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1.
The present study investigated (i) the relationship between standardised morphometric AgNOR parameters (argyrophilic nucleolar organiser region-associated proteins) and MIB1 growth fraction, and (ii) their correlation with immunohistochemical p53, sex steroid receptor status and histopathological differentiation grade in serial paraffin sections from 39 breast carcinomas. Ten sections were double-stained for AgNOR/MIB1. AgNOR parameters correlated significantly with MIB1 growth fraction and p53 protein expression. Significant inverse correlation was found between proliferation markers and oestrogen/progesterone receptor status and histopathological grade. AgNOR expression was significantly higher in cycling (MIB1 positive) tumour cells, than in resting (MIB1 negative) ones, however with exceptions. We conclude, that standardised AgNOR parameters correlate with markers of increased malignant potential in breast carcinomas. However, AgNORs seem to reflect proliferation independent cellular and nucleolar activity of tumour cells, as well. We recommend the use of standardised AgNOR analysis for obtaining sound results in routine paraffin sections.  相似文献   

2.
OBJECTIVE: To evaluate the proliferative activity of different types of nonkeratinizing carcinoma and adjacent normal epithelia in the nasopharynx by the quantitative assessment of argyrophilic nucleolar organizer region (AgNOR) proteins. STUDY DESIGN: Silver staining of nucleolar organizer regions (NORs) was applied to 70 paraffin sections of nonkeratinizing carcinoma in nasopharyngeal biopsies. Fifty-four of the 70 cases had differentiated nonkeratinizing carcinoma (DNC), and the remaining 16 had undifferentiated carcinoma (UC). Nineteen of these 70 samples proved to contain, besides carcinoma, normal epithelia (NE), which was used as a control. The epithelial cells and cancer cells were analyzed for their AgNOR features by image cytometric analysis. RESULTS: As compared with normal epithelia, significant differences were found in mean nuclear area, AgNOR count, mean AgNOR area, AgNOR area ratio and AgNOR area/count ratio between NE and DNC (P < .05) and in mean nuclear area, mean AgNOR area and AgNOR area/count ratio between NE and UC (P < .001). Further, the differences in mean nuclear area, mean AgNOR area and AgNOR area/count ratio were statistically significant between DNC and UC. CONCLUSION: The evaluation of AgNORs is a useful histologic assessment of rapidity of cell proliferation in malignant and benign lesions and demonstrated that UC had more rapidly proliferative activity than DNC in this study.  相似文献   

3.
The count of argyrophilic nucleolar organizer regions (AgNORs) has been proposed as a useful method for evaluating cell replication in human tumours. The current study was undertaken to compare AgNOR values in colorectal cancers with two better established methods for investigating cell proliferation such as bromodeoxyuridine (BrdUrd) and 3[H]-thymidine (3[H]dT) labelling indices (LIs). Because some concern still exists regarding accuracy and reproducibility of AgNOR quantifying methods, we carried out a control study by independently repeating the same measurements (number, area and area per silver-stained NOR particle) in two centres with different operators and computer-assisted image analysers on 40 colorectal carcinomas. AgNOR values recorded in the two centres were strictly correlated (r= 0.75; P < 0.001 for number; r= 0.62, P < 0.01 for area; r= 0.63, P < 0.001 for area per silver-stained NOR particle) and the range of values were almost identical. Then, AgNOR values were compared with BrdUrd and 3[H]dT LIs, respectively obtained by in vivo incorporation and in vitro incubation in the same series of colorectal carcinomas. No correlation was found between AgNOR values and BrdUrd or 3[H]dT LIs. BrdUrd and 3[H]dT LIs were instead reciprocally significantly correlated. No evident correlation was seen between LIs or AgNOR values and clinico-pathological parameters of the tumour. In conclusion, in colorectal neoplasms, AgNOR values did not appear to relate with more direct parameters of cell proliferation. It follows that AgNOR reliability as a biomarker of cell proliferation remains questionable.  相似文献   

4.
We have undertaken an attempt to compare the application efficacy of the proliferative activity markers in differential diagnosis of thyroid Hürthle cell tumors (HCT) using the PCNA and Ki-67 labeling and AgNOR visualisation techniques. The present work is a retrospective analysis of 78 Hürthle cell tumors: 20 Hürthle cell carcinomas (HCC), 32 Hürthle cell adenomas (HCA) and 26 hyperplastic nodules with Hurthle cell metaplasia (HCM). Five microm sections were stained according to AgNOR technique and labeled with antibodies against PCNA and Ki-67. AgNOR dot count in the nucleus and proliferative index (PI - percentage of cells expressing PCNA and Ki-67) in randomly chosen nuclei (100 in case of AgNOR and over 1000 in case of PI) were evaluated in each slide. The mean values of AgNOR dot count, PI-PCNA and PI-Ki-67 in HCC, HCA and HCM were respectively: 5.1, 61.3 and 54.9; 3.4, 42.4 and 38.6 and 2.5, 39.3 and 34.3. Statistically significant difference was found in all the proliferative activity markers between malignant and benign tumors: HCC:HCA (p<0.01) and HCC:HCM (p<0.001). There was no statistically significant difference between HCA and HCM.  相似文献   

5.
DNA ploidy and the proliferative potential in 75 gliomas were investigated using bromodeoxyuridine labelling index (BrdUrd LI), S-phase fraction (SPF) and argyrophilic nucleolar organizer regions (AgNOR) technique. There were 53 highly malignant (AIII-AIV), and 22 low-grade (AI-AII) gliomas. One fragment of the tumour was fixed in Carnoy's solution for AgNOR test, while the other fragments were used for flow cytometric determination of the labelling index, SPF and DNA ploidy. For the BrdUrdLI, tumour samples from each patient were incubated in vitro for one hour at 37 degrees C with BrdUrd using the high pressure oxygen method. The tumours showed variability in the BrdUrdLI values, SPF and AgNOR counts/cell nucleus. The same percentage of DNA aneuploidy (55%) was found in high-grade as well as in low-grade gliomas. Univariate analysis showed that patients with grade I & II gliomas had significantly higher 3-year survival rate (p = 0.0193) than those with grade III and grade IV gliomas. Also patients with lower proliferation rate of tumours (BrdUrdLI < or =2.3% and AgNOR counts < or =2.6%/cell) had higher 3-year survival rate (p<0.03), which can be helpful in prognosis. Tumour ploidy or SPF had no influence on patients' survival (p = 0.7908). Cox multivariate analysis showed that only patients' age > 45 years and high tumour grade (III and IV) were significant unfavourable prognostic factors in terms of patients' survival.  相似文献   

6.
Three different methods for evaluating mitotic activity (mitotic count, mitoses/area, mitotic index) were applied to different types of canine and feline solid tumors to determine the method that is most objective and correlates best with other parameters of cell proliferation. Mitotic activity was evaluated on toluidine blue stained his-tological sections. Slides stained with histochemical (AgNOR proteins) and im-munohistochemical (MEB1, PCNA) markers of cell proliferation were available for each case. Quantitation of mitotic activity and cell proliferation parameters was performed with an image analyzer. Mitotic activity assessment was compared with cell proliferation indices and its ability to discriminate tumors grouped on histologically based criteria including the histological type, malignant or benign characteristics, and grade. A significant correlation by linear regression analysis with other parameters assessing cell proliferation revealed that mitotic index correlated 100% and mitoses/area and mitotic count correlated 40% of the time. In discriminating the proliferative activity of tumors grouped by histological criteria, mitotic index and mitotic count revealed 100% concordance with the other parameters of cell proliferation, while mitoses/areas showed 80% concordance.  相似文献   

7.
 We immunostained mouse lung tumors using a mouse monoclonal antibody against recombinant Ki-67 antigen (clone; MIB 5) to establish an MIB 5 immunostaining method and to determine the extent of MIB 5 labeling to monitor cell proliferation activity in mouse lung tumors. A/J mice, treated with 4-nitroquinoline 1-oxide, were killed after 18 months. One hour before killing, bromodeoxyuridine (BrdU) was injected intraperitoneally. Lung tissues including tumors were fixed with phosphate-buffered 4% paraformaldehyde and embedded in paraffin. For MIB 5 immunostaining, two antigen-retrieval buffers, citrate buffer pH 6 and TRIS-HCl buffer pH 9.5 containing 5% urea, were tested, and constant and reproducible staining was obtained only with the TRIS-HCl buffer. The mean values of the MIB 5-positive cell index (PCI), the BrdU labeling index (LI), and the mitotic cell count for adenocarcinomas were 4.6%, 2.3%, and 7/mm2, and those for adenomas were 1.2%, 0.7%, and 1.3/mm2, respectively. Each of these values was significantly higher for adenocarcinomas than for adenomas. A close correlation was seen between the MIB 5 PCI and the BrdU LI for adenocarcinomas and adenomas and between the MIB 5 PCI and the mitotic cell count in adenocarcinomas. Thus, MIB 5 immunostaining is a useful method for assessing the proliferative activity of mouse tumor tissues. Accepted: 23 June 1998  相似文献   

8.
OBJECTIVE: To evaluate the proliferative activity of cancer cell populations in undifferentiated nasopharyngeal carcinoma (NPC) by quantitative assessment of argyrophilic nucleolar organizer regions (AgNOR) proteins. STUDY DESIGN: Silver-staining of NORs was applied to 18 paraffin sections of undifferentiated NPC containing a vesicular nuclear cancer cell population (VNCC) and spindle-shaped cancer cell population (SSCC). Various features of AgNORs in these two cell populations were analyzed by image cytometry and compared. RESULTS: Mean AgNOR count, mean AgNOR area and AgNOR area-count ratio of VNCC were statistically significantly higher than those of SSCC, while no significant difference was found in AgNOR area/nuclear area ratio between the two cancer cell populations. CONCLUSION: The different cancer cell populations with their distinct morphologic characteristics in undifferentiated NPC have different proliferative activity. The relationship between proliferative heterogeneity of cancer cell populations in undifferentiated NPC and its sensitivity to radiotherapy awaits further study.  相似文献   

9.
Nucleolar organizer region associated proteins (AgNOR proteins) have been identified by means of an argyrophil technique in smears of 60 consecutive fine needle aspirates from lung tumours. AgNOR proteins were visualized as silver-positive granules distributed in loose, intranuclear aggregates. Variations in the number as well as differences in the distribution pattern of AgNOR granules were found among different types of tumours. Except for small cell lung carcinoma, the count of AgNOR granules increased when the differentiation of tumours decreased. In particular well differentiated tumours had relatively few AgNOR granules, distributed in cohesive aggregates. Poorly differentiated tumours had many AgNOR granules organized in loose clusters and small cell lung carcinoma had relatively few granules dispersed throughout the nucleoplasm, showing characteristics unique among all lung neoplasms. The application of the AgNOR technique in cyto-preparations is useful in discriminating between small cell and non-small cell lung carcinomas. Moreover, the pattern of distribution of AgNOR proteins may be of diagnostic value in the assessment of tumours displaying overlap in AgNOR counts.  相似文献   

10.
AIM: The aim of the study was to determine values of a quantitative morphometry analysis of nuclear characteristics and argyrophilic nucleolar organizer regions (AgNORs) in differential cytodiagnosis of benign, atypically proliferating (borderline) and malignant serous ovarian tumours. METHODS: Cytological imprints of benign (n = 20), borderline (n = 19) and malignant (n = 20) ovarian serous tumours were analysed. A computerized, digital analysis was used to determine morphometric nuclear features, the number and characteristics of single AgNORs, cluster AgNORs, total AgNOR and AgNOR area/nucleus (relative area) ratio. According to their size AgNORs were classified in three categories. A one-way variance analysis and post hoc test (Scheffé) were used for statistical analysis. RESULTS: The morphometric nuclear analysis showed that benign, borderline and malignant serous ovarian tumours are statistically different (P < 0.001) according to the area and outline, the values being highest in malignant tumours and lowest in the borderline group. Digital analysis of AgNORs in benign, borderline and malignant groups showed that the total AgNOR number increases with progression of the lesion (meaning tumour malignancy) significantly (P < 0.001) between benign and malignant as well as between borderline and malignant serous ovarian tumours (P < 0.001). The progression of the lesion malignancy was accompanied by a significant (P < 0.001) progressive increase of the total and relative AgNOR area per nucleus. The AgNOR size increases from benign to malignant tumours and a statistically significant difference (P < 0.001) was observed in all three groups regarding small and large AgNORs. CONCLUSION: Combining different markers of morphometric nuclear characteristics and AgNOR values could improve differential cytodiagnosis of benign, borderline and malignant serous ovarian tumours.  相似文献   

11.
鼻咽癌及癌旁上皮细胞的AgNORs定量分析及其生物学意义   总被引:1,自引:0,他引:1  
目的通过鼻咽癌及癌旁上皮的细胞核仁组成区蛋白(NORs)图像定量分析,评价其反映细胞群体增生能力及分化程度等生物学意义。方法对70例鼻咽癌石蜡切片进行银染(AgNORs),应用CAS200图像分析仪分别测定29例癌旁正常腺上皮、19例增生/异型增生柱状上皮、10例增生/异型增生鳞状上皮、54例分化性非角化性癌和16例未分化癌的细胞群体AgNORs参数值并作比较分析;结果每核AgNOR计数、每核AgNOR面积和平均AgNOR面积/粒从正常腺上皮至增生/异型增生柱状上皮至分化性非角化性癌或未分化癌呈现显增加,平均核面积、每核AgNOR面积和平均AgNOR面积/粒从正常腺上皮至增生/异型增生鳞状上皮至未分化癌呈现显增加,差异均有显性,但增生/异型增生鳞状上皮与分化性非角化性癌的AgNOR数值差异没有显差异;与分化性非角化性癌比较,未分化癌的平均核面积、每核AgNOR面积和平均AgNOR面积/粒显增加。结论.AgNORs形态定量分析反映了鼻咽癌及癌旁不同类型鼻咽上皮的细胞增生活性和组织细胞分化程度,但不能反映细胞是否恶性转化;不同组织类型鼻咽癌细胞存在增殖能力的差异,其增生差异程度可能是影响病人对放射线治疗敏感性及其预后的重要因素之一。  相似文献   

12.
DNA ploidy and the proliferative potential in 88 brain tumours were investigated using the bromodeoxyuridine labelling index (BrdUrd LI), S-phase fraction (SPF) and an argyrophilic nucleolar organizer regions (AgNOR) technique. The study included 65 highly malignant (AIII–AIV), and 23 low-grade (AI–AII) gliomas. One fragment of the tumour was fixed in Carnoy's solution for AgNOR test, while the other fragments were used for flow cytometric determination of the labelling index, SPF and DNA ploidy. For the BrdUrdLl, tumour samples from each patient were incubated in vitro for one hour at 37°C with BrdUrd using a high pressure oxygen method. After fixation and staining, the percentages of BrdUrd-labelied cells (BrdUrdLI) and unlabelled S-phase cells (SPF) were evaluated. The tumours showed variability in the BrdUrdLI values, SPF and AgNOR counts/cell nucleus. However, grade dependent differences in the proliferating rate were only found to exist on the basis of BrdUrdLI and AgNOR counts. The same percentage of DNA aneuploidy (56 %) was found in high-grade as well as in low-grade gliomas. A linear – regression analysis showed a significant correlation between the results of three applied methods: BrdUrdLl, SPF and AgNOR counts.  相似文献   

13.
OBJECTIVE: To determine the morphometric characteristics of nuclei and silver-stained nucleolar organizer regions (AgNORs) on cytologic imprints and their value in differential cytodiagnosis of benign, atypical proliferative (borderline) and malignant ovarian mucinous tumors. STUDY DESIGN: Forty-six mucinous ovarian tumor imprints (16 benign, 15 borderline, 15 malignant), were analyzed. Nuclear area, outline, "shape factor" and "form factor" were measured on Papanicolaou-stained smears. AgNOR quantification included 7 variables related to the number and area of single, cluster, total and relative AgNOR content per nucleus and the size distribution of AgNORs. RESULTS: Nuclear area and shape factor allowed distinguishing borderline and malignant tumors. The nuclear area in benign tumors was larger than that in borderline tumors; malignant tumors had the highest values. Single and cluster AgNORs were statistically significantly different in borderline tumors compared with malignant tumors, except for the cluster AgNOR area. The total AgNOR area, number and relative area increased from benign through malignant tumors, with statistically significant differences among all groups. By AgNOR size distribution, small AgNORs discriminate malignant from borderline and benign tumors. CONCLUSION: Combining nuclear morphometry and AgNOR analysis on cytologic imprints could be a diagnostically useful method in the assessment of mucinous ovarian tumors.  相似文献   

14.
A. Kalogeraki, I. Karvela‐Kalogeraki, P. E. Petraki, I. Zois, D. Tamiolakis and E. N. Stathopoulos
Apoptosis and cell proliferation correlated with tumour grade in peritoneal fluids of patients with serous ovarian cancer Objective: Apoptosis and cell proliferation in peritoneal fluids of patients with ovarian serous adenocarcinoma have not been well described in cytology. To investigate the contribution of cell death to the growth of this tumour we analysed both apoptosis and cell proliferation in peritoneal fluids of patients with ovarian serous adenocarcinoma. Methods: We studied 40 tumours from 40 patients with ovarian serous adenocarcinoma. Twelve tumours were high grade, 13 were moderately differentiated and 15 were poorly differentiated. The detection of DNA fragments in situ using the terminal deoxyribonucleotidy transferase (TDT)‐mediated dUTP‐digoxigenin nick‐end labelling (TUNEL) assay was applied to investigate active cell death (apoptosis), and the MIB‐1 antigen was used to investigate cell proliferation. Results: The TUNEL indices were 0.29 ± 0.05, 0.79 ± 0.10 and 2.1 ± 0.90 in Grade I, Grade II and Grade III ovary carcinomas, respectively. The MIB‐1 antigen labelling indices were 6.5 ± 0.09, 12.9 ± 3 and 25.8 ± 6.2, respectively, in the same order of tumour differentiation. The differences in both TUNEL and MIB‐1 labelling indices were statistically significant between Grade I, Grade II and Grade III carcinomas and there was a positive correlation between the two indices (P < 0.001). Conclusions: Apoptosis and cell proliferation increased as the grade of tumour increased in ovarian serous adenocarcinoma, suggesting a rapid turnover of the tumour cells in tumours of higher grade, and may play an important role in the growth and the extension of such cancer cells in the peritoneal cavity.  相似文献   

15.
BACKGROUND: The relationship between the population doubling time and the quantity of silver-stained nucleolar organizer region (AgNOR) interphase proteins was studied in cell culture at three different temperatures used to modulate the cell cycle duration. METHODS: After MIB 1 and AgNOR combined staining, the quantity of AgNOR proteins was measured in cycling cells by image cytometry. RESULTS: Among the several parameters calculated, the AgNOR relative area showed a strong correlation with the changes of the population doubling time induced by different temperatures. CONCLUSIONS: The results support the hypothesis that the cell cycle time and the size of the ribogenesis machinery are coregulated and that measurements of AgNORs can thus be used as a static evaluation of the cell cycle duration in arbitrary units.  相似文献   

16.
BACKGROUND: Cell kinetic data are important indicators of the aggressiveness of tumor and treatment response. The size of a neoplasm depends on the balance between cell proliferation and death. Thus, the analysis of the kinetics of cell proliferation and death may explain differences in the rates of tumour progression. METHODS: We studied apoptosis and proliferative indices in 95 cases of non-small cell lung carcinomas. The analysis was performed on paraffin-embedded tissue, by both MIB-1 immunocytochemical detection to establish the proliferation index and the in-situ end labelling method for the apoptosis index. The two indices were related. RESULTS: Our results showed a high proliferative index and cell loss rate in squamous cell carcinoma, and a low proliferative index and cell loss rate in adenocarcinoma, suggesting two different growth patterns. CONCLUSION: These findings could explain the different biological behaviour and treatment response of the tumours. The tendency of a cancer cell to undergo apoptosis may be especially important for the chemotherapy of malignant tumours with a low growth rate, which are typically resistant to cytostatic agents.  相似文献   

17.
Helicobacter pylori infection has been associated with gastric carcinogenesis. Gastric epithelial cells proliferative rate is accelerated in H. pylori infected adult patients. Our study was performed to evaluate proliferative cell activity in gastric epithelium in the course of H. pylori infection in the early stage of its natural history. Gastric antral biopsy specimens were obtained from thirteen H. pylori positive and seven negative children. To assess replication rates we used nucleolar organiser regions staining with colloidal silver nitrate technique (AgNOR). The number of AgNORs per nucleus, area of single AgNOR, and the quotient of these two parameters (AgNOR content) were analysed. The mean area of AgNOR was lower in H. pylori positive than in negative children. Conversely, both the mean number of AgNOR per nucleus and AgNOR content were higher in infected than non infected subjects. These results show accelerated proliferation of gastric antral epithelial cells in the course of H. pylori infection in children. Such alteration of cell replication occurring in an initial phase of natural history of long lasting infection provides an explanation for the association between acquisition of H. pylori infection in the first years of life and the development of gastric cancer.  相似文献   

18.
AIMS: In breast invasive carcinoma our objectives were I) to compare cellular proliferation determined by MIB1 index with S-phase fraction (SPF) assessed by flow cytometry and with mitotic index, and II) to examine the association of MIB1 index with classical and with new biological prognostic factors [bcl-2, p53, c-erbB-2 and cathepsin D (CD)]. METHODS AND RESULTS: From 102 cases of breast invasive carcinoma, 5-microm thick serial sections were cut from formalin-fixed, paraffin-embedded tissue blocks, and processed for detection of CD, c-erbB-2, p53, bcl-2, Ki-67 antigen MIB-1 and estrogen receptors (ER) and progesterone receptors (PR). SPF was measured by flow cytometry in fresh-frozen tissue samples taken from the carcinoma in each patient. MIB1 index was correlated with SPF (rho=0.45, p<0.0001) and with mitotic index (rho=0.42, p<0.0001). The MIB-1 index was positively associated with the histological grade (p=0.001), tumor size (p=0.04) and the presence of metastases in axillary lymph nodes (p=0.01). MIB1 was associated directly with p53 (p=0.045) and inversely with bcl-2 (p=0.0002). The MIB-1 index was not statistically associated with c-erbB-2. There was a weak association between MIBI index and stromal cell CD. The median MIB1 index was higher in tumors with moderate to strong CD staining of stromal cell, but the difference did not reach statistical significance (p=0.09). CONCLUSIONS: MIB1 index correlates with well established methods for assessing tumor proliferation and with parameters of an aggressive phenotype of tumor. MIB1 index is an effective and readily accessible method for assessing tumor proliferation in breast carcinoma.  相似文献   

19.
OBJECTIVE: To test the significance of various proliferative indices in endometrial carcinoma (EC) since previous investigations failed to yield consistent results that would establish them as factors of clinical importance. STUDY DESIGN: Seventy patients with EC were evaluated for various proliferative indices (mitotic index, Ki-67 index, argyrophilic nucleolar organizer (AgNOR) number and area per nucleus, and p53 protein expression) in relation to image cytometry (nuclear area, diameter and roundness) and standard clinicopathologic features (age, histologic type and grade, and depth of invasion). We also tested the proliferation index (PI), which combines the Ki-67 index and AgNOR area in Ki-67-positive nuclei. Slides from each case were double stained for Ki-67 antigen and AgNOR proteins for this purpose. RESULTS: Mitotic counts were significantly higher in papillary-serous (vs. endometrioid) tumors (P = .0001), high grade (vs. low grade) tumors (P = .0001), deeply invasive (P = .017) and p53-positive tumors (P = .017). AgNOR counts correlated only with age (higher in older women, P = .002), while the PI correlated with mitotic counts (P = 0.28) and marginally with depth of invasion (P = .06). Morphometric variables were associated just with histologic type and grade. p53 Protein was expressed exclusively in invasive tumors and was related strongly to histologic type (P = .0029) and grade (P = .0001). CONCLUSION: Our data reestablish the value of classic histopathologic features (mitotic index, histologic type and grade) as the most important tools for EC evaluation. In addition, we suggest that p53 immunostaining may be used for predicting aggressive behavior in EC.  相似文献   

20.
Studies on the proliferative activity of cells in endometrial hyperplasia and adenocarcinoma were performed using techniques detecting Proliferating Cell Nuclear Antigen (PCNA) and Nucleolar Organizer Regions (NORs). PCNA expression was defined as the percentage of nuclei showing reactivity in 200 cells per sample. The mean AgNOR count per cell was calculated following the analysis of at least 100 nuclei per sample at a magnification of x 400. Student-t test was used for the statistical analysis. The results obtained indicate that the evaluation of cell proliferative activity expressed by AgNOR count and PCNA index can help in the distinction between atypical hyperplasia and well-differentiated adenocarcinoma, and thus can serve as a useful pathological criterion.  相似文献   

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