pEGFP-K562及白血病细胞株K562分别经皮下和尾静脉注射到相应组裸鼠体内,形成皮下瘤和血液病模型.观测皮下肿瘤的变化,应用TUNEL检测细胞的凋亡,瑞特-吉姆萨染色观察血液病模型裸鼠外周血和骨髓中白血病细胞增殖能力,RT-PCR检测增殖相关基因的表达.结果 皮下瘤模型中pEGFP-C/EBPα-K562组肿瘤质量及最大直径为(24±0.1)g和(11±2)mm,空载组和对照组分别为(5.1±0.3)g、(19±3)mm和(5.7±0.4)g、(23±3)mm(均P<0.05),TUNEL检测发现pEGFP-C/EBPα-K562组肿瘤细胞凋亡明显增加(P<0.05);血液病模型鼠外周血可见白血病细胞,pEGFP-C/EBPα-K562组白血病细胞增殖能力明显低于空载组和对照组,可见明显细胞分化现象,RT-PCR检测发现p53基因上调和c-myc基因下调.结论 增强子结合蛋白C/EBPα在白血病小鼠体内具有促进肿瘤细胞凋亡和抑制白血病细胞增殖的能力,并能促进白血病细胞分化.C/EBPα的白血病抑制作用可能是通过对相应基因的调控来实现.  相似文献   

4.
目的:通过分析表观弥散系数(ADC)值在低级别胶质瘤及高级别胶质瘤的差别,探讨ADC值在胶质瘤分级诊断中的价值.方法:经手术病理证实的14例低级别胶质瘤(Ⅰ、Ⅱ级)和20例高级别胶质瘤(Ⅲ、Ⅳ级)患者术前常规MRI检查、增强扫描检查及磁共振弥散加权成像(DWI)扫描.在工作站构建ADC图,分别测量肿瘤实质部分、瘤周水肿区和囊变坏死区以及相应对侧正常脑白质的ADC值,分析各测量区的ADC值与胶质瘤病理分级的关系.结果:低级别胶质瘤肿瘤实质部分ADC值[(1.47±0.18) ×10-3 mm2·s-1]明显高于高级别胶质瘤 [(0.97±0.18) ×10-3 mm2·s-1](P<0.01),相应对侧脑白质ADC值分别为(0.76±0.06)×10-3 mm2·s-1和(0.75±0.06) ×10-3 mm2·s-1;低级别胶质瘤肿瘤周围水肿区ADC值[(1.61±0.19) ×10-3 mm2·s-1]明显高于高级别胶质瘤 [(1.26±0.14) ×10-3 mm2·s-1](P<0.01),相应对侧脑白质ADC值分别为(0.74±0.04)×10-3 mm2·s-1和(0.77±0.06)×10-3 mm2·s-1;低级别胶质瘤囊变坏死区ADC值[(1.88±0.11) ×10-3 mm2·s-1]明显高于高级别胶质瘤[(1.31±0.14) ×10-3 mm2·s-1](P<0.01),相应对侧脑白质ADC值分别为(0.75±0.08) ×10-3 mm2·s-1和(0.73±0.06) ×10-3 mm2·s-1.脑胶质瘤肿瘤实质部分、瘤周水肿区、囊变坏死区的ADC值与肿瘤的恶性度呈负相关关系(r值分别为-0.821、-0.726和-0.919,P<0.01).结论:低级别胶质瘤与高级别胶质瘤瘤体实质区、瘤周水肿区、瘤体囊变坏死区ADC值有明显差异,ADC值测量可作为脑胶质瘤术前分级诊断的指标之一.  相似文献   

5.
目的 选用人类单核细胞白血病细胞株THP-1,体外加入紫草素二甲醚衍生物5,8-二甲基-2-β-羟基异戊酰紫草素(SK36),研究其在THP-1细胞株增殖和凋亡中的作用,并对其作用机制进行初步探讨.方法 CCK法检测SK36对THP-1细胞的增殖抑制作用;流式细胞术检测细胞早期凋亡标记Annexin V/PI及细胞凋亡通路Caspase活性;激光共聚焦显微镜观察细胞凋亡和坏死.结果 流式细胞术检测结果显示,1.02μg/ml SK36作用24、48 h后的细胞凋亡率分别为(40.61±2.13)%和(67.40 ±9.15)%,明显高于对照组的(16.97±0.61)%,差异有统计学意义(t=18.444,t=9.528,P<0.01);SK36诱导THP-1细胞凋亡且经历了Caspase-3的激活(F=323.61,P<0.01).结论 紫草素二甲醚衍生物SK36能有效地诱导THP-1细胞凋亡,其作用机制主要是激活Caspase-3.  相似文献   

6.
目的:观察肿瘤细胞裂解物致敏的树突状细胞(DC)联合吉西他滨(GEM)体外抑制肝癌HepG2 细胞系增殖的作用,为临床探索有效的肝癌综合治疗方案提供实验依据.方法:采用反复冻融法裂解HepG2 细胞,提取肿瘤细胞抗原后致敏DC,并以DC刺激自身T 细胞的增殖和活化.按不同处理因素分组:①空白对照组,只含空白培养液;②阴性对照组,只含HepG2 细胞;③单纯T 细胞组,将未经致敏DC 刺激的T细胞与靶细胞按20∶1 的比例接种;④单纯活化T 细胞组,将经致敏DC 刺激后的活化T 细胞与靶细胞按20∶1 的比例接种;⑤单纯GEM 处理组,靶细胞接种后在培养基中分别添加终浓度为50、100、150、200 μg·L-1 的GEM;⑥T细胞+GEM 处理组,在单纯T 细胞组的培养基中分别添加上述4个浓度梯度的GEM;⑦活化T 细胞+GEM 处理组,在活化T 细胞组的培养基中分别添加上述4个浓度梯度的GEM.MTT 法检测细胞杀伤率,流式细胞仪检测细胞凋亡率,观察应用T 细胞、不同浓度的GEM 以及两者联合应用对HepG2 细胞的体外杀伤效应.结果:空白对照组刺激指数(SI)为1.34,阴性对照组SI 为3.48,两者比较差异有统计学意义(P<0.01).与单纯T细胞组[(4.81±2.54)%]比较,单纯活化T 细胞组细胞杀伤率[(21.68±4.39)%]明显升高(P<0.01);与活化T细胞+50、100 和150 μg·L-1 GEM组比较,活化T细胞+200 μg·L-1 GEM组细胞杀伤率明显升高(P<0.05).单纯T 细胞组细胞凋亡率为(5.45±0.94)%,与阴性对照组 [(4.47±1.98)%]比较差异无统计学意义(P>0.05);活化T 细胞组细胞凋亡率为(14.32±1.16)%,与前两组比较差异有统计学意义(P<0.01).活化T细胞+100 μg·L-1 GEM组细胞凋亡率为(24.52±0.85)%,与其他各组比较差异均有统计学意义(P<0.05).结论:负载肿瘤细胞抗原的DC 可诱导出抗肿瘤的细胞毒性T细胞,活化的T细胞联合GEM 能显著提高其杀伤肿瘤细胞的作用.  相似文献   

7.
目的 探讨基质细胞衍生因子-1α(SDF-1α)、CD44v6(一种变异的CD44受体)在多发性骨髓瘤(MM)中的表达水平及其与病情进展的关系.方法 用酶联免疫吸附试验(ELISA)检测24例MM患者[14例初发和复发MM患者(初发和复发MM组),10例病情稳定MM患者(病情稳定MM组)]和15位健康骨髓移植供者或非肿瘤良性贫血患者(对照组)的骨髓单个核细胞(MNC)和骨髓基质细胞(BMSC)培养上清的SDF-1 α、CD44v6水平.结果 初发和复发MM组MNC培养上清的SDF-1α、CD44v6表达水平[(7232.41±2644.97)pg/ml和(34.34±13.20)ng/ml]显著高于病情稳定MM组[(2315.49±748.29)pg/ml和(15.69±5.28)ng/m1](t=6.25、t=7.82;均P<0.05)和对照组[(1149.52±636.06)pg/ml和(4.85±3.62)ng/ml](t=4.60、t=7.61;均P<0.05).病情稳定MM组SDF-1α、CD44v6水平显著高于对照绀(t=2.99、t=4.87;均P<0.05).9例初发和复发MM组的BMSC与人类骨髓瘤细胞系细胞U266加入rhIL-6进行混合培养后,SDF-1 α水平[(6180.25±5925.38)pg/ml]显著高于5例对照组BMSC[(1021.13±358.65)pg/ml]和9例初发和复发MM组[(1004.07±727.36)pg/ml](t=2.66、t=2.42;均P<0.05).而其他BMSC各组问的SDF-1α水平差异无统计学意义(P>0.05).SDF-1 α与CD44v6两者表达水平呈正相关(r=0.51,P=0.03).结论 SDF-1 α、CD44v6水平升高与MM的病情进展或发病有关,也可能与MM的肿瘤浸润过程有关;而这些体内过程可能需骨髓瘤细胞和BMSC与IL-6、SDF-1α和CD44v6等因素协同完成.  相似文献   

8.
目的 研究小干扰RNA片段(shRNA)对三氧化二砷(ATO)耐药的白血病细胞株K562/AS2细胞的Topo Ⅱα、TopoⅡβ基因表达及其功能的影响.方法 设计并合成针对Topo Ⅱα和TopoⅡβ基因序列的shRNA各3对,在脂质体的介导下转染K562/AS2细胞;用荧光实时定量聚合酶链反应(PCR)分析Topo Ⅱα、TopoⅡβmRNA的表达水平;流式细胞术检测Topo Ⅱα、TopoⅡβ蛋白表达.结果 针对Topo Ⅱα-shRNA、TopoⅡβ的shRNA作用于K562/AS2细胞24 h后,Topo ⅡαmRNA水平和蛋白水平最大下调为(78.22±0.01)%、(31.17±1.27)%(P<0.05),TopoⅡβmRNA水平和蛋白水平最大下调为(57.36 ±0.01)%、(23.98 ± 1.22)%(P<0.05).结论 转染24 h后针对TopoⅡ的shRNA可抑制对ATO耐药的白血病细胞株K562/AS2细胞TopoⅡ基因的表达.  相似文献   

9.
目的 研究低剂量地西他滨(DAC)联合伊马替尼(IM)对K562细胞株的增殖抑制作用及对bcr-abl表达的影响.方法 单药及两药联合后,通过四甲基偶氮唑蓝(MTT)法观察药物对K562细胞株的增殖抑制作用,流式细胞术检测药物对K562细胞株早期凋亡率及细胞周期,巢式反转录-聚合酶链反应(RT-PCR)半定量检测药物对K562细胞株bcr-abl mRNA表达.结果 DAC与IM单药对K562细胞的抑制作用呈浓度时间依赖性.两药联合用药抑制作用较单药组明显(F=43.947、165.580、321.193、296.101,均P<0.05),24、48、72 h各浓度组与对照组比较差异均有统计学意义(F=202.759、168.457、417.538,均P<0.05).DAC及IM单药作用药物对K562细胞株均使G,期细胞明显增多,IM0.2μmol/L作用于K562细胞株48 h可见6.7%早期凋亡细胞,IM 0.2 μmol/L联合DAC 4μmol/L早期凋亡细胞增加至8.4%.bcr-abl mRNA表达水平降低,DAC 4 μmol/L作用48 h后可降低K562细胞中bcr-abl mRNA表达(约14%),IM 0.2 μmol/L降低约40%,联合用药表达量明显降低(约60%).联合用药组与单药组比较差异有统计学意义(F=71.981,P<0.05).结论 DAC对K562细胞的增殖抑制作用与细胞周期阻滞、诱导凋亡及降低bcr-abl mRNA表达有关,两药联合可显著抑制K562细胞增殖.  相似文献   

10.
目的 探讨白血病肿瘤疫苗(简称瘤苗)主动免疫治疗及联合吲哚2,3双加氧酶(IDO)的抑制剂1-甲基色氨酸(1-MT),在白血病荷瘤小鼠治疗中的作用.方法 采用FBL-3细胞皮下注射建立荷瘤白血病小鼠模型;实验分为5组:正常对照组、PBS对照组、环磷酰胺(CTX)化疗组、单用瘤苗治疗组和瘤苗联合1-MT治疗组;观察各组小鼠的一般状况、肿瘤缓解率、肿瘤大小、转移情况及生存期.结果 PBS对照组小鼠活动迟缓,体质量(含瘤结节质量)比其余各组均高;单用瘤苗组和瘤苗联合1-MT组小鼠活动、进食正常,体质量与正常小鼠筹异不大;化疗组体质量明显减轻,出现脱毛、弓背、活动减少等,差异有统计学意义(F=57.71,P=000);单用瘤苗组和瘤苗联合1-MT组治疗相关死亡率明显低于化疗组(0,0,40%).瘤苗联合1-MT组完全缓解率与单用瘤苗组(61.1%、70.0%)比较,差异无统计学意义(χ2=0.221,P>0.05),但瘤苗联合1-MT组的复发率低于单用瘤苗组(0,36.36%);复发小鼠再应用1-MT,能明显抑制瘤结节的生长.单用瘤苗组和瘤苗联合1-MT组小鼠中位存活期明显高于化疗组和PBS对照组(χ2=52.13,P<0.01).各组小鼠整体瘤结节的变化比较差异有统计学意义(F=89.966,P=0.000).结论 白血病瘤苗在动物实验具有肯定的疗效,能明显抑制肿瘤的生长,延长小鼠生存时间,且副作用小.免疫治疗联合1-MT对白血病进行治疗,可以显著减少肿瘤的复发率;而免疫治疗有效后复发时应用1-MT,可以显著抑制肿瘤的生长.  相似文献   

11.
转炉炉壳热应力分析   总被引:5,自引:1,他引:4  
任学平  郭志强  邹家祥 《炼钢》2001,17(6):47-49
根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。  相似文献   

12.
Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

13.
The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.  相似文献   

14.
鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".  相似文献   

15.
张兴强  叶运福 《冶金设备》2005,(6):71-72,47
针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。  相似文献   

16.
17.
Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.  相似文献   

18.
通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。  相似文献   

19.
20.
In this paper is treated the fundamental problematic of the fracture of the diaphysis of the tibia and the therapeutic results after the conservative and operative treatment are confronted. Among 518 patients with 433 open fractures and 35 with closed fractures of the diaphysis of the tibia, successful treatment of more 2/3 was obtained in the period from 1968 to 1972. Following our casuistics and literature, whose results are similar, we find out that the average total treatment of the osteosynthesis of the fracture of the diaphysis was shortened for 2,5 months depending upon the type and the localisation of the fracture. Apolied methods of the operative and conservative and conservative treatment in relation to the velocity of the medical cure as well as to the extreme anatomical-functional results are analised. We noticed that osteosynthesis, made by the intermedullary nail and the extension of the canals or by a small AO table, by the achieved stability makes conditions of immediate motions and an early rehabilitation. Because of that it gives the best functional results.  相似文献   

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