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1.
目的 观察牙龈卟啉单胞菌(P.gingivalis)W83和ATCC33277株侵入在单核细胞对内皮细胞黏附作用中的影响,及在内皮细胞细胞间黏附分子l(ICAM-1)转录和翻译中的作用. 方法 建立体外P.gingivalis侵入内皮细胞模型,孟加拉玫瑰红活细胞染色法测定P.gingivalis侵入前后单核细胞对内皮细胞黏附的变化;RT-PCR和mRNA比色定量法检测内皮细胞ICAM-1基因表达;West-ern blot检测ICAM-1蛋白水平的变化. 结果 P.gingivalis W83和ATCC33277株侵入可增加单核细胞对内皮细胞的黏附,抗ICAM-1抗体部分抑制P.gingivalis侵入介导的单核细胞对内皮细胞黏附增加;P.gingivalis侵入上调内皮细胞ICAM-l基因和蛋白的表达,W83诱导单核细胞对内皮细胞黏附增强及内皮细胞ICAM-1表达的能力强于ATCC33277. 结论 ICAM-1在P.gingivalis介导的单核细胞对内皮细胞黏附增强过程中起部分作用,P.gingivalis侵入内皮细胞诱导ICAM-1表达可能是其诱发动脉粥样硬化疾病的机制之一.  相似文献   

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AIMS: Neoangiogenesis is accompanied by an increase in endothelial surface, which can support infiltration by immune cells depending on adhesion molecule expression. Therefore, the expression of cell adhesion molecules on microvessels and epithelial cells was analysed in renal cell carcinomas as compared to tumour-free tissue. METHODS AND RESULTS: PECAM-1, CD34, ICAM-1, VCAM-1, VLA-4, P- and E-selectin, the macrophage antigens Ki-M1P and Mac-1, and lymphocyte function antigen LFA-1 were identified immunohistochemically. VCAM-1, ICAM-1, and E-selectin were equally or less expressed, whereas P-selectin was increased on microvessels in tumour tissue. The density of VCAM-1-positive tumour microvessels correlated positively with an advanced tumour stage and E- and P-selectin-positive tumour microvessels with the amount of associated macrophages. The expression of ICAM-1 and VCAM-1 on neoplastic epithelia correlated with an increased density of macrophages and a minor degree of tumour differentiation. CONCLUSIONS: The positive correlation of macrophage infiltration and expression of cell adhesion molecules on tumour microvessels and epithelia with minor tumour differentiation and an advanced stage indicates that adhesion molecule expression is not associated with an effective antitumour function of macrophages  相似文献   

4.
Immunosuppression correlates with the development and recurrence of cancer. Mycophenolate mofetil (MMF) has been shown to reduce adhesion molecule expression and leucocyte recruitment into the donor organ. We have hypothesized that MMF might also prevent receptor-dependent tumour dissemination. Therefore, we have investigated the effects of MMF on tumour cell adhesion to human umbilical vein endothelial cells (HUVEC) and compared them with the effects on T cell-endothelial cell interactions. Influence of MMF on cellular adhesion to HUVEC was analysed using isolated CD4+ and CD8+ T cells, or WiDr colon adenocarcinoma cells as the model tumour. HUVEC receptors ICAM-1, VCAM-1, E-selectin and P-selectin were detected by flow cytometry, Western blot or Northern blot analysis. Binding activity of T cells or WiDr cells in the presence of MMF were measured using immobilized receptor globulin chimeras. MMF potently blocked both T cell and WiDr cell binding to endothelium by 80%. Surface expression of the endothelial cell receptors was reduced by MMF in a dose-dependent manner. E-selectin mRNA was concurrently reduced with a maximum effect at 1 microm. Interestingly, MMF acted differently on T cells and WiDr cells. Maximum efficacy of MMF was reached at 10 and 1 microm, respectively. Furthermore, MMF specifically suppressed T cell attachment to ICAM-1, VCAM-1 and P-selectin. In contrast, MMF prevented WiDr cell attachment to E-selectin. In conclusion, our data reveal distinct effects of MMF on both T cell adhesion and tumour cell adhesion to endothelial cells. This suggests that MMF not only interferes with the invasion of alloactivated T cells, but might also be of value in managing post-transplantation malignancy.  相似文献   

5.
The accumulation of leukocytic infiltrates in perivascular tissues is a key step in the pathogenesis of Lyme disease, a chronic inflammatory disorder caused by Borrelia burgdorferi. During an inflammatory response, endothelial cell adhesion molecules mediate the attachment of circulating leukocytes to the blood vessel wall and their subsequent extravasation into perivascular tissues. Using cultured human umbilical vein endothelial cells (HUVEC) in a whole-cell enzyme-linked immunosorbent assay, we demonstrated that B. burgdorferi activated endothelium in a dose- and time-dependent fashion as measured by upregulation of the adhesion molecules E-selectin, vascular cell adhesion molecule 1 (VCAM-1), and intercellular adhesion molecule 1 (ICAM-1). As few as one spirochete per endothelial cell stimulated increased expression of these molecules. Expression of E-selectin peaked after spirochetes and HUVEC were coincubated for 4 h and returned to near-basal levels by 24 h. In contrast, expression of VCAM-1 and ICAM-1 peaked at 12 h and remained elevated at 24 h. HUVEC monolayers cultured on acellular amniotic tissue were used to investigate the consequences of endothelial cell activation by spirochetes. After incubation of HUVEC-amnion cultures with B. burgdorferi, subsequently added neutrophils migrated across the endothelial monolayers. This process was mediated by E-selectin and by CD11/CD18 leukocytic integrins. The extent of migration depended on both the number of spirochetes used to stimulate the HUVEC and the length of the coincubation period. These results raise the possibility that B. burgdorferi induces a host inflammatory response and accompanying perivascular damage through activation of vascular endothelium.  相似文献   

6.
The expression of adhesion molecules on vascular endothelial cells determines the pattern of migration and extravasation of leucocytes in inflammation and immunity. Here we show that costimulation with CD40 ligand (CD40L) and interleukin (IL)-4 (or IL-13) gives rise to a unique pattern of adhesion molecule expression by human umbilical vein endothelial cells (HUVEC). CD40 ligation alone enhanced expression of vascular cell adhesion molecule-1 (VCAM-1), intracellular adhesion molecule-1 (ICAM-1) and E-selectin whereas IL-4 and IL-13 increased expression of VCAM-1 and P-selectin but not ICAM-1 or E-selectin. When IL-4 and CD40L were combined there was an additional increase of both VCAM-1 and P-selectin, but ICAM-1 and E-selectin were both inhibited. The combined effects of IL-4 and CD40L signalling were not the result of altered response kinetics, enhanced sensitivity of the endothelium, or increased expression of CD40 or the IL-4 receptor. The rise in VCAM-1 expression induced by combined IL-4 and CD40L stimulation was slower and more sustained than with tumour necrosis factor-alpha (TNF-alpha) and occurred only on a subset (75-80%) of the endothelial cell population compared to 100% with TNF-alpha. Costimulation with IL-4 and CD40L increased adhesion of T cells and B cells above levels obtained with either signal alone, but decreased adhesion of neutrophils. Furthermore, CD40 and IL-4 synergistically increased IL-6 but decreased IL-8 production by HUVEC. These results show that interactions between IL-4 and CD40 on endothelial cells give rise to specific patterns of adhesion molecule expression and cytokine production that may have important implications for lymphocyte and neutrophil migration and function at sites of inflammation.  相似文献   

7.
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   

8.
OBJECTIVES: E7 is one of the oncoproteins encoded by human papillomavirus-16 (HPV-16), the major etiologic factor responsible for cervical cancer. Human papillomavirus-16-E7 expressed by human uterine cervix carcinoma cells is also released in the extracellular compartment where it induces immune suppression. We investigated whether E7 was also responsible for the enhanced endothelial adhesiveness required in cancer progression. STUDY DESIGN/METHODS: We treated cervical microvascular endothelial cells (CrMVEn) and human umbilical vein endothelial cells (HUVEC) with E7, tumor necrosis factor-alpha (TNF-alpha), and hydrogen peroxide (H2O2) and measured the expression of E-selectin, intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) by fluorescent-activated cell sorter analysis. RESULTS: E7 strongly induced the expression of E-selectin, ICAM-1, and VCAM-1 in CrMVEn, but not in HUVEC. Tumor necrosis factor-alpha further increased the endothelial expression of adhesion molecules in CrMVEn. Hydrogen peroxide pre-treatment resulted in an enhanced ICAM-1 and a decreased E-selectin and VCAM-1 expression. We also show indirect effects when endothelial cells were stimulated with the supernatant of E7-pretreated macrophages. CONCLUSIONS: These results show that HPV-16-E7 oncoprotein strongly induces adhesion molecules expression in organ-specific endothelial cells.  相似文献   

9.
流体切应力对内皮细胞粘附分子表达的影响   总被引:2,自引:0,他引:2  
在动脉粥样硬化(Atherosclerosis,As)的发生发展中各种白细胞,包括单核细胞对内皮细胞的粘附可能起着较为重要的作用。在体内,血流切应力对内皮细胞的形态和功能有重要影响。为了阐明流体切应力对内皮细胞表面粘附分子表达的影响,本文研究了流体切应力(2.23~6.08dyne/cm  相似文献   

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Stimulation of cultured human umbilical vein endothelial cells (HUVEC) with lipopolysaccharide (LPS) induces adherences for human promyelocytic cell line HL60. Adherence of HL60 cells to HUVEC stimulated with LPS for 4h was completely inhibited by pretreatment with SJC13, an azaindolidine derivative. The mechanism whereby SJC13 inhibits the adhesiveness of HUVEC was investigated. Pretreatment of SJC13 inhibited LPS-induced expression of E-selectin and vascular cell adhesion molecule-1 (VCAM-1), but not intercellular adhesion molecule-1 (ICAM-1), in HUVEC, determined by flow cytometry and cellular enzyme-linked immunosorbent assay (cell-ELISA). The inhibitory activity was concentration dependent between 62.5 and 1,000 g/ml. SJC13 also selectively inhibited LPS-induced increases in E-selectin and VACM-1 mRNAs, indicating that the action of SJC13 is to inhibit synthesis of these molecules. These data demonstrate that SJC13 is capable of selectively inhibiting the expression of E-selectin and VCAM-1, but not ICAM-1, in endothelial cells.accepted by I. Ahnfelt-Rønne  相似文献   

12.
T Okada  H Sagara  Y Nakano  T Hiyama  T Fukuda 《Arerugī》1999,48(12):1322-1330
The accumulation of eosinophils in the airway is one of the characteristics seen in patients with bronchial asthma. One of the newly developed anti-asthma drugs (controller), nedocromil sodium (nedocromil) is known to suppress the influx of eosinophils into allergic lesions. However, little is known about this mechanism. Therefore, in this report we investigated the effects of nedocromil on Mac-1 expression on PAF-stimulated eosinophils, and adhesion molecule expression on endothelial cells stimulated by either IL-1 beta or IL-4. We also investigated the eosinophil chemotaxis. A significant suppression of the Mac-1 expression on PAF-induced eosinophils was observed at both concentrations of 10(-5) and 10(-7) M of nedocromil. The expression of adhesion molecules, particularly ICAM-1 and E-selectin, on IL-1 beta-stimulated human umbilical vascular endothelial cells (HUVEC) was significantly suppressed at these concentrations, whereas the VCAM-1 expression was not changed. No significant suppression of VCAM-1 expression on IL-4-stimulated HUVEC was observed, although there was a tendency of suppression at these concentrations. On the other hand, the expression of the E-selectin molecule was significantly suppressed by nedocromil even under resting (non-stimulated) condition. PAF-induced eosinophil chemotactic activities were also suppressed at these concentrations in a dose-dependent manner. These results suggested that nedocromil suppressed the influx of eosinophils to inflammatory lesions by inhibiting not only the expression of the Mac-1 on eosinophils and of E-selectin and ICAM-1 molecules on HUVEC, but also the eosinophil chemotactic activities.  相似文献   

13.
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   

14.
Bacteroides thetaiotaomicron, a Gram-negative anaerobic rod belonging to the Bacteroides fragilis group (BFG), is involved in many systemic and local, most frequently suppurative infections in man. The cell envelope of these rods is composed of two carbohydrate-containing antigens: lipopolysaccharide (LPS) and capsular polysaccharide (CPS). Adhesion molecules ICAM-1, VCAM-1 and E-selectin (ELAM-1) are induced on the endothelial cells by mediators of inflammation. The aim of this study was to assay the ability of B. thetaiotaomicron surface antigens to induce adhesion molecule expression on the endothelial cells. The influence of LPS and CPS on the expression of adhesion molecules on HMEC-1 cell line was examined in an ELISA test. ELISA was performed with monoclonal mouse anti-human: ICAM-1, VCAM-1 and E-selectin antibodies of the IgG class. B. thetaiotaomicron lipopolysaccharides revealed the ability to induce ICAM-1, VCAM-1 and E-selectin expression on the endothelial cells. Their activities were similar, but lower than the activity of Eschericha coli LPS. ICAM-1 was the most stimulated adhesion molecule. The strongest activation by LPS was achieved at the concentrations of 10.0 and 1.0 micrograms/ml. The ability of capsular polysaccharide to induce the expression of adhesion molecules was considerably weaker.  相似文献   

15.
EA-hy-926 is a cell line produced by hybridizing human umbilical vein endothelial cells (HUVEC) and the epithelial cell line A549. To establish whether EA-hy-926 could be used as a model for endothelial cells (EC) in leucocyte-EC adhesion interactions, the effect of interleukin-4 (IL-4), tumour necrosis factor (TNF) or interferon-γ (IFN) stimulation on their adhesiveness and expression of E-selectin, vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) was compared with that of HUVEC and A549. Although HUVEC exhibited increased adhesiveness and adhesion molecule expression with IL-4, TNF or IFN, EA-hy-926 exhibited these responses only with TNF. CD11/CD 18-dependent binding accounted for a significant component of basal binding to HUVEC and EA-hy-926, but did not account for the increased binding of T cells, JY, J6, ICH-BJ or ICH-KM cell lines to TNF-stimulated monolayers. At least part of the CD1l/CD18-independent adhesion was attributable to VCAM-1 induction on HUVFC and FA-hy-926. TNF-stimulation also induced F-selectin expression on EA-hy-926 and HUVEC and an accompanying increase in neutrophil (PMN) binding. The EA-hy-926 cells used in this study, therefore, showed responses similar to HUVEC when stimulated with TNF but not when stimulated with IL-4 or IFN.  相似文献   

16.
目的:观察轻度修饰LDL(MM-LDL)对培养人脐静脉内皮细胞(HUVEC)与人类单核细胞系U937粘附功能及其表面粘附分子表达的影响。方法:利用计数法观察经MM-LDL作用的HUVEC与U937细胞的粘附率;用ELISA方法检测MM-LDL作用后HUVEC膜表面粘附分子血管细胞粘附分子-1(VCAM-1)、细胞间粘附分子-1(ICAM-1)及P选择素(P-selectin)的表达。结果:MM-LDL(75mg/L)作用HUVEC4h后,其对U937细胞粘附率明显增加(P<0.01),HUVEC膜表面未见VCAM-1,ICAM-1,P-selectin表达上调,作为阳性对照重组肿瘤坏死因子α(rTNFα)5.0μg/L可显著诱导以上3种粘附分子表达。延长MM-LDL与HUVEC作用时间至18h可诱导产生P-selectin表达,对VCAM-1表达无影响。结论:MM-LDL诱导的HUVEC与U937粘附不是通过ICAM-1、VCAM-1介导的,P-selectin可能起一定的作用。  相似文献   

17.
BACKGROUND: Allergic rhinitis (AR) and asthma are characterized by means of a similar inflammatory process in which eosinophils are important effector cells. The migration of eosinophils from the blood into the tissues is dependent on adhesion molecules. OBJECTIVE: To analyze the aspects of nasobronchial cross-talk, we studied the expression of adhesion molecules in nasal and bronchial mucosa after nasal allergen provocation (NP). METHODS: Nine nonasthmatic subjects with seasonal AR and 9 healthy control subjects underwent NP out of season. Bronchial and nasal biopsy specimens were taken before (T(0)) and 24 hours after NP (T(24)). Mucosal sections were analyzed for the presence of eosinophils, IL-5, eotaxin, intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), E-selectin, and human endothelium (CD31). RESULTS: At T(24), an influx of eosinophils was detected in nasal epithelium (P =.01) and lamina propria (P <.01), as well as in bronchial epithelium (P =.05) and lamina propria (P <.05), of the patients with AR. At T(24), increased expression of ICAM-1, as well as increased percentages of ICAM-1+, VCAM-1+, and E-selectin+ vessels, were seen in nasal and bronchial tissue of patients with AR. The number of mucosal eosinophils correlated with the local expression of ICAM-1, E-selectin, and VCAM-1 in patients with AR. CONCLUSION: This study shows that NP in patients with AR results in generalized airway inflammation through upregulation of adhesion molecules.  相似文献   

18.
A fundamental feature of inflammation includes angiogenesis, adhesion of leukocytes to vascular endothelium, and entry of leukocytes into inflamed tissues. Recent studies have suggested that angiogenesis and cellular adhesion may be mutually linked processes. Both basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) have been shown to facilitate angiogenesis. However, their roles in the expression of adhesion molecules on the endothelial cells have not been clarified. The current studies therefore examined the effect of bFGF and VEGF on the expression of vascular cell adhesion molecule-1 (VCAM-1) on human umbilical vein endothelial cells (HUVEC) stimulated with tumor necrosis factor alpha (TNF-alpha). HUVEC (1 x 10(4)/well) were incubated in a 96 well microtiter plate with culture medium containing endothelial cell growth supplement (ECGS) for 24 h. After the incubation, culture medium was replaced by ECGS free culture medium with or without TNF-alpha (10 ng/ml), bFGF (10 ng/ml) and VEGF (10 ng/ml), and the culture was further carried out for additional 24 h. The expression of VCAM-1, E-selectin, and intercellular adhesion molecule-1 (ICAM-1) was measured by cell ELISA and the proliferation of HUVEC was measured by MTT colorimetric assay. Soluble VCAM-1 (sVCAM-1) in the supernatants were assessed by ELISA. Although, both bFGF and VEGF supported the proliferation of HUVEC, bFGF, but not VEGF, selectively suppressed the expression of VCAM-1 on HUVEC stimulated with TNF-alpha. The expression of ICAM-1 and E-selectin induced by TNF-alpha was not inhibited by either bFGF or VEGF. In addition, bFGF also decreased the levels of sVCAM-1 in the supernatants of TNF-alpha stimulated HUVEC. The data indicate that bFGF, but not VEGF, suppresses the production of VCAM-1 by HUVEC under stimulation with TNF-alpha. These results therefore suggest that angiogenic cytokines bFGF and VEGF play different roles in the regulation of the expression of adhesion molecules on endothelial cells under inflammation.  相似文献   

19.
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   

20.
Pulmonary surfactant given to infants and adults with respiratory failure is metabolized and recycled to a large extent. A small proportion also enters the circulation in cases of increased permeability of the alveolar-capillary membrane. We therefore investigated whether exogenous surfactants such as a natural bovine (natSF) or a synthetic (synSF) preparation had an impact on inflammatory conditions involving the adhesion of neutrophils to endothelial cells. Human umbilical cord vein endothelial cells (HUVEC) were plated on coverslips until confluence, activated by tumor necrosis factor-alpha and incubated with or without surfactant in the media. Human neutrophils passed the HUVEC layer in a flow chamber and interactions were visualized using a video microscope. To test if surfactant affected the expression of cell adhesion molecules, RT-PCR analyses were performed for E-selectin, vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1). Using concentrations between 50 and 300 microg/ml of surfactant in the pre-incubation media the number of adherent neutrophils increased by 10-20% at the higher concentration of the natSF (*P < 0.05) whereas the synSF had no effect. Increased neutrophil adhesion was associated with a significant up-regulation of mRNA levels for E-selectin and VCAM-1; mRNA levels for ICAM-1, however, were not affected by the presence of surfactant. These observations indicate that natSF but not synSF might have pro-inflammatory effects when higher amounts of the exogenous dose reach the circulation. This might be explained by different fatty acid profiles, e.g. the presence of arachidonic acid in the natSF or higher concentrations of surfactant-associated protein-C in the synSF.  相似文献   

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