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1.
人精原干细胞特异性标志的初步筛选   总被引:13,自引:3,他引:10  
目的:寻求可能用于人精原干细胞(SSC)分离和纯化的特异性表面标志。方法:通过免疫组化方法,应用造血干细胞(HSC)表面标志c-kit、Thy-1,人胚胎干细胞(ES)表面标志阶段特异性胚胎抗原SSEA-3、SSEA-4、碱性磷酸酶(ALP),原始生殖细胞(PGC)标志SSEA-1以及小鼠SSC表面标志α6和β1整合素对成人及胎儿睾丸SSC的特异性表达进行筛选和鉴定。结果:在成人睾丸组织中,α6整合素在生精小管生殖细胞表面存在较广泛而显著阳性表达,而β1整合素主要在生精小管基底部细胞存在显著阳性染色,Thy-1在成人睾丸生精小管基底部细胞可见散在阳性染色,少量间质细胞中亦可见阳性染色。上述3种抗原标志在成人生殖细胞表面的表达具有一定的特异性。在胎儿睾丸生精小管中,可见SSEA-1在生殖细胞表面存在显著阳性表达,具有明显特异性。结论:α6、β1整合素和Thy-1可作为阳性标志用于人SSC的分选。SSEA-1可作为识别胎儿SSC的特异性标志。  相似文献   

2.
目的 :分离、鉴定和培养人精原干细胞(SSC),以获得纯化、富集的人SSC并为其研究与应用奠定基础。方法:通过免疫荧光方法检测睾丸组织中CD90表达情况;应用两步酶消化和差速贴壁法分离人睾丸生精细胞,以CD90为人SSC标志,用免疫磁珠分选技术(MACS)对人睾丸生精细胞进行分选,并利用RT-PCR和免疫细胞化学对分选所得CD90+细胞进行鉴定;同时用SG培养液将CD90+细胞与支持细胞进行体外共培养。结果:MACS分选所得CD90+细胞大小、形态特征较为均一,RT-PCR检测其表达人SSC标记性基因,免疫荧光检测其高表达人SSC特异标记GFRA-1、GPR125和UCHL-1,阳性率达90.5%,其在SG培养液中与支持细胞共培养14 d后仍可保持良好活性。结论:CD90可作为人SSC特异性标志之一,结合差速贴壁和MACS可高效分选人SSC,分选所得SSC可在SG培养液中进行体外培养。  相似文献   

3.
目的:通过特异抗体结合的磁珠分选,改进小鼠未分化和分化中两类精原细胞分选方法。方法:利用Thy1和c-Kit两个特异抗体结合的磁珠分选技术,分别将出生后7 d雄性小鼠睾丸中的Thy1~+细胞和c-Kit~+细胞分别做为未分化和分化中的精原细胞分选出来,利用免疫荧光技术和流式细胞术,检测两种精原细胞的纯度,利用实时荧光定量PCR检测两种精原细胞中Gfrα1、Plzf、c-kit和sohlh2 mRNA的表达差异来鉴定两种精原细胞,并将Thy1~+细胞进行原代细胞培养。结果:Thy1~+细胞和c-Kit~+细胞的分选纯度分别达到(85.6±8.35)%和(89.40±2.77)%(P0.01)。Thy1~+细胞中Gfrα1和Plzf基因的相对表达量分别可达到c-Kit~+细胞的(9.47±1.29)、(4.40±0.59)倍,而在c-Kit~+细胞中kit和sohlh2基因的相对表达量分别可达到Thy1~+细胞的(7.38±1.07)、(3.88±0.28)倍(P0.01)。原代培养后,可见细胞状态良好,能够顺利的自我增殖,并具有精原干细胞增殖特征。结论:利用Thy1和c-Kit两个特异抗体结合的磁珠分选技术可以有效地将未分化和分化中的精原细胞分选出来,并将未分化的精原细胞进行体外培养。  相似文献   

4.
目的:检测人表皮细胞中是否存在侧群(side population,SP)细胞,并研究该表型细胞是否表达通用干细胞标志物ABCG2和表皮干细胞的标志物整合素α6和β1.方法:运用中性蛋白酶和胰蛋白酶两步消化法从手术切除的人包皮组织中分离获得表皮细胞.经Hoechst33342荧光染料和PI染色,流式细胞仪分析并分选SP细胞.采用流式细胞仪分析SP细胞ABCG2、整合素α6和β1的表达情况.结果:人表皮细胞中存在SP细胞,其比例为0.2%~0.3%.用流式细胞仪可检测到在SP细胞以及总表皮细胞中均有少量细胞表达通用干细胞标志物ABCG2以及表皮干细胞的标志物整合素α6和β1,但二者阳性细胞百分比差异无统计学意义(P>0.05).结论:表皮细胞中的SP细胞是否是富集的表皮干细胞仍存在疑问,还需要进一步的动物体内移植实验、克隆形成能力和增殖能力的研究证实.  相似文献   

5.
目的 建立小鼠精原干细胞(SSC)长期培养体系,探讨SSC体外增殖分化的关键因子.方法 收集出生4~6 d BALB/c绿色荧光小鼠睾丸,采用改良两步消化法获得细胞悬液,3次差速贴壁去除体细胞获得富集的精原细胞,采用添加生长因子的无血清基础培养液重悬,种植到小鼠胚胎成纤维细胞饲养层上培养.基础培养液为StemPro-34 SFM干细胞培养基并补充15种添加成分;生长因子为10 ng/ml碱性成纤维细胞因子、20 ng/ml胶质细胞源性神经营养因子和200 ng/mlGDNF家族受体a1.取4~5周龄BALB/c雄性小鼠15只,腹腔注射40 mg/kg的白消安建立受体模型,采用三维显微注射系统将培养的SSC移植到受体左侧睾丸精曲小管内,右侧睾丸作为自身对照;分别采用体视荧光显微镜观察和HE染色检测细胞移植后睾丸生精功能恢复情况.结果 改良消化富集法消化后细胞活性>98%,SSC富集约18.5倍.饲养层培养1~2 d后细胞成对称或线形排列,细胞间可见明显的胞质桥连接.3~4 d后精原细胞增殖形成典型的克隆,为边缘不清楚的团块;小鼠SSC能在该培养体系中稳定培养、传代3个月.移植后2个月,体视荧光显微镜下受体睾丸内可见明显绿色阳性克隆,HE染色证实移植的SSC在受体睾丸内克隆增殖并分化产生成熟的精子.结论 成功建立了BALB/c小鼠SSC培养体系,为研究SSC增殖分化调控机制及SSC移植治疗男性不育提供了实验依据.  相似文献   

6.
目的改进Leydig干细胞的分离及纯化方法,观察其生物学特性并进行鉴定。方法通过胶原酶消化、差速贴壁法及双抗体免疫磁珠分选法,从大鼠睾丸内获得Leydig于细胞。以条件培养液进行培养,采用CCK法测定增殖能力。通过PDGFRα、LIFR及3β-HSD免疫组织化学染色鉴定Leydig干细胞。经定向诱导分化后,检测Leydig细胞的睾酮分泌能力。结果每个睾丸约可获得83000个干细胞,经免疫组织化学染色分析,PDGFRα阳性率为(98.0±0.8)%。在条件培养液中培养的SLCs增殖明显,在1个月内能稳定维持其干性而未向Leydig细胞系分化。免疫组织化学染色结果表明,PDGFRα、LIFR阳性表达,3B—HSD为阴性表达。Leydig干细胞在含有T3和HCG的培养液中培养后,第5天即可测到睾酮分泌,分化后的细胞3β-HSD^+。结论由差速贴壁法及双抗体免疫磁珠分选法能获得纯化的PDGFRcC/LHα^+/细胞,这些细胞符合SLCs所必须具有的特征。采用该方法获取SLCs,操作简便,细胞损伤小并且获取纯度高。  相似文献   

7.
人精原干细胞的体外培养及其功能鉴定   总被引:2,自引:1,他引:1  
目的:通过应用多种培养条件下的生殖细胞共培养体系,寻求人精原干细胞(SSC)长期体外生存和扩增的优化途径。方法:应用磁式分选所获得的α6+Thy-1+c-k it-细胞,分别以STO、MEF、Sertoli细胞为饲养层,于DMEM/F12、DMEM或DMEM-SF培养液条件下短期培养,然后选择胎儿Sertoli细胞作为共培养体系,在32℃、5%CO2、DMEM/F12(含10%胎牛血清)培养条件下,分别观察成人和胎儿生殖细胞的长期培养结果。并应用免疫组化技术和SSC移植技术对培养细胞进行初步生物学特性和功能鉴定。结果:在短期培养中,α6+Thy-1+c-k it-细胞在存在饲养层时,可在DMEM和DMEM/F12培养液中稳定生存,1周内存活率可达90%。长期培养条件下,α6+Thy-1+c-k it-细胞逐渐与Sertoli细胞形成紧密的贴附或镶嵌关系,呈单个、成对、短链状或小团簇状;胎儿SSC与成人类似,部分以圆球形散在分布于Sertoli细胞表面,并常可观察到明显的成对或短链状细胞,部分呈有突起的长梭形扁平细胞,与Sertoli细胞相互形成紧密连接;经反复传代3个月,仍可观察到稳定存在的圆球形SSC贴附于Ser-toli细胞表面。由PKH26标记的α6+Thy-1+c-k it-细胞在移植后2个月可迁移至裸鼠生精小管基膜,表现为单个或成对的细胞。生精小管内荧光细胞计数显示α6+Thy-1+c-k it-细胞在体外培养2、4周后仍然保留54.9%和9.2%的SSC。结论:该培养系统的进一步优化将有利于体外产生大量SSC,并有助于进一步深入了解SSC的生物学特性和男性生精功能障碍的治疗。  相似文献   

8.
目的探讨应用免疫磁珠细胞分选方法分离肾癌细胞株786-O中CD133+的可能性,并分析CD133+细胞与CD133-细胞的基因表达谱差异。方法应用免疫磁珠细胞分选技术分选肾癌细胞株786-O中的CD133+细胞,流式细胞仪分析CD133细胞含量,提取RNA用基因芯片技术分析其基因表达谱。结果 786-O细胞中CD133+细胞占13.70%,磁珠分选收集的CD133+细胞阳性率可达98.46%。免疫磁珠细胞分选技术可以有效分选肾癌CD133+细胞,基因表达谱分析可见CD133+细胞较CD133-细胞有8种基因表达上调2倍以上,23种基因下调2倍以上。结论免疫磁珠细胞分选技术可以有效分离肾癌CD133+细胞,CD133+细胞与CD133-细胞表达差异基因分析为后续研究提供了新的思路。  相似文献   

9.
目的探讨转化生长因子β1(TGF-β1)和溶血磷脂酸(LPA)是否能诱导整合素αvβ6在肝细胞性肝癌中的过度表达。方法收集23例肝细胞癌患者的组织标本,采用免疫组织化学方法检测整合素αvβ6蛋白的表达水平。培养人肝癌细胞Hep-3B,以正常肝细胞(HL-7702)为对照,采用逆转录PCR(RT-PCR)法检测整合素αvβ6表达,再分别用TGF-β1和(或)LPA刺激Hep-3B细胞,Western Blotting法检测整合素αvβ6蛋白的表达水平,实时荧光定量PCR(Real-time PCR)法检测Hep-3B中整合素αvβ6的m RNA表达水平。结果 (1)免疫组织化学检测显示整合素αvβ6在肝癌标本中呈高表达,而在正常肝脏组织中并不表达。(2)逆转录PCR检测Hep-3B细胞表达整合素αvβ6,在正常肝细胞中未发现表达。(3)Western Blotting、实时定量PCR结果显示TGF-β1、LPA和TGF-β1+LPA均可诱导Hep-3B细胞过度表达整合素αvβ6,差异有统计学意义(P0.05)。结论整合素αvβ6在肝癌组织及Hep-3B细胞中呈高表达。TGF-β1和LPA可诱导整合素αvβ6在Hep-3B细胞中过度表达,这将有望为肝癌的诊断和治疗提供新的潜在治疗靶点。  相似文献   

10.
目的 研究PIWIL2在人膀胱癌肿瘤干细胞样细胞(CSLC)中的表达和意义,探讨PIWIL2在靶向肿瘤干细胞治疗中的作用.方法 用无血清悬浮培养法从人膀胱移行细胞癌细胞株BIU-87中分离获得悬浮细胞球,流式细胞仪检测细胞表面分子标志CD133和CD44的表达,免疫磁珠分选系统分离CD133+CD44+细胞;分别采用T...  相似文献   

11.
Wang R  Li J  Lyte K  Yashpal NK  Fellows F  Goodyer CG 《Diabetes》2005,54(7):2080-2089
The integrin receptors play a major role in tissue morphogenesis and homeostasis by regulating cell interactions with extracellular matrix proteins. We have examined the expression pattern of integrin subunits in the human fetal pancreas (8-20 weeks fetal age) and the relevance of beta1 integrin function for insulin gene expression and islet cell survival. Its subunits alpha3, alpha5, and alpha6 beta1 integrins are expressed in ductal cells at 8 weeks, before glucagon- and insulin-immunoreactive cells bud off; their levels gradually increase in both ductal cells and islet clusters up to 20 weeks. Colocalization of alpha3, alpha5 and alpha6 beta1 integrins with endocrine cell markers was frequently observed in 8- to 20-week fetal pancreatic cells. When the beta1 integrin receptor was functionally blocked in cultured islet-epithelial clusters with a beta1 immunoneutralizing antibody or following transient beta1 integrin small interfering RNA treatment, there was inhibition of cell adhesion to extracellular matrices, decreased expression of insulin, and increased cell apoptosis. These data offer evidence for dynamic and cell-specific changes in integrin expression during human pancreatic islet neogenesis. They also provide an initial insight into a molecular basis for cell-matrix interactions during islet development and suggest that beta1 integrin plays a vital role in regulating islet cell adhesion, gene expression, and survival.  相似文献   

12.
Gronthos S  Simmons PJ  Graves SE  Robey PG 《BONE》2001,28(2):174-181
To date, the precise interactions between bone marrow stromal cells and the extracellular matrix that govern stromal cell development remain unclear. The integrin super-family of cell-surface adhesion molecules represents a major pathway used by virtually all cell types to interact with different extracellular matrix components. In this study, purified populations of stromal precursor cells were isolated from the STRO-1-positive fraction of normal human marrow, by fluoresence-activated cell sorting, and then assayed for their ability to initiate clonogenic growth in the presence of various integrin ligands. Bone marrow-derived stromal progenitors displayed differential growth to fibronectin, vitronectin, and laminin, over collagen types I and III, but showed a similar affinity for collagen type IV. The integrin heterodimers alpha1beta1, alpha2beta1, alpha5beta1, alpha6beta1, alpha(v)beta3, and alpha(v)beta5 were found to coexpress with the STRO-1 antigen on the cell surface of CFU-F, using dual-color analysis. Furthermore, only a proportion of stromal precursors expressed the integrin alpha4beta1, while no measurable levels of the integrin alpha3beta1 could be detected. Subsequent adhesion studies using functional blocking antibodies to different integrin alpha/beta heterodimers showed that stromal cell growth on collagen, laminin, and fibronectin was mediated by multiple beta1 integrins. In contrast, cloning efficiency in the presence of vitronectin was mediated in part by alpha(v)beta3. When human marrow stromal cells were cultured under osteoinductive conditions, their ability to form a mineralized matrix in vitro was significantly diminished in the presence of a functional blocking monoclonal antibody to the beta1 integrin subunit. The results of this study indicate that beta1 integrins appear to be the predominant adhesion receptor subfamily utilized by stromal precursor cells to adhere and proliferate utilizing matrix glycoproteins commonly found in the bone marrow microenvironment and bone surfaces. Furthermore, these data suggest a possible role for the beta1 integrin subfamily during the development of stromal precursor cells into functional osteoblast-like cells.  相似文献   

13.
We previously showed that a local immune response largely composed of type 1 T cells correlated with a favorable outcome of the peritonitis associated with peritoneal dialysis. To clarify how these subsets are recruited to the peritoneal cavity during inflammation, we measured integrin-mediated interactions between the T cells and human peritoneal mesothelial cells. Direct microscopy showed that lipopolysaccharide or peritoneal dialysis effluent stimulated the adherence of T cells to mesothelial cells, a process mediated by the integrins alpha6beta1 and alpha4beta1. Further, the migration of Th1 cell across human mesothelial cell monolayers grown on transwell surfaces was reduced by anti-alpha6beta1 integrin antibody while that of Th2 cell was inhibited by an anti-alpha4 integrin antibody. Pretreatment with either lipopolysaccharide or rapid response peritoneal dialysis effluent stimulated T cell migration and this was significantly decreased by the alpha6beta1 compared to the alpha4 antibody. These results suggest that integrins may play an important role in mediating selective T cell subset adhesion and migration across human peritoneal mesothelial cell monolayers and differential integrin expression and selective T cell subset recruitment during peritonitis may affect outcome.  相似文献   

14.
BACKGROUND: Cell-matrix interactions via integrin receptors are critical for acinar morphogenesis. The non-tumorigenic, human prostate epithelial cell line RWPE-1 was used in a three-dimensional (3D) cell culture model to identify the matrix protein and its integrin receptor required for acinar morphogenesis. METHODS: 3D cultures, immunostaining, confocal microscopy, and Western blot analysis were used to examine acinar formation on matrix proteins and to determine integrin receptor expression. RESULTS: RWPE-1 cells differentiate into acini of polarized cells with a distinct lumen in 3D Matrigel culture. In contrast, the malignant WPE1-NB26 prostate epithelial cells form solid cell masses. In 3D gels of laminin-1, type IV collagen, or fibronectin, RWPE-1 cells form acini only in laminin-1. Anti-laminin-1 antibody reduces acinar formation in a dose-dependent manner. Polarized RWPE-1 cells showed basal expression of alpha6 and beta1 integrin subunits. Blocking antibodies to alpha6 or beta1 reduced acinar formation to 9 and 6 percent of control, respectively. The beta1 integrin colocalized with focal adhesion kinase (FAK). Inhibition of extracellular signal-regulated kinase kinase activity significantly reduced acinar formation to 38 percent of control, suggesting that beta1 integrin-mediated signal transduction may be regulated through a FAK pathway. CONCLUSIONS: While basal expression of alpha6beta1 integrin in RWPE-1 cells correlates with their ability to polarize and form acini, a decrease or loss of alpha6, and diffused beta1 expression in WPE1-NB26 cells correlates with loss of acinar-forming ability. Results show that laminin-1 and a functional alpha6beta1 integrin receptor are required for acinar morphogenesis. This novel 3D cell culture model is useful for elucidating regulation of acinar morphogenesis and its loss during prostate carcinogenesis.  相似文献   

15.
The alpha6beta1 integrin heterodimer has been implicated in the mediation of renal epithelial cell binding to laminin, and it has been suggested that this binding is important for renal morphogenesis and development. Studies of nonrenal cells have suggested that the functional activity of alpha6beta1 integrin is regulated by protein kinase C (PKC) activity. In this study, the binding of a renal epithelial cell line, LLC-PK1, to laminin was characterized and the role of PKC activity in the modulation of binding was investigated. LLC-PK1 cells bound to laminin-coated surfaces in a time- and laminin concentration-dependent manner. Binding was strongly inhibited by anti-beta1 integrin antibodies and by anti-alpha6 integrin antibodies. Antibodies against alpha2 integrin and a3 integrin had little inhibitory effect. Cells bound to both whole laminin and laminin fragment E8, i.e., the fragment to which the alpha6beta1 integrin heterodimer binds. Exposure of cells to PKC activators for as little as 2 h enhanced cell binding to laminin approximately twofold, in a protein synthesis-dependent manner. PKC inhibitors antagonized this effect. PKC-stimulated binding was also inhibited by anti-beta1 integrin and anti-alpha6 integrin antibodies. PKC activation did not alter expression of beta1 integrin subunits at the cell surface after short time periods (2 to 4 h), but expression was increased after longer time periods (24 h). These results indicate that the renal epithelial cell line LLC-PK1 binds to laminin via the alpha6betal integrin heterodimer and binding is enhanced by PKC activation. The PKC-mediated enhancement of binding requires protein synthesis and is mediated in part by activation of surface alpha6beta1 integrin.  相似文献   

16.
BACKGROUND: Tumor cell plasticity represents a significant clinical challenge in that the fate and function of tumor cells can be elusive until a tumor mass is evident. A remarkable example of plasticity is tumor cell vasculogenic mimicry, recently described in aggressive uveal and cutaneous melanoma, in addition to ovarian carcinoma, whereby tumor cells express endothelial-associated genes and form de novo vasculogenic-like networks in three-dimensional (3-D) culture. In the current investigation, we examined whether there is evidence for vasculogenic mimicry in heterogeneous prostatic neoplasms. METHODS: Dunning rat and human prostate cancer cell lines (comprised of epithelial- and fibroblastic-like tumor subpopulations) were tested for their ability to express selected endothelial-associated genes, laminin, the alpha6beta1 laminin-binding integrin, and for their potential to form perfusable tubular networks in 3-D culture. Simultaneous morphological analysis of tumor-lined channels in rat and human tumors was also performed. RESULTS: Green fluorescent protein labeling of prostatic clonal subpopulations revealed unique cooperative interactions of epithelial- and fibroblastic-like tumor cells in the formation of perfusable vasculogenic-like networks. Furthermore, while these cell lines were shown to express various vascular markers, prostatic tumor cell-lined channels were also detected in vivo in high grade tumors, and occurred in some cases in close proximity to conventional endothelial-lined vasculature. CONCLUSIONS: A multidisciplinary approach to assess vasculogenic mimicry by prostatic tumor cells has revealed supportive evidence that it occurs in invasive, heterogeneous prostate cancer cell lines, and circumstantially in aggressive rat and human tumors. These results reflect the plasticity of aggressive prostatic tumor cells and may provide new prognostic markers for clinical diagnosis and new therapeutic intervention strategies.  相似文献   

17.
人真皮微淋巴管内皮细胞的分离培养和鉴定   总被引:2,自引:0,他引:2  
目的建立人真皮来源淋巴管内皮细胞(LECs)分离和培养的方法。方法采用中性蛋白酶及胶原酶消化方法结合免疫磁珠从真皮组织分选CD34-/CD31 细胞。免疫细胞化学、免疫荧光及逆转录-聚合酶链反应(RT-PCR)方法检测LECs特异标志的表达,噻唑蓝(MTT)比色试验测定多种与内皮细胞增殖相关的细胞因子和低氧条件对其增殖的影响。结果CD34-/CD31 细胞在单层细胞培养时形成内皮细胞典型的铺路石样外观,而在胶原凝胶三维培养时形成管状结构。CD34-/CD31 细胞表达淋巴管内皮细胞特异性标志,包括LYVE-1,VEGFR-3和Prox-1。RT- PCR显示Proxl和VEGFR-3 mRNA在CD34-/CD31 细胞中特异性表达。特异作用于淋巴管内皮细胞的VEGF-C对LECs的促增殖作用明显(P<0.01)。低氧条件和Ang2在体外未显示对LECs有促进增殖的作用。结论应用中性蛋白酶及胶原酶消化方法结合免疫磁珠分选可以成功分离获取人真皮LECs。  相似文献   

18.
TGF-beta1 is a potent osteoactive factor and exhibits a wide variety of effects on osteoblasts, most of which are mediated through receptor associated Smad proteins. We have recently reported a novel TGF-beta1 intracellular Ca2+ signaling pathway in osteoblasts, and found that this signaling is required for the TGF-beta1 mediated enhancement of osteoblast adhesion to substrate. Given that interaction between the extracellular matrix protein fibronectin and alpha5beta1 integrin on the cell surface is principally responsible for osteoblast substrate adhesion, we examined here whether the TGF-beta1 stimulated Ca2+ signal is involved in this pathway. Our results show that, in primary human osteoblasts, the TGF-beta1 induced intracellular Ca2+ signal is responsible, in part, for the stimulation of expression of alpha5 integrin, but not of beta1 integrin or fibronectin. Increased levels of alpha5 integrin protein and mRNA were seen as early as 12 h after TGF-beta1 treatment, but were inhibited by co-treatment of cells with nifedipine, a selective L-type Ca2+ channel blocker. TGF-beta1 treatment increased both fibronectin and beta1 integrin protein production within 48 h, in a manner unaffected by co-treatment with nifedipine. Immunofluorescence observations revealed that TGF-beta1 treatment resulted in increased alpha5 integrin staining, and more prominent alpha5 integrin clustering, with increased co-localization with the actin cytoskeleton, effects that were blocked by co-treatment with nifedipine. The TGF-beta1 induced intracellular Ca2+ signal in human osteoblasts is thus an important mechanistic step in the regulation of alpha5 integrin expression, later contributing to enhanced cell adhesion.  相似文献   

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