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1.
Over the last few decades, a number of natural dyes have become non-toxic, eco-friendly and biocompatible substitutes of highly carcinogenic synthetic dyes. Herein, we selected the Acalypha wilkesiana (copper plant) as the source of a natural colorant for auxiliary-free dyeing of cotton, a way forward to eco-friendly dyeing. The bioactive phytochemical constituents of this plant include tannins, flavonoids, phlobatanins, cardiac glycosides, saponins, alkaloids, terpenes and steroids. Both the aqueous and methanol extracts of copper leaf were extracted and applied to unmodified and modified cotton fabrics with the percentage shade depths of 0.5%, 1%, 2%, 4%, 5% and 6% both at pH 4 and 7. The cationized samples rendered substantial improvement in color strength (K/S) values as compared to un-cationized ones. Aqueous and methanolic extracts offered very similar K/S values on cationized samples. Without using any metallic salts as mordants, the color fastness properties like rubbing fastness, washing fastness were also slightly improved due to greater dye fixation on cationized samples compared to uncationized ones. In conclusion, the aqueous extract exhibited dye fixation and color fastness properties comparable to methanolic extract at pH 4 and 7. Thus, it suggested the avoidance of toxic organic solvent for extraction and auxiliary chemicals in subsequent dyeing, a step towards eco-friendly sustainable dyeing.  相似文献   

2.
G. mangostana is available abundantly in Indonesia. Most of the time, the peel of G. mangostana becomes waste. In this study, G. mangostana peel waste was used as a dye for cotton fabrics. The utilization of natural dyes from biomass waste is increasing due to awareness of health and the environment. Extraction was carried out using water (contained 10% citric acid), and ethanol with the ratio of peel waste to solvent was 1:10. In this study, G. mangostana peel dyed-cotton fabrics' antibacterial activity using several kinds of mordant against bacteria Escherichia coli (gram-negative) and Staphylococcus aureus (gram-positive) was studied. Natural mordant from Ixora javanica leaves was also evaluated besides common mordants such as alum (KAl(SO4)2·12H2O), ferrous sulphate (FeSO4·7H2O), and calcium hydroxide (Ca(OH)2). The results showed that G. mangostana peel dyed-cotton fabrics using aqueous extraction with 10% of Ca(OH)2 as a mordant showed the highest antibacterial activity against S. aureus with the zone of inhibition as of 18.14 mm, meanwhile G. mangostana peel dyed-cotton fabrics using ethanol extraction with 10% of ferrous sulphate as mordant showed the highest antibacterial activity against E. coli with the zone of inhibition as of 11.77 mm. Although without mordant, the G. mangostana peel dyed-cotton fabrics, also had antibacterial activity against E. coli and S. aureus as of 10.52 mm and 10.29 mm, respectively. Moreover, G. mangostana peel dyed-cotton fabrics' characterization using SEM, FTIR, and colour chromameter was also conducted. These results indicated G. mangostana peel waste's potential use as an antibacterial agent in fabrics concurrent with natural dyes, which can be very useful in the medical field.  相似文献   

3.
Melia azedarach has a long history of use in furniture production in China. However, its by-product Melia azedarach bark (MAB) and its application as a natural colorant for textiles have not been fully exploited. Increasing awareness of environmental protection and health has led to an increase in the utilization of natural dyes from agricultural and forestry bio-products. This paper focuses on the extraction and application of MAB as a novel natural functional colorant for wool fabrics. Three different solvents (ethanol/water, water with acid or alkali, and ethanol/water with alkali) were used. The chemical composition of the different MAB extracts, the color characteristics, colorfastness, and functional properties of MAB dyed wool fabrics by different dyeing methods were investigated in this work. The extraction solvent of 40% ethanol/water with alkali gave the maximum crude yield of 18.9%. Wool fabrics dyed directly or pre-mordanted with Al3+ and Fe2+ salts showed various hues with acceptable colorfastness to laundering, crocking, and light, as well as functional properties such as UV protection, fluorescence, and anti-moth. MAB extracts proved to be a desirable natural colorant and the dyed wool fabrics proved to be high value-added.  相似文献   

4.
Aqueous reactive dyeing of cotton is considered to be environmentally unfriendly owing to its high consumption of water and salt as well as large discharge of wastewater. However, the industrial applications of current alternative dyeing technologies are difficult to realize due to different problems such as poor dyeing quality, environmental pollution and high cost. Herein, we developed a dyeing approach using hydrophobic deep eutectic solvent (HDES) composed of thymol from thyme leaves and menthol from Mentho haplocalvx Bing (two natural compounds with pharmacological function) to overcome the problems caused by reactive dyeing of cotton. HDES dyeing approach could achieve excellent dyeing properties of cotton by optimizing water content, pick-up and concentration of alkali solution. Dye fixation kinetics of HDES dyeing system was studied based on Lagergren pseudo-first-order and pseudo-second-order dynamics models, compared with aqueous dyeing system. The cotton fabrics dyed in Thy-Men system exhibited excellent levelness, satisfactory colorfastness and color strength without addition of salt. Furthermore, HDES can be reused for 5 cycles of dyeing and the dyed fabrics displayed consistently high color strength values. This dyeing approach provides substantial reduction in wastewater emission and consumption of freshwater and chemicals, which has considerable potential for promoting sustainable development of the textile industry.  相似文献   

5.
This research focuses on flavonoid-based natural dyes for the coloration and antibacterial finishing of wool fabrics. In the present study, we accessed the suitability of biocolorants from Gingko biloba L. waste/fallen leaves extract to develop colored antibacterial wool fabrics to reduce the environmental pollution and dependency of the textile industry on the synthetic antibacterial agents. Specifically, we present a novel method to counteract the growing antibiotic resistance using G. biloba L. leaves extract as a potent antibacterial agent in conjunction with ampicillin. Natural colorants were extracted in 50% aqueous ethanol at 70 °C for 60 min under acid conditions of pH 3. Before dyeing procedures, the extracted dye powder was assessed for thermal stability by TGA analysis. Structural characterization of the extracted dye was done by UV–visible and FT-IR spectral analysis. Optimal dyeing results were achieved at 90 °C for 70 min with a dye concentration of 50% (o.w.f.). Additionally, dye adsorption (Isotherm constants) and dye performances were effectively reported during this study. Pseudo-second order and sips isotherm model provided the best fitting of experimental data with high regression coefficient (R2 = 0.99). Valuated indicators (color strength (K/S), color characteristics, and fastness properties) of dyed wool fabric were effectively reported in response to washing pretreated with different metallic and natural mordants. The antibacterial potential of extracted natural dye was enhanced in combination with ampicillin (synergism) which can be correlated with the significant reduction in the corresponding MIC values. Fe2+ and Sn2+ salts demonstrated negative effects on the antibacterial performance of the dyed wool fabric, whereas most of the biomordants showed enhanced antibacterial performances. The effective use of the extracted yellow dye from G. biloba L. fallen/waste leaves in textile dyeing and finishing will enhance the industrial applications of the green waste over its normal applications.  相似文献   

6.
The present study investigated the antitumor activity of the aqueous-alcoholic extracts from unripe cotton balls ofGossypium indicum. An Exposure of murine B16 melanoma and L1210 lymphoma cells to the extracts resulted in their severe deaths in time- and concentration-dependent manners. Of the extracts, hydrophilic fractions were most efficacious for the antitumor activity and found to contain certain amounts of catechin and its derivatives. The hydrophilic extract fraction C36B2-8 had approximately 10 times more cytotoxic effects on B12 and L1210 cells than on isolated murine thymocytes. High concentrations (>150 μg/ml) of C 36B3-8 mainly induced necrotic cell death. At low concentrations (<100 μg/ml), however, C 36B3-8 induced not only necrosis but also apoptosis of the two tumor cell lines, which was proved by the TUNEL staining and DNA fragmentation techniques. The data indicate that certain ingredients of the cotton ball extract ofG. indicum have an antitumor activity.  相似文献   

7.
Natural dyes owing to their ecofriendly and high biocompatibility make their way for wide spread use in textile industries. However, the process requires lot of dyeing auxiliaries (acid, alkali, metal ions, etc) of which lot of remain unexhausted during dyeing and are discharged as the wastewaters representing a dramatic ecological concern. So, present research work deals with an environmentally benign cleaner production procedure of re-using C. camphora natural dye generated wastewater over and over again for simultaneous coloration and development of UV protective and antioxidant wool fabric. Dyed fabric samples were characterized in terms of CIEL*a*b* and K/S values. Wash fastness characteristics were investigated according to ISO standards. Use of Fe2+ as mordant increases the color characteristics of dyed fabric samples owing to its strong coordinating interactions with dye molecules compared to the other mordants such as Al3+, Sn2+, etc. The use of same dyebath for 5 successive times was done in a systematic way via exhaustion method and the functionalized fabrics were characterized by SEM, FT-IR, and EDX techniques. The pH, conductivity, and COD values were recorded after every cycle. Using same dyebath for 5 times lead to a considerable reduction in COD and conductivity values, hence decreases the effluent level of generated wastewater. In addition, the dyed fabric achieved excellent UV protection and antioxidant properties with good wash fastness characteristics which could be developed to protective clothing in near future.  相似文献   

8.
This work illustrates the potential applications of the raw cotton shell (RCS) and cotton shell biochar (CSB) in the remediation of sulfate contaminants from aqueous solvents. Comprehensively, optimal batch and adsorption kinetics of sulfate by RCS and CSB were intensively analyzed and determined by varying the adsorption parameters. For RCS, the optimal series of parameters were at (pH-7, sulfate conc-150 mgL?1, adsorbent dose- 0.5 g and time-150 min). While for CSB optimum conditions were at (pH-9.8, sulfate conc-100 mgL?1, dosage- 0.1 g and time-90 min). The maximum adsorption efficiency for both RCS and CSB was achieved at 86.47% and 90.77%, respectively. Sulfate adsorption by RCS and CSB was examined by isotherm models and kinetic studies. The data are best suited to the Langmuir isotherm model with the highest RCS and CSB sulfate adsorption capability of 61.35 and 153.85 mg g?1 and followed pseudo-second-order kinetics. Box-Behnken design (BBD) based response surface methodology (RSM) model-based analysis of variance test has demonstrated optimum conditions and sulfate adsorption by both RCS and CSB. The recovery studies on sulfates from marcasite soil were evaluated at different doses of RCS and CSB. This study provides insights into the usage of the developed process towards the circular economy of the sulfates.  相似文献   

9.
The haematological module of the Athlete's Biological Passport (ABP) has significantly impacted the prevalence of blood manipulations in elite sports. However, the ABP relies on a number of concentration‐based markers of erythropoiesis, such as haemoglobin concentration ([Hb]), which are influenced by shifts in plasma volume (PV). Fluctuations in PV contribute to the majority of biological variance associated with volumetric ABP markers. Our laboratory recently identified a panel of common chemistry markers (from a simple blood test) capable of describing ca 67% of PV variance, presenting an applicable method to account for volume shifts within anti‐doping practices. Here, this novel PV marker was included into the ABP adaptive model. Over a six‐month period (one test per month), 33 healthy, active males provided blood samples and performed the CO‐rebreathing method to record PV (control). In the final month participants performed a single maximal exercise effort to promote a PV shift (mean PV decrease ?17%, 95% CI ?9.75 to ?18.13%). Applying the ABP adaptive model, individualized reference limits for [Hb] and the OFF‐score were created, with and without the PV correction. With the PV correction, an average of 66% of [Hb] within‐subject variance is explained, narrowing the predicted reference limits, and reducing the number of atypical ABP findings post‐exercise. Despite an increase in sensitivity there was no observed loss of specificity with the addition of the PV correction. The novel PV marker presented here has the potential to improve the ABP's rate of correct doping detection by removing the confounding effects of PV variance.  相似文献   

10.
In this work we present a green synthetic pathway for the obtaining of bio-surfactants derived from glycerol. By extending a Lewis acid catalyzed reaction between glycidol and primary alcohols we obtained good conversion to the desired monoalkylglycidyl ether (MAGE) for long chain alcohols (n-octanol, n-decanol and n-dodecanol) reaching initial turnover frequency TOF up to 2633 h?1in the case of octanol. The obtained MAGEs were fully characterized and the critical micelle concentration (CMC) was determined for all bio-surfactants using a spectrophotometric approach such as pyrene method with peak difference (P2–P7) linear fitting (octylglyceryl ether: 0.97 ± 0.02 mM; decylglyceryl ether: 0.85 ± 0.03 mM; dodecylglyceryl ether: 0.71 ± 0.04 mM).  相似文献   

11.
Exogenous iron in particulate matter and imbalanced iron homeostasis cause deleterious effects on health. Natural and synthetic iron chelators may be of therapeutic benefit, therefore we evaluated the protective effect of Citrus flavonoids-rich extracts from bergamot and orange juices in iron overloaded human lung epithelial cells.Cytofluorimetric, biochemical and genotoxic analyses were performed in Fe2(SO4)3 exposed A549, pretreated with each extract whose chemical composition was previously detected. Chelating activity was assessed in cells by a calcein ester.Both extracts reduced the generation of reactive oxygen species and membrane lipid peroxidation, improved mitochondrial functionality, and prevented DNA-oxidative damage in iron-exposed cells. Antioxidant effects were attributed to the chelating property, blocking upstream the redox activity of iron. Flavonoid-rich extracts also induced antioxidant catalase.The bergamot and orange juice extracts had a broad-spectrum protective effect. Their use prevents iron oxidative injury and these natural iron chelators could be used as therapeutic agents.  相似文献   

12.
A prospective natural history study was conducted of problem drinkers who were thinking about quitting or reducing their alcohol consumption. Two primary constructs, cognitive appraisals and life events, were measured in a mailed-out baseline survey. A two month follow-up survey identified those who had made reductions in drinking. Regression analyses revealed some support for a cognitive appraisal explanation of change. Respondents who identified more anticipated costs of change were less likely to reduce their drinking. Plans for phase two of this research project - a one year follow-up to identify sustained change attempts - are discussed.  相似文献   

13.
Nigriventrine was isolated from the “armed” spider Phoneutria nigriventer, in which it constitutes about 0.4% of the total venom content. Its structure was determined to be [1,1′-(1-hydroxyhydrazine-1,2-diyl)bis(oxy)bis(4-hydroxy-2,6-dioxopiperidine-4 carboxylic acid)] by NMR, HR-ES/IMS and MS/MS methods. The intracerebroventricular application of nigriventrine in rat brain, followed by the detection of c-Fos protein expression, indicated that the compound was neuroactive in the motor cortex, sensory cortex, piriform cortex, median preoptic nucleus, dorsal endopiriform nucleus, lateral septal nucleus and hippocampus of rat brain. Nigriventrine causes convulsions in rats, even when peripherally applied.  相似文献   

14.
The purpose of these studies was to investigate and compare the composition, stability, antioxidant and anticancer properties and mechanisms of anthocyanin-containing blackberry extracts (ACEs) from selected cultivars and using different extraction methods. ACEs were analyzed for total anthocyanin and phenolics content, polymeric color, and total antioxidant capacity (TAC). The influence of water content in the extraction system was evaluated. A 90-day stability study of the extract and a 48-h stability study of the extract in biologically relevant buffers were completed. The cytotoxic effects of ACEs on HT-29, MCF-7, and HL-60 cells were determined. H2O2 production in culture medium was measured and intracellular ROS levels were quantified. As compared to powder-derived ACEs, puree-derived ACEs contained similar amounts of anthocyanins, but greater levels of phenolics, increased TAC, significantly enhanced production of H2O2, and significantly enhanced cytotoxicity in all cell lines. Catalase could not protect cells from ACE-induced cell death. Cyanidin 3-glucoside exerted anticancer effect by acting synergistically or additively with other active components in the extracts. These data suggest that anthocyanins and non-anthocyanin phenolics in ACEs act synergistically or additively in producing anticancer effects. These studies also provide essential information for the development of fruit-derived ACEs as potential Botanical Drug Products.  相似文献   

15.
Antimicrobial peptides are components of innate immunity that is the first-line defense against invading pathogens for a wide range of organisms. Here, we describe the isolation, biological characterization and amino acid sequencing of a novel neutral Glycine/Leucine-rich antimicrobial peptide from skin secretion of Leptodactylus pentadactylus named leptoglycin. The amino acid sequence of the peptide purified by RP-HPLC (C18 column) was deduced by mass spectrometric de novo sequencing and confirmed by Edman degradation: GLLGGLLGPLLGGGGGGGGGLL. Leptoglycin was able to inhibit the growth of Gram-negative bacteria Pseudomonas aeruginosa, Escherichia coli and Citrobacter freundii with minimal inhibitory concentrations (MICs) of 8 μM, 50 μM, and 75 μM respectively, but it did not show antimicrobial activity against Gram-positive bacteria (Staphylococcus aureus, Micrococcus luteus and Enterococcus faecalis), yeasts (Candida albicans and Candida tropicalis) and dermatophytes fungi (Microsporum canis and Trichophyton rubrum). No hemolytic activity was observed at the 2-200 μM range concentration. The amino acid sequence of leptoglycin with high level of glycine (59.1%) and leucine (36.4%) containing an unusual central proline suggests the existence of a new class of Gly/Leu-rich antimicrobial peptides. Taken together, these results suggest that this natural antimicrobial peptide could be a tool to develop new antibiotics.  相似文献   

16.
李倩  李焱  周铜水 《安徽医药》2017,21(10):1785-1789
目的 分析新鲜丹参根酸水解成分及其抗氧化能力,为丹酚酸类成分在新鲜丹参根中的存在提供可靠依据.方法 采用不同浓度盐酸对新鲜丹参根进行水解处理,通过高效液相色谱法(HPLC)测定提取液中丹酚酸类成分的含量,同时采用紫外分光光度法测定总酚含量及其对DPPH自由基、超氧阴离子自由基的清除率和对脂质过氧化的抑制率.结果 HPLC分析结果表明:新鲜丹参根中除含微量丹酚酸B外,不含其它小分子丹酚酸类成分;经不同浓度盐酸处理后,提取液中丹参素、原儿茶酸、迷迭香酸和总酚含量显著提高;同时对DPPH自由基和超氧阴离子自由基的清除率以及对脂质过氧化的抑制率也显著提高.结论 新鲜丹参根经酸水解后,可以产生小分子丹酚酸类成分,提示这些成分在新鲜丹参根中已存在并可用酸水解出来,说明丹酚酸类成分并不是在采后干燥过程中合成的.  相似文献   

17.
All the currently used type A botulinum neurotoxins for clinical uses are of subtype A1. We compared the efficacy and safety for the first time head-to-head between a novel botulinum toxin A2NTX prepared from subtype A2 and onabotulinumtoxinA (BOTOX) derived from A1 for post-stroke spasticity. We assessed the modified Ashworth scale (MAS) of the ankle joint, the mobility scores of Functional Independence Measure (FIM), and the grip power of the unaffected hand before and after injecting 300 units of BOTOX or A2NTX into calf muscles. The procedure was done in a blinded manner for the patient, the injecting physician, and the examiner. Stroke patients with chronic spastic hemiparesis (15 for A2NTX and 16 for BOTOX) were enrolled, and 11 for A2NTX and 13 for BOTOX (MAS of ankle; > or = 2) were entered for the MAS study. Area-under-curves of changes in MAS (primary outcome) were greater for A2NTX by day 30 (p = 0.044), and were similar by day 60. FIM was significantly improved in the A2NTX group (p = 0.005), but not in the BOTOX group by day 60. The hand grip of the unaffected limb was significantly decreased in the BOTOX-injected group (p = 0.002), but was unaffected in the A2NTX-injected group by day 60, suggesting there was less spread of A2NTX to the upper limb than there was with BOTOX. Being a small-sized pilot investigation with an imbalance in the gender of the subjects, the present study suggested superior efficacy and safety of A2NTX, and warrants a larger scale clinical trial of A2NTX to confirm these preliminary results.  相似文献   

18.
Deltorphin-I, Tyr-d -Ala-Phe-Asp-Val-Val-Gly-NH2 and dermenkephalin, Tyr-d -Met-Phe-His-Leu-Met-Asp-NH2, two highly related opioid peptides from frog skin, display very similar N-termini but strikingly different C-terminal tails. Nevertheless, both peptides are highly potent at, and exquisitely selective for the δ-opioid receptor. To identify common determinants concuring to the remarkably efficient targeting of deltorphin-I and dermenkephalin, combined use of quantitative two-dimensional nuclear magnetic resonance (53 dipolar interactions studied at four temperatures) and energy calculations using simulated annealing generated five groups of deltorphin-I conformers. These groups were pooled into two families whose overall conformation could be described either by a left-handed helix (Family I) or by a big loop (Family II), both stabilized by H-bonds. Proximity of D-Ala2-Phe3-Asp4 and Val5-Val6-Gly7 triads is an obvious structural similarity between almost all groups in both families of structures. Whereas differences between the two families originated mostly from a transition at Ψ Asp4 backbone dihedral angle, the backbone structures at segment 1–4 are similar and spatial arrangements of Tyr1 (t) and Phe3 (g) are identical in one group of each family. Moreover, these two groups have a N-terminal tetrapeptide whose conformation most closely resembles that of a well-defined group of structures for dermenkephalin. Altogether, these results suggest that conformational attributes that are common to dermenkephalin and deltorphin-I, i.e., the backbone conformation of the N-terminal tetrapeptide and preferential orientations in the side-chain of Tyr1 (t) and Phe3 (g) underlie their ability to bind with high selectivity to the δ-opioid receptor.  相似文献   

19.
ABSTRACT

Objective: This study presents a cost-minimisation analysis of moxifloxacin compared to combination treatment with levofloxacin and ceftriaxone in patients hospitalised with community-acquired pneumonia (CAP) in Germany.

Research design and methods: In the MOTIV study, 738 adult patients with CAP requiring hospitalisation and initial parenteral antibiotic therapy were randomised to sequential IV/oral therapy with either moxifloxacin (n?=?368), or levofloxacin and ceftriaxone (n?=?365). The primary effectiveness endpoint was the proportion of patients demonstrating clinical improvement 5–7 days after the completion of study treatment. Subgroup analysis considered patients with severe CAP according to pneumonia severity index (PSI) risk class IV and V, microbiologically proven infection, a history of chronic obstructive pulmonary disease, and a history of cardiovascular disease. The analysis included the cost of study medication, hospital stay, readmission and inpatient procedures and diagnostics. Event frequency in the study was multiplied by German unit costs to estimate per-patient expenditure. The analysis was conducted from a hospital perspective. Sensitivity analysis investigated the effect of costing from an insurer perspective.

Results: No significant difference was found in the percentage of successfully treated patients. Average per patient cost was €2190 for the moxifloxacin group, and €2619 for the levofloxacin + ceftriaxone group (difference –€430, 95% CI: –€138, –€740; p?<?0.05). Variability in total costs was wide, with some patients accruing up to €18?000. Medication cost was significantly lower with moxifloxacin than levofloxacin + ceftriaxone (–€470, 95% CI: –€522, –€421), and accounted for between 15 and 30% of total costs.

Conclusions: In this analysis of patients hospitalised with CAP in Germany, treatment with moxifloxacin was significantly less costly than treatment with levofloxacin and ceftriaxone.  相似文献   

20.
We report the results of a prospective randomised study to evaluate the therapeutic effect of Serenoa repens, Urtica dioica (ProstaMEV®), quercitin and curcumin (FlogMEV®) extracts associated with prulifloxacin in patients affected by chronic bacterial prostatitis (CBP). From a whole population of 284 patients, 143 patients affected by CBP [National Institutes of Health (NIH) class II prostatitis] were enrolled. All patients received prulifloxacin 600 mg daily for 14 days, in accordance with antibiogram results. Patients were split into two groups: Group A received prulifloxacin associated with ProstaMEV® and FlogMEV®; Group B received only antibiotic therapy. Microbiological and clinical efficacies were tested by two follow-up visits at 1 month and 6 months, respectively. Quality of life (QoL) was measured using the NIH Chronic Prostatitis Symptom Index (CPSI) and International Prostatic Symptom Score (IPSS) questionnaires. Group A comprised 106 patients and Group B comprised 37 patients. One month after treatment, 89.6% of patients who had received prulifloxacin associated with ProstaMEV® and FlogMEV® did not report any symptoms related to CBP, whilst only 27% of patients who received antibiotic therapy alone were recurrence-free (P < 0.0001). Significant differences were found between groups in terms of symptoms and QoL (P < 0.0001 for both). Six months after treatment, no patients in Group A had recurrence of disease whilst two patients in Group B did. Questionnaire results demonstrated statistically significant differences between groups (all P < 0.001). The association of S. repens, U. dioica (ProstaMEV®), quercitin and curcumin (FlogMEV®) extracts is able to improve the clinical efficacy of prulifloxacin in patients affected by CBP.  相似文献   

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