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1.
目的:研究坏死性凋亡是否介导高糖(HG)诱导的人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs)损伤。方法:CCK-8法检测细胞存活率;Western blot法测定受体相互作用蛋白3(RIP3)、cleaved caspase-3的蛋白水平;罗丹明123染色荧光显微镜照相法检测线粒体膜电位(mitochondrial membrane potential,MMP);双氯荧光素(DCFH-DA)染色荧光显微镜照相法测定胞内活性氧簇(reactive oxygen species,ROS)的水平。结果:应用不同浓度葡萄糖(10、20和40 mmol/L)处理HUVECs 24 h,RIP3的蛋白水平随葡萄糖剂量增加而升高,40 mmol/L时达高峰;应用40 mmol/L葡萄糖处理HUVECs 3 h、6 h、9 h、12 h和24 h能上调RIP3的蛋白水平,于9 h达最高峰;应用20μmol/L凋亡蛋白酶抑制剂Z-VAD-FMK预处理HUVECs 30 min促进RIP3表达;应用100μmol/L坏死性凋亡抑制剂necrostatin-1预处理HUVECs 1 h能抑制HG诱导HUVECs的细胞存活率降低,ROS过度生成及MMP丢失,但能升高cleaved caspase-3的蛋白水平。结论:坏死性凋亡介导高糖引起的人脐静脉内皮细胞损伤,但与内皮细胞凋亡存在负相关。  相似文献   

2.
AIM: To investigate the effects of human induced pluripotent stem cell-derived exosomes( hi PSC-exo) on cell viability,capillarylike structure formation,and senescence in endothelial cells exposed to high glucose. METHODS: Exosomes were isolated from the conditional medium of hi PSCs and confirmed by transmission electron microscopy,nanoparticle tracking analysis,and Western blot analysis using Alix and CD63 as markers. hi PSC-exo were labeled with PKH26 for tracking. Cultured HUVECs were treated with high glucose(33 mmol / L) with or without hi PSC-exo(20 mg / L) for 48 h,and cell viability,capillary tube formation,and senescence were assessed. RESULTS: hi PSC-exo showed a typical cup shape and could be taken up by human umbilical vascular endothelial cells(HUVECs) in a concentration-dependent manner. When exposed to high glucose,viability and tube formation in HUVECs was significantly reduced,whereas the proportion of senescent cells was higher compared to that in control HUVECs( P 0. 01). Furthermore,hi PSC-exo restored cell viability and capillary-like structure formation,and reduced senescence in HUVECs exposed to high glucose(P 0. 01). However,hi PSC-exo had minimal effects on normal HUVECs. Therefore,stem cell-derived exosomes can promote cell proliferation, enhance capillary-like structure formation, and reduce senescence in endothelial cells exposed to high glucose.CONCLUSION: Our study highlights the role of exosomes derived from hi PSC and may provide a new strategy for maintaining vascular health,preventing vascular aging,and avoiding pathological vascular remodeling that occurs in many diseases.  相似文献   

3.
目的:研究抗衰老Klotho蛋白对高糖作用下血管内皮细胞的保护作用及其作用机制。方法:体外培养人脐静脉血管内皮细胞(HUVECs),设置PBS对照组、5.5 mmol/L葡萄糖组、33.3 mmol/L葡萄糖组、0.1μmol/L Klotho+33.3 mmol/L葡萄糖组、1μmol/L Klotho+33.3 mmol/L葡萄糖组和10μmol/L Klotho+33.3 mmol/L葡萄糖组。使用MTT法检测各组细胞活力;同时检测各组细胞培养上清中丙二醛(MDA)的含量以及乳酸脱氢酶(LDH)、超氧化物歧化酶(SOD)和还原型谷胱甘肽(GSH)的活性;流式细胞术检测各组细胞中活性氧(ROS)含量变化;ELISA检测各组细胞培养液中一氧化氮(NO)、内皮素1(ET-1)和细胞间黏附分子1(ICAM-1)的浓度变化;Western blot法检测各组细胞中核因子κB(NF-κB)蛋白的表达。结果:与PBS对照组相比,33.3 mmol/L葡萄糖能够显著降低HUVECs的细胞活力,增加细胞中ROS的含量,增加细胞培养上清中LDH活性和MDA含量,降低SOD和GSH的活性,同时降低NO分泌,诱导ET-1、ICAM-1分泌及细胞中NF-κB蛋白的表达(P0.05)。不同浓度Klotho蛋白和33.3 mmol/L高糖同时作用HUVECs时,细胞活力逐渐上升,ROS和MDA含量以及LDH活性逐渐下降,SOD和GSH活性则逐渐上升,同时NO分泌增加,ET-1、ICAM-1分泌及NF-κB蛋白表达显著下降(P0.05)。结论:抗衰老Klotho蛋白能够提升高糖作用下HUVECs的细胞活力,减少高糖诱导的ROS生成及氧化损伤,恢复HUVECs的正常分泌功能,并通过减少NF-κB蛋白表达发挥抗损伤作用。  相似文献   

4.
目的:探讨补肾宁心方对人单核-血管内皮细胞粘附的影响及机理。方法:以培养人脐静脉内皮细胞(HUVECs)作为靶细胞,在内皮细胞培养基中加入氧化的低密度脂蛋白(ox-LDL)或在试验体系中加入灌服补肾宁心方的兔血清,以孟加拉玫瑰红活细胞染色法测定人单核细胞系U937与HUVECs的粘附,并用流式细胞仪检测内皮细胞表面粘附分子细胞间粘附分子-1(ICAM-1)、血管细胞粘附分子-1(VCAM-1)以及E-选择素的表达。结果:ox-LDL显著增强单核U937细胞与内皮细胞之间的相互粘附,如在试验体系中加入灌服补肾宁心方的动物血清,则粘附率明显降低(P<0.01)。流式细胞仪分析结果显示ox-LDL能明显促进内皮细胞表面ICAM-1、VCAM-1以及E-选择素的表达,补肾宁心方中药灌服血清可显著下调内皮细胞表面ICAM-1、VCAM-1以及E-选择素的表达(P<0.01)。结论:补肾宁心方含药血清可能通过下调内皮细胞表面粘附分子的表达抑制单核-血管内皮细胞粘附,从而发挥对血管内皮细胞的保护作用。  相似文献   

5.
目的:探讨终末糖基化产物在糖尿病动脉粥样硬化(AS)形成中的作用机理。 方法: 分离正常人脐静脉内皮细胞(HUVECs),将终末糖基化终产物(AGE)修饰的人血清白蛋白(AGE-HSA)、人血清白蛋白(HSA)与HUVECs在体外共同培养,并用荧光单克隆抗体染色,流式细胞仪定量检测细胞间粘附分子-1(ICAM-1)、血管细胞粘附分子-1(VCAM-1)的表达。 结果: 正常人HUVEC表达ICAM-1和VCAM-1。AGE-HSA能以时间和剂量依赖的方式上调ICAM-1、VCAM-1的表达(P<0.05),而HSA对HUVECs上述粘附分子的表达均无影响。 结论: AGE能上调HUVECs粘附分子的表达,从而促进AS时单核/巨噬细胞的浸润。  相似文献   

6.
目的探讨氟伐他汀对C反应蛋白(C-reactive protein,CRP)诱导的人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs)细胞间黏附分子-1(intercellular adhesion molecule-1,ICAM-1)表达的影响。方法进行HUVECs原代培养,取第3~6代进行实验。分别以5、10、50和100mg/L浓度CRP作用HUVECs,分别作用6、12和24h,同时用氟伐他汀10-8、10-7、10-6和10-5mol/L浓度进行干预。用ELISA法测ICAM-1蛋白含量,RT-PCR测ICAM-1 mRNA表达。结果HUVECs对照组有少量ICAM-1蛋白和mRNA表达;CRP组ICAM-1蛋白和mRNA表达明显增强(P<0.01),且ICAM-1蛋白表达呈浓度和时间依赖性增加(P<0.01);氟伐他汀组ICAM-1蛋白及mRNA表达明显减弱(P<0.01),且氟伐他汀抑制CRP诱导的ICAM-1蛋白表达呈浓度依赖性(P<0.05)。结论氟伐他汀可能通过抑制CRP诱导ICAM-1产生,发挥抗动脉粥样硬化形成的作用。  相似文献   

7.
目的探讨miR-328对高糖诱导人脐静脉内皮细胞(HUVECs)上皮间质转换的调控作用及机制。方法培养HUVECs,构建携带miR-328基因的重组慢病毒,转染HUVECs。细胞分7组:正常葡萄糖、甘露醇、高浓度葡萄糖、miR-328、miR-328病毒阴性对照、高浓度葡萄糖+U0126、miR-328+U0126。免疫荧光双染色鉴定HUVECs间质转分化;RT-q PCR检测miR-328表达;Western blot检测Ⅰ、Ⅲ型胶原蛋白,MEK1/2、p-MEK1/2、ERK1/2、p-ERK1/2表达。结果 1)经高糖处理HUVECs呈CD31、α-SMA染色双阳性;2)与对照组比较,高糖组miR-328表达增高(P0.05);与高糖及miR-328组比较,U0126处理后miR-328表达降低(P0.05);3)与对照组比较,高糖及miR-328组Ⅰ、Ⅲ型胶原蛋白表达增多(P0.05);与高糖及miR-328组比较,U0126处理后Ⅰ、Ⅲ型胶原蛋白表达减少(P0.05);4)与对照组比较,高糖及miR-328处理后p-MEK1/2、p-ERK1/2表达增高(P0.05);而U0126处理则能抑制这一现象(P0.05)。结论高糖可诱导HUVECs上皮间质转换,同时miR-328表达增高;miR-328可诱导HUVECs上皮间质转换;HUVECs上皮间质转换与MEK1/2-ERK1/2信号通路有关。  相似文献   

8.
Inflammatory processes are involved in the pathogenesis of diabetic nephropathy. The aim of this study was to clarify the role of mitogen-activated protein kinase (MAPK) pathways for induction of intercellular adhesion molecule-1 (ICAM-1) expression in glomerular endothelial cells under diabetic conditions. We examined the expression of ICAM-1 in the kidneys of experimental diabetic rats. Human glomerular endothelial cells (GE cells) were exposed to normal glucose concentration, high glucose concentration (HG), or high mannitol concentration (HM), and then the expression of the ICAM-1 protein and the phosphorylation of the 3 subfamilies of mitogen-activated protein kinase (MAPK) were determined using Western blot analysis. Next, to evaluate the involvement of MAPKs in HG- or HM-induced ICAM-1 expression, we preincubated GE cells with the inhibitors for ERK, p38 or JNK 1h prior to the application of glucose or mannitol. Expression of ICAM-1 was increased in the glomeruli of diabetic rats. Both HG and HM induced ICAM-1 expression and phosphorylation of ERK1/2, p38 and JNK in GE cells. Expression of ICAM-1 was significantly attenuated by inhibitors of ERK, p38 and JNK. We conclude that activation of ERK1/2, p38 and JNK cascades may be involved in ICAM-1 expression in glomerular endothelial cells under diabetic conditions.  相似文献   

9.
目的:探讨MEK1/2在脂多糖诱导人脐静脉内皮细胞(HUVECs)ICAM-1表达中的作用。 方法: 用不同浓度LPS或LPS加MEK1/2特异性抑制剂PD98059和HUVECs孵育不同时间后,分别采用RT-PCR和Western blotting检测ICAM-1 mRNA和蛋白的表达。 结果: LPS呈时间-浓度依赖性地上调HUVECs ICAM-1 mRNA和蛋白的表达。LPS预处理后2 h,HUVECs ICAM-1 mRNA和蛋白的表达即开始升高,LPS(100 μg·L-1)作用后6 h,ICAM-1 mRNA和蛋白的表达基本达到高峰;PD98059(10 μg·L-1)可显著抑制LPS(100 μg·L-1)诱导6 h的ICAM-1 mRNA和蛋白的表达,抑制率分别为54.4%和44.9%(P<0.01 vs LPS)。 结论: 调控MEK1/2通路可能为内毒素休克诱导血管内皮损伤的防治提供新的策略。  相似文献   

10.
大量的单核细胞募集是动脉粥样损伤形成的早期表现之一,相关的内皮细胞粘附分子在其中具有积极作用。本文研究了溶血磷脂酰胆碱(Lysophosphatidylcholine,Lyso-PC)对培养的人脐静脉内皮细胞(HUVECs)膜上细胞间粘附分子-(Intercellular adhesion molecule-1,ICAM-1)、E选择素(Endothelial-leukocyte adhesion  相似文献   

11.
Extensive monocyte recruitment is an early phenomenon associated with the development of atherosclerotic lesions, suggesting an active role for the involvement of adhesion receptors expressed by endothelial cells. In this study we describe the contribution of hemodynamic shear forces in regulating the expression of a few of the monocyte adhesion receptors, including intercellular adhesion molecule (ICAM-1), vascular cell adhesion molecule (VCAM-1), and E-selectin on endothelial cells. A parallel plate flow chamber and recirculating flow loop device was used to expose human umbilical vein endothelial cells (HUVECs) to different levels of shear (2–25 dyn/cm2). Subsequently the cells were analyzed either for shear induced changes in the mRNA levels of adhesion receptors by Northern blot analyses or for changes in the surface expression of ICAM-1 using flow cytometry. Results from the fluorescence analysis showed a transient increase in the surface expression of ICAM-1, 12 hr after exposure to 25 dyn/cm2 shear, returning to basal levels within 24 hr. This was quite different from the time dependent response of ICAM-1 to lipopolysaccharide (LPS), where ICAM-1 expression was maximally induced 18–24 hr poststimulus. ICAM-1 mRNA level appeared slightly elevated after exposure to shear for 1 hr, compared to basal values, but dropped below basal levels within 6 hr. This biphasic response was seen irrespective of the magnitude of applied shear stress. VCAM-1 mRNA expression, in contrast, decreased below the baseline expression within an hour after onset of flow, and appeared to be considerably down-regulated within 6 hr. After exposure to shear for 24 hr no increase in mRNA levels could be detected for either molecule, at any shear magnitude. E-selectin mRNA was less responsive to shear stress, especially at the lower magnitudes of shear. After an hour of exposure to flow E-selectin mRNA level appeared slightly reduced compared with control levels, but it remained at this level even after 6 hr of flow. These results indicate that the expression of adhesion receptors is sensitive to local shear stresses in a manner that is molecule specific in the short term even though prolonged exposure to flow results in similar down-regulation for both ICAM-1 and VCAM-1.  相似文献   

12.
The aim this study was to investigate the effect of glucose on the induction of adhesion molecules by Human cytomegalovirus (HCMV) in endothelial cells in vitro. Primary cultures of human umbilical vein endothelial cells (HUVECs) pretreated with 16.5 mmol/l glucose for 24 hrs were infected with a HCMV strain with tropism for endothelial cells. Expression of adhesion nmolecules (ICAM-1, VCAM-1 and ELAM-1) was measured by flow cytometry. While high concentrations of glucoseperse activated the expression of all three adhesion molecules tested, HCMV induced the expression of ICAM-1 only. Moreover, it potentiated the expression of ICAM-1 in glucose-pretreated HUVECs, while it did not affect at all or slightly suppressed the glucose-activated expression of VCAM-1 and ELAM-1. The modulatory effect of glucose and HCMV on the expression of adhesion molecules in endothelial cells may be applied in increased vulnerability to patients with diabetes mellitus or atherosclerosis.  相似文献   

13.
在体内 ,内皮细胞的功能不仅受化学因子的调节 ,而且还受力学因素的影响。为探讨流体切应力和溶血磷脂酰胆碱 ( L ysophosphatidylcholine,L yso- PC)的双重作用对培养的人脐静脉内皮细胞 ( Hum an um bilical veinendothelial cells,HU VECs)表面黏附分子 ICAM- 1、VCAM- 1、E- selectin表达的影响 ,采用流式细胞仪技术检测了L yso- PC( 3 0 μg/m l)和流体切应力 ( 2 .2 3、4.2 0 dyne/cm2 )的协同作用下内皮细胞黏附分子表达的变化。结果显示 :在受剪切作用之前 ,用 L yso- PC孵育激活内皮细胞 ,或预先剪切后再用 L yso- PC孵育 ,内皮细胞的 ICAM- 1和VCAM- 1表达与两种刺激同时作用相比 ,显著增加 ( P<0 .0 5 ) ;切应力或 L yso- PC的单独作用 ,以及两种刺激同时存在对 HU VEC的 E- selectin表达无显著影响。而在受剪切作用之前 ,用 L yso- PC孵育激活内皮细胞 ,或预先剪切后再用 L yso- PC孵育 ,内皮细胞的 E- selectin表达与两种刺激同时作用相比 ,显著增加 ( P<0 .0 5 )。结论认为 :即使在不利于细胞黏附的力学环境中 ,流体切应力与 L yso- PC的协同作用 ,也可能是在炎症部位单核细胞对内皮细胞募集增加的重要原因之一  相似文献   

14.
15.
蜂胶水提物对血管内皮细胞黏附分子表达的影响   总被引:2,自引:2,他引:0       下载免费PDF全文
目的:采用TNF-α诱导体外培养的人脐静脉内皮细胞(HUCECs)活化,观察蜂胶水提物(WEP)对血管内皮细胞黏附分子表达的影响,从而探讨蜂胶抗动脉粥样硬化的作用及其机制。方法:用50μg/L TNF-α诱导体外培养HUVECs损伤,用50 mg/L、100 mg/L、200 mg/L WEP分别进行干预6 h、12 h、24 h,利用流式细胞仪检测HUVEC表面ICAM-1和VCAM-1表达。结果:与对照组比较,模型组ICAM-1和VCAM-1荧光强度明显升高(P0.01)。与模型组比较,100 mg/L WEP组和200 mg/L WEP组ICAM-1和VCAM-1荧光强度明显降低(P0.01)。不同浓度WEP组ICAM-1和VCAM-1荧光强度随WEP浓度的增加下调。析因分析结果显示,用200 mg/L WEP和氟伐他汀钠(FS)联合预处理组与单一药物预处理组比较,ICAM-1和VCAM-1活性明显降低(P0.01)。结论:WEP能够减少ICAM-1和VCAM-1的表达,且在一定的范围内,有随WEP浓度升高和作用时间延长效应增强的趋势。WEP与FS联合用药,对抑制ICAM-1和VCAM-1表达有协同作用。  相似文献   

16.
目的:观察肺炎衣原体对人脐静脉内皮细胞(HUVECs)的感染及其对细胞分泌和表达细胞间粘附分子1(ICAM-1)的影响,探讨C.pneumoniae感染在动脉粥样硬化形成中的作用及其可能机制。方法:用人喉表皮癌(HEP-2)细胞培养C.pneumoniae,以C.pneumoniae感染HUVE细胞,经透射电镜及PCR检测有无感染。用流式细胞仪检测感染前后HUVE细胞表面ICAM-1蛋白的表达的变化,用荧光定量RT-PCR检测ICAM-1mRNA的变化。结果:C.pneumoniae能感染体外培养的HUVE细胞;感染后12h,细胞表面ICAM-1蛋白的表达即增加,其峰值约在感染后24h;荧光定量RT-PCR结果显示其增加在mRNA水平。结论:C.pneumoniae能感染体外培养的人脐静脉内皮细胞并增加ICAM-1的表达,提示C.pneumoniae感染可能是动脉粥样硬化的始动因子之一,其致动脉粥样硬化机制可能与感染后血管内皮细胞粘附分子表达的增加有关。  相似文献   

17.
Little is known about the role of isorhamnetin on endothelial cell apoptosis and inflammation when insulted by TNF-α injury. In our study, HUVECs were treated with TNF-α for 6 hours. HUVECs apoptosis were detected using flow cytometry. The expressions of ICAM-1, VCAM-1, E-selectin, NF-κB, AP-1 and eNOS were determined with western blotting or flow cytometry. The results showed TNF-α increased of apoptosis and the expression of ICAM-1, VCAM-1 and E-selectin in HUVECs, accompanied by significant augmentation of NF-κB and AP-1 expression. Pretreatment with isorhamnetin significantly reduced apoptosis in TNF-α-treated HUVECs. Moreover, isorhamnetin significantly attenuated TNF-α-induced upregulation of ICAM-1, VCAM-1, AP-1, E-selectin and NF-κB expression. Meanwhile, isorhamnetin also increased the expression of eNOS. So, isorhamnetin could suppress TNF-α-induced apoptosis and inflammation by blocking NF-κB and AP-1 signaling in HUVECs, which might be one of the underlying mechanisms for treatment of coronary heart disease.  相似文献   

18.
Using a quantitative monolayer adhesion assay, the current report shows that treatment of human umbilical vein endothelial cells (HUVEC) with IL-6 increases their adhesiveness for blood lymphocytes, particularly CD4+ cells, but not for polymorphonuclear cells and monocytes. This effect, which was most pronounced when using low concentrations of the cytokine (0.1–1.0 U/ml) and a short incubation period (4 h), was also apparent with microvascular endothelial cells and a hybrid endothelial cell line. Skin lesions from patients with mycosis fungoides contain high levels of IL-6, and blood lymphocytes from patients with this disorder also exhibited an enhanced adhesion to IL-6-treated HUVEC. The cytokine enhanced intercellular adhesion molecule-1 (ICAM-1) expression and induced the expression of vascular cell adhesion molecule-1 (VCAM-1) and E-selectin on endothelial cells. Antibody blocking studies demonstrated that the vascular adhesion molecules ICAM-1, VCAM-1 and E-selectin and the leucocyte integrin LFA-1 all contributed to lymphocyte binding to endothelium activated by IL-6. It is proposed that IL-6 may be involved in the recruitment of lymphocytes into non-lymphoid tissue.  相似文献   

19.
目的:观察体外不同浓度葡萄糖对大鼠肾小球内皮细胞(rRGECs)表达低氧诱导因子1α(HIF-1α)、血管内皮生长因子A(VEGFA)及血管内皮钙黏素(VE-cadherin)的影响,探讨红景天苷减轻高糖诱导rRGECs损伤的作用及可能相关机制。方法:体外培养rRGECs,分为正常糖组、高糖(20、30和50 mmol/L)组、高渗组及红景天苷+高糖组。采用MTT法检测rRGECs的活力;RT-qPCR法检测rRGECs内HIF-1α、VEGFA及VE-cadherin的mRNA表达;Western blot法检测rRGECs内HIF-1α蛋白的表达。结果:与正常糖组相比,培养24 h后,高糖(20mmol/L)组rRGECs HIF-1α的mRNA及蛋白表达均上调(P 0.05);培养120 h后,高糖组HIF-1αmRNA表达下调(P 0.05)。与正常糖组相比,培养24 h和120 h后,高糖组rRGECs内VE-cadherin的mRNA表达下调(P 0.05)。与正常糖组相比,培养24 h后,高糖组rRGECs内VEGFA的mRNA表达上调(P 0.05);培养120 h后,高糖组rRGECs内VEGFA的mRNA表达下调(P 0.05)。与正常糖组相比,培养24 h和120 h后,高渗组rRGECs内HIF-1α、VE-cadherin及VEGFA的mRNA表达无变化。与高糖组相比,培养24 h后,红景天苷(50μmol/L)组rRGECs的活力增加(P 0.01),且细胞内HIF-1α和VE-cadherin的mRNA及HIF-1α蛋白表达均上调(P 0.05)。结论:体外高糖培养能影响rRGECs表达HIF-1α,可能与细胞活力、葡萄糖的浓度、作用时间及HIF/VEGF通路有关。红景天苷能减轻高糖诱导的rRGECs损伤,其机制可能与增加rRGECs内HIF-1α的表达有关。  相似文献   

20.
The present study was designed to establish (i) the effects of cytokines on soluble ICAM-1 (sICAM-1) production by human synovial cells (SC) and ICAM-1 expression on these cells, and (ii) the effects of sICAM-1 on lymphocyte-SC adhesion. sICAM-1 production was enhanced in parallel with ICAM-1 expression by IL-1 beta, TNF-alpha and IFN-gamma. IL-4 showed no effects on ICAM-1 expression. In contrast with the transient elevation of cell-associated ICAM-1 by IL-1 beta, which peaked 36 h after stimulation and declined thereafter, sICAM-1 continued to accumulate in culture supernatants even after 48 h. Purified sICAM-1 was obtained from a 48 h culture synovial cell supernatant by affinity chromatography using ICAM-1 monoclonal antibody. The purified sICAM-1 significantly inhibited adhesion of lymphocytes and monocytes to cytokine-stimulated synovial cells. These results suggest that sICAM-1 may modulate chronic synovitis by inhibiting ICAM-1-mediated cell-to-cell adhesion.  相似文献   

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