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1.
Vertical fractionation of a mixture of fixed horse and human red blood cells layered over a stabilizing support medium was done to give a valid comparison with proposed space experiments. In particular, the effects of sample thickness and concentration on zone migration rate were investigated. Electrophoretic mobilities of horse and human cells calculated from zone migration rates were compatible with those obtained by microelectrophoresis. Complete cell separation was observed when low power and effective cooling were employed.  相似文献   

2.
目的:探讨人脐带间充质干细胞条件培养基联合白藜芦醇对人绒毛膜外滋养层细胞凋亡的影响。方法:通过CCK8细胞活力检测试剂盒测定白藜芦醇及其与人脐带间充质干细胞条件培养基共同处理人绒毛膜外滋养层细胞HTR8后对细胞增殖及活性的影响;细胞迁移试验检测白藜芦醇和人脐带间充质干细胞条件培养基对细胞迁移能力的影响;显微镜观察细胞形态,并用流式细胞仪检测细胞凋亡率的变化;Western blot检测白藜芦醇和人脐带间充质干细胞条件培养基对细胞凋亡相关蛋白Bax、Bcl-2以及迁移相关蛋白MMP-9表达的影响。结果:白藜芦醇能够抑制HTR8细胞增殖,抑制细胞迁移及MMP-9蛋白的表达,改变Bax和Bcl-2蛋白表达诱导细胞凋亡的作用。而人脐带间充质干细胞条件培养基能够逆转白藜芦醇对细胞的抑制作用。结论:人脐带间充质干细胞条件培养基能够通过调控Bax、Bcl-2、MMP-9的蛋白表达逆转白藜芦醇对人绒毛膜外滋养层细胞的抑制作用。人脐带间充质干细胞条件培养基可作为潜在的治疗人绒毛膜外滋养层细胞功能障碍的临床手段,孕妇需要小心使用白藜芦醇。  相似文献   

3.
目的:研究Sprouty2(SPRY2)基因在胃癌肿瘤细胞上皮间质转化(EMT)和侵袭转移的影响。方法:体外培养人胃癌细胞(BGC-823),采用慢病毒介导的sh RNA沉默SPRY2基因,并用实时定量PCR与Western blot检测其SPRY2、E-钙黏蛋白(E-cadherin)、波形蛋白(vimentin)的表达,采用细胞划痕实验、Transwell实验检测SPRY2基因沉默后的胃癌细胞侵袭转移能力变化。结果:在慢病毒介导sh RNA沉默SPRY2基因的人胃癌BGC-823细胞中,SPRY2的m RNA和蛋白表达明显降低(P0.05),SPRY2沉默后人胃癌细胞E-cadherin的蛋白表达增多(P0.05),vimentin的蛋白表达减少(P0.05)。此外,SPRY2沉默后,胃癌细胞迁移能力和侵袭能力明显减弱(P值均P0.05)。结论:Sprouty-2基因通过调节E-cadherin与vimentin的表达参与胃癌细胞的上皮-间质转化,进而促进胃癌细胞的迁移与侵袭。  相似文献   

4.
目的:研究微小核糖核酸-145(microRNA-145,miRNA-145)对人牙周膜成纤维细胞迁移的影响及其作用机制。方法:体外采用酶消化法培养人牙周膜成纤维细胞并传代,将其分为对照组和转染miRNA-145组,按50 ng/mL的miRNA-145浓度转染人牙周膜成纤维细胞,转染72 h后提取各组蛋白,用Western blot检测miRNA-145的靶蛋白ROCK1的表达水平的相关变化;采用划痕试验检测各组划痕细胞间距离的相关变化,选取划痕后的0 h、24 h、48 h、72 h时间点,测量各时间点划痕细胞间的距离并计算平均值。结果:与对照组相比,转染miRNA-145后,miRNA-145靶蛋白ROCK1的表达量显著降低(p0.05);转染24 h、48 h后细胞间距离的均值大于对照组(p0.05)。结论:miRNA-145可能通过下调ROCK1的表达抑制人牙周膜成纤维细胞的迁移。  相似文献   

5.
目的:探讨蜕皮激素诱导迁移侵袭抑制蛋白基因(migration and invasion inhibitory protein,MIIP)基因的表达对肝癌细胞SK-Hep-1增殖和迁移能力的影响。方法:采用PCR扩增MIIP基因,连入T载体测序正确后,插入到蜕皮激素可诱导真核表达载体pIND中。将pIND-MIIP和含蜕皮激素受体基因的表达载体pVgRXR以脂质体转染法转染到SK-Hep-1中,经G418和Zeocin双抗生素筛选获得稳定转染细胞株。蜕皮激素Ponasterone A诱导后,采用Western blot检测MIIP表达,CCK-8实验检测细胞增殖,划痕实验检测细胞迁移。结果:蜕皮激素诱导MIIP表达上调后,SK-Hep-1细胞的增殖能力显著下降(P0.05),细胞的迁移能力明显减弱。结论:建立了MIIP基因可诱导表达系统,证实在肝癌细胞SK-Hep-1中MIIP过表达可抑制细胞的增殖及迁移能力。  相似文献   

6.
AimsFormation of different protrusive structures by migrating cells is driven by actin polymerization at the plasma membrane region. Gelsolin is an actin binding protein controlling the length of actin filaments by its severing and capping activity. The main goal of this study was to determine the effect of gelsolin expression on the migration of human colon adenocarcinoma LS180 and melanoma A375 cells.Main methodsColon adenocarcinoma cell line LS180 was stably transfected with plasmid containing human cytoplasmic gelsolin cDNA tagged to enhanced green fluorescence protein (EGFP). Melanoma A375 cells were transfected with siRNAs directed against gelsolin. Real-time PCR and Western blotting were used to determine the level of gelsolin. The ability of actin to inhibit DNase I activity was used to quantify monomeric and total actin level and calculate the state of actin polymerization. Fluorescence confocal microscopy was applied to observe gelsolin and vinculin distribution along with actin cytoskeleton organization.Key findingsIncreased level of gelsolin expression leads to its accumulation at the submembranous region of the cell accompanied by distinct changes in the state of actin polymerization and an increase in the migration of LS180 cells. In addition, LS180 cells overexpressing gelsolin form podosome-like structures as indicated by vinculin redistribution and its colocalization with gelsolin and actin. Downregulation of gelsolin expression in melanoma A375 cells significantly reduces their migratory potential.SignificanceOur experimental data indicate that alterations in the expression level of gelsolin and its subcellular distribution may be directly responsible for determining migration capacity of human cancer cells.  相似文献   

7.
目的:骨肉瘤是一种常见的恶性骨肿瘤,恶性程度高,往往在早期就会发生远隔器官的转移,从而导致骨肉瘤的预后非常差。Orai1是一类定位于细胞膜,介导钙离子内流的受体依赖性钙通道蛋白。大量研究发现钙通道蛋白Orai1过表达于多种肿瘤细胞,并对维持肿瘤细胞粘附、侵袭、迁移等恶性表型有非常重要的作用。然而,钙通道蛋白Orai1是否参与了骨肉瘤的转移过程,目前未见相关报道。本研究的目的是探究钙通道蛋白Orai1是否在骨肉瘤转移过程中的发挥作用。方法:利用合成的靶向Orai1的小干扰RNA(Orai1 si RNA)片段,转染至人骨肉瘤细胞系Saos-2细胞。在Saos-2细胞中抑制Orai1的表达。采用细胞黏附实验、细胞划痕实验和细胞Transwell实验检测骨肉瘤细胞的黏附、迁移及侵袭等肿瘤细胞转移能力;Western-blot实验检测Saos-2细胞的中黏着斑激酶(FAK)和桩蛋白(Paxillin)的表达水平和磷酸化水平。结果:靶向Orai1 si RNA瞬时转染至骨肉瘤细胞系Saos-2细胞后,Saos-2细胞中Orai1蛋白表达水平和m RNA转录水平均显著下降。并且,在Saos-2细胞中抑制Orai1表达后,Saos-2细胞的黏附能力、迁移能力、及侵袭能力均显著下降。进一步研究发现,在Saos-2细胞中抑制Orai1表达后,Saos-2细胞的FAK和Paxillin磷酸化水平明显下降。结论:Orai1可以促进骨肉瘤细胞的黏附、迁移和侵袭,增加黏着斑的形成,从而促进骨肉瘤的转移。因此,深入研究钙通道蛋白Orai1调控骨肉瘤转移的分子机制,可为骨肉瘤转移的治疗提供新的新方向和新策略。  相似文献   

8.
《Cytotherapy》2023,25(9):946-955
Background aimsWhile distraction osteogenesis (DO) achieves substantial bone regeneration, prolonged fixation may lead to infections. Existing stem cell and physical therapies have limitations, requiring the development of novel therapeutic approaches. Here, we evaluated high-mobility group box 1 (HMGB1) as a novel therapeutic target for DO treatment.MethodsMicro-computed tomography (Micro-CT) analysis and histological staining of samples obtained from tibial DO model mice was performed. Transwell migration, wound healing, and proliferation assays were also performed on cultured human mesenchymal stem cells (hMSCs) and human umbilival vein endothelial cells (HUVECs). Tube formation assay was performed on HUVECs, whereas osteogenic differentiation assay was performed on hMSCs.ResultsMicro-CT analysis and histological staining of mouse samples revealed that HMGB1 promotes bone regeneration during DO via the recruitment of PDGFRα and Sca-1 positve (PαS+) cells and endothelial progenitor cells. Furthermore, HMGB1 accelerated angiogenesis during DO, promoted the migration and osteogenic differentiation of hMSCs as well as the proliferation, migration and angiogenesis of HUVECs in vitro.ConclusionsOur findings suggest that HMGB1 has a positive influence on endogenous stem/progenitor cells, representing a novel therapeutic target for the acceleration of DO-driven bone regeneration.  相似文献   

9.
ABSTRACT

Physiological responses that occur in horses and humans during their interactions, on the ground and during ridden work, have been investigated in a number of studies with some conflicting results. These suggest that in some situations emotional state may be transferred from humans to horses and that there is the potential for the heart rates of horse–human pairs to become synchronized during ridden work. Here we explore the effect of familiarity on the physiological responses of horse–human pairs completing a task in-hand, using heart rate as an indicator for emotional state. We investigated differences in heart rate response between familiar and unfamiliar pairings and the possibility of heart rate synchronization within each pair. Complete sets of horse and human heart rate data were available for 17 horses. We found a significant order affect, with higher horse heart rates seen the first time around the course regardless of whether a familiar or unfamiliar handler was leading (Wilcoxon test: Z=–2.67, p<0.05). However, despite this, the horses’ mean heart rates for each course were significantly higher with the unfamiliar handler than with the familiar handler (Wilcoxon test: Z=–4.46, p<0.001). In contrast, human heart rates were higher when paired with a familiar horse compared with an unfamiliar horse (Mann-Whitney U test: Z=–5.08, p<0.001). Significant correlations between horse and human heart rates were seen in three familiar pairings and two unfamiliar pairings. Our findings indicate that the relationship between horse and human heart rates during interactions is not straightforward or consistent between horses and humans, and is likely to depend on a number of factors such as experience of the test situation. Although the lower heart rates seen in horses being led by their familiar handler suggest that they are more relaxed with someone they know, this could not be said for the human partner.  相似文献   

10.
摘要 目的:研究白藜芦醇(RES)通过蛋白酪氨酸激酶2/信号转导子与激活子3(JAK2/STAT3)信号通路对人骨肉瘤体外细胞株MG-63细胞凋亡、侵袭和迁移的影响。方法:体外培养MG-63细胞,以不同浓度的RES作用于MG-63细胞。Annexin V-FITC/PI双染流式细胞术检测不同时间和不同浓度的RES对MG-63细胞凋亡的影响。划痕实验和Transwell实验检测不同时间和不同浓度的RES对MG-63细胞侵袭和迁移能力的影响。免疫印迹实验检测不同时间和不同浓度的RES对MG-63细胞磷酸化蛋白酪氨酸激酶2(p-JAK2)、磷酸化信号转导子与激活子3(p-STAT3)、凋亡相关蛋白B淋巴细胞瘤-2(Bcl-2)、Bcl-2家族促凋亡蛋白(Bax)及基质金属蛋白酶(MMP)-2、MMP-9表达的影响。结果:RES浓度越高,时间越久,MG-63细胞凋亡率越高(P<0.05)。RES浓度越高,MG-63细胞迁移和侵袭能力越弱(P<0.05)。RES处理MG-63细胞后其p-JAK2、p-STAT3、Bcl-2以及MMP-2、MMP-9的表达明显降低,而Bax蛋白表达明显升高,且p-JAK2、p-STAT3、Bax、Bcl-2以及MMP-2、MMP-9的表达水平变化具有RES浓度依赖性(P<0.05)。结论:RES可能通过调控JAK2/STAT3信号通路促使人骨肉瘤MG-63细胞凋亡,并抑制MG-63细胞侵袭和迁移。  相似文献   

11.
BackgroundMore than 80% of advanced prostate cancer (PCa) cases have bone metastasis, with a 5-year survival rate of 25%. Previously, we reported that GRT, a standardized, pharmaceutical-grade aspalathin-rich extract (12.78 g aspalathin/100 g extract), prepared from green rooibos produced from the leaves and fine stems of Aspalathus linearis, inhibits the proliferation of PCa cells, meriting this investigation to determine if GRT can suppress the migration and invasion of castration-resistant prostate cancer (CRPC) cells.PurposeIn the present study, we investigated whether GRT extract can interfere with the migration and invasion of human CRPC cells.MethodsTranswell assays were used to explore the effects of GRT on the migration and invasion of CRPC cells. Micro-Western Array (MWA) and Western blot analysis were carried out to unravel the underlying molecular mechanism(s).ResultsTreatment with 25–100 μg/ml GRT suppressed the migration and invasion of LNCaP C4-2B and 22Rv1 CRPC cells. MWA and Western blot analysis indicated that GRT treatment suppressed the protein level of yes-associated protein (YAP), macrophage stimulating 1 protein (MST1), phospho-MST1/phospho-MST2 T183/T180, and paxillin, but increased the abundance of E-cadherin. Over-expression of YAP rescued the suppressive effects of GRT on migration and invasion of CRPC cells. Treatment with the major flavonoid of GRT — the C-glucosyl dihydrochalcone, aspalathin — at a concentration of 75–100 μg/ml also reduced the migration and invasion of CRPC cells, and the inhibition was partially rescued by YAP over-expression.ConclusionsGRT treatment suppresses the migration and invasion of CRPC cells via inhibition of YAP signaling and paxillin.  相似文献   

12.
《Anthrozo?s》2013,26(4):323-331
Abstract

To assess the effects of human confidence levels on horse behavior, 40 veterinary students led the same mare around a fixed course. Multivariate analysis of human attitudes and behavior and horse behavior showed that a positive attitude towards horses related to infrequent ear movement in that horse (accounting for 46% of variance); positive attitude, together with low lead tension, related to a horse's forward ear position (47%); loose lead tension related to both a horse's low resistance (66%) and low head position (11%). Human attitudes towards at least one horse is shown to be associated with changes in human behavior, which leads to altered behavior in that horse.  相似文献   

13.
目的:外泌体是活细胞分泌的来源于多囊泡体的膜性囊泡,其主要作用包括携带与运输。雪旺细胞是周围神经再生中非常优秀的种子细胞,但其迁移能力较差,影响修复效果。本文旨在探讨外泌体和雪旺细胞共培养是否可以促进雪旺细胞迁移。方法:本实验通过分离纯化人脐带干细胞外泌体和大鼠坐骨神经雪旺细胞并鉴定,随后将其共培养于Transwell小室观察雪旺细胞迁移率。结果:通过人脐带干细胞超高速离心法得到的外泌体高表达干细胞标志物CD44(92.2±3.6%)、CD73(99.1±0.6%),并且低表达单核细胞表面抗原CD14(0.5±0.06%)以及造血干细胞表面抗原CD34(0.4±0.07%),外泌体鉴定高表达CD81和CD9;雪旺细胞培养鉴定纯度达(92.3±2.7)%;均符合实验要求。通过Transwell小室实验发现外泌体可以明显促进雪旺细胞的迁移,并且具有一定剂量关系。结论:外泌体可以提高雪旺细胞的迁移能力,从而使雪旺细胞在组织工程领域中的应用产生巨大突破。  相似文献   

14.
神经再生(Neurogenesis)是指具有自我更新能力的神经干细胞(Neural Stem Cells,NSCs)经过迁移、增殖,最终分化为具有特定功能的神经细胞的过程。以往人们认为,神经再生只存在于胚胎期或外周神经系统,近几年发现,在成年动物的中枢神经系统也存在神经再生,研究发现侧脑室室管膜下区(SVZ)是神经再生发生的主要区域之一,产生新的神经元和神经胶质细胞通过RMS通路运输至嗅球进而对嗅觉损伤部分进行修复。本文主要从成年神经再生的发展、神经再生与疾病的关系、神经再生的过程等方面进行综述。  相似文献   

15.
目的:探讨瞬时受体电位通道C3(TRPC3)对人卵巢癌细胞迁移、侵袭能力的影响。方法:采用蛋白免疫印迹法和实时荧光定量PCR法分别检测卵巢癌细胞株SKOV3、ES-2和HEY-T30中TRPC3蛋白和m RNA的表达水平。通过Transwell迁移实验(不含Matrigel胶的Transwell小室)和Transwell侵袭实验分别检测卵巢癌细胞株SKOV3、ES-2和HEY-T30的迁移、侵袭能力。结果:在SKOV3、ES-2和HEY-T30三种卵巢癌细胞株中,ES-2中TRPC3的蛋白和m RNA表达均显著高于其他两株(P0.05)。Transwell迁移实验和Transwell侵袭实验显示卵巢癌细胞株ES-2的迁移、侵袭能力均显著高于其他两种细胞株(P0.05)。结论:瞬时受体电位通道C3(TRPC3)在ES-2人卵巢癌细胞中高表达,并可能促进人卵巢癌细胞的迁移、侵袭。  相似文献   

16.
目的:探讨Notch信号通路对肝癌细胞迁移能力及钙粘附蛋白E(E-cadherin)、环氧化酶-2(COX-2)表达的影响。方法:体外培养肝癌细胞系(SMMC-7721、MHCC97H)、正常非肿瘤肝细胞系(HL-7702),Transwell小室用于测定细胞的迁移侵袭能力,Western blot蛋白印迹法用于测定Notch1、E-cadherin、COX-2蛋白的表达水平,并采用DAPT阻断Notch信号通路,比较肝癌细胞系与正常非肿瘤肝细胞系的迁移侵袭能力及肝癌细胞中E-cadherin、COX-2蛋白的表达水平的改变。结果:SMMC-7721细胞、MHCC97H细胞的迁移能力强于HL-7702细胞,差异有统计学意义(P0.05);相比于HL-7702细胞,MHCC97H细胞、SMMC-7721细胞中的Notch1、COX-2表达水平均显著升高,E-cadherin的表达水平明显降低(P0.05);DAPT处理后,SMMC-7721细胞、MHCC97H细胞发生迁移的能力均弱于对照组,差异有统计意义(P0.05);DAPT处理后,SMMC-7721细胞、MHCC97H细胞内COX-2、Notch1的表达量明显降低,而E-cadherin的表达水平升高(P0.05)。结论:Notch信号通路参与肝癌细胞迁移过程,其机制可能与E-cadherin、COX-2的表达相关。  相似文献   

17.
ABSTRACT

To elucidate the underlying mechanism of secretory leukocyte protease inhibitor (SLPI)-induced cell migration, we compared SLPI-deleted human gingival carcinoma Ca9-22 (ΔSLPI) cells and original (wild-type: wt) Ca9-22 cells using several microscopic imaging methods and gene expression analysis. Our results indicated reduced migration of ΔSLPI cells compared to wtCa9-22 cells. The lamellipodia/dorsal ruffles were smaller and moved slower in ΔSLPI cells compared to wtCa9-22 cells. Furthermore, well-developed intermediate filament bundles were observed at the desmosome junction of ΔSLPI cells. In addition, Galectin4 was strongly expressed in ΔSLPI cells, and its forced expression suppressed migration of wtCa9-22 cells. Taken together, SLPI facilitates cell migration by regulating lamellipodia/ruffles and desmosomes, in which Galectin4 plays an important role.  相似文献   

18.
Background aimsNon-irradiated immunodeficient recipients provide the best physiologic setting for revealing hematopoietic stem cell (HSC) functions after xenotransplantion. An approach that efficiently permits the detection of human hematopoietic repopulating cells in non-irradiated recipients is therefore highly desired.MethodsWe compared side-by-side the ability to reconstitute hematopoiesis via intra-bone marrow transplantation (IBMT) in three commonly used mouse strains avoiding previous irradiation.ResultsNon-irradiated NOD/SCID and NOD/SCID (β2m?/? mouse strains prevent engraftment even after IBMT. In contrast, combining the robustness of the NOD/SCID IL-2Rγ?/? recipient with the sensitivity of IBMT facilitates the detection, without previous host irradiation, of human SCID-repopulating cells 10 weeks after transplantation. The level of chimerism averaged 14% and multilineage engraftment (lymphoid dominant) was observed consistently in all mice. Analysis of injected and non-injected bones, spleen and peripheral blood demonstrated that engrafting cells were capable of in vivo migration and expansion.ConclusionsCombining the robustness of the NOD/SCID IL-2Rγ?/? mouse strain with the sensitivity of IBMT strongly facilitates long-term multilineage engraftment and migration for human CD34+ cells without the need for previous irradiation.  相似文献   

19.
AimsClaudin expression is altered in lung cancer, but the pathophysiological role of claudin is not well understood. We examined the effect of claudin-2 expression on cell migration using human adenocarcinoma A549 cells.Main methodsThe mRNA level was measured by real time polymerase chain reaction. To knockdown claudin-2 expression, we made the cells expressing doxycycline-inducible claudin-2 shRNA vector. The protein level was examined by Western blotting. Cell migration was measured by wound-healing assay. The enzymatic activity of MMP-9 was assessed by gelatin zymography.Key findingsIn A549 cells, claudin-2 expression was higher than in normal lung tissue. Claudin-2 knockdown did not affect the expression of other junctional proteins including claudin-1, occludin and E-cadherin. Claudin-2 knockdown decreased cell migration concomitant with a decrease in the mRNA level and enzymatic activity of MMP-9. The expression level of Sp1 in the nuclei was decreased by claudin-2 knockdown. In contrast, the expression levels of c-Fos, c-Jun and NF-kB p65 in the nuclei were not changed by claudin-2 knockdown. The knockdown of Sp1 expression by siRNA decreased cell migration, and the mRNA expression, enzymatic activity, and promoter activity of MMP-9.SignificanceClaudin-2 may increase the mRNA level and enzymatic activity of MMP-9 mediated by the elevation of nuclear distribution of Sp1, resulting in the up-regulation of A549 cell migration.  相似文献   

20.
摘要 目的:探讨长链非编码RNA(LncRNA)MYU对胶质瘤细胞周期分布、细胞增殖、迁移、侵袭和凋亡的影响,并初步探讨其作用机制。方法:实时荧光定量PCR(RT-qPCR)检测人脑正常胶质细胞HEB和胶质瘤细胞(U-251MG、A172、SHG139)中LncRNA MYU的表达情况。选取SHG139细胞,分为正常对照(NC)组、si-con组、si-LncRNA MYU组进行转染实验,行RT-qPCR检测转染效果。分别采用流式细胞术、细胞计数试剂盒(CCK-8)、Transwell实验检测沉默LncRNA MYU对SHG139细胞周期分布和凋亡、细胞增殖、细胞迁移和侵袭的影响。蛋白免疫印迹(Western blot)法检测基质金属蛋白酶2(MMP-2)、MMP-9、裂解的半胱氨酸天冬氨酸蛋白酶3(Cleaved caspase-3)、Cleaved caspase-9以及磷脂酰肌醇-3-羟激酶/蛋白激酶B(PI3K/Akt)信号通路相关蛋白表达情况。结果:LncRNA MYU在胶质瘤细胞株中比人脑正常胶质细胞中的表达水平显著升高(P<0.05),因此选择表达量最高的SHG139细胞进行转染实验。沉默LncRNA MYU能够显著诱导SHG139细胞G0-G1期阻滞、抑制细胞增殖、迁移和侵袭并诱导细胞凋亡(P<0.05)。沉默LncRNA MYU可显著抑制MMP-2、MMP-9、p-PI3K和p-AKT表达并促进Cleaved caspase-3、Cleaved caspase-9表达(P<0.05)。结论:沉默LncRNA MYU可诱导胶质瘤细胞G0-G1期阻滞,抑制细胞增殖、迁移和侵袭,促进细胞凋亡,其机制可能与抑制PI3K/AKT信号通路有关。  相似文献   

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