首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到18条相似文献,搜索用时 151 毫秒
1.
目的 探究敲低microRNA(miR)-19a和miR-19b表达对人脑胶质瘤细胞系SNB19细胞生物学特征的影响.方法 常规培养SNB19细胞,脂质体介导miR-19a、miR-19b抑制物转染SNB19细胞,同时设未转染组(对照组)、无义序列转染组和miR-19a+miR-19b抑制物转染组.应用RT-PCR检测转染后细胞miR-19a、miR-19b的表达,MTT、流式细胞术分别检测转染后细胞增殖能力和细胞周期的变化,Transwell实验检测转染后细胞的侵袭能力.结果 与对照组和无义序列转染组比较,抑制物转染组细胞miR-19a和miR-19b的表达、增殖和侵袭能力均降低,差异有统计学意义(P<0.05),而且miR-19a+miR-19b抑制物转染组细胞miR-19a和miR-19b的表达、转染后2、3、4、5 d细胞的增殖能力、侵袭能力均低于miR-19a、miR-19b抑制物转染组,差异有统计学意义(P<0.05);抑制物转染组较对照组和无义序列转染组细胞周期延迟,且miR-19a+miR-19b抑制物转染组较miR-19a、miR-19b抑制物单独转染组细胞延迟更为明显.结论 miR-19a和miR-19b可能是癌微RNA,有望作为人脑胶质瘤基因治疗的侯选靶点.
Abstract:
objective To investigate the effects of knocking down of miR-19a and miR-19b on the biological characteristics of SNB19 glioblastoma cells. Methods Oligonucleotides inhibitor of miR-19a and miR-19b (miR-19a inhibitor or miR-19b inhibitor) mediated by lipofectamine2000 were transfected to SNB19 cells to knock down miR-19a and miR-19b; control group (without transfection),group D (performing transfection with nonsense sequence) and group E (performing transfection with both miR-19a inhibitor and miR-19b inhibitor) were established. Real time PCR was conducted to detect the expressions ofmiR-19a and miR-19b in these groups after the transfection. The cell proliferation rate and cell cycle kinetics were detected by 3-(4, 5-Dime- -thylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and flow cytometry, respectively; the cell invasive ability was evaluated by Transwell assay.Results As compared with those in control group and group D, the expressions of miR-19a and miR-19b, proliferation activity and invasive ability of cells in the miR-19a/19b inhibitor transfected cells (group A/B) were significantly reduced (P<0.05). The expressions of miR-19a and miR-19b and the proliferation activity and invasive ability of cells 2, 3, 4 and 5 d after the transfection in group E were significantly reduced as compared with those in group A/B (P<0.05). Delayed cell cycle in group A/B and group E was noted as compared with that in control group and group D; and group E enjoyed more obviously delayed eell cycle than group A/B (P<0.05). Conclusion MiR-19a and miR-19b might be oncomiRs, and may be candidate target miRNAs for gene therapy of glioma.  相似文献   

2.
反义miR-21抑制异种移植U87人脑胶质瘤生长的体内研究   总被引:4,自引:1,他引:4  
目的 探讨敲低miR-21表达抑制裸鼠皮下荷U87人脑胶质瘤生长的疗效和机制.方法 原位注射miR-21反义寡聚核苷酸(AS-miR-21)治疗裸鼠皮下荷U87人脑胶质瘤.定时测量肿瘤大小评估原位注射AS-miR-21的治疗效果.使用RT-PCR和原位杂交方法 鉴定治疗后miR-21表达水平,采用HE染色和免疫组织化学染色(增殖细胞核抗原、细胞周期抑制因子-21、基质金属蛋白酶-9和隔蛋白-7)评价治疗后肿瘤生物学性状的变化,TUNEL法检测肿瘤细胞凋亡. 结果 肿瘤生长曲线显示AS-miR-21治疗组肿瘤生长速度及体积明显小于对照组与无义序列治疗组,差异有统计学意义(F=6.056,P=0.007);RT-PCR检测显示AS-miR-21治疗组miR-21表达下调为对照组的(0.031±0.008)%;原位杂交显示AS-miR-21治疗组miR-21表达水平较对照组与无义序列治疗组下调:组织病理学检测表明AS-miR-21治疗后肿瘤恶性度降低;TUNEL法检测可见AS-miR-21治疗组细胞凋亡数明显高于对照组与无义序列治疗组,差异有统计学意义(F=141.021,P=0.000). 结论 以miR-21作为靶点治疗异种移植U87人脑胶质瘤效果令人满意,miR-21可作为人脑胶质瘤基因治疗的侯选靶点.  相似文献   

3.
目的 探讨胶质瘤细胞LN229中RECK作为miR-21的调控靶点,在胶质瘤侵袭性生长中的作用.方法 将反义miR-21(AS-miR-21)寡核苷酸转染至人脑胶质瘤细胞LN229中.Real-time PCR检测LN229细胞中miR-21的表达量.荧光素酶实验检测miR-21对RECK的调控关系.Transwell实验评价LN229细胞侵袭能力的变化,应用Western blot检测细胞内MMP2/9和RECK蛋白水平的变化,ELISA实验检测培养基中活性MMP2/9的表达量,动物实验评价体内条件下肿瘤侵袭性的变化.结果 Real-time PCR显示转染组中miR-21的表达量与对照组相比下调60%.荧光素酶实验证明RECK是miR-21的靶点.Transwell实验证实胶质瘤细胞侵袭能力下降,Western blot和ELISA实验证实MMP2/9表达降低,动物实验及免疫荧光反映肿瘤侵袭性生长受抑制.结论 反义miR-21通过上调RECK的表达而抑制恶性胶质瘤细胞的侵袭性生长.
Abstract:
Objective To investigate the regulation of miR - 21 on invasion growth of human glioma cells by RECK.Method The human glioma LN229 cells were transfected with AS - miR - 21 or scrambled sequences by Lipofectamine2000.Real time PCR was conducted to detect the expression of miR-21.Luciferase experiment was performed to detect the relationship between miR-21 and RECK.The expression of RECK was evaluated by Western blot.The invasion ability was evaluated by transwell assay and subcutaneous models.Western Blot, ELISA and immunofluorescence were used to estimate the changes of MMP2/9.Results The expression of miR - 21 in LN229 cells decreased after transfection with AS-miR-21. It was proved that RECK was a direct target of miR -21 by luciferase experiment.Meanwhile, the high expression of RECK protein in AS - miR -21 group conformed its important function in this mechanism.Transwell assay demonstrated decreased invasion capability of LN229 cell lines transfected with AS- miR- 21.Western blot, ELISA, and immunofluorescence demonstrated the levels of MMP2/9 were down -regulated in AS -miR -21 group compared with control and scrambled group.Conclusions AS - miR -21 could depress the invasion of glioma cells owing to up - regulating the level of RECK which could inhibit MMP2/9 activities both in vitro and vivo.  相似文献   

4.
Notch受体阻断剂MW167抑制U87胶质瘤细胞增殖的作用研究   总被引:1,自引:0,他引:1  
目的 探讨Notch受体阻断剂MW167对胶质瘤细胞系U87增殖及凋亡的影响.方法 采用四甲基偶氮唑蓝(MTT)法检测MW167对体外培养的胶质瘤细胞系U87的增殖抑制作用.流式细胞仪AnnexinV-FITC和PI双染检测凋亡率.结果 MTT法检测显示MW167能明显抑制U87细胞的增殖并呈剂量依赖关系:流式细胞仪检测显示MW167可诱导U87胶质瘤细胞发生凋亡并呈剂量依赖关系.结论 MW167明显抑制U87胶质瘤细胞的增殖并诱导其发生凋亡,提示Noah受体阻断剂MW167对人脑胶质瘤的治疗具有潜在的临床应用价值.  相似文献   

5.
目的 研究磷酸化STAT3抑制剂Cucurbitacin Ⅰ阻断STAT3信号转导通路对人脑胶质瘤细胞系A172增殖和凋亡的影响并探讨机制.方法 使用Cucurbitacin Ⅰ处理人脑胶质瘤细胞系A172,CCK-8方法检测细胞增殖状态,流式细胞仪检测细胞凋亡,Western blot检测STAT3磷酸化水平,RT-PCR检测STAT3下游基因C-myc、Survivin和Mcl-1的mRNA水平的改变.结果 Cucurbitacin Ⅰ作用于A172后,细胞增殖速度明显下降(P<0.05);细胞凋亡比率显著升高;Western blot结果显示A172细胞中磷酸化STAT3(p705-STAT3)蛋白水平明显降低;C-myc、Survivin和Mcl-1在mRNA水平明显下降(P<0.05).结论 阻断STAT3信号转导通路可抑制脑胶质瘤细胞增殖,促进其凋亡;靶向STAT3信号转导通路的治疗策略可以作为胶质瘤治疗的一种新方法.  相似文献   

6.
目的 探讨miR -21过表达在替莫唑胺诱导胶质瘤U87细胞凋亡中的作用及其机制.方法 miR - 21过表达载体转染U87细胞,Hoechst 33258染色和流式细胞分析凋亡,Westem blot验证Bax和Bcl -2表达及检测Caspase -3活性.结果 替莫唑胺可显著诱导U87细胞凋亡,上调Bax 表达、下调Bcl-2表达及增加Caspase -3活性.U87细胞预转染miR -21过表达载体后,替莫唑胺的这种效应可部分被抑制.结论 miR -21过表达可通过下调Bax/Bcl -2比率及Caspase -3活性部分抑制替莫唑胺诱导的U87细胞凋亡,提示胶质瘤中miR -21过表达可能是胶质瘤对替莫唑胺耐药的一大新的因素.  相似文献   

7.
反义miR-21抑制U251人脑胶质瘤细胞株增殖的体外研究   总被引:1,自引:1,他引:1  
目的 探讨敲低miR-21表达抑制U251人脑胶质瘤细胞株增殖能力的效果和机制.方法 脂质体介导转染反义寡聚核苷酸(AS-miR-21)下调U251人脑胶质瘤细胞株miR-21的表达.使用实时定量PCR和原位杂交法鉴定转染后U251细胞miB-21表达水平下调;MTY法评价AS-miR-21抑制U251细胞生长效果;流式细胞术检测转染后U251细胞周期分布和凋亡;采用细胞免疫荧光技术(PCNA、CyelinD1、Bcl-2、PTEN和Septin-7)评价转染后U251细胞肿瘤生物学性状改变.结果 MTT结果显示AS-miR-21转染组肿瘤细胞生长速度小于对照组与无义寡核苷酸(F=78.926,P=0.000)组;实时定量PCR法:AS-miR-21转染组miR-21表达下调为对照组0.042±0.012;LNA-miR-21原位杂交显示AS-miR-21转染组miR-21表达水平较对照组与无义寡核苷酸组下调;流式细胞术检测可见AS-miR-21转染组细胞周期存在G0/G1期阻滞(X2=14.160,P=0.007)且凋亡比例高于对照组与无义寡核苷酸组(F=23341.25,P=0.000);细胞免疫荧光法表明AS-miR-21治疗后U251细胞PCNA、CyclinD1、Bcl-2表达下调,PrEN、Septin-7表达上调.结论 以miR-21作为靶点抑制U251人脑胶质瘤细胞株生长结果肯定,miR-21可以作为人脑胶质瘤基因治疗的侯选靶点.  相似文献   

8.
目的 探讨下调miR-221对U87胶质瘤细胞生长的影响及可能的作用机制.方法 构建靶向miR-221的siRNA慢病毒表达载体并感染U87胶质瘤细胞,应用原位杂交、定量PCR和Western blot法检测干扰后细胞内miR-221及p27蛋白表达变化,MTT法检测细胞增殖,流式细胞仪检测细胞凋亡及周期变化,Transwell法检测细胞侵袭力改变.结果 成功构建了靶向miR221的siRNA慢病毒表达载体,该载体能有效抑制内源性miR-221的表达,同时上调p27蛋白的表达,同时抑制细胞生长,诱导凋亡,降低细胞的侵袭力.结论 成功构建靶向miR-221的RNAi慢病毒表达载体,该载体能够有效抑制miR-221的表达并抑制U87胶质瘤细胞的生长,为以miR-221为靶点的胶质瘤基因治疗的后续研究奠定基础.  相似文献   

9.
目的 探究敲低IKKε表达对人胶质瘤细胞系U251生物学特征的影响. 方法 采用脂质体介导的IKKε小干扰RNA(IKKε siRNA)转染U251细胞,同时设转染无义序列组和对照组,RT-PCR鉴定转染后IKKε mRNA的表达;MTT法检测转染后细胞的增殖能力;流式细胞术检测细胞周期分布的改变;Transwell实验检测细胞侵袭能力的变化;Western blotting法检测核增殖抗原(PCNA)、细胞周期素D1 (Cyclin D1)、基质金属蛋白酶-9(MMP9)和NF-κB P65的表达. 结果 与对照组和无义序列组比较,转染IKKε siRNA组细胞IKKε mRNA的表达和细胞增殖率降低,G0/G1期细胞比例增高,穿膜细胞数明显减少,差异均有统计学意义(P<0.05).Western blotting检测结果显示IKKε siRNA组细胞PCNA、MMP9、Cyclin D1的表达较对照组和无义序列组明显下调,而且NF-κB组分P65从胞浆向胞核的转座减少. 结论 IKKε在胶质瘤细胞增殖和侵袭过程中发挥重要作用,有望成为人脑胶质瘤基因治疗的侯选靶点.  相似文献   

10.
反义miRNA-221/222上调p27kip1抑制胶质瘤细胞生长的体外研究   总被引:1,自引:3,他引:1  
目的 探讨敲低miRNA-221/222表达上调p27kip1抑制U251人脑胶质瘤细胞株生长的效果及机制.方法 脂质体共转染反义miRNA-221/222下调U251人脑胶质瘤细胞株miRNA-221、miRNA-222的表达.使用Northern blot方法 鉴定转染后U251细胞miRNA-221、miRNA-222表达水平下调;MTT法评价反义miRNA-221/222抑制U251细胞生长效果;流式细胞术检测转染后U251细胞周期分布;Western blot分析p27kip1蛋白的表达变化.结果 Northern blot显示反义miRNA-221/222共转染组使miRNA-221、miRNA-222的表达水平明显下降.反义miRNA-221转染组仅使miRNA-221的表达水平明显下降,反义miRNA-222转染组仅使miRNA-222的表达水平明显下降.转染无意序列组及对照组的miRNA-221、miRNA-222表达水平没有改变.MTT结果 显示反义miRNA-221/222共转染组肿瘤细胞生长速度小于对照组、转染无意序列组、转染反义miRNA-221组、转染反义miRNA-222组.流式细胞术检测可见反义miRNA-221/222共转染组细胞周期存在G0/G1期阻滞且明显高于其他各组.Western blot显示反义miRNA-221/222共转染组的p27kip1蛋白表达明显上调.结论 反义miRNA-221/222通过上调p27kip1蛋白表达来抑制胶质瘤细胞U251的生长.  相似文献   

11.
目的探讨胶质瘤病人血清外泌体miRNA-30a-5p的表达水平,及其在胶质瘤诊断及预后评估中的价值。方法选取2014年1月至2015年12月收治的胶质瘤60例为研究对象,另选取健康体检者40例为对照。RT-PCR检测血清外泌体miRNA-30a-5p表达水平。用受试者工作特性(ROC)曲线分析miRNA-30a-5p诊断胶质瘤的价值。用Kaplan-Meier法绘制生存曲线,采用log-rank检验;多因素Cox比例风险回归模型分析预后危险因素。结果胶质瘤病人血清外泌体miRNA-30a-5p表达水平明显高于健康人(P<0.001)。ROC曲线分析显示,血清外泌体miRNA-30a-5p诊断胶质瘤的曲线下面积为0.901(95%CI0.812~0.986),最佳截断值为0.601,此时miRNA-30a-5p诊断胶质瘤的灵敏度和特异度分别为78.05%和93.55%。术后60例均得到有效随访,随访时间平均(28.39±3.25)个月。Kaplan-Meier分析结果显示,血清外泌体miRNA-30a-5p低表达病人总体生存时间高于高表达病人(P<0.001)。多因素Cox比例回归风险模型分析结果显示血清外泌体miRNA-30a-5p高表达是胶质瘤病人不良预后的独立影响因素(P<0.05)。结论血清外泌体miRNA-30a-5p对胶质瘤的诊断和预后评价均有一定价值。  相似文献   

12.
Ischemia-induced angiogenesis contributes to various neuronal and retinal diseases, and often results in neurodegeneration and visual impairment. Current treatments involve the use of anti-VEGF agents but are not successful in all cases. In this study we determined that miR-30a-5p is another important mediator of retinal angiogenesis. Using a rodent model of ischemic retinopathy, we show that inhibiting miR-30a-5p reduces neovascularization and promotes tissue repair, through modulation of microglial and endothelial cell cross-talk. miR-30a-5p inhibition results in increased expression of the death receptor Fas and CCL2, to decrease endothelial cell survival and promote microglial migration and phagocytic function in focal regions of ischemic injury. Our data suggest that miR-30a-5p inhibition accelerates tissue repair by enhancing FasL–Fas crosstalk between microglia and endothelial cells, to promote endothelial cell apoptosis and removal of dead endothelial cells. Finally, we found that miR-30a levels were increased in the vitreous of patients with proliferative diabetic retinopathy. Our study identifies a role for miR-30a in the pathogenesis of neovascular retinal disease by modulating microglial and endothelial cell function, and suggests it may be a therapeutic target to treat ischemia-mediated conditions.  相似文献   

13.
目的 探讨敲低miR-221/222表达上调PUMA对U251人脑胶质母细胞瘤凋亡的影响及其机制. 方法 5周龄BALB/c裸鼠左侧鼷部皮下接种1 mm3移植胶质瘤瘤块建立裸鼠移植瘤模型,1周后接受治疗(转染无义序列组、反义miR-221/222共转染组分别瘤内注射无义对照序列、反义miR-221/222寡核苷酸,对照组注射等量溶剂,每组8只).治疗开始至28 d观察肿瘤的生长情况,观察期结束时取肿瘤组织HE染色检测病理学改变;荧光原位杂交(FISH)、实时定量PCR检测肿瘤组织miR-221、miR-222的表达;TUNEL染色检测肿瘤细胞凋亡,免疫组化染色、Western blotting检测肿瘤组织凋亡相关蛋白PUMA、bax和bcl-2、p53的表达. 结果 治疗后6~28 d反义miR-221/222共转染组移植瘤的体积明显低于对照组和转染无义序列组,差异有统计学意义(P<0.05);与转染无义序列组及对照组比较,反义miR-221/222共转染组肿瘤组织miR-221、miR-222 mRNA的表达水平下降;HE染色显示反义miR-221/222共转染组肿瘤组织异型性减低,新生血管数减少;与对照组和转染无义序列组比较,反义miR-221/222共转染组肿瘤组织的凋亡指数较高,差异有统计学意义(P<0.05);免疫组化染色检测显示与对照组和转染无义序列组比较,反义miR-221/222共转染组PUMA、bax表达阳性率较高,bcl-2表达阳性率较低,差异有统计学意义(P<0.05); Western blotting检测显示与对照组和转染无义序列组比较,反义miR-221/222共转染组肿瘤组织PUMA和bax蛋白表达升高,bcl-2表达下降,而p53表达无明显变化. 结论 反义miR-221/222治疗可通过上调PUMA蛋白表达来诱导U251胶质瘤细胞凋亡.  相似文献   

14.
目的探讨miR-1224-5p在胶质瘤中的表达及其对人脑胶质瘤细胞增殖的影响。方法分析中国脑胶质瘤基因组计划(CGGA)数据库中miR-1224-5p在不同级别的胶质瘤组织中的表达数据,并采用原位杂交技术进行组织验证,运用CGGA数据分析miR-1224-5p的表达水平与胶质母细胞瘤患者临床预后的相关性。采用miR-1229-5p寡聚核苷酸转染胶质瘤U251及U87细胞,通过CCK8实验观察上调miR-1224-5p表达后对胶质瘤细胞增殖的影响。结果 miR-1224-5p在人脑胶质瘤组织中的表达随着病理分级的升高而降低。胶质母细胞瘤患者中低表达miR-1224-5p提示预后不良。上调miR-1224-5p表达可以抑制胶质瘤细胞的增殖。结论 miR-1224-5p与胶质瘤的级别和临床预后相关,miR-1224-5p可以抑制胶质瘤细胞的增殖能力。  相似文献   

15.
目的 探讨微小RNA-370-3p(miR-370-3p)对人脑胶质瘤细胞系U87-MG增殖能力的影响及其机制。方法 将常规培养的U87-MG细胞分为空白组、无义序列转染组和模拟物转染组,后两组分别转染miRNA无义序列及miR-370-3p模拟物,qRT-PCR法检测其转染效率,免疫印迹法检测转染细胞叉头框蛋白M1(FoxM1)的表达;采用EdU法评估细胞的增殖能力,采用平板克隆形成实验检测细胞的增殖能力。结果 与空白组和无义序列转染组比较,模拟物转染组细胞miR-370-3p表达显著增加(P<0.05),而FoxM1的蛋白表达显著减少(P<0.05);而且模拟物转染组U87-MG细胞增殖能力及克隆形成率均明显减少(P<0.05)。结论 miR-370-3p能够抑制U87-MG细胞的增殖能力,可能与减少FoxM1的表达有关。  相似文献   

16.
Glia-mediated neuroinflammation plays an important role in the pathogenesis of neuropathic pain. Our recent study demonstrated that TNF receptor associated factor-6 (TRAF6) is expressed in spinal astrocytes and contributes to the maintenance of spinal nerve ligation (SNL)-induced neuropathic pain. MicroRNA (miR)-146a is a key regulator of the innate immune response and was shown to target TRAF6 and reduce inflammation. In this study, we found that in cultured astrocytes, TNF-α, IL-1β, or lipopolysaccharide (LPS) induced rapid TRAF6 upregulation and delayed miR-146a-5p upregulation. In addition, miR-146a-5p mimic blocked LPS-induced TRAF6 upregulation, as well as LPS-induced c-Jun N-terminal kinase (JNK) activation and chemokine CCL2 expression in astrocytes. Notably, LPS incubation with astrocytes enhanced the DNA binding activity of AP-1 to the promoters of mir-146a and ccl2. TRAF6 siRNA or JNK inhibitor SP600125 significantly reduced LPS-induced miR-146a-5p increase in astrocytes. In vivo, intrathecal injection of TNF-α or LPS increased spinal TRAF6 expression. Pretreatment with miR-146a-5p mimic alleviated TNF-α- or LPS-induced mechanical allodynia and reduced TRAF6 expression. Finally, SNL induced miR-146a-5p upregulation in the spinal cord at 10 and 21 days. Intrathecal injection of miR-146a-5p mimic attenuated SNL-induced mechanical allodynia and decreased spinal TRAF6 expression. Taken together, the results suggest that (1) miR-146a-5p attenuates neuropathic pain partly through inhibition of TRAF6 and its downstream JNK/CCL2 signaling, (2) miR-146a-5p is increased by the activation of TRAF6/JNK pathway. Hence, miR-146a-5p may be a novel treatment for chronic neuropathic pain.  相似文献   

17.
目的 探讨生长激素腺瘤血清Micr0-RNA(miRNA)的表达情况,及miR-423-5p对生长激素腺瘤增殖的影响.方法 各检测6例生长激素腺瘤病人和正常人血清外泌体miRNA的表达情况,对比两者之间的差异.结果 外泌体miRNA表达谱显示:生长激素腺瘤病人和正常人血清之间有169个差异表达miRNA(P<0.05,...  相似文献   

18.
目的探讨p53基因和PTEN基因在脑胶质瘤细胞系U251发生发展过程中的作用机制。方法用不同MOI的p53腺病毒表达载体pAdCMV-p53及空载体pAdCMV-lacZ分别感染表达野生型PTEN基因和突变型PTEN基因的细胞系,RT-PCR及Westernblot方法检测转染效率;并通过MTT检测生长抑制率、流式细胞仪检测细胞周期及TUNEL检测分析细胞凋亡等指标观察p53基因及PTEN基因对U251细胞生长的影响。结果MOI为100时,p53基因可引起U251细胞G0G1期阻滞、诱导细胞凋亡,生长抑制;MOI为50时,U251-p53 PTEN生长抑制率明显高于U251-p53,并能出现细胞凋亡,而U251-p53仅出现少量细胞凋亡。结论p53基因可以通过细胞周期G0G1期阻滞及诱导细胞凋亡抑制胶质瘤细胞系U251的生长;PTEN基因可以促进p53基因对胶质瘤细胞系U251的生长抑制作用,并能增加U251细胞对p53基因诱导凋亡的敏感性。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号