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 15 毫秒
1.
The concentration of medullasin, an elastase-like serine proteinase, in gingival crevicular fluid (GCF) from chronic adult periodontitis patients and experimental gingivitis subjects was determined by the highly sensitive immunoassay method. In periodontitis patients, the medullasin content increased with increase of the GCF volume and then attained a maximum value at a relatively mildly inflamed stage. The value was maintained through more serious stages of disease activity. However, the medullasin content was independent of the probing depth. The medullasin content of the patients was markedly decreased after periodontal treatment, indicating that the enzyme participates in the development of the chronic periodontitis. Large amounts of medullasin were also detected in GCF from experimental gingivitis subjects, although it was not detected by the activity measurements. There was a rapid increase in the medullasin content during the 4-day period after abstention from oral hygiene measures, which corresponded to those of severely inflamed periodontitis patients. The peak value decreased up to the 7th-d followed by a gradual increase during the 21-d experimental period. The increased medullasin level rapidly decreased following resumption of oral hygiene measures. The results suggest that medullasin plays important roles both in the defence mechanism against the gingival inflammation and in the development of the acute inflammation.  相似文献   

2.
Abstract. Phylloquinone is a lipid soluble vitamin which is an absolute growth requirement for black-pigmented anaerobes, many of which are implicated in the aetiology of periodontal diseases. This cross-sectional study aimed to detect the levels of phylloquinone in GCF from healthy and diseased sites in subjects with adult periodontitis, in order to investigate further its potential role in the disease process. The sample consisted of eighteen patients with adult periodontitis. Periodontal probing depths, attachment levels and gingival indices were recorded from one healthy and one diseased site in each subject. GCF was sampled and the amount of phylloquinone in each sample was determined using reverse-phase high performance liquid chromatography coupled to electrochemical detection. The mean amount of phylloquinone in accumulated GCF from diseased sites was 406 pg/site and 80 pg/site from healthy sites ( p =0.013). When the amounts of phylloquinone in GCF were expressed as concentrations the values were 228 ng/ml and 3350 ng/ml for diseased and healthy sites respectively ( p =0.084). These findings suggest the levels of phylloquinone in GCF differs in periodontal health and disease in subjects with adult periodontitis. The total phylloquinone at diseased sites may provide the nutritional requirements favouring the growth of black-pigmented anaerobes.  相似文献   

3.
Background, aims: This study presents the first evidence on the presence of the chemokine RANTES in the gingival fluid crevicular (GCF) of patients with periodontitis. RANTES is a chemokine that selectively attracts and activates macrophages and lymphocytes. Leucocytes play a critical rôle in the host response to the subgingival microflora. Method: In this study, the presence de RANTES in GCF was determined in samples obtained from adult patients with periodontitis and from control subjects with clinically healthy gingiva. GCF was collected from different probing depths (<3 mm, 4–6 mm, >6 mm) (n=72); and active (n=12) and inactive sites (n=12). An active site was defined as attachment loss >2 mm, as determined by sequential probing and the tolerance method. GFC was collected for 30 s using Periopaper® strips, and RANTES was quantified by ELISA. Results: The presence of RANTES was detected exclusively in the group of patients with periodontitis, presenting a total amount of 40.43±16 pg and a concentration 67.80±41 pg/μl. RANTES concentration was significantly higher in probing depth <3 mm than in probing depth >6 mm (87.24 versus 51.87, p=0.014). Total amount and concentration in the GCF samples from active sites were higher that in inactive sites (p>0.05). Conclusions: The finding that RANTES is found only in patients with periodontitis, may represent a general feature of chronic inflammatory in periodontal diseases. Finally, RANTES may be implicated in the biological mechanisms underlying the pathogenesis and progression of periodontal disease.  相似文献   

4.
目的:探讨龈沟液中乳酸脱氢酶(LDH)水平对于慢性成人牙周炎患者诊断及预后观察的意义。方法:酶动力学方法。结果:患病部位和健康部位龈沟液中LDH水平有非常显著差异(P〈0.001)。探诊深度和龈沟液中LDH水平呈正相关(P〈0.05)。附着丧失水平和龈沟液中LDH水平呈正相关(P〈0.05)。结论:龈沟液中LDH水平对于慢性成人牙周炎的诊断和疗效监测具有一定的临床意义。  相似文献   

5.
BACKGROUND: This study aimed to determine the relationships among interleukin (IL)-8 and granulocyte elastase levels in gingival crevicular fluid (GCF) and the concomitant presence of periodontopathogens in untreated adult periodontitis. METHODS: GCF and subgingival plaque samples were collected from 16 patients with untreated adult periodontitis and 10 healthy control subjects. IL-8 levels were determined by enzyme-linked immunosorbent assay (ELISA). Granulocyte elastase was analyzed with a neutrophilic granulocyte-specific, low molecular weight and chromogenic substrate, L-pyroglutamyl-L-prolyl-L-valine-p-nitroanilide, and the maximal rate of elastase activity (MR-EA) was calculated. Five DNA probes were used to detect the presence of A. actinomycetemcomitans (A.a.), B. forsythus (B.f.), P. gingivalis (P.g.), P. intermedia (P.i.), and T. denticola (T.d.). RESULTS: Lower IL-8 concentrations and higher granulocyte elastase activities were found in patients than in healthy controls as well as in diseased conditions co-infected with B.f., P.g., P.i., and T.d. as compared to healthy conditions without the target species (P <0.05). IL-8 concentrations were positively correlated with MR-EA levels in the periodontitis conditions co-infected with B.f., P.g., P.i., and T.d. (P <0.05). A wide range of IL-8 concentrations was found among 15 patients when the periodontitis condition was characterized by co-infection with B.f., P.g., P.i., and T.d. MR-EA levels in the high IL-8 group of subjects were significantly higher than those in the low IL-8 group of subjects (P <0.01). CONCLUSIONS: The present study shows that the local host-bacteria interactions in untreated periodontitis are diverse in terms of the intensity of inflammatory responses measured by IL-8-related granulocyte elastase activity in GCF. This might reflect different phases of the inflammatory response due to shifts in host-bacteria interactions and therefore be indicative of a range of periodontal disease activity levels.  相似文献   

6.
Background: Interleukin (IL)-1 is closely related to the initiation and progression of periodontal disease. IL-1 levels in the gingival crevicular fluid (GCF) of subjects with periodontitis are higher than those in periodontally healthy controls, and the levels of IL-1 correlate with disease severity. However, soluble IL-1 receptor type II (sIL-1RII), which acts as a decoy receptor for IL-1s, has not been investigated in detail in periodontal disease. The purpose of this study was to measure sIL-1RII levels in the GCF of subjects with chronic or aggressive periodontitis; the correlation between the sIL-1RII levels in GCF and clinical parameters also was examined. Methods: IL-1beta and sIL-1RII were measured in 64 GCF samples collected from 47 subjects with chronic periodontitis (CP) and 17 subjects with aggressive periodontitis (AgP). The clinical characteristics of each site were recorded at the time of GCF sampling. IL-1beta and sIL-1RII were measured by specific non-cross-reactive enzyme-linked immunosorbent assay. Results: The disease severity was comparable in CP and AgP. IL-1beta was detected in 98% of CP GCF samples and 88% of AgP GCF samples. sIL-1RII was detected in 55% of CP GCF samples and 35% of AgP GCF samples. However, the concentrations of IL-beta and sIL-1RII detected in GCF from subjects with CP or AgP were similar. Conclusion: sIL-1RII was detected more often in CP GCF than in AgP GCF, and there was no correlation between GCF sIL-1RII concentration and clinical parameters.  相似文献   

7.
8.
BACKGROUND: The use of antibiotics as an adjunctive therapy in the treatment of periodontal diseases is of special interest to dental practitioners. In addition to using an appropriate antibacterial agent, clinicians may find it useful to determine the local and systemic concentrations of antibiotics in infected periodontal sites to reduce the levels of bacteria. The purpose of this study was to determine the serum and gingival crevicular fluid, or GCF, concentrations of systemic ciprofloxacin in patients with periodontitis. METHODS: Ten subjects with chronic periodontitis received ciprofloxacin (500 milligrams) twice daily for five days. The authors collected GCF and serum samples immediately after administering the first dose (baseline = 0 hours) and at consecutive time points. The orifice method was used for GCF sampling, and 5 milliliters of venous blood was drawn for serum analysis. The authors used high-performance liquid chromatography to determine ciprofloxacin concentrations in GCF and serum. RESULTS: The authors found that ciprofloxacin concentrations in GCF were significantly higher than concentrations in serum at two, four, seven, 24 and 120 hours. Ciprofloxacin reached the maximum concentration, or Cmax (3.72 micrograms/ mL), in GCF two hours after the initial dose was administered. The concentration decreased to 2.06 microg/mL 24 hours after the initial administration of the drug. Serum Cmax was 2.58 microg/mL at 1.5 hours, and the concentration decreased to 0.26 microg/mL at 24 hours. CONCLUSION: The results of this clinical study show that ciprofloxacin is found in GCF and its concentration in GCF is significantly higher than that in serum. CLINICAL IMPLICATIONS: Ciprofloxacin may be useful in treating patients with periodontitis because it reaches higher concentrations in GCF than in serum.  相似文献   

9.
Cathepsin G in gingival tissue and crevicular fluid in adult periodontitis   总被引:1,自引:0,他引:1  
Abstract The presence, localization and activities of cathepsin G in gingival tissue specimens and crevicular fluid (GCF) from 9 adult periodontitis patients and 6 controls with clinically healthy periodontium were studied by use of avidin-biotin-peroxidase complex method. Western and dot blotting, and spectrophotometric activity assay. In contrast to healthy gingival tissue specimens, gingival tissue specimens collected from adult periodontitis patients contained inflammatory cells in lamina propria, beneath the oral sulcular epithelium, 10–50% of which were cathepsin G positive polymorphonuclear neutrophilic leukocytes (PMNs) and monocyte/macrophage-like cells. Cathepsin G activities were increased in adult periodontitis GCF when compared to periodontally healthy controls' GCF (p>0.05). In adult periodontitis GCF, Western blotting disclosed free cathepsin G but also clear complexes of cathepsin G with its predominant endogenous inhibitor α1antichymotrypsin (α1-ACT). The present results demonstrate that part of the cathepsin G, despite the presence of increased concentrations of α1-ACT, was in an uncomplexed, free and functionally active form. Our results suggest that GCF cathepsin G reflects the disease process in adjacent inflamed gingiva and also increased host response to microbiota and/or dental plaque in the periodontitis lesions. Cathepsin G may contribute to periodontal tissue destruction directly and indirectly, via proteolytic activation of latent neutrophil procollagenase (promatrix metalloproteinase-8 [proMMP-8]).  相似文献   

10.
Abstract This study investigated levels of hyaluronan and chondroitin-4-sulphate in the crevicular fluid of patients with chronic adult periodontitis at diseased and healthy sites before and after treatment. The relationship between clinical diagnostic parameters and levels of glycosaminoglycans in gingival crevicular fluid were also analysed. Within each patient. 4 sites either mesial or distal and on single rooted teeth were classified as diseased or healthy using a modified gingival index, pocket depth and attachment loss. Crevicular fluid was collected from each site using glass micropipettes and analysed for glycosaminoglycan content by cellulose acetate electrophoresis. Significantly higher levels of chondroitin-4-sulphate were detected at diseased sites prior to treatment correlating with increased pocket depth or attachment levels. Following a period of treatment consisting of oral hygiene instruction and root planing, the patients were reassessed for their response to treatment by measuring the modified gingival index, pocket depth, attachment loss and levels of glycosaminoglycans. Analysis of glycosaminoglycan levels at diseased sites that demonstrated a poor response to treatment also demonstrated significantly higher levels of chondroitin-4-sulphate than those sites that responded well to treatment. Hyaluronan levels were less significantly associated with clinically succesful treatment. This study confirmed the use of the sulphated glycosaminoglycan chondroitin-4–sulphate as a potential diagnostic aid of periodontal tissue destruction; however, further longitudinal studies are required to assess their performance.  相似文献   

11.
OBJECTIVES: We set out to monitor gingival crevicular fluid prostaglandin E2 (GCF-PGE2) concentrations longitudinally in a cohort of subjects with chronic periodontitis, given that we had noted an unexplained trend for GCF-PGE2 concentrations to gradually increase in control groups and placebo populations in previously published clinical trials. MATERIAL AND METHODS: 41 adults with moderate-severe chronic periodontitis were recruited. GCF samples were collected from 8 test sites (with 5-8 mm probing depths and attachment loss) every 30 days for 150 days, and assayed for PGE2. Clinical measurements (probing depths, attachment levels, bleeding on probing) were recorded at days 0 and 150. RESULTS: A gradual and statistically significant increase in GCF-PGE2 concentrations was observed over the course of the study, from 40.3 ng/ml to 83.1 ng/ml (p<0.001). When data were expressed as absolute PGE2 content, a similar statistically significant increase from baseline to day 150 was observed (p<0.001). GCF volumes did not vary significantly during the study (p>0.05). Over the same time period, no statistically significant changes in clinical parameters were recorded, with the exception of mean probing depths, which decreased slightly from 5.73 mm to 5.51 mm (p<0.05). CONCLUSION: A trend for gradually increasing GCF-PGE2 concentrations in the absence of any clinical signs of disease progression was noted in a group of patients monitored longitudinally. We suggest that this phenomenon is to be expected in longitudinal clinical trials, and propose a new model for the role of PGE2 in the pathogenesis of periodontal destruction. We feel that if GCF mediators are to be monitored in clinical studies, then both concentrations and absolute mediator content should be calculated, and a standardised sampling protocol should be employed.  相似文献   

12.
AIM: To make an initial assessment of the periodontal diagnostic potential of immunoreactive matrix metalloproteinase-8 (MMP-8) in gingival crevicular fluid (GCF) by comparison with elastase activity which has previously been associated with disease severity and progression. METHODS: GCF was collected from molar and premolar sites of 16 chronic adult periodontitis patients before treatment and 13 of this group 2 weeks after scaling and root planing. Samples were analysed for MMP-8 by immunofluorometric assay and for elastase activity with a fluorogenic substrate. RESULTS: Mean patient clinical parameters and GCF enzyme totals both decreased significantly after treatment. Total MMP-8 levels and elastase activities generally correlated significantly with gingival and bleeding indices. For GCF concentrations, only MMP-8 showed a significant fall after treatment, and some significant correlations with clinical parameters. Amounts of the 2 enzymes correlated significantly with each other. CONCLUSIONS: Similarities between MMP-8 and elastase probably reflect the fact that both enzymes are associated mainly with neutrophils: MMP-8 levels may have fallen more after treatment because the assay, unlike that for elastase, would most likely not have detected much enzyme bound to alpha-macroglobulin. The immunoassay for MMP-8 is more specific and convenient than functional collagenase assays, and might be suitable for monitoring the periodontal condition.  相似文献   

13.
慢性成人牙周炎患者龈沟液谷胱甘肽过氧化物酶的测定   总被引:2,自引:0,他引:2  
目的 :证实龈沟液 (gingival crevicular fluid,GCF)中谷胱甘肽过氧化物酶 (glutathione peroxida.se,GPx)的存在 ,初步探讨其与牙周病的关系。方法 :选择 12名牙周健康者 (H组 )的 2 1个牙位点及 2 3名慢性成人牙周炎患者 (AP组 ) 4 4个牙位点用 DTNB显色法测定 GCF- GPx活性 ,并记录 AP组 GI、PD、AL。结果 :AP组 GCF- GPx活性〔(16 0 .0 7± 12 1.44 ) U〕明显低于 H组 (5 0 3.35± 30 4.36 ) (P<0 .0 0 1) ,AP组 GPx活性与 PD、AL 负相关 (r=- 0 .30 5 8,P<0 .0 5 r=- 0 .42 92 ,P<0 .0 5 )。结论 :GCF- GPx的存在间接提示 :牙周炎可能是局部自由基产生清除失衡的结果 ,牙周局部存在着抗氧化能力的下降。  相似文献   

14.
This study aimed to determine the association between the levels of granulocyte elastase and prostaglandin E2 (PGE2) in GCE and the concomitant presence of periodontopathogens in untreated adult periodontitis (AP). GCF and subgingival plaque were sampled by paper strips and paper points respectively, from various periodontal sites in 16 AP subjects. Granulocyte elastase activity in GCF was analyzed with a low molecular weight substrate specific for granulocyte elastase, pGluProVal-pNA, and the maximal rate of elastase activity (MR-EA, mAbs/min/site) was calculated. PGE2 levels in GCF were determined by radioimmunoassay. 5 species-specific DNA probes were used to detect the presence of A. actinomyceterncomitans (A.a., ATCC 43718), B. forsythus (B.f, ATCC 43037), P. gingivalis (P.g., ATCC 33277), P. intermedia (P.i., ATCC 33563), and T. denticola (T.d., ATCC 35405), with a sensitivity of 10(3) cells/paper point. No A.a. was detectable from all sites sampled. The predominant combination of species detected was B.f., P.g., P.i. & T.d. and it was significantly higher at periodontitis sites (68%) than at healthy (7%) or gingivitis sites (29%) (p<0.05). Overall, MR-EA values were strongly correlated with PGE2 levels (r=0.655, p<0.001), especially at these periodontitis sites co-infected by B.f., P.g., P.i. & T.d. (r=0.722, p<0.001). The periodontitis sites co-infected by the 4 species were observable from 15 subjects. These sites were sub-grouped into 8 subjects with a high MR-EA and 7 subjects with a low MR-EA. The PGE2 levels in the high MR-EA group were significantly higher than in the low MR-EA group (p<0.05). No significant differences in clinical or bacterial data were found between the two groups. While within the high MR-EA group, similar results were found between the paired periodontitis sites in each subject with highest and lowest MR-EA values. This study shows that the local host response to bacterial challenge in untreated periodontal pockets is diverse in terms of the intensity of inflammatory response measured by granulocyte elastase and PGE2 levels in GCE A more thorough evaluation of the risk for active periodontal disease may involve the combined approaches to the test of the dynamic bacteria-host relations.  相似文献   

15.
OBJECTIVE: Evidence reveals the role of reactive oxygen species (ROS) in many pathologies including periodontitis. Protein carbonylation is the most widely used biomarker for oxidative damage to proteins, and reflects cellular damage induced by ROS. In this study protein carbonyl (PC) levels in serum and gingival crevicular fluid (GCF) in patients with chronic periodontitis (CP) was evaluated. MATERIALS AND METHODS: Thirty-three patients with CP and 24 healthy controls were included in the study. Following the clinical measurements and samplings, total protein levels in serum and GCF were determined by Bradford method, and serum and GCF PC levels were measured by modified Levine method. RESULTS: PC levels in serum and GCF were significantly higher in the CP group compared to the control group (p<0.05). In all subjects, serum and GCF PC levels showed statistically significant positive correlations with all clinical parameters (p<0.05). CONCLUSIONS: The results suggest that both systemic and local/periodontal protein carbonylation increase in CP compared to health and that elevated levels of PCs may be a sign of oxidative damage in periodontitis and correlate well with the periodontal status.  相似文献   

16.
孙颖  孙卫斌  徐艳  陈武 《口腔医学》2007,27(1):18-20
目的比较吸烟与非吸烟牙周炎患者和健康人龈沟液中细胞外弹性蛋白酶EA-s和细胞内弹性蛋白酶(EA-p)水平的变化。方法选择慢性牙周炎患者41例,共146个探诊出血(BOP)、牙周袋探诊深度(PD)≥4mm、附着丧失(AL)≥2mm的牙周炎位点,将其分为吸烟组79个,非吸烟组67个。同时选择牙周健康者31人作为对照,共85个探诊不出血,牙龈指数(GI)≤1,PD≤3mm,AL≤1mm的位点,同样分为2组,吸烟组45个,非吸烟组40个。观察牙周治疗前、后牙周临床指标菌斑指数(PLI),GI,PD,AL,BOP和龈沟液中EA-s、EA-p水平的变化。结果牙周炎患者中,吸烟组的GI,AL和EA-s水平低于非吸烟组(P<0.05),其余指标差异无显著性(P>0.05),健康者的各项指标差异均无显著性(P>0.05)。无论是吸烟组还是不吸烟组,牙周炎患者的EA-s,EA-p水平均高于健康者(P<0.05)。结论吸烟会降低牙周炎患者龈沟液中EA-s水平,但对EA-p水平影响不大。吸烟对健康人EA水平无显著影响。  相似文献   

17.
Interleukin-1 beta (IL-1beta) is a potent bone-resorptive cytokine that also mediates soft-tissue destruction by stimulating prostaglandin production and inducing collagenase and other protease activity. The literature suggests that this substance may be an important mediator of attachment loss in human periodontitis, and indicates that IL-1beta may be useful for locating sites of periodontal disease activity. There is some evidence that IL-1beta is produced by cells of the periodontium, and that it can be detected in gingival crevicular fluid (GCF). Many factors are known to contribute to the destruction of periodontal tissue. One of the most important is immune deficiency in diabetes. The aim of this study was to measure and compare the concentration of IL-1beta in the GCF of patients with non-insulin-dependent diabetes mellitus (Type 2 DM), otherwise healthy adults with periodontitis, and individuals with no periodontal disease in order to assess whether diabetes alters IL-1beta levels. We also examined relationships between GCF levels and the clinical parameters of pocket depth, plaque index, and bleeding index in each group. Seventeen patients with Type 2 DM, 17 adult periodontitis patients (AP), and 17 healthy controls were selected. The levels of IL-1beta in the GCF were quantified by ELISA. The mean IL-1beta concentrations in the Type 2 DM, AP, and control groups were 200.1 +/- 65.34 pg/microl, 131.35 +/- 67.66 pg/microl, and 80.0 +/- 36.08 pg/microl, respectively. The levels in the diabetic patients were significantly higher than those in the AP and control subjects. There were no significant correlations between IL-1beta level and any of the clinical data parameters for each group. We believe that the macrophages may over produce IL-beta in Type 2 DM and increased IL-1beta levels in diabetic patients could be linked to altered immune function.  相似文献   

18.
目的 分析慢性牙周炎患者血浆和龈沟液中蛋白羰基水平,评价慢性牙周炎引起的氧化应激下蛋白氧化损伤情况.方法 本研究共纳入慢性牙周炎组患者24例和正常对照组牙周健康者22例.对所有对象进行详细的口腔检查,获取外周血和龈沟液样本,检测血浆和龈沟液中蛋白羰基的水平,分析蛋白羰基水平与牙周临床参数的相关性.结果 慢性牙周炎组患者...  相似文献   

19.
Cathepsin-K is a highly expressed cysteine protease, and it plays a key role in bone remodeling and cartilage breakdown in bone. Cathepsin-K is used as a well-known marker of osteoclast activity, because this enzyme is mainly derived from osteoclasts. The receptor activator for NF-kappaB ligand (RANKL) plays an important role in osteoclast formation. Although a recent study suggests the involvement of RANKL in the pathogenesis of periodontal disease, no one has previously examined the level of cathepsin-K in the body fluid of human subjects. If the presence of cathepsin-K, as well as RANKL, can be detected in body fluids, it would be indirect proof of the differentiation and/or activation of osteoclasts in the tissues bathed by these fluids. This communication reports on the in vivo concentrations of cathepsin-K and RANKL in the gingival crevicular fluid (GCF) of normal subjects and those patients with severe, moderate, and mild forms of the disease. Increased concentrations of cathepsin-K and RANKL were detected in the GCF from patients with periodontitis (P<0.005 versus control subjects). Also, there was a positive correlation between cathepsin-K and RANKL levels (r=0.726), suggesting that both of them contribute to osteoclastic bone destruction in periodontal disease.  相似文献   

20.
ObjectiveTo estimate the levels of sCD14 in gingival crevicular fluid and serum under periodontally-healthy and diseased conditions.MethodsThe subjects were divided into three groups of 15, each as follows: healthy, gingivitis, and periodontitis. Periodontal parameters including Probing pocket depth, Clinical attachment level, Bleeding index, and Plaque index. Gingival crevicular fluid and serum samples were collected and analyzed for sCD14 levels using commercially-available ELISA kits.ResultsThe mean concentration of sCD14 in GCF was significantly lower in the gingivitis (134.5 ± 26.85 ng/mL) and periodontitis (103.23 ± 20.36 ng/mL) groups than in the healthy group (172.77 ± 46.33 ng/mL); p < 0.001. The mean serum concentration of sCD14 in the healthy group was 1528.13 ± 387.37 ng/mL, which was significantly less than that of the periodontitis group (2051.50 ± 381.10 ng/mL); p = 0.011.ConclusionsThe serum sCD14 levels in the periodontitis groups were significantly higher than those in the healthy controls. The levels of sCD14 in GCF were significantly lower in the gingivitis and periodontitis groups than in the healthy group.  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