首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 182 毫秒
1.
Mao JF  Liu SZ  Qin WJ  Xiang Q  Wu XY 《眼科学报》2011,26(4):211-216
 Purpose:In our previous work, it has been shown that intraperitoneal injection of L-DOPA can inhibit the development of occlusion myopia in guinea pigs, and increase levels of retinal dopamine. The aim of this study was to investigate whether exogenous L-DOPA can be converted into dopamine in cultured retina of guinea pig eyes subjected to visual deprivation, and to evaluate whether müller cells are involved in the processing of retinal dopamine induced by L-DOPA. Methods:Fifty-eight guinea pigs were randomly divided into 2 groups at the age of 4 weeks: normal control and visual deprivation. Form deprivation was induced with translucent eye shields over the right eye, and lasted for ten days. Corneal curvature, refraction and axial length were measured in all animals. In vitro, neuro-retina and müller cell were cultured, and L-DOPA was added to the culture medium at three concentrations: 1μM, 10μM and 100μM. Subsequently, dopamine content was evaluated by high-performance liquid chromatography, and apoptotic cells were identified by TUNEL staining. Results:Ten days of occlusion caused the affected eyes to elongate and become myopic in guinea pigs. Compared with the deprivation group, 10цM L-DOPA treament significantly raised dopamine content in cultured retina and müller cells (P<0.05). However, 1μM and 100μM L-DOPA treatment caused no increase in dopamine levels (P>0.05). Apoptotic nuclei were detected in the ganglion cell layer (92.5%±8.3%) and inner nuclear layer (46.8%±9.1%) of cultured retina treated with 100 μM L-DOPA. Moreover, 100 цM L-DOPA also caused apoptosis of retinal müller cells, at a mean rate of 59.4 ±11.3%. Conclusion:Our results suggest that exogenous L-DOPA can cause an increase in retinal dopamine in form-deprived guinea pig eyes in vitro, and that müller cells are involved in the increase in retinal dopamine.  相似文献   

2.
3.
Objective To investigate the feasibility of Y27632 to induce transdifferentiation from human retinal pigment epithelial(hRPE)cells into neuron-like cells in vitro.Methods The third to sixth generation of primary hRPE cells were cultured with 2% fetal bovine serum+Dulbecco's modified eagle medium/F12 culture solution,with(experimental group)or without(control group)10 μmol/L Y27632.At 3,6 hours and 1,3,5,7 days after induction,the morphologic changes of RPE cells were observed by inverted microscope.The expression rate of CK18,Map2,NF200 and Pax6 at 3 days after induction in the experimental and control group were detected by immunofluorescent staining.χ2 test was employed for comparison between the two groups.Results 50.1% cells of the experimental group formed axon-like processes and interconnected each other with typical neuron-like appearance.The expression rates of CK18,Map2,NF200 and Pax6 in the experimental group were 43.88% ,31.90% ,57.45% and 65.79% .while the above indexes in the control group were 93.97% ,4.49% ,22.37% and 8.33% respectively.Compared the expression rate of CK18(χ2=64.763),Map2(χ2=23.634),NF200(χ2=21.261)and Pax6(χ2=25.946)between the two groups,the differences were significant(P<0.01).Conclusion The hRPE cells can be trans-differentiated into neuron-like cells in vitro bv Y27632.  相似文献   

4.
5.
Jian  Ge  Minkai  Lin 《眼科学报》1998,14(3):134-137
Purpose : To establish the culture system of human glaucomatous trabecular cells in vitro and study their ultrastructures.Methods : The trabecular specimens from trabeculectomy were cultured in vitro and passaged 3 times, then identified. Moreover, the glaucomatous cells were observed with electron microscope while compared with the normal ones.Result: Cultured human glaucomatous trabecular cells were obtained. The ultrastructure of the cells showed the decrease in vilious project, coated vesicle and lysosomal inclusion. Conclusion : The establishment of human glaucomatous trabecular cells culture in vitro made the culture system more perfect. The morphologic changes might be related to the abnormal functions of human trabecular meshwork cells. Eye Science 1998; 14 : 134 - 737.  相似文献   

6.
Objective To investigate the feasibility of Y27632 to induce transdifferentiation from human retinal pigment epithelial(hRPE)cells into neuron-like cells in vitro.Methods The third to sixth generation of primary hRPE cells were cultured with 2% fetal bovine serum+Dulbecco's modified eagle medium/F12 culture solution,with(experimental group)or without(control group)10 μmol/L Y27632.At 3,6 hours and 1,3,5,7 days after induction,the morphologic changes of RPE cells were observed by inverted microscope.The expression rate of CK18,Map2,NF200 and Pax6 at 3 days after induction in the experimental and control group were detected by immunofluorescent staining.χ2 test was employed for comparison between the two groups.Results 50.1% cells of the experimental group formed axon-like processes and interconnected each other with typical neuron-like appearance.The expression rates of CK18,Map2,NF200 and Pax6 in the experimental group were 43.88% ,31.90% ,57.45% and 65.79% .while the above indexes in the control group were 93.97% ,4.49% ,22.37% and 8.33% respectively.Compared the expression rate of CK18(χ2=64.763),Map2(χ2=23.634),NF200(χ2=21.261)and Pax6(χ2=25.946)between the two groups,the differences were significant(P<0.01).Conclusion The hRPE cells can be trans-differentiated into neuron-like cells in vitro bv Y27632.  相似文献   

7.
Objective To investigate the effect of pressure bionic culture on the morphology and function of rabbit corneal endothelial cells. Methods Corneal endothelial cells were separated and purified by tearing apart the descemet and digesting with trypsin and EDTA, then cultured in the plate. The cells were divided into two groups: group A were cultured under atmosphere; cells exposed to 2 kPa( 14. 66 mm Hg) pressure in vitro was group B; the morphology and growth pattern of cells were observed by inverted microscope; cells origin were identified by neuron-specific enolase immunoassay. Cellular changes in the structure were observed by HE staining and scanning and transmission electron microscopy (SEM and TEM) analysis. Cells activity was detected by flow cytometry. Results NSE antibody of the primary corneal endothelial cells was positive without corneal epithelial cells and corneal stroma cells. Two groups of cells were cultured for 120-144 h respectively, the morphology was flat, polygon, most of cells were hexagon and abundant cytoplasms in group B (pressure bionic culture), but in group A, the cells size was not uniform and there were much granules in the cytoplasm. There was no difference in the time of formation of monolayer in two groups. SEM showed that cells exposed to pressure connected tightly and the surface was rich in microvilli, extended foot processes and attached to the substrate tightly, while cells cultured under atmosphere with more off-chip. In group B, Annexiv-FITC/PI detection of apoptosis showed cell survival rate was 98.2%, early apoptosis rate was 0.7%, late apoptosis rate was 1.0%, death rate was 0. 1%; the corresponding data were 92.2%, 5.2%, 2.3%, and 0.3% in group A, respectively; There was statistically significant difference between the two groups (x2 =594. 0,P <0. 01 ). After cultured for 96 h,the expression of ZO-1 protein in cells exposed to pressure was higher than those in control. Conclusions The biological activity of endothelial cells is regulated positively by bionic pressure. The establishment of a new biomimetic pressure model will help to investigate the physiological function and injury repair of corneal endothelial cells in vitro.  相似文献   

8.
Purpose:To study preliminarily in vitro induced differentiation of embryonic stem cells into neurons for further investigation of an alternative for the treatment of glaumatous neuropathy.Materials and methods:Supernatant of cultured Buffalo rat liver cells(buffalorat liver cell-conditioned medium,BRL-CM)was used for culturing embryonic stem cells(ES-D3 cell line),Morphological features of undifferentiated EScells were studied by HE staining and electron microscopy.Based on the methods used by Bain et al,we modified the methods and used retinoic acid(RA)as an inducer to differentiate ES-D3 cells and cytosine arabinoside(Ara-C)as inhibitor of proliferative cells.The growth of the cells was observed under phase contrast microscope.Results:ES-D3cells cultured by BRL-CMgrew in aggregates and remained undifferentiated.Electromicroscopy showed large nucleus and a large amount of mitochondria in undifferentiated ES cells and many processes on the surfaces.In the first day after the adding of retinoic acid,some neuron-like cells with one,two or more processes were present.In the second day after adding RAand the first day after the plus of 10μm Ara-C,a large amount of neuron-like cells appeared,with the formation of neuron-like networks.Con clusions:Combined use of RA and Ara-Ccan induce ES cells to differentiate into neuron-like cells.Our present preliminary study might provide insights into an alternative for the treatment of glaucomatous neuropathy by the transplantation of embryonic stem cells.Eye Science2000;16:1-6.  相似文献   

9.
Objective To investigate the effect of pressure bionic culture on the morphology and function of rabbit corneal endothelial cells. Methods Corneal endothelial cells were separated and purified by tearing apart the descemet and digesting with trypsin and EDTA, then cultured in the plate. The cells were divided into two groups: group A were cultured under atmosphere; cells exposed to 2 kPa( 14. 66 mm Hg) pressure in vitro was group B; the morphology and growth pattern of cells were observed by inverted microscope; cells origin were identified by neuron-specific enolase immunoassay. Cellular changes in the structure were observed by HE staining and scanning and transmission electron microscopy (SEM and TEM) analysis. Cells activity was detected by flow cytometry. Results NSE antibody of the primary corneal endothelial cells was positive without corneal epithelial cells and corneal stroma cells. Two groups of cells were cultured for 120-144 h respectively, the morphology was flat, polygon, most of cells were hexagon and abundant cytoplasms in group B (pressure bionic culture), but in group A, the cells size was not uniform and there were much granules in the cytoplasm. There was no difference in the time of formation of monolayer in two groups. SEM showed that cells exposed to pressure connected tightly and the surface was rich in microvilli, extended foot processes and attached to the substrate tightly, while cells cultured under atmosphere with more off-chip. In group B, Annexiv-FITC/PI detection of apoptosis showed cell survival rate was 98.2%, early apoptosis rate was 0.7%, late apoptosis rate was 1.0%, death rate was 0. 1%; the corresponding data were 92.2%, 5.2%, 2.3%, and 0.3% in group A, respectively; There was statistically significant difference between the two groups (x2 =594. 0,P <0. 01 ). After cultured for 96 h,the expression of ZO-1 protein in cells exposed to pressure was higher than those in control. Conclusions The biological activity of endothelial cells is regulated positively by bionic pressure. The establishment of a new biomimetic pressure model will help to investigate the physiological function and injury repair of corneal endothelial cells in vitro.  相似文献   

10.
11.
胚胎与成人视网膜神经细胞培养   总被引:4,自引:0,他引:4  
目的 建立胚胎及成人视网膜神经细胞体外培养系统,为视网膜神经细胞的基础研究与药物开发提供实验模型。 方法 10~13周龄胎儿及20~40岁成人视网膜神经层用不同的酶进行消化,分散的细胞接种于预先经过包被的细胞培养盘内,加入或不加入表皮生长因子(epidermal growth factor, EGF)、成纤维细胞生长因子(fibroblast growth factor, FGF)、脑源性神经营养因子(brainderived neurotrophic factor, BDNF)、神经营养素 4(neurotrophic-4,NT-4)等培养。通过BrdU掺入、免疫组织化学及免疫荧光等方法检测培养细胞增殖并辨别细胞成分。 结果 胚胎及成人视网膜细胞可在体外连续培养100及180 d以上。加入EGF、FGF、BDNF或NT-4可明显促进胚胎与成人视网膜神经元存活,胎儿视网膜细胞增殖。与对照组相比,处理组神经元或神经节细胞的百分率较高。 结论 胚胎及成人视网膜神经细胞培养技术为视网膜神经细胞基础研究及药物开发提供了一种十分有价值的手段,加入外源性的生长因子可促进培养的视网膜神经细胞存活、增殖与分化。 (中华眼底病杂志, 2002, 18: 279-282)  相似文献   

12.
目的:探寻一种既高效又能连续体外扩增视网膜前体细胞(RetinalProgenitorCell,RPC)的培养方法。方法:小鼠胚胎视网膜细胞采取神经球贴壁培养或直接贴壁培养法。神经球贴壁培养时,先经悬浮培养生成富含前体细胞的神经球,然后将低速离心分离出的神经球接种到Poly-D-Lysine包被的培养瓶,在前体细胞培养液中(含FGF-2、EGF和LIF)贴壁培养,头24h在培养液中添加10%的胎牛血清。直接贴壁培养法是将细胞悬液直接接种到预先包被Poly-D-Lysine的培养瓶。免疫组化和FACS分析神经球贴壁培养细胞的干细胞特性和分化能力,并与直接贴壁培养法得到的细胞进行比较。结果:神经球接种到预先包被Poly-D-Lysine的培养瓶后贴附到培养瓶底,逐渐形成贴壁生长的单层细胞。该法能够在体外长期扩增视网膜前体细胞,3个月内细胞能够传代10次以上。在RA诱导分化时,能够生成成熟视网膜细胞,表达视网膜细胞特异性标记。FACS分析和免疫组化染色显示神经球贴壁培养所得细胞在未分化时Nestin阳性率(92%)细胞率以及分化为成熟视网膜细胞的比率(53.7%),均高于直接贴壁培养法获得的细胞。结论:神经球贴壁培养法能够在体外长期大量扩增视网膜前体细胞,能较好地保持干细胞特性,并容易分化为成熟的视网膜细胞,较直接贴壁培养具有较大的优越性。  相似文献   

13.
黄蔚  王琳  惠延年  马吉献 《眼科学报》2002,18(4):235-239
目的:探讨雪旺细胞(Schwann cells,SC)源营养神经活性物质(SC derived neurotrophic activity,SCNA)对体外培养视网膜节细胞正常及缺血损伤环境中存活及生长相关蛋白(GAP)43表达的作用。方法:培养乳鼠SC,制备不同蛋白浓度的SCNA,加入原代培养的视网膜细胞中,MTT法检测SCNA活性培养荧光金逆行标记的新生3d的SD乳鼠视网膜细胞,接种于24孔板中。培养第2d时SCNA作用组培养液中加入300mg/L SCNA,对照组不加;培养第5d缺气损伤组在培养液表面加入液体石蜡造成缺气损伤。12h后去除液体石蜡,观察细胞形态和计数荧光金逆行标记的视网膜节细胞(retinal ganglion cell,RGC).Western Blot法分析SCNA对视网膜细胞GAP43表达的影响。结果:SCNA能促进培养视网膜细胞的存活,并有蛋白浓度依赖关系。加SCNA后,视网膜细胞生长明显旺盛,悬浮的死细胞较少,RGC数量明显多于视网膜细胞单纯培养组(F=62.89,P<0.01)。缺气损伤组视网膜细胞出现肿胀改变,加有SCNA缺气损伤组细胞形态大致正常,RGC数与对照组相比有显著性差异(F=49.27,P<0.01)。GAP43的表达在视网膜细胞正常及缺气损伤SCNA作用组上调。结论:SCNA对培养RGC具有明显营养作用,并上调GAP43的表达。在培养液中加入SCNA,可以减轻“缺气”造成的损伤,提高体外培养RGC在损伤环境中的存活。  相似文献   

14.
Liu WW  Xu P  Huang Q 《中华眼科杂志》2003,39(9):545-549
目的 探讨成人视网膜神经细胞体外培养条件 ,脑源性神经营养因子 (BDNF)、神经营养素 (NT 4 )、表皮生长因子 (EGF)、成纤维细胞生长因子 (FGF)、诱导分化因子全反式视黄酸 (RA)等对成人视网膜神经细胞生长、增殖、凋亡的影响及调控机制。方法 胰蛋白酶消化结合机械吹打分离成人视网膜神经细胞 ,在培养基中加入或不加入BDNF、NT 4、EGF、FGF、RA。根据细胞形态、生长方式及免疫细胞化学特征确定细胞类型。比较各组中神经元的数目、转录调控因子c fos、c jun及细胞凋亡调控因子Bcl 2、Bax表达水平。结果 与对照组相比 ,BDNF、FGF处理组存活的神经元特异性烯醇酶、Thy1.1抗体和Bcl 2、c fos及c jun表达阳性细胞数也增多 (均P <0 0 1) ,培养的视网膜神经细胞在体外存活时间可长达 8个月 ;RA处理组c fos、c jun阳性细胞数较对照组增多 (均P <0 0 1) ;而NT 4、EGF处理组各项指标与对照组比较 ,差异无显著意义 (均P >0 0 5 )。结论 BDNF、FGF、RA能显著提高体外培养的成人视网膜神经细胞的存活 ,其机制可能涉及上调转录调控因子c fos、c jun及凋亡抑制因子Bcl 2的表达 ,或下调凋亡促进因子Bax的表达。但EGF、NT 4对体外培养的视网膜神经细胞存活状态无明显改善作用。  相似文献   

15.
We describe here a culture method which allows the growth of dissociated mouse retinal neurons and photoreceptors in chemically defined medium. Neural retinas from 2-day-old C57/BL mice were dissected from other ocular tissues, including the pigment epithelium, and dissociated into a cell suspension after brief trypsination. Most cells attached as single, unaggregated units to substrata pretreated with polyornithine and the neurite-promoting factor (PNPF). The cells were cultured in serum-free, high pyruvate Dulbecco's modified Eagle's medium containing chemically defined supplements. Under these conditions, onset of cell process development was rapid, giving rise to extensive neurite networks. Three morphologically distinct cell types were apparent during the first week in vitro. Some cells retained a circular outline and failed to produce processes, while 50-60% of the cells developed as multipolar neurons showing a large cell body and several neurites. Approximately 90% of these cells reacted with an amacrine cell-specific monoclonal antibody. Some 30% of the cultured cells expressed phenotypic properties characteristic of rod photoreceptors, including a small cell body, an apical cilium, a short neurite with a spherule-like terminal body, and immunoreactivity with antibodies against opsin as well as a rod cell-specific monoclonal antibody. No further signs of outer segment differentiation were observed in these cells. Non-neuronal "flat" cells, which represented less than 0.5% of the total cell number, reacted with an antibody against the glial fibrillary acidic protein. The number of neurons and photoreceptors remained relatively stable during the first 4-7 days in vitro. During the second week in culture, however, there was specific degeneration of greater than 90% of the photoreceptor cells, while less than 20% of the multipolar neurons were similarly affected. Consequently, in addition to providing a system for studying the differentiation of retinal neurons and photoreceptors, the specific degeneration of photoreceptors in these mouse retinal cell cultures makes this system ideal for investigating factors influencing photoreceptor survival.  相似文献   

16.
Kang QY  Liu Y  Chen XL  Zhao JJ  Zhang PB  Li J  Luo Y  Qian YH  Song TS 《中华眼科杂志》2006,42(10):901-907
目的比较人视网膜祖细胞和脑神经干细胞的体外分化潜能。方法分离8-12周人胎儿神经视网膜和脑皮质、纹状体神经干细胞,进行无血清体外培养;采用光镜和免疫细胞化学或荧光免疫细胞化学染色方法,分别观察在无血清和10%胎牛血清培养条件下,两种来源的神经干细胞分化后的细胞特性。结果两种来源的神经干细胞,均能在体外有或无血清培养条件下增殖并分化。视网膜祖细胞不但表达视网膜祖细胞标志物Pax-6,也可表达神经干细胞标志物.巢蛋白(Nestin)、成熟神经元标志物-微管相关蛋白2(Map2)、星形胶质细胞标志物-胶质纤维酸性蛋白(GFAP)、节细胞标志物Thy-1和视杆细胞标志物视紫红质(Rhodopsin);脑神经干细胞也能表达这些特异性细胞标志物。血清诱导分化时,视网膜祖细胞较难贴壁,贴壁细胞球伸出少而短的突起,单个细胞形态不清;而脑神经干细胞球易贴壁并伸出较长突起交织成网,大量细胞从细胞球中沿突起徙出,单个细胞形态清晰。结论人胎儿视网膜祖细胞和脑神经干细胞体外培养均具有向神经元、胶质细胞及视网膜终末细胞分化的能力;两种干细胞在进行血清诱导分化时,细胞的贴壁、迁移能力及分化后的细胞形态均存在差异。(中华腠科杂志,2006,42:901.907)  相似文献   

17.
PURPOSE: To investigate whether conditioned medium from embryonic rat retinas can induce differentiation of adult rat hippocampus-derived neural stem cells (AHSCs) into neurons and glia in vitro. METHODS: AHSCs were cultured in 3 types of media: standard culture medium, conditioned medium from embryonic rat retina, and standard culture medium with retinoic acid. Neuronal and glial differentiation of the cultured cells was assessed by cell growth analysis, flow cytometric analysis, immunofluorescent staining, and RT-PCR analysis. RESULTS: Cells cultured in the standard medium showed very little neuronal and glial differentiation. The cells cultured in the conditioned medium and the medium with retinoic acid showed neuronal morphology and growth inhibition. They also expressed mature neuronal markers and glial markers. In addition, the cells cultured in the conditioned medium expressed Thy-1, HPC-1, and calbindin, which were not found in the previous studies with postnatal retinas in vivo. Those cultured in the medium with retinoic acid expressed HPC-1 and calbindin, but not Thy-1. CONCLUSIONS: Conditioned medium from embryonic rat retina contains factors that induce neuronal and glial cell differentiation of AHSCs, and promote up-regulation of some types of retinal cell markers.  相似文献   

18.
目的 探讨视网膜神经细胞培养的上清液对胚胎干细胞(embryonic stem cells, ES)体外分化的诱导作用。 方法 收集SD大鼠视网膜神经细胞培养上清液,抽滤后按2∶3比例与DMEM培养液混合,用该混合液进行ES 细胞的诱导分化,每天倒置相差显微镜观察ES细胞的生长及分化情况,对诱导分化后的细胞进行神经丝蛋白(nellcofilament protein,NFP)免疫组织化学检查。 结果 加入了视网膜神经细胞培养上清液的ES细胞生长出类似神经细胞突起样结构,NFP免疫组织化学染色阳性。 结论 SD大鼠视网膜神经细胞培养的上清液具有诱导ES细胞向神经细胞分化的作用。 (中华眼底病杂志, 2002, 18: 134-136)  相似文献   

19.
背景 人视网膜胶质细胞在视网膜增生性疾病的研究中有重要作用,以往研究者已成功地培养了人视网膜胶质细胞,但方法学有待进一步改进以达到细胞收获量更大的目的. 目的 建立快速、收获量大且纯度高的视网膜胶质细胞的培养方法,对目标细胞的抗原表达特点进行分析. 方法 取正常人角膜移植供体眼球分离视网膜组织,采用质量分数2%胰蛋白酶和质量分数0.133%胶原酶Ⅵ用二步法消化获取人视网膜胶质细胞,用含质量分数10%胎牛血清的人内皮细胞培养液,其中添加内皮细胞生长因子(β-ECGF)和肝素钠,对分离的细胞进行体外培养,培养皿用纤维黏连蛋白(FN)包被以促进人视网膜胶质细胞贴壁.观察收获的目标细胞的形态特征,采用活体显微镜下形态学观察、常规组织学观察法观察目标细胞的生长,同时采用免疫组织化学法检测胶质纤维酸性蛋白(GFAP)、波形蛋白(Vimentin)、神经元特异性烯醇化酶(NSE)、S-100、CD34、Ⅷ因子在细胞中的表达以鉴定目标细胞. 结果 应用胰蛋白酶、胶原酶二步消化法可成功获取人视网膜胶质细胞,原代培养的细胞72 h贴壁,第9~10天细胞达到融合状态呈花瓣状;常规组织学观察显示细胞核呈鲜亮蓝色,细胞质(盘膜)呈淡红色,培养细胞GFAP、Vimentin呈强阳性表达,NSE、S100、CD34、Ⅷ因子相关抗原表达呈阴性反应. 结论 应用胰蛋白酶、胶原蛋白酶消化法以及利用10%胎牛血清的人内皮细胞培养基,添加生长因子和肝素钠,并用FN包被培养皿进行体外培养可达到快速、大量分离和纯化人视网膜胶质细胞的目的,鉴定结果提示培养的目标细胞为人视网膜胶质细胞,其形态与以往报道的有所不同,具体特点尚需进一步研究.  相似文献   

20.
目的:在前人建立的方法上优化SD大鼠视网膜神经细胞体外培养的技术和方法,为后续研究提供实验基础。方法:使用胰酶消化法分离新生1~3dSD大鼠视网膜神经细胞,以DMEM/F12为培养基体外培养,免疫组织化学染色的方法进行鉴定。结果:观察光镜下培养的细胞贴壁生长,部分细胞伸出突起,且有些突起相互连接。免疫细胞化学染色显示,培养的细胞大多数抗神经元特异性烯醇化酶(neuron specific enolase,NSE)抗体反应阳性。结论:视网膜神经细胞体外培养成功为进一步进行视网膜疾病的研究创造了条件。  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