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1.
目的:探讨RNA干扰技术沉默葡萄糖调节蛋白78(GRP78)基因对人卵巢癌细胞耐药性的影响,阐明GRP78基因沉默逆转肿瘤细胞耐药性的生物学机制.方法:构建pSilencerTM3.0-H1-GRP78 siRNA重组质粒,脂质体介导转染至SKOV3/DDP细胞;RT-PCR和Western blotting法检测GRP78基因的蛋白的表达;Western blotting法检测caspase-4和caspase-3蛋白表达;流式细胞术检测细胞凋亡率.结果:转染GRP78 siRNA重组质粒的SKOV3/DDP细胞GRP78基因和蛋白表达较转染空质粒组明显降低(P<0.05);加用顺铂后,转染GRP78 siRNA重组质粒细胞组较未转染GRP78 siRNA重组质粒细胞组caspase-4和caspase-3表达明显增加(P<0.05),细胞凋亡率也明显增加(P<0.05).结论:抑制GRP78基因表达能通过上调caspase-4和caspase-3表达及增加顺铂诱导的SKOV3/DDP细胞凋亡率,降低SKOV3/DDP细胞对顺铂的耐药性.  相似文献   

2.
目的:观察20(s)-原人参二醇(PPD)对体外培养人宫颈癌Siha细胞中caspase-9和caspase-3转录表达的影响,以及caspase-3的活化形式cleaved caspase-3含量的变化,阐明其诱导Siha细胞凋亡的机制.方法:体外培养人宫颈癌Siha细胞,将其分为阴性对照组(乙醇)和实验组(20 μg·L-1 PPD),分别用乙醇和PPD处理体外培养的宫颈癌Siha细胞,48 h后流式细胞仪检测细胞的凋亡峰,半定量RT-PCR、Western blotting和免疫细胞化学染色方法检测PPD处理后Siha细胞中caspase-9和caspase-3基因的转录与表达水平.结果:与阴性对照组比较,20 μg·L-1 PPD处理48 h后,Siha细胞凋亡率增加(P<0.05),Siha细胞中caspase-9与caspase-3转录水平升高(P<0.01),表达上调(P<0.01),caspase-3的活化形式cleaved caspase-3含量增加(P<0.01).细胞免疫化学检测可见实验组细胞出现棕色颗粒.结论:PPD可促进人宫颈癌Siha细胞凋亡,其机制与激活caspase家族级联反应有关.  相似文献   

3.
目的:观察姜黄素(Cur)联合人类细胞因子诱导的杀伤(CIK)细胞在体外对人卵巢癌浆液性囊腺癌细胞SKOV-3的增殖抑制作用,探讨其协同抗肿瘤作用及其可能机制.方法:诱导脐血CIK细胞,将SKOV-3细胞随机分为Cur组、CIK细胞组和Cur联合CIK细胞组,MTT法测定各组细胞的增殖抑制率,RT-PCR检测各组细胞Fas相关死亡结构蛋白Fas、Fas相关死亡结构蛋白(FADD)和Caspase-3 mRNA的表达.结果:与Cur组和CIK细胞组比较,Cur联合CIK细胞组SKOV-3细胞增殖抑制率增大,并且随时间的延长或剂量的增加,增殖抑制率亦增加,在效靶比为12.5∶1,20 μmol·L-1 Cur作用48 h时,SKOV-3细胞增殖抑制率达到76.2%;Cur联合CIK细胞组与Cur组和CIK细胞组比较,SKOV-3细胞Fas及Caspase-3的mRNA表达水平增加(P<0.05),Cur组、CIK细胞组和Cur联合CIK细胞组SKOV-3细胞FADD-mRNA表达无明显变化.结论:CIK细胞与Cur合用具有协同抗肿瘤作用,其效应可能与促进SKOV-3细胞Fas及Caspase-3的mRNA表达有关.  相似文献   

4.
目的:研究低剂量电离辐射诱导小鼠睾丸中细胞色素c(Cyt c)和caspase-3表达的变化,阐明二者对低剂量电离辐射诱导小鼠睾丸细胞凋亡的作用.方法:实验小鼠分为不同剂量(0、0.050、0.075、0.100和0.200 Gy)组与不同时程(0、6、12和24 h)组.采用实时PCR和Western blotting分别检测不同剂量X射线照射后不同时间小鼠睾丸组织中细胞色素c(Cyt c)和caspase-3 mRNA和蛋白表达的变化.结果:实时PCR结果显示,不同剂量X射线照射后12 h,Cyt c和caspase-3 mRNA表达随剂量增加而增加,Cyt c mRNA在0.100 Gy照射时表达最多,而caspase-3则在0.075 Gy照射时表达最多;在0.075 Gy照射时二者蛋白表达最多.0.075 Gy照射后Cyt c和caspase-3 mRNA表达随着时间延长表达增多,24 h时达到最高;二者蛋白表达在12 h时最高.结论:低剂量电离辐射能够诱导小鼠睾丸生精细胞中Cyt c和caspase-3 mRNA和蛋白表达的增加,并且具有剂量和时程规律性.  相似文献   

5.
目的:初步评价外放疗联合碘-125(125I)粒子植入治疗头颈癌患者的局部控制率和放射性损伤的有关结果.方法:选择2008年2月至2010年7月在北京大学口腔医院口腔颌面外科就诊的头颈痛患者10例,其中鳞状细胞癌8例,低分化腺癌2例,均因全身疾病或局部晚期而不能手术治疗.所有患者均先接受常规分割外放疗,然后再行125I粒子植入增量放疗.外放疗总照射剂量(total dose,Dt)为50 Gy(鳞癌)或70 Gy(低分化腺癌);125I粒子植入治疗的匹配周缘剂量(matched peripheral dose,MPD)为60 Gy(TNM分期为Ⅰ~Ⅱ)或80 Gy(TNM分期为Ⅲ~Ⅳ).125I粒子活度为25.9~29.6 MBq/个.对患者进行随访,分析急性放射性损伤、晚期放射性损伤、局部控制和生存情况.结果:平均随访12个月(2~28个月),有1例出现软组织坏死,1例出现吞咽困难和局部大出血,余末见其他严重副作用.所有病灶均在6个月内完全消退,1例出现颈淋巴结转移,1例出现远处转移,余未见复发和转移.10例患者中有7例存活.结论:外放疗联合125I粒子植入是治疗不能根治手术头颈癌患者的一种安全、有效的选择方法.  相似文献   

6.
目的:观察微波辐射对人神经母细胞瘤SH-SY5Y细胞凋亡的影响,并探讨其机制.方法:采用10、30和50 mW·cm-2辐射强度的微波辐射SH-SY5Y细胞5 min,以假辐射组(0 mW·cm-2)为对照,光镜下观察细胞形态变化;荧光显微镜下观察DAPI染色细胞核的形态;CTAB法提取细胞基因组DNA,电泳观察DNA ladder;台盼蓝拒染法检测细胞存活率;AnnexinV-FITC和PI双染色,流式细胞仪检测细胞凋亡率;MTT法检测细胞相对活性;蛋白质印迹检测细胞凋亡相关蛋白的表达.结果:微波辐射后SH-SY5Y细胞形态即刻改变,胞核、胞质结构欠清,细胞皱缩甚至脱壁;细胞核内的染色质出现不规则凝集,碎裂成2~5个微核;细胞DNA出现明显的梯状条带;细胞存活率随微波辐射强度增大逐渐降低,10 mW·cm-2辐射组与假辐射组比较,细胞存活率差异无统计学意义(P>0.05),但30、50 mW·cm-2辐射组细胞存活率明显低于假辐射组(P<0.05);微波辐射后6 h的细胞凋亡率随辐射强度的增加逐渐升高,各辐射组细胞凋亡率均明显高于假辐射组(P<0.05);微波辐射后24和48 h,细胞相对活力随辐射强度的增加明显降低,各辐射组的细胞相对活力均明显低于假辐射组(P<0.05).微波辐射后,细胞凋亡相关蛋白Bcl-2、survivin表达水平逐渐下降,Bax、caspase-3 和caspase-7表达水平逐渐升高,caspase-8和-9表达水平无明显变化.结论:微波辐射可诱导SH-SY5Y细胞凋亡,其作用机制可能与survivin、Bcl-2蛋白表达水平下调、Bax蛋白表达水平上调及caspase-3和caspase-7的作用有关,而与caspase-8和caspase-9介导的caspase-3活化这一作用无密切关系.  相似文献   

7.
目的:观察taurolidine联合X射线照射对小鼠恶性黑色素瘤(B16-4A5和B16-F10)细胞周期进程的影响,探讨其诱导肿瘤细胞凋亡的发生机制.方法:选择B16-4A5和B16-F10细胞系按给药浓度随机分为4组,taurolidine剂量分别为0、25、50和100 μmol·L-1,同时进行1、2和4 Gy X射线照射,采用流式细胞术检测细胞凋亡率和细胞周期,Western blotting分析cyclin B、cdc2和caspase-3的表达.结果:与25 μmol·L-1 taurolidine组比较,50和100 μmol·L-1 taurolidine组诱导B16-4A5和B16-F10细胞发生G0/G1期阻滞,细胞数分别升高54.9%、73.7%和36.8%、55.5%(P<0.05); 50 μmol·L-1 taurolidine联合2和4 Gy X射线照射组,细胞G2/M期阻滞消除,细胞数分别降低52.1%、44.2%和59.3%、52.7%(P<0.05).与对照组、单纯taurolidine组及单纯照射组比较,联合4 Gy X射线照射组cyclin B和cdc2的表达降低,caspase-3的表达升高(P<0.05).结论:taurolidine联合X射线照射可去除G2/M期阻滞,可选择地抑制肿瘤细胞cyclin B和cdc2的表达、增强caspase-3的表达,共同诱导细胞凋亡.  相似文献   

8.
目的:回顾分析单独应用125Ⅰ放射性粒子组织间植入近距离放疗治疗口腔颌面-头颈部腺源性恶性肿瘤的近期疗效.方法:2001年至2008年北京大学口腔医院颌面外科头颈部腺源性恶性肿瘤患者43人,因全身或局部因素不能进行手术切除,肿瘤部位包括腮腺、舌、上颌、颌下、咽旁、颅底颞下凹和口底.肿瘤直径为2~8 cm.本组患者均采用了单独125Ⅰ放射性粒子组织间植入治疗,粒子活度2.59×107~2.96×107 Bq(0.7~0.8 mCi),周缘匹配剂量为120~160 Gy.术后复查随访,统计有效率、局部控制率和生存率,以及副反应等情况.结果:治疗使29人获得了肿瘤完全消退(完全缓解complete remission,CR),7人消退大于50%(部分缓解partial remission,PR),4人消退小于50%,2人无效,有效率CR+PR为83.7%.术后随访时间为8~48个月,平均21个月,失访1人,局部控制率为79%,总生存率为76.7%,最长无瘤生存已达48个月,未发现严重放疗副反应.结论:对于手术禁忌的患者或无法切除的腺源性肿瘤,放射性粒子组织间植入近距离放疗可以获得较好的近期疗效.  相似文献   

9.
目的:检测人信号转导及转录活化因子3(STAT3)蛋白在乳腺癌组织中的表达,探讨其与乳腺癌患者临床病理参数及预后的关系.方法:应用免疫组织化学SP法检测67例乳腺癌及其配对正常乳腺组织中STAT3蛋白的表达水平,分析具有不同临床病理参数患者间STAT3的表达情况.结果:STAT3蛋白在乳腺癌组织的表达水平明显高于正常乳腺组织(P<0.001),STAT3表达水平与乳腺癌患者年龄、肿瘤大小和组织学类型无关联性(P>0.05),与乳腺癌临床分期、淋巴结转移情况及患者生存时间有关联(P<0.05).临床分期越高的乳腺癌组织中STAT3的表达阳性率越高(P<0.05);有淋巴结转移者STAT3阳性表达率明显高于无淋巴结转移者(P<0.05);STAT3阳性表达的患者生存时间[(51.1±4.4)月]明显短于阴性表达的患者[(86.0±4.9)月](P<0.05).结论:STAT3蛋白的过表达可能在乳腺癌的发生发展过程中发挥了促进作用,并且是乳腺癌患者预后不良的一个重要指标.  相似文献   

10.
目的:携带癌胚抗原(carcinocmbryonic antigen,CEA)基因的重组人腺相关病毒(reconstructive human adeno-association virus,rh-AAV)感染树突状细胞(dendritic cell,DC)诱导获得抗原特异性细胞毒性T淋巴细胞(cytotoxic lymphocyte,CTL),体外检测其对CD44+CD24-/low乳腺癌干细胞的杀伤效果.方法:分离供者外周血单个核细胞,以细胞因子白介素-4(interleukin-4,IL-4)、粒细胞-巨噬细胞克隆刺激因子(granulocyte-macrophage colony-stimulating factor,GM-CSF)和肿瘤坏死因子α(tumor necrosis factor-alpha,TNF-α)诱导培养获得DC,细胞因子白介素-2(interleukin-2,IL-2),刺激培养获得T淋巴细胞.含CEA基因的rh-AAV感染培养DC,诱导成熟后将DC和T细胞混合培养获得CTL细胞.流式分选MCF-7和MA-MDB-231细胞系中CD44+CD24-/low乳腺癌干细胞,MTT法检测CTL细胞对CD44+CD24-/low乳腺癌干细胞的杀伤效果.结果:MCF-7和MDA-MB-231中CD44+/CD24-/low群比例分别为5.1%和76.3%.CEA基因转染DC诱导的CTL细胞对表达CEA抗原的MCF-7杀伤率为46.5%±15.0%,与未转染组相比,差异有统计学意义(P=0.009);对MCF-7细胞中分选的CD44+CD24-/low乳腺癌干细胞的杀伤率为44.7%±28.2%,明显高于未转染组.对非乳腺癌干细胞杀伤率为50.6%±22.2%,与未转染组相比,差异有统计学意义(P=0.05).在不表达CEA基因的MDA-MB-231乳腺癌细胞,CEA转染诱导的CTL细胞对未分选细胞、分选的CD44+/CD24-/low亚群和非干细胞亚群的杀伤率与未转染的对照组相比,差异均无统计学意义(P>0.05).结论:携带CEA基因rh-AAV转染DC诱导产生的抗原特异性CTL细胞可杀伤表达CEA的乳腺癌细胞,对CD44+CD24-/low乳腺癌干细胞也具有一定的杀伤活性,提示免疫治疗可能是治疗乳腺癌干细胞潜在有效的手段.  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

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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   

18.
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   

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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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