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1.
Bacterial-derived lipopolysaccharides (LPS) can cause defective intestinal barrier function and play an important role in the development of inflammatory bowel disease. In this study, a nanocarrier based on chitosan and fucoidan was developed for oral delivery of berberine (Ber). A sulfonated fucoidan, fucoidan-taurine (FD-Tau) conjugate, was synthesized and characterized by Fourier transform infrared (FTIR) spectroscopy. The FD-Tau conjugate was self-assembled with berberine and chitosan (CS) to form Ber-loaded CS/FD-Tau complex nanoparticles with high drug loading efficiency. Berberine release from the nanoparticles had fast release in simulated intestinal fluid (SIF, pH 7.4), while the release was slow in simulated gastric fluid (SGF, pH 2.0). The effect of the berberine-loaded nanoparticles in protecting intestinal tight-junction barrier function against nitric oxide and inflammatory cytokines released from LPS-stimulated macrophage was evaluated by determining the transepithelial electrical resistance (TEER) and paracellular permeability of a model macromolecule fluorescein isothiocyanate-dextran (FITC-dextran) in a Caco-2 cells/RAW264.7 cells co-culture system. Inhibition of redistribution of tight junction ZO-1 protein by the nanoparticles was visualized using confocal laser scanning microscopy (CLSM). The results suggest that the nanoparticles may be useful for local delivery of berberine to ameliorate LPS-induced intestinal epithelia tight junction disruption, and that the released berberine can restore barrier function in inflammatory and injured intestinal epithelial.  相似文献   

2.
In this paper, the surface of magnetic manganese ferrite nanoparticles (MFN) was modified using cetyl trimethylammonium bromide (CTAB). The modified MFN was studied using Fourier transform infrared spectroscopy (FTIR). The adsorption capacity of surface modified MFN (MFN-CTAB) was investigated for dye removal for single and ternary systems. Three anionic dyes, C.I. Direct Red 80 (DR80), C.I. Direct Red 31 (DR31), and C.I. Acid Blue 92 (AB92), were used as model compounds. The effects of operational parameters on dye removal (i.e. adsorbent dosage, dye concentration and salt) and the kinetic and isotherm of dye adsorption were studied. The adsorption kinetic for the dyes was found to be well described by the pseudo-second order model. The maximum dye adsorption capacity (Q 0) of MFN-CTAB for DR80, DR31 and AB92 was 83 mg/g, 59 mg/g and 70 mg/g, respectively. The adsorption isotherm data were analyzed using the Langmuir, Freundlich, and Temkin equations. The results revealed that the Langmuir model fitted the adsorption data better. The results showed that the MFN-CTAB as a magnetic adsorbent might be a suitable alternative to remove dyes from colored aqueous solutions.  相似文献   

3.
We determined whether nanocarriers can penetrate into plant roots and be transported upward, from the root to stem, as well as studied the effect of the physical state of the lipid matrix of the nanocarriers on their penetration and transportation in plants. Firstly, solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC), and lipid-based nanoemulsions (NE) with similar characteristics (particle size, polydispersity index, and zeta potential) were successfully prepared by the combined method of hot homogenization and sonication, with beeswax as a solid lipid, corn oil as a liquid lipid, and Nile Red as a fluorescent active-ingredient. Penetration of nanocarriers into the roots and their transportation to the stem were visualized using confocal laser scanning microscopy. The images of vertical sections illustrated that NE penetrated into the root and was transported upward at a rate faster than did NLC and SLN, because of its relatively higher flexibility. While it took only 1 day for NE to penetrate into the center of the root and be transported upward to up to 4 cm of the stem, it took 3 and 6 days, respectively, for NLC and SLN to achieve the same. This study provides an important basic background required to generate a new generation of pesticide formulations, where pesticides will be encapsulated in nanocarriers, which in turn will be embedded into a patch that will be stuck on the root or stem. This would minimize pesticide loss, resulting in higher commercial profit and better environmental protection.  相似文献   

4.
In this study, residual shell biomass of Corylus avellana L. was used as potential biosorbent for biosorption of a model industrial hetero-bireactive dye. The biosorbent was characterized by FTIR and SEM. The batch biosorption studies were performed as a function of dye concentration and contact time. The biosorption of dye was found to be very quick. Various kinetic and isotherm models were used to evaluate the obtained experimental data. The biosorption kinetic was best represented by the pseudo-second-order model while the biosorption equilibrium was best described by Langmuir model. The maximum dye biosorption capacity of biosorbent based on Langmuir isotherm was obtained as 74.527 mg g-1. These results showed that the use of such plant waste biomass in biosorption system could be a feasible method for the removal of such recalcitrant dye from industrial effluents to reduce operating costs.  相似文献   

5.
Background: Progress in the field of biology and biochemistry has led to the discovery of numerous bioactive peptides and proteins in the last few decades. Delivery of therapeutic proteins/peptides has received a considerable amount of attention in recent years. Methods: In this study, a two-step desolvation method was used to produce biodegradable hydrophilic gelatin nanoparticles (GNP) as a delivery system of protein model (BSA). The size and shape of the nanoparticles were examined by dynamic light scattering and scanning electron microscopy. Results: Particles with a mean diameter of 200-300 nm were produced and the percentage of entrapment efficiency was found to be 87.4. The optimum amount of theoretical BSA loading was obtained, the release of BSA was monitored in vitro, and the mechanism of release was studied. The BSA release profile showed a biphasic modulation characterized by an initial, relatively rapid release period, followed by a slower release phase. Conclusion: Results show that the two-step desolvation is an appropriate method for preparing GNP as a delivery vehicle for BSA. Key Words: Gelatin, Nanoparticles, Bovine serum albumin  相似文献   

6.
In this study, we developed novel chitosan/fucoidan nanoparticles (CS/F NPs) using a simple polyelectrolyte self-assembly method and evaluated their potential to be antioxidant carriers. As the CS/F weight ratio was 5/1, the CS/F NPs were spherical and exhibited diameters of approximately 230–250 nm, as demonstrated by TEM. These CS/F NPs maintained compactness and stability for 25 day in phosphate-buffered saline (pH 6.0–7.4). The CS/F NPs exhibited highly potent antioxidant effects by scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH), reducing the concentration of intracellular reactive oxygen species (ROS) and superoxide anion (O2) in stimulated macrophages. The DPPH scavenging effect of CS/F NPs primarily derives from fucoidan. Furthermore, these CS/F NPs activated no host immune cells into inflammation-mediated cytotoxic conditions induced by IL-6 production and NO generation. The MTT cell viability assay revealed an absence of toxicity in A549 cells after exposure to the formulations containing 0.375 mg NPs/mL to 3 mg NPs/mL. Gentamicin (GM), an antibiotic, was used as a model drug for an in vitro releasing test. The CS/F NPs controlled the release of GM for up to 72 h, with 99% of release. The antioxidant CS/F NPs prepared in this study could thus be effective in delivering antibiotics to the lungs, particularly for airway inflammatory diseases.  相似文献   

7.
Age-related macular degeneration (AMD) is a progressive eye disease that causes irreversible impairment of central vision, and effective treatment is not yet available. Extracellular accumulation of amyloid-beta (Aβ) in drusen that lie under the retinal pigment epithelium (RPE) has been reported as one of the early signs of AMD and was found in more than 60% of Alzheimer’s disease (AD) patients. Extracellular deposition of Aβ can induce the expression of inflammatory cytokines such as IL-1β, TNF-α, COX-2, and iNOS in RPE cells. Thus, finding a compound that can effectively reduce the inflammatory response may help the treatment of AMD. In this research, we investigated the anti-inflammatory effect of the coral-derived compound 4-(phenylsulfanyl) butan-2-one (4-PSB-2) on Aβ1-42 oligomer (oAβ1-42) added to the human adult retinal pigment epithelial cell line (ARPE-19). Our results demonstrated that 4-PSB-2 can decrease the elevated expressions of TNF-α, COX-2, and iNOS via NF-κB signaling in ARPE-19 cells treated with oAβ1-42 without causing any cytotoxicity or notable side effects. This study suggests that 4-PSB-2 is a promising drug candidate for attenuation of AMD.  相似文献   

8.
In this paper, CuO/CNT nanocomposite was synthesized and its photocatalytic dye degradation ability for colored textile wastewater was studied. The characteristics of the nanocomposite were investigated by XRD, SEM and FTIR. The photodegradation of Direct Red 31 (DR31) and Reactive Red 120 (RR120) by CuO/CNT in presence of H2O2 was investigated. Photocatalytic dye degradation was determined by UV-vis spectrophotometer. Effects of catalyst dosage, initial dye concentration and salt on photodegradation performance were studied. The photocatalytic dye degradation ability of pure CuO and CuO/CNT nanocomposite is 78 % and 89 % for DR31 and 70 % and 87 % for RR120, respectively. The results showed that CNT increased the photocatalytic activity of CuO. The presence of salt decreases dye degradation efficiency. The dye degradation kinetics by nanocomposite followed first-order kinetic model. The reaction rate at 0.005 g catalyst was 0.0137 and 0.0105 min-1 for DR31 and RR120, respectively. It was found that the CuO/CNT nanocomposite as a photocatalyst could be used to degrade dyes from colored wastewater.  相似文献   

9.
There is an increasing body of evidence of the positive impact of several marine lipids on human health. These compounds, which include ω-3 polyunsaturated fatty acids, have been shown to improve blood lipid profiles and exert anti-inflammatory and cardioprotective effects. The high instability of these compounds to oxidative deterioration and their hydrophobicity have a drastic impact in their pharmacokinetics. Thus, the bioavailability of these compounds may be affected, resulting in their inability to reach the target sites at effective concentrations. In this regard; micro/nanoparticles can offer a wide range of solutions that can prevent the degradation of targeted molecules, increase their absorption, uptake and bioavailability. In this work we will present the options currently available concerning micro- and nanodelivery systems for marine lipids; with emphasis on micro/nanoparticles; such as micro/nanocapsules and emulsions. A wide range of bottom-up approaches using casein, chitosan, cyclodextrins, among others; will be discussed.  相似文献   

10.
The aim of this study was to examine the influence of dyeing on antibacterial efficiency of corona activated polyamide and polyester fabrics loaded with colloidal Ag nanoparticles as well as the influence of the presence of Ag nanoparticles on the color change of dyed fabrics. C.I. Acid Green 25 and C.I. Disperse Blue 3 were used for dyeing of polyamide fabrics and C.I. disperse violet 8 for polyester fabrics. The color change of polyamide fabrics depends on the dye type, which was generally lower compared to polyester fabrics. Antibacterial efficiency of Ag loaded fabrics was tested against Gram-positive bacterium Staphylococcus aureus and Gram-negative bacterium Escherichia coli. Corona activated polyester and polyamide fabrics showed excellent antibacterial efficiency independently of order of dyeing and Ag loading. The morphology of fibers loaded with Ag nanoparticles was assessed by SEM and atomic absorption spectroscopy for elemental analysis.  相似文献   

11.
Mucosal delivery of antigens can induce both humoral and cellular immune responses. Particularly, the nasal cavity is a strongly inductive site for mucosal immunity among several administration routes, as it is generally the first point of contact for inhaled antigens. However, the delivery of antigens to the nasal cavity has some disadvantages such as rapid clearance and disposition of inhaled materials. For these reasons, remarkable efforts have been made to develop antigen delivery systems which suit the nasal route. The use of nanoparticles as delivery vehicles enables protection of the antigen from degradation and sustains the release of the loaded antigen, eventually resulting in improved vaccine and/or drug efficacy. Chitosan, which exhibits low toxicity, biodegradability, good cost performance, and strong mucoadhesive properties, is a useful material for nanoparticles. The present review provides an overview of the mucosal immune response induced by nanoparticles, recent advances in the use of nanoparticles, and nasal delivery systems with chitosan nanoparticles.  相似文献   

12.
Background: P2X4 receptor (P2X4R), a purinoceptor expressed in activated spinal microglia, plays a key role in the pathogenesis of neuropathic pain. Spinal nerve injury induces up-regulation of P2X4R on activated microglia in the spinal cord, and blockade of this receptor can reduce neuropathic pain. The present study was undertaken to determine whether paroxetine, an inhibitor of P2X4R, could attenuate allodynia and hyperalgesia in chronic constriction injury (CCI) model of neuropathic pain when used preemptively or after the sciatic nerve injury. Methods: Male Wistar rats (150-200 g, n = 6) were divided into 3 different groups: 1- CCI vehicle-treated group, 2- Sham group, and 3- CCI paroxetine-treated group. Paroxetine (10 mg/kg, i.p.) was administered 1 h before surgery and continued daily until day 14. In other part of the study, paroxetine (10 mg/kg, i.p.) was administered at day 7 post injury and continued daily until day 14. von Frey filaments for mechanical allodynia and analgesia meter for thermal hyperalgesia were used to assay pain behavior. Results: In a preventive paradigm, paroxetine significantly attenuated both mechanical allodynia and thermal hyperalgesia (P<0.001). A significant decrease in pain behavior was seen with paroxetine on existing allodynia (P<0.001) and hyperalgesia (P<0.01) when initiated at day 7 post injury. Conclusion: It seems that paroxetine can attenuate pain behavior when administered before and also after sciatic nerve injury in CCI model of neuropathic pain. Key Words: Paroxetine, P2X4 receptor (P2X4R), Allodynia, Hyperalgesia  相似文献   

13.
The renewable, proteinaceous, marine biopolymer spongin is yet the focus of modern research. The preparation of a magnetic three-dimensional (3D) spongin scaffold with nano-sized Fe3O4 cores is reported here for the first time. The formation of this magnetic spongin–Fe3O4 composite was characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential thermal analysis (DTA) (TGA-DTA), vibrating sample magnetometer (VSM), Fourier-transform infrared spectroscopy (FTIR), and zeta potential analyses. Field emission scanning electron microscopy (FE-SEM) confirmed the formation of well-dispersed spherical nanoparticles tightly bound to the spongin scaffold. The magnetic spongin–Fe3O4 composite showed significant removal efficiency for two cationic dyes (i.e., crystal violet (CV) and methylene blue (MB)). Adsorption experiments revealed that the prepared material is a fast, high-capacity (77 mg/g), yet selective adsorbent for MB. This behavior was attributed to the creation of strong electrostatic interactions between the spongin–Fe3O4 and MB or CV, which was reflected by adsorption mechanism evaluations. The adsorption of MB and CV was found to be a function of pH, with maximum removal performance being observed over a wide pH range (pH = 5.5–11). In this work, we combined Fe3O4 nanoparticles and spongin scaffold properties into one unique composite, named magnetic spongin scaffold, in our attempt to create a sustainable absorbent for organic wastewater treatment. The appropriative mechanism of adsorption of the cationic dyes on a magnetic 3D spongin scaffold is proposed. Removal of organic dyes and other contaminants is essential to ensure healthy water and prevent various diseases. On the other hand, in many cases, dyes are used as models to demonstrate the adsorption properties of nanostructures. Due to the good absorption properties of magnetic spongin, it can be proposed as a green and uncomplicated adsorbent for the removal of different organic contaminants and, furthermore, as a carrier in drug delivery applications.  相似文献   

14.
Marine-derived substances are known for their beneficial influences on aquatic animals’ performances and are recommended to improve intestinal health, immunity, and anti-oxidative status. The present study investigates the role of chitosan nanoparticles on the intestinal histo-morphometrical features in association with the health and immune response of Grey Mullet (Liza ramada). Chitosan nanoparticles are included in the diets at 0, 0.5, 1, and 2 g/kg and introduced to fish in a successive feeding trial for eight weeks. The final body weight (FBW), weight gain (WG), and specific growth rate (SGR) parameters are significantly increased while feed conversion ratio (FCR) decreases by chitosan nanoparticles compared to the control (p < 0.05). The morphometric analysis of the intestines reveals a significant improvement in villus height, villus width, and the number of goblet cells in chitosan-treated groups in a dose-dependent manner. Additionally, there is a positive correlation between the thickness of the enterocyte brush border and the chitosan dose, referring to an increasing absorptive activity. Histologically, the intestinal wall of Grey Mullet consists of four layers; mucosa, sub-mucosa, tunica muscularis (muscular layers), and serosa. The histological examination of the L. ramada intestine shows a normal histo-morphology. The epithelial layer of intestinal mucosa is thrown into elongated finger-like projections, the intestinal villi. The values of hemoglobin, hematocrit, red blood cells (RBCs), total protein (TP), albumin, and globulin are significantly increased in fish fed 1, and 2 g/kg of chitosan nanoparticles compared to fish fed 0 and 0.5 g/kg (p < 0.05). The highest levels of TP and albumin are observed in fish fed 1 g/kg diet (p < 0.05). The lysozyme activity and phagocytic index are significantly enhanced by feeding chitosan nanoparticles at 0.5, 1, and 2 g/kg, whereas the phagocytic activity is improved in fish fed 1 and 2 g/kg (p < 0.05). The highest lysozyme activity and phagocytic index are observed in fish fed 1 g/kg. SOD is significantly activated by feeding chitosan nanoparticles at 1 g/kg. Simultaneously, glutathione peroxidase (GPx) and catalase (CAT) activities also are enhanced by feeding chitosan at 1 and 2 g/kg, compared to fish fed 0 and 0.5 g/kg (p < 0.05). The highest GPx and CAT activities are observed in fish fed 1 g/kg (p < 0.05). Conversely, the malondialdehyde (MDA) levels are decreased by feeding chitosan at 1 and 2 g/kg, with the lowest being in fish fed 1 g/kg (p < 0.05). To summarize, the results elucidate that L. ramada fed dietary chitosan nanoparticles have a marked growth rate, immune response, and anti-oxidative response. These improvements are attributed to the potential role of chitosan nanoparticles in enhancing intestinal histo-morphometry and intestinal health. These results soundly support the possibility of using chitosan nanoparticles at 1–2 g/kg as a feasible functional supplement for aquatic animals.  相似文献   

15.
In this paper, poly(amido primary-secondary amine) (PAPSA) as a high capacity polymeric adsorbent was synthesized. Dye removal ability of PAPSA from single and binary systems was investigated. The functional groups of PAPSA were studied using Fourier transform infrared (FTIR). Acid Blue 92 (AB92), Direct Red 23 (DR23), and Direct Red 81 (DR81) were used as model compounds. The kinetic and isotherm of dye adsorption were studied. The effect of operational parameter such as adsorbent dosage, dye concentration, and pH on dye removal was evaluated. It was found that adsorption of dyes onto PAPSA showed Langmuir isotherm. The maximum dye adsorption capacity (Q 0) of PAPSA was 10000 mg/g, 12500 mg/g, and 10000 mg/g for AB92, DR23, and DR81, respectively. Adsorption kinetic of dyes followed pseudo-second order kinetics. Dye desorption tests showed that the dye release of 85 % for AB92, 91 % for DR23 and 89 % for DR81 were achieved in aqueous solution at pH 12. The results showed that the PAPSA as a polymeric adsorbent with high dye removal ability might be a suitable alternative to remove dyes from colored wastewater.  相似文献   

16.
In this paper, soy meal hull activated carbon (SMHAC) and titania nanoparticle (TiO2) were used as catalysts to degrade dyes. Activated carbon was prepared using soy meal hull. Degradation of dyes using single and binary catalyst systems was studied. Textile dyes were used as model pollutants. Photocatalytic dye degradation and mineralization were studied using UV-Vis spectrophotometer and ion chromatography (IC). The effects of pH, initial dye concentration, and salt on dye degradation were investigated. Dye solutions were decolorized completely (100 %). The presence of salts decreased dye degradation rate. Degradation of dyes followed first order kinetics model. Formate, acetate, and oxalate were detected as dominant aliphatic intermediates during dye degradation process. Nitrate, sulfate, and chloride anions were detected as dye mineralization products.  相似文献   

17.
Inorganic polyphosphate (polyP) is a widely distributed polymer found from bacteria to animals, including marine species. This polymer exhibits morphogenetic as well as antiviral activity and releases metabolic energy after enzymatic hydrolysis also in human cells. In the pathogenesis of the coronavirus disease 2019 (COVID-19), the platelets are at the frontline of this syndrome. Platelets release a set of molecules, among them polyP. In addition, the production of airway mucus, the first line of body defense, is impaired in those patients. Therefore, in this study, amorphous nanoparticles of the magnesium salt of polyP (Mg-polyP-NP), matching the size of the coronavirus SARS-CoV-2, were prepared and loaded with the secondary plant metabolite quercetin or with dexamethasone to study their effects on the respiratory epithelium using human alveolar basal epithelial A549 cells as a model. The results revealed that both compounds embedded into the polyP nanoparticles significantly increased the steady-state-expression of the MUC5AC gene. This mucin species is the major mucus glycoprotein present in the secreted gel-forming mucus. The level of gene expression caused by quercetin or with dexamethasone, if caged into polyP NP, is significantly higher compared to the individual drugs alone. Both quercetin and dexamethasone did not impair the growth-supporting effect of polyP on A549 cells even at concentrations of quercetin which are cytotoxic for the cells. A possible mechanism of the effects of the two drugs together with polyP on mucin expression is proposed based on the scavenging of free oxygen species and the generation of ADP/ATP from the polyP, which is needed for the organization of the protective mucin-based mucus layer.  相似文献   

18.
In this paper, dye removal ability of sodium alginate (SA) as a biopolymer from ternary systems was investigated. Physical characteristics of SA were studied using Fourier transform infra-red (FTIR) and scanning electron microscopy (SEM). Three textile basic dyes were used as model compounds. The adsorption kinetics, isotherms and thermodynamics were studied. The effect of SA dosage, initial dye concentration and pH on dye removal was elucidated. It was found that adsorption kinetics of dyes followed with pseudo-second order kinetics. In addition, dyes followed with Langmuir, and extended Langmuir isotherm in single and ternary systems, respectively. The thermodynamic data showed that the dye adsorption onto SA was a spontaneous, endothermic and physisorption reaction. Based on the data of present investigation, one could conclude that the alginate being a biocompatible, eco-friendly and low-cost adsorbent might be a suitable alternative for elimination of dyes from colored aqueous solutions.  相似文献   

19.
Background: The seladin-1 (selective Alzheimer disease indicator-1), also known as DHCR24, is a gene found to be down-regulated in brain region affected by Alzheimer disease (AD). Whereas, hair follicle stem cells (HFSC), which are affected in with neurogenic potential, it might to hypothesize that this multipotent cell compartment is the predominant source of seladin-1. Our aim was to evaluate seladin-1 gene expression in hair follicle stem cells. Methods: In this study, bulge area of male Wistar rat HFSC were cultured and then characterized with Seladin-1 immunocytochemistry and flow cytometry on days 8 to 14. Next, 9-11-day cells were evaluated for seladin-1 gene expression by real-time PCR. Results: Our results indicated that expression of the seladin-1 gene (DHCR24) on days 9, 10, and 11 may contribute to the development of HFSC. However, the expression of this gene on day 11 was more than day 10 and on 10th day was more than day 9. Also, we assessed HFSC on day 14 and demonstrated these cells were positive for β-ш tubulin, and seladin-1 was not expressed in this day. Conclusion: HFSC express seladin-1 and this result demonstrates that these cells might be used to cell therapy for AD in future. Key Words: Seladin-1 (selective Alzheimer disease indicator-1), Alzheimer disease (AD), Hair follicle stem cells  相似文献   

20.
Iron, as inorganic ion or as oxide, is widely used by biological systems in a myriad of biological functions (e.g., enzymatic, gene activation and/or regulation). In particular, marine organisms containing silica structures—diatoms and sponges—grow preferentially in the presence of iron. Using primary sponge cell culture from S. domuncula–primmorphs—as an in vitro model to study the Demospongiae spiculogenesis, we found the presence of agglomerates 50 nm in diameter exclusively inside sponge specialized cells called sclerocytes. A clear phase/material separation is observed between the agglomerates and the initial stages of intracellular spicule formation. STEM-HRTEM-EDX analysis of the agglomerates (30–100 nm) showed that they are composed of pseudohexagonal nanoparticles between 5 and 15 nm in size, displaying lattice parameters corresponding to hematite (Fe2O3) and mixed iron oxide phases typically attributed to ferritin. Further analysis, using western blotting, inductively coupled plasma mass spectrometry (ICP-MS), sequence alignment analysis, immunostaining and magnetic resonance imaging (MRI), of mature spicule filaments confirm the presence of ferritin within these organic structures. We suggest that S. domuncula can be classified as a dual biomineralizating organism, i.e., within the same cellular structure two distinct biomineralizing processes can occur as a result of the same cellular/metabolic function, spiculogenesis.  相似文献   

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